[Skip to Content]
[Skip to Content Landing]
Table 1.  
Baseline Characteristics of Older Japanese Men and Women
Baseline Characteristics of Older Japanese Men and Women
Table 2.  
Hazard Ratios for Association of Dementia With Adverse Childhood Experiences in Older Japanese Men and Women
Hazard Ratios for Association of Dementia With Adverse Childhood Experiences in Older Japanese Men and Women
Table 3.  
Hazard Ratios for Association of Dementia With Adverse Childhood Experiences in Older Japanese Men and Women
Hazard Ratios for Association of Dementia With Adverse Childhood Experiences in Older Japanese Men and Women
1.
Frankish  H, Horton  R.  Prevention and management of dementia: a priority for public health.  Lancet. 2017;390(10113):2614-2615. doi:10.1016/S0140-6736(17)31756-7PubMedGoogle ScholarCrossref
2.
Livingston  G, Sommerlad  A, Orgeta  V,  et al Dementia prevention, intervention, and care.  Lancet. 2017;390(10113):2673-2734. doi:10.1016/S0140-6736(17)31363-6PubMedGoogle ScholarCrossref
3.
Stern  Y.  Cognitive reserve in ageing and Alzheimer’s disease.  Lancet Neurol. 2012;11(11):1006-1012. doi:10.1016/S1474-4422(12)70191-6PubMedGoogle ScholarCrossref
4.
Kaplan  GA, Turrell  G, Lynch  JW, Everson  SA, Helkala  EL, Salonen  JT.  Childhood socioeconomic position and cognitive function in adulthood.  Int J Epidemiol. 2001;30(2):256-263. doi:10.1093/ije/30.2.256PubMedGoogle ScholarCrossref
5.
Zeki Al Hazzouri  A, Haan  MN, Kalbfleisch  JD, Galea  S, Lisabeth  LD, Aiello  AE.  Life-course socioeconomic position and incidence of dementia and cognitive impairment without dementia in older Mexican Americans: results from the Sacramento area Latino study on aging.  Am J Epidemiol. 2011;173(10):1148-1158. doi:10.1093/aje/kwq483PubMedGoogle ScholarCrossref
6.
Hart  H, Rubia  K.  Neuroimaging of child abuse: a critical review.  Front Hum Neurosci. 2012;6:52. doi:10.3389/fnhum.2012.00052PubMedGoogle ScholarCrossref
7.
Bick  J, Nelson  CA.  Early adverse experiences and the developing brain.  Neuropsychopharmacology. 2016;41(1):177-196. doi:10.1038/npp.2015.252PubMedGoogle ScholarCrossref
8.
Felitti  VJ, Anda  RF, Nordenberg  D,  et al.  Relationship of childhood abuse and household dysfunction to many of the leading causes of death in adults: the Adverse Childhood Experiences (ACE) Study.  Am J Prev Med. 1998;14(4):245-258. doi:10.1016/S0749-3797(98)00017-8PubMedGoogle ScholarCrossref
9.
Danese  A, Moffitt  TE, Harrington  H,  et al.  Adverse childhood experiences and adult risk factors for age-related disease: depression, inflammation, and clustering of metabolic risk markers.  Arch Pediatr Adolesc Med. 2009;163(12):1135-1143. doi:10.1001/archpediatrics.2009.214PubMedGoogle ScholarCrossref
10.
Ritchie  K, Jaussent  I, Stewart  R,  et al.  Adverse childhood environment and late-life cognitive functioning.  Int J Geriatr Psychiatry. 2011;26(5):503-510. doi:10.1002/gps.2553PubMedGoogle ScholarCrossref
11.
Richards  M, Wadsworth  ME.  Long term effects of early adversity on cognitive function.  Arch Dis Child. 2004;89(10):922-927. doi:10.1136/adc.2003.032490PubMedGoogle ScholarCrossref
12.
Whalley  LJ, Staff  RT, Murray  AD, Deary  IJ, Starr  JM.  Genetic and environmental factors in late onset dementia: possible role for early parental death.  Int J Geriatr Psychiatry. 2013;28(1):75-81. doi:10.1002/gps.3792PubMedGoogle ScholarCrossref
13.
Norton  MC, Smith  KR, Ostbye  T,  et al Early parental death and remarriage of widowed parents as risk factors for Alzheimer disease: the Cache County study.  Am J Geriatr Psychiatry. 2011;19(9):814-824. doi:10.1111/j.1532-5415.2010.02806.xPubMedGoogle ScholarCrossref
14.
Persson  G, Skong  I.  A prospective population study of psychosocial risk factors for late onset dementia.  Int J Geriatr Psychiatry. 1996;11:15-22. doi:10.1002/(SICI)1099-1166(199601)11:1<15::AID-GPS262>3.0.CO;2-5Google ScholarCrossref
15.
Radford  K, Delbaere  K, Draper  B,  et al Childhood stress and adversity is associated with late-life dementia in Aboriginal Australians.  Am J Geriatr Psychiatry. 2017;25(10):1097-1106. doi:10.1016/j.jagp.2017.05.008PubMedGoogle ScholarCrossref
16.
Korten  NC, Penninx  BW, Pot  AM, Deeg  DJ, Comijs  HC.  Adverse childhood and recent negative life events: contrasting associations with cognitive decline in older persons.  J Geriatr Psychiatry Neurol. 2014;27(2):128-138. doi:10.1177/0891988714522696PubMedGoogle ScholarCrossref
17.
Rosenman  S, Rodgers  B.  Childhood adversity in an Australian population.  Soc Psychiatry Psychiatr Epidemiol. 2004;39(9):695-702. doi:10.1007/s00127-004-0802-0PubMedGoogle ScholarCrossref
18.
Podcasy  JL, Epperson  CN.  Considering sex and gender in Alzheimer disease and other dementias.  Dialogues Clin Neurosci. 2016;18(4):437-446.PubMedGoogle Scholar
19.
Currie  J, Widom  CS.  Long-term consequences of child abuse and neglect on adult economic well-being.  Child Maltreat. 2010;15(2):111-120. doi:10.1177/1077559509355316PubMedGoogle ScholarCrossref
20.
Haatainen  KM, Tanskanen  A, Kylmä  J,  et al.  Gender differences in the association of adult hopelessness with adverse childhood experiences.  Soc Psychiatry Psychiatr Epidemiol. 2003;38(1):12-17. doi:10.1007/s00127-003-0598-3PubMedGoogle ScholarCrossref
21.
Thompson  MP, Kingree  JB, Desai  S.  Gender differences in long-term health consequences of physical abuse of children: data from a nationally representative survey.  Am J Public Health. 2004;94(4):599-604. doi:10.2105/AJPH.94.4.599PubMedGoogle ScholarCrossref
22.
MacMillan  HL, Fleming  JE, Streiner  DL,  et al.  Childhood abuse and lifetime psychopathology in a community sample.  Am J Psychiatry. 2001;158(11):1878-1883. doi:10.1176/appi.ajp.158.11.1878PubMedGoogle ScholarCrossref
23.
World Health Organization.  World Report on Ageing and Health. Geneva, Switzerland: World Health Organization; 2015.
24.
Amemiya  A, Fujiwara  T, Murayama  H, Tani  Y, Kondo  K.  Adverse childhood experiences and higher-level functional limitations among older Japanese people: results from the JAGES study.  J Gerontol A Biol Sci Med Sci. 2018;73(2):261-266. doi:10.1093/gerona/glx097PubMedGoogle ScholarCrossref
25.
Kondo  K, Rosenberg  M.  Advancing Universal Health Coverage Through Knowledge Translation for Healthy Ageing: Lessons Learnt From the Japan Gerontological Evaluation Study. Geneva, Switzerland: World Health Organization; 2018.
26.
Kondo  K.  Progress in aging epidemiology in Japan: the JAGES Project.  J Epidemiol. 2016;26(7):331-336. doi:10.2188/jea.JE20160093PubMedGoogle ScholarCrossref
27.
Tamiya  N, Noguchi  H, Nishi  A,  et al.  Population ageing and wellbeing: lessons from Japan’s long-term care insurance policy.  Lancet. 2011;378(9797):1183-1192. doi:10.1016/S0140-6736(11)61176-8PubMedGoogle ScholarCrossref
28.
Tani  Y, Suzuki  N, Fujiwara  T, Hanazato  M, Kondo  K.  Neighborhood food environment and dementia incidence: the Japan Gerontological Evaluation Study Cohort Survey.  Am J Prev Med. 2019;56(3):383-392. doi:10.1016/j.amepre.2018.10.028PubMedGoogle ScholarCrossref
29.
Ministry of Health, Labour, and Welfare. Textbook for expert investigators concerning a certification of needed long-term care, revised edition, 2009 [in Japanese]. https://www.mhlw.go.jp/file/06-Seisakujouhou-12300000-Roukenkyoku/0000077237.pdf. Published 2018. Accessed October 23, 2017.
30.
Hikichi  H, Kondo  K, Takeda  T, Kawachi  I.  Social interaction and cognitive decline: results of a 7-year community intervention.  Alzheimers Dement (N Y). 2016;3(1):23-32.PubMedGoogle Scholar
31.
Hikichi  H, Aida  J, Kondo  K,  et al.  Increased risk of dementia in the aftermath of the 2011 Great East Japan earthquake and tsunami.  Proc Natl Acad Sci USA. 2016;113(45):E6911-E6918. doi:10.1073/pnas.1607793113PubMedGoogle ScholarCrossref
32.
Tomata  Y, Sugiyama  K, Kaiho  Y,  et al.  Green tea consumption and the risk of incident dementia in elderly Japanese: the Ohsaki Cohort 2006 Study.  Am J Geriatr Psychiatry. 2016;24(10):881-889. doi:10.1016/j.jagp.2016.07.009PubMedGoogle ScholarCrossref
33.
Hisano  S.  The relationship between Revised Hasegawa Dementia Scale (HDS-R), Mini-Mental State Examination (MMSE), and Bed-Fast Scale, Dementia Scale [in Japanese].  Jpn J Geriatr Psychiatry. 2009;20:883-891.Google Scholar
34.
Saito  T, Murata  C, Saito  M, Takeda  T, Kondo  K.  Influence of social relationship domains and their combinations on incident dementia: a prospective cohort study.  J Epidemiol Community Health. 2018;72(1):7-12. doi:10.1136/jech-2017-209811PubMedGoogle ScholarCrossref
35.
Matsuyama  Y, Fujiwara  T, Aida  J,  et al.  Experience of childhood abuse and later number of remaining teeth in older Japanese: a life-course study from Japan Gerontological Evaluation Study project.  Community Dent Oral Epidemiol. 2016;44(6):531-539. doi:10.1111/cdoe.12246PubMedGoogle ScholarCrossref
36.
Silventoinen  K.  Determinants of variation in adult body height.  J Biosoc Sci. 2003;35(2):263-285. doi:10.1017/S0021932003002633PubMedGoogle ScholarCrossref
37.
Fujiwara  T, Kondo  K, Shirai  K, Suzuki  K, Kawachi  I.  Associations of childhood socioeconomic status and adulthood height with functional limitations among Japanese older people: results from the JAGES 2010 Project.  J Gerontol A Biol Sci Med Sci. 2014;69(7):852-859. doi:10.1093/gerona/glt189PubMedGoogle ScholarCrossref
38.
Tani  Y, Kondo  N, Nagamine  Y,  et al.  Childhood socioeconomic disadvantage is associated with lower mortality in older Japanese men: the JAGES cohort study.  Int J Epidemiol. 2016;45(4):1226-1235. doi:10.1093/ije/dyw146PubMedGoogle Scholar
39.
Wada  T, Ishine  M, Kita  T, Fujisawa  M, Matsubayashi  K.  Depression screening of elderly community-dwelling Japanese.  J Am Geriatr Soc. 2003;51(9):1328-1329. doi:10.1046/j.1532-5415.2003.514207.xPubMedGoogle Scholar
40.
National Institute of Population and Social Security Research. The 15th Japanese National Fertility Survey [in Japanese]. http://www.ipss.go.jp/ps-doukou/j/doukou15/gaiyou15html/NFS15G_html09.html. Published 2017. Accessed November 19, 2019.
41.
Kuh  D, Ben-Shlomo  Y, Lynch  J, Hallqvist  J, Power  C.  Life course epidemiology.  J Epidemiol Community Health. 2003;57(10):778-783. doi:10.1136/jech.57.10.778PubMedGoogle ScholarCrossref
42.
Statistics Bureau, Ministry of Internal Affairs and Communications. Labour force survey FY 1980 [in Japanese]. https://www.e-stat.go.jp/stat-search/files?page=1&layout=datalist&toukei=00200531&tstat=000000110001&cycle=1&year=19800&month=11010303&tclass1=000001062127&tclass2=000001062128&result_back=1. Published 2013. Accessed June 23, 2019.
43.
Minamoto  J.  A study of “dansonjohi”: predominance of men over women in modern Japan [in Japanese].  Bull Inst Hum Rights Stud. 2015;70:1-48.Google Scholar
44.
Tomoda  A, Suzuki  H, Rabi  K, Sheu  YS, Polcari  A, Teicher  MH.  Reduced prefrontal cortical gray matter volume in young adults exposed to harsh corporal punishment.  Neuroimage. 2009;47(2)(suppl):T66-T71. doi:10.1016/j.neuroimage.2009.03.005PubMedGoogle ScholarCrossref
45.
Asada  T. Prevalence of dementia in urban areas and functional disability in dementia for FY2011-2012 [in Japanese]. http://www.tsukuba-psychiatry.com/wp-content/uploads/2013/06/H24Report_Part1.pdf. Published 2013. Accessed December 17, 2019.
46.
Baldwin  JR, Reuben  A, Newbury  JB, Danese  A.  Agreement between prospective and retrospective measures of childhood maltreatment: a systematic review and meta-analysis.  JAMA Psychiatry. 2019;76(6):584-593. doi:10.1001/jamapsychiatry.2019.0097PubMedGoogle ScholarCrossref
47.
Reuben  A, Moffitt  TE, Caspi  A,  et al.  Lest we forget: comparing retrospective and prospective assessments of adverse childhood experiences in the prediction of adult health.  J Child Psychol Psychiatry. 2016;57(10):1103-1112. doi:10.1111/jcpp.12621PubMedGoogle ScholarCrossref
48.
Hardt  J, Rutter  M.  Validity of adult retrospective reports of adverse childhood experiences: review of the evidence.  J Child Psychol Psychiatry. 2004;45(2):260-273. doi:10.1111/j.1469-7610.2004.00218.xPubMedGoogle ScholarCrossref
49.
Tomata  Y, Sugiyama  K, Kaiho  Y, Sugawara  Y, Hozawa  A, Tsuji  I.  Predictive ability of a simple subjective memory complaints scale for incident dementia: evaluation of Japan’s national checklist, the “Kihon Checklist”.  Geriatr Gerontol Int. 2017;17(9):1300-1305. doi:10.1111/ggi.12864PubMedGoogle ScholarCrossref
Limit 200 characters
Limit 25 characters
Conflicts of Interest Disclosure

Identify all potential conflicts of interest that might be relevant to your comment.

Conflicts of interest comprise financial interests, activities, and relationships within the past 3 years including but not limited to employment, affiliation, grants or funding, consultancies, honoraria or payment, speaker's bureaus, stock ownership or options, expert testimony, royalties, donation of medical equipment, or patents planned, pending, or issued.

Err on the side of full disclosure.

If you have no conflicts of interest, check "No potential conflicts of interest" in the box below. The information will be posted with your response.

Not all submitted comments are published. Please see our commenting policy for details.

Limit 140 characters
Limit 3600 characters or approximately 600 words
    1 Comment for this article
    ACES in Japan
    Richard Krugman, MD |
    This is an interesting study. Japan has been slower to recognize the existence of child abuse and neglect than many other countries in the developed world. One of the limitations of this study from my reading is that the authors did not use the Felitti/Anda list of 10 ACES but created their own adaptation. The original ACES list includes five types of child abuse and neglect. In this paper, the authors used only three -- and completely avoided sexual abuse. I suspect that history of sexual abuse in childhood is an important thing to know.
    CONFLICT OF INTEREST: None Reported
    Original Investigation
    Geriatrics
    February 7, 2020

    Association Between Adverse Childhood Experiences and Dementia in Older Japanese Adults

    Author Affiliations
    • 1Department of Global Health Promotion, Tokyo Medical and Dental University, Tokyo, Japan
    • 2Department of Social Preventive Medical Sciences, Center for Preventive Medical Sciences, Chiba University, Chiba, Japan
    • 3Department of Gerontological Evaluation, Center for Gerontology and Social Science, National Center for Geriatrics and Gerontology, Aichi, Japan
    JAMA Netw Open. 2020;3(2):e1920740. doi:10.1001/jamanetworkopen.2019.20740
    Key Points español 中文 (chinese)

    Question  Are adverse childhood experiences associated with the onset of dementia later in life?

    Findings  In a large-scale cohort study of 17 412 older Japanese adults, the cumulative number of adverse childhood experiences was associated with an increased risk of developing dementia.

    Meaning  Having 3 or more adverse childhood experiences was associated with increased dementia risk among older Japanese adults.

    Abstract

    Importance  The prevalence of dementia in Japan has been increasing. Childhood poverty has been associated with increased risk of cognitive impairment, possibly mediated by individuals’ educational paths. However, the associations between dementia and adverse childhood experiences other than poverty and education have not been well documented.

    Objective  To examine the association between adverse childhood experiences and dementia onset among Japanese individuals born before 1948 who grew up during and after World War II.

    Design, Setting, and Participants  A 3-year (2013-2016) follow-up was performed of 17 412 participants in the Japan Gerontological Evaluation Study, a population-based cohort study of adults aged 65 years or older. Data were analyzed in December 2019.

    Main Outcomes and Measures  Dementia onset was assessed through the public long-term care insurance system. Adverse childhood experiences before the age of 18 years were assessed by survey at baseline. Seven adverse childhood experiences were assessed: parental death, parental divorce, parental mental illness, family violence, physical abuse, psychological neglect, and psychological abuse. Participants were classified according to whether they had 0, 1, 2, or 3 or more adverse childhood experiences. Cox regression models were used to estimate hazard ratios for the risk of dementia.

    Results  Among 17 412 participants (9281 women [53.3%]; mean [SD] age, 73.5 [6.0] years), dementia occurred in 703 participants (312 men and 391 women) during a mean follow-up of 3.2 years (range, 2.4-3.3 years). Among all participants, 6804 (39.1%) were older than 75 years; 10 968 (63.0%) reported 0 adverse childhood experiences, 5129 (29.5%) reported 1 adverse childhood experience, 964 (5.5%) reported 2 adverse childhood experiences, and 351 (2.0%) reported 3 or more adverse childhood experiences. Participants who experienced 3 or more adverse childhood experiences had a greater risk of developing dementia compared with those who grew up without adverse childhood experiences, after adjustment for age, sex, childhood economic hardship, nutritional environment, and education (hazard ratio, 2.18; 95% CI, 1.42-3.35). After successive adjustment for adult sociodemographic characteristics, social relationships, health behavior, and health status, this hazard ratio was attenuated but remained statistically significant (1.78; 95% CI, 1.15-2.75; P = .009).

    Conclusions and Relevance  This study found that having 3 or more adverse childhood experiences was associated with increased dementia risk among older Japanese adults.

    Introduction

    With population aging, dementia is a major public health concern globally.1,2 Approximately 47 million people had dementia in 2015 worldwide, and this number is expected to triple by 2050.2 To address the dementia epidemic, an appropriate evidence-based prevention strategy is needed. A recent review2 examined the life-course model of the contributions of modifiable risk factors associated with dementia, including education, hearing loss, hypertension, obesity, smoking, depression, physical inactivity, social isolation, and diabetes. In that model, education showed the second highest percentage in terms of the contribution to the onset of dementia,2 suggesting that childhood environment is crucial to developing enough cognitive reserve to prevent dementia.3 Previous studies4,5 reported that childhood poverty is associated with cognitive impairment, perhaps mediated by individual’s educational path. However, the associations between dementia and adverse childhood experiences other than education and poverty are not well documented.

    Early life exposure to adverse childhood experiences, including parental loss, family psychopathology, and child maltreatment, may be associated with dementia. Direct associations of adverse childhood experiences with dementia can be explained by studying the brain. For example, individuals who experienced adverse childhood experiences show deficits in brain structure and function.6,7 An indirect outcome of adverse childhood experiences on dementia is also possible—that is, adverse childhood experiences are associated with smoking, obesity, and depression, which are well known to be associated with dementia.8,9 Several epidemiological studies10-16 have demonstrated an association between the components of adverse childhood experiences, such as parental death, and cognitive function or dementia in later life. However, comprehensive assessments of the associations of adverse childhood experiences with dementia are scarce, despite multiple types of adverse childhood experiences often co-occurring.8,17 Most of the studies investigating the association between each component of adverse childhood experiences and dementia have small sample sizes of fewer than 500 people and are cross-sectional studies. Moreover, to our knowledge, no study of whether sex differences exist has ever been performed. Dementia prevalence and risk factors vary by sex, possibly because of sex differences in brain development and biological responses to environmental factors, such as adversities, and sex disparities in the level of risk factors of dementia, such as educational attainment.18 Sex differences have been identified for adverse childhood experiences and other subsequent adulthood outcomes, such as physical health problems and well-being.19-22 Therefore, the association between adverse childhood experiences and dementia incidence may also differ between men and women.

    Japan is in a unique case for the investigation of the association between adverse childhood experiences and dementia for 2 reasons. First, Japanese people have the greatest longevity; thus, we can include a large number of older-old (ie, ≥75 years old) individuals in this investigation.23 Second, older Japanese people experienced World War II (1937-1945), which might be associated with adverse childhood experiences. More than one-fifth of Japanese older adults (born before 1948) experienced parental death before the age of 18 years, and the cumulative number of adverse childhood experiences has been associated with a higher level of functional limitations in later life.24 Therefore, older Japanese adults who experienced harmful events resulting from the war might have an increased risk of onset of dementia later in life.

    The Japan Gerontological Evaluation Study is a large-scale cohort study of community-dwelling older Japanese people. Baseline surveys were administered in 2013 to individuals aged 65 years and older who were physically and cognitively independent and then were linked to data on the incidence of dementia until 2016. The participants were born during the period from 1915 to 1948 and grew up during and after World War II. Using these data, we examined the association between adverse childhood experiences and the subsequent emergence of dementia among older adults separately in men and women.

    Methods
    Study Design and Participants

    The Japan Gerontological Evaluation Study was established to evaluate the social determinants of healthy aging in Japan.25,26 The baseline survey was conducted between October and December 2013 for older people living in 24 municipalities throughout Japan. Self-reported questionnaires were distributed by mail to 151 324 people aged 65 years or older without functional disabilities, which was defined as not being certified as eligible for benefits from the long-term care insurance system.27 Participants were informed that participation in the study was voluntary and that completing and returning the questionnaire via mail indicated their consent to participate in the study. The protocol of this study was approved by the Ethics Committees on Research on Human Subjects at Nihon Fukushi University. This study follows the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) reporting guideline.

    A simple random sample was obtained in large municipalities, as well as a complete census of older residents in smaller municipalities. A total of 107 183 participants returned the questionnaire (response rate, 71%), and data for 98 803 of them (92%) were linked to information on dementia onset during the 3-year follow-up period. One-fifth of the sample (19 842 participants) was randomly selected to receive the survey module inquiring about adverse childhood experiences. The following participants were excluded: 100 participants receiving treatment for dementia at baseline survey, 2286 participants missing responses to the questions regarding adverse childhood experiences, and 44 participants who reported that they received care and assistance during walking, bathing, and toileting in their daily lives.

    Dementia Outcome

    Dementia incidence was ascertained during the follow-up period, from 2013 to 2016 (mean [range], 3.2 [2.4-3.3] years), by linking the cohort participants to the standardized in-home assessment and medical examination conducted under Japan’s public long-term care insurance registry.27 The details of the assessment of dementia have been reported elsewhere.28 In brief, trained investigators determined the eligibility for benefits (eg, a home helper or day care) for the applicants by evaluating the following statuses: physical function, activities of daily living, cognitive function, mental and behavioral disorders, adaptation to social life, and past medical treatment.29,30 Investigators classified the applicants on a dementia scale according to the severity of their cognitive impairment.28,31,32 A validation study showed a high correlation with the Mini-Mental State Examination (Spearman rank correlation ρ = −0.74).33 In this study, dementia was defined as level II or higher on the dementia scale—that is, a condition with manifesting at least some symptoms, behaviors, or communication difficulties that hinder daily activities (level II corresponds to a 16-point rating on the Mini-Mental State Examination),33 as described elsewhere.28,32,34

    Adverse Childhood Experiences

    Adverse childhood experiences were assessed using a self-reported questionnaire at baseline. We developed the adverse childhood experience questionnaire for older Japanese people24,35 on the basis of the Adverse Childhood Experiences Study.8 The adverse childhood experience questionnaire consists of 7 questions, querying whether participants had the following experiences before the age of 18 years: interpersonal loss (parental loss or parental divorce), family psychopathology (parental mental illness or family violence), and abuse and neglect (physical abuse, psychological neglect, or psychological abuse). Participants were classified according to whether they had experienced 0, 1, 2, or 3 or more total adverse childhood experiences. Participants who experienced 4 or more adverse childhood experiences accounted for only 0.65% of the sample; therefore, we combined the participants who had 3 or more experiences into 1 category.

    Covariates

    Covariates were assessed by a self-administered questionnaire. Age at baseline was categorized into 4 groups (65-69, 70-74, 75-79, and ≥80 years; corresponding birth years are 1944-1948, 1939-1943, 1934-1938, and 1933 and before, respectively). We included childhood economic hardship and height as other childhood environmental factors. Childhood economic hardship was assessed by a question about whether the family’s financial condition was difficult during childhood (yes or no response).24 Height was used as a proxy for childhood nutritional environment36 and was categorized into 5 groups at 5-cm intervals for each sex (for men, <155, 155-159.9, 160-164.9, 165-169.9, and ≥170 cm; for women, <145, 145-149.9, 150-154.9, 155-159.9, and ≥160 cm).37,38 We included education as an environmental factor from childhood to adolescence and categorized it into 3 groups by years of schooling (≤9, 10-12, or ≥13 years).38 We included adult sociodemographic characteristics (current annual household income and longest held occupation), current social relationships (marital status, frequency of meeting friends, social participation, and employment status), health behavior (smoking), and health status (body mass index [calculated as the weight in kilograms divided by height in meters squared], depressive symptoms, hypertension, diabetes, and hearing loss) as potential mediators. The longest held occupation was categorized as nonmanual (professional, technical, or managerial), manual (clerical, sales or service, skilled labor, agricultural, forestry, fishery, or other), and no occupation.38 The assessment of current social relationships included frequency of meeting friends and acquaintances and social participation in a variety of groups or activities, including volunteer groups, sports groups, leisure activity groups, senior citizens’ clubs, and neighborhood or residents’ associations.38 Depressive symptoms were assessed by the 15-item short form of the Geriatric Depression Scale (Japanese version).39 For hypertension, diabetes, stroke, heart disease, and hearing loss, participants were asked whether they were currently being treated or had sequelae. Covariates with missing data were categorized as missing, and participants with missing data on the covariates were included in the analysis.

    Statistical Analysis

    Cox proportional hazards models were estimated, yielding hazard ratios (HRs) and 95% CIs for dementia incidence during the 3-year follow-up period. Model 1 was adjusted for age, sex, other childhood environmental factors (economic hardship and height), and education. Model 2 was also adjusted for adult health status associated with cardiovascular risk (hypertension, diabetes, stroke, and heart disease). Model 3 was further adjusted for adult sociodemographic characteristics (annual income and longest occupation), social relationships (marital status, frequency of meeting friends, social participation, and employment status), and health behavior (smoking). Model 4 was further adjusted for health status (body mass index, depressive symptoms, and hearing loss). Subsequently, data were analyzed separately for men and women because the interaction term between sex and adverse childhood experiences showed marginal interaction effect (P = .17), and sex differences were reported in studies that examined adverse childhood experiences and subsequent health outcomes.19-22 We applied the multiple imputation methods for adequately addressing missing data on covariates. We generated 50 imputed data sets using the multiple imputation by chained equations with the mi impute chained command in Stata. We performed a mediation analysis to evaluate the mediation effects of adult sociodemographic characteristics, social relationships, health behavior, and health status using the binary mediation command in Stata. All analyses were conducted using Stata statistical software version 14 (StataCorp). Two-sided P < .05 (Pearson χ2 test) was considered statistically significant. Data were analyzed in December 2019.

    Results

    The analytic sample for the present study included 17 412 participants (8131 men [46.7%] and 9281 women [53.3%]; mean [SD] age, 73.5 [6.0] years). Table 1 shows the characteristics of participants. Among all participants, 6804 (39.1%) were older than 75 years, 12 653 (72.7%) were married, 4106 (23.6%) were working, 12 677 (72.8%) were nonsmokers, 7526 (43.2%) were receiving treatment for hypertension, and 2286 (13.1%) were receiving treatment for diabetes. Approximately 1% of participants had 3 cognitive complaints at baseline. Overall, 10 968 (63.0%) reported 0 adverse childhood experiences, 5129 (29.5%) reported 1 adverse childhood experience, 964 (5.5%) reported 2 adverse childhood experiences, and 351 (2.0%) reported 3 or more adverse childhood experiences (Table 1). The prevalence of each adverse childhood experience was similar for men and women. The adverse childhood experience with the highest prevalence was parental death (1881 men [23.1%] vs 2048 women [22.1%]), and that with the second highest prevalence was psychological neglect (1182 men [14.5%] vs 939 women [10.1%]). Only 326 participants overall (1.9%) experienced parental divorce (185 men [2.3%] vs 141 women [1.5%]), and 121 participants overall (0.7%) experienced parental mental illness (74 men [0.9%] vs 47 women [0.5%]). Approximately one-half of participants (7762 [44.6%]) reported that they had economic hardship during childhood, and 39.8% of the participants (6926 participants) had been in school for less than 9 years.

    The percentages of missing values were higher among women than men possibly because of older age—that is, older women may have been reluctant to complete the questionnaire. In particular, for current household income, longest occupation, and employment status, in a national survey conducted in the 1980s,40 40% of working women retired after marriage and 60% of the remaining women retired after the birth of their first child. Thus, women may tend to fail to report their income and occupation. For annual income, data were missing for 1938 women (19.8%) vs 837 men (10.3%); for longest occupation, data were missing for 1133 women (12.2%) vs 459 men (5.6%); and for employment status, data were missing for 816 women (8.8%) vs 193 men (2.4%). The missing responses to the adverse childhood experience questionnaires were similar between men and women (1016 men vs 1260 women; 2276 participants total) (eTable 1 in the Supplement).

    eTable 2 in the Supplement shows the probability that participants who experienced 1 adverse childhood experience would have also experienced other adverse childhood experiences. Among those who experienced only 1 adverse childhood experience, 61% experienced parental death. Approximately one-half of the participants who experienced physical abuse also experienced family violence, psychological neglect, and psychological abuse among both men and women. Similarly, approximately 40% of those who experienced psychological abuse also experienced psychological neglect. Participants who experienced interpersonal loss (parental death or divorce) were more likely to experience psychological neglect compared with other components of adverse childhood experiences. For those with 3 or more adverse childhood experiences, 52% of men and 59% of women (55% overall) had experienced parental death, 84% of men and 88% of women had experienced psychological neglect, 45% of men and 31% of women had experienced physical abuse, and 69% of men and 88% of women had experienced psychological abuse. The proportion of physical abuse was less than 8% for men with fewer than 2 adverse childhood experiences, but 45% for men with 3 or more adverse childhood experiences (eTable 2 in the Supplement). We found that participants who experienced adverse childhood experiences had a lower education level, were more likely to be unmarried, had less social participation, were more likely to have a history of smoking, and were more likely to have depression (all P < .001) (eTable 3 in the Supplement).

    During the 3-year follow-up period, dementia was present in 703 participants (312 men and 391 women) among the analytical sample (cumulative dementia rate: 4.0% in all participants, 3.8% in men, and 4.2% in women). The incidence rate of dementia was 3.4 cases per 100 000 person-years (95% CI, 3.1-3.7 cases per 100 000 person-years) for those who grew up without adverse childhood experiences and 6.0 cases per 100 000 person-years (95% CI, 4.0-9.1 cases per 100 000 person-years) for those who experienced 3 or more adverse childhood experiences (Table 2).

    Table 2 shows the association between the total number of adverse childhood experiences and dementia incidence. The proportional hazards assumption for model was checked by examining log minus log-transformed Kaplan-Meier estimates of the survival plots, and we confirmed no serious violation of the proportional hazards assumption. Participants who experienced 3 or more adverse childhood experiences had a greater risk of developing dementia compared with those who grew up without adverse childhood experiences after adjustment for age, sex, other childhood environmental factors (economic hardship and height), and education (model 1) (HR, 2.18; 95% CI, 1.42-3.35). After successive adjustment for adult sociodemographic characteristics, social relationships, health behavior, and health status (model 4), this HR was attenuated but remained statistically significant (HR, 1.78; 95% CI, 1.15-2.75; P = .009). When we performed a mediation analysis, adult sociodemographic characteristics, social relationships, health behavior, and health status mediated 67% of the association between the adverse childhood experiences and dementia. When stratified by sex, there were associations with dementia for 3 or more adverse childhood experiences for men (HR, 2.20; 95% CI, 1.24-3.90), for 2 adverse childhood experiences for women (HR, 1.66; 95% CI, 1.12-2.48), and for 3 or more adverse childhood experiences for women (HR, 2.17; 95% CI, 1.13-4.15).

    Table 3 shows the association between individual adverse childhood experiences and dementia incidence. Physical abuse (HR, 2.61; 95% CI, 1.65-4.14), psychological neglect (HR, 1.26; 95% CI, 1.02-1.55), and psychological abuse (HR, 1.65; 95% CI, 1.23-2.20) were associated with dementia incidence (model 1). The associations between physical abuse (HR, 2.42; 95% CI, 1.52-3.86) and psychological abuse (HR, 1.35; 95% CI, 1.01-1.81) and dementia remained after adjustment for potential mediators (model 4). When stratified by sex, physical abuse was associated with dementia in men, whereas psychological neglect and abuse were associated with dementia in women. Men who experienced physical abuse had a greater risk of developing dementia after adjustment for age, other childhood environmental factors (economic hardship and height), and education (model 1) (HR, 2.82; 95% CI, 1.64-4.85). This association remained in the final model (HR, 2.70; 95% CI, 1.56-4.70). Women who experienced psychological neglect had a greater risk of developing dementia (HR, 1.51; 95% CI, 1.14-2.00), and those who experienced psychological abuse had a greater risk of developing dementia in model 1 (HR, 1.97; 95% CI, 1.35-2.88). The association between psychological abuse and dementia remained in the final model (HR, 1.66; 95% CI, 1.12-2.44).

    Discussion

    To our knowledge, this is the first study to examine the association between adverse childhood experiences and dementia incidence using a large-scale cohort study of older Japanese people. The cumulative number of adverse childhood experiences was associated with increased risk of developing dementia.

    The current findings are consistent with those of previous studies12-14 that examined the association between childhood parental death and dementia. In the present study, among older people who experienced 3 or more adverse childhood experiences, 55% of them experienced parental death, which was associated with a higher risk of developing dementia. However, having only 1 adverse childhood experience (61% of which were parental deaths) was not associated with dementia incidence, suggesting that the cumulative theory on the association between adverse childhood experience and adult disease41 may support the current findings. A prospective study in Sweden14 showed a dose-response association between dementia and psychosocial risk factors, such as parental death and arduous manual work, during the life course. In the present study, most participants with 3 or more adverse childhood experiences had experienced parental death, psychological neglect, and abuse (eTable 2 in the Supplement). Although it is unclear which adverse childhood experience happened first, parental death alone was not associated with the risk of dementia in old age, but it was associated with increased risk if psychological neglect and abuse were added.

    The association between adverse childhood experiences and dementia incidence decreased after adjusting for social relationships, health behavior, and health status, suggesting that these factors may mediate the association between adverse childhood experiences and dementia. When we performed a mediation analysis, adult sociodemographic characteristics, social relationships, health behavior, and health status mediated 67% of the association between the adverse childhood experiences and dementia. Adverse childhood experiences can hinder opportunities in terms of receiving education, building social relationships, and developing healthy behaviors, thus increasing the risk of diseases associated with the onset of dementia. We found that participants who experienced adverse childhood experiences had a lower education level, were more likely to be unmarried, had less social participation, were more likely to have a history of smoking, and were more likely to have depression (all P < .001) (eTable 3 in the Supplement). Adjusting for cardiovascular risk factors (hypertension, diabetes, stroke, and heart disease) reduced the association between adverse childhood experiences and dementia incidence. This may be partially explained by genetic factors—that is, it is possible that a certain portion of parental death may be attributed to fatal cardiovascular conditions, which are partly inheritable. In this case, cardiovascular diseases can be potential confounders. However, even after adjusting for cardiovascular risk factors, an association between adverse childhood experiences and dementia incidence remained.

    A dose-response association between adverse childhood experiences and dementia incidence was found for women but not for men. Sex differences have also been identified for adverse childhood experiences and other subsequent adulthood outcomes, such as physical health problems and well-being,19-22 possibly because the sensitivity to adverse childhood experiences may differ between men and women. A previous study10 investigating the association between adverse childhood experiences and cognitive function reported that parental death during childhood was associated with poor verbal retrieval only among women but not men. In the current study, more than 60% of women were housewives before 1980, and women were mainly in charge of childcare.42 Thus, it is also possible that performing childcare may remind women of being abused or neglected more often than men. This may be supported by the fact that psychological neglect and abuse were associated with dementia only in women. Duration, starting age, and types of adverse childhood experiences may differ between men and women. The belief that men are superior to women still exists in Japanese culture.43 Therefore, women may have experienced more-severe adverse childhood experiences from a very young age. On the other hand, only physical abuse was associated with dementia among men (Table 3). The proportion of physical abuse was less than 8% for men with fewer than 2 adverse childhood experiences, but 45% for men with 3 or more adverse childhood experiences (eTable 2 in the Supplement). This may explain why having fewer than 2 adverse childhood experiences was not associated with dementia in men. Another explanation of sex difference is survival effect—that is, people who survive adverse circumstances earlier in life are a select group of hardy individuals. In a previous study of older people in Japan,38 we found that men with deprived childhood socioeconomic circumstances had a lower risk of death, but this was not true among women. It is possible that men with deprived childhood socioeconomic circumstances were less likely than women to be resistant to adversities such as wartime food shortages and infectious diseases and, hence, more likely to have died at younger ages. Therefore, in the context of this study, men who experienced several adverse childhood experiences died prematurely, and the association between adverse childhood experiences and dementia may have been underestimated among men. Further study is needed to elucidate the differential outcomes of adverse childhood experiences on dementia by sex.

    When analyzing each adverse childhood experience item separately, we found that physical abuse was significantly associated with dementia. Physical abuse could damage the brain,44 which could increase the risk of dementia. Although the association between parental mental illness and dementia was not significant, perhaps because of the small number of participants, the point estimates were high. Given that parental mental health disorders may be inheritable, this association is important and further research is needed.

    Limitations

    Several limitations to this study should be mentioned. First, because a cutoff point of the dementia scale in this study corresponded to a 16-point rating on the Mini-Mental State Examination,33 the onset of dementia may be underestimated. In a nationwide study45 estimating the prevalence of dementia in Japan, this cutoff point of the dementia scale did not cover 34% of dementia cases; however, most of these were mild cases of dementia. Second, we assessed adverse childhood experiences via retrospective assessment, which may induce recall biases. Previous meta-analyses46-48 reported that retrospective assessment of adverse childhood experiences overestimated actual adverse childhood experiences. However, we confirmed that the prevalence of psychological neglect was similar across each age cohort, and the prevalence of parental death was higher among the older age cohort.24 This is plausible because the older the participants were, the more likely their parents would have been involved in World War II. Thus, recall bias is not likely to affect accuracy of reporting. Third, we did not directly assess the experience of World War II. People who have severe war experiences may also have multiple adverse childhood experiences. Therefore, interpretation of the results should be done with caution, because the association between adverse childhood experiences and dementia may be altered by a severe war experience.

    Fourth, in addition to the 71% response rate, we were able to link to dementia data for 92% of participants, and 2276 people did not answer questions regarding adverse childhood experiences, so the generalizability of this study is somewhat weak. The characteristics of the nonparticipants in this survey were unavailable. However, comparisons of characteristics for whether they answered the questions regarding adverse childhood experiences revealed that the nonrespondents tended to be older and shorter, have lower socioeconomic status, and be unmarried compared with the respondents (eTable 4 in the Supplement). This suggests that our study sample lacked people who were vulnerable to dementia, which may have been linked to an underestimation of the association between adverse childhood experiences and dementia. Fifth, although the participants were older people without functional disabilities, which was defined as not being certified as eligible for benefits from the long-term care insurance, it may not rule out potential prevalent dementia cases at baseline. When assessed using the subjective cognitive function score,49 1% of participants had 3 cognitive complaints at baseline. Therefore, our study may include some people with dementia at baseline. Sixth, because the sample was limited to people aged 65 years and older who had not received a diagnosis of dementia, the association between adverse childhood experiences and early-onset dementia cannot be analyzed. It is possible that only healthier participants were included in this study, and the association of adverse childhood experiences with dementia may be underestimated.

    Conclusions

    This study found an association between adverse childhood experiences and late-life dementia onset longitudinally among older adults, using a large-scale population-based sample in Japan. These findings may not be generalizable to other generations and cultures. Further study is warranted to replicate the association of cumulative adverse childhood experiences and dementia in other settings, taking into consideration the mechanisms of sex difference.

    Back to top
    Article Information

    Accepted for Publication: December 12, 2019.

    Published: February 7, 2020. doi:10.1001/jamanetworkopen.2019.20740

    Open Access: This is an open access article distributed under the terms of the CC-BY License. © 2020 Tani Y et al. JAMA Network Open.

    Corresponding Author: Yukako Tani, PhD, Department of Global Health Promotion, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8519, Japan (tani.hlth@tmd.ac.jp).

    Author Contributions: Dr Tani had full access to all of the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.

    Concept and design: All authors.

    Acquisition, analysis, or interpretation of data: All authors.

    Drafting of the manuscript: Tani.

    Critical revision of the manuscript for important intellectual content: Fujiwara, Kondo.

    Statistical analysis: Tani, Fujiwara.

    Obtained funding: Tani, Fujiwara, Kondo.

    Administrative, technical, or material support: Tani, Kondo.

    Supervision: Fujiwara, Kondo.

    Conflict of Interest Disclosures: Dr Kondo reported receiving grants and nonfinancial support from NEC and grants from Ryobi Systems Company and Risol Seimi-No-Mori Corporation outside the submitted work. No other disclosures were reported.

    Funding/Support: The Japan Gerontological Evaluation Study was supported by KAKENHI grants JP15H01972, JP20319338, JP22390400, JP23243070, JP23590786, JP23790710, JP24140701, JP24390469, JP24530698, JP24653150, JP24683018, JP25253052, JP25870573, JP25870881, JP26882010, JP17K19794, and JP19K14029 from the Japan Society for the Promotion of Science; Health Labour Sciences research grants H28-Choju-Ippan-002, H26-Choju-Ippan-006, H25-Choju-Ippan-003, H25-Kenki-Wakate-015, H25-Irryo-Shitei-003[Fukkou], and H24-Junkanki[Seishu]-Ippan-007; Research and Development Grants for Longevity Science from Japan Agency for Medical Research and Development; grants 24-17 and 24-23 from the Research Funding for Longevity Sciences from National Center for Geriatrics and Gerontology; and grant J09KF00804 from the Japan Foundation for Aging and Health.

    Role of the Funder/Sponsor: The funders had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; and decision to submit the manuscript for publication.

    References
    1.
    Frankish  H, Horton  R.  Prevention and management of dementia: a priority for public health.  Lancet. 2017;390(10113):2614-2615. doi:10.1016/S0140-6736(17)31756-7PubMedGoogle ScholarCrossref
    2.
    Livingston  G, Sommerlad  A, Orgeta  V,  et al Dementia prevention, intervention, and care.  Lancet. 2017;390(10113):2673-2734. doi:10.1016/S0140-6736(17)31363-6PubMedGoogle ScholarCrossref
    3.
    Stern  Y.  Cognitive reserve in ageing and Alzheimer’s disease.  Lancet Neurol. 2012;11(11):1006-1012. doi:10.1016/S1474-4422(12)70191-6PubMedGoogle ScholarCrossref
    4.
    Kaplan  GA, Turrell  G, Lynch  JW, Everson  SA, Helkala  EL, Salonen  JT.  Childhood socioeconomic position and cognitive function in adulthood.  Int J Epidemiol. 2001;30(2):256-263. doi:10.1093/ije/30.2.256PubMedGoogle ScholarCrossref
    5.
    Zeki Al Hazzouri  A, Haan  MN, Kalbfleisch  JD, Galea  S, Lisabeth  LD, Aiello  AE.  Life-course socioeconomic position and incidence of dementia and cognitive impairment without dementia in older Mexican Americans: results from the Sacramento area Latino study on aging.  Am J Epidemiol. 2011;173(10):1148-1158. doi:10.1093/aje/kwq483PubMedGoogle ScholarCrossref
    6.
    Hart  H, Rubia  K.  Neuroimaging of child abuse: a critical review.  Front Hum Neurosci. 2012;6:52. doi:10.3389/fnhum.2012.00052PubMedGoogle ScholarCrossref
    7.
    Bick  J, Nelson  CA.  Early adverse experiences and the developing brain.  Neuropsychopharmacology. 2016;41(1):177-196. doi:10.1038/npp.2015.252PubMedGoogle ScholarCrossref
    8.
    Felitti  VJ, Anda  RF, Nordenberg  D,  et al.  Relationship of childhood abuse and household dysfunction to many of the leading causes of death in adults: the Adverse Childhood Experiences (ACE) Study.  Am J Prev Med. 1998;14(4):245-258. doi:10.1016/S0749-3797(98)00017-8PubMedGoogle ScholarCrossref
    9.
    Danese  A, Moffitt  TE, Harrington  H,  et al.  Adverse childhood experiences and adult risk factors for age-related disease: depression, inflammation, and clustering of metabolic risk markers.  Arch Pediatr Adolesc Med. 2009;163(12):1135-1143. doi:10.1001/archpediatrics.2009.214PubMedGoogle ScholarCrossref
    10.
    Ritchie  K, Jaussent  I, Stewart  R,  et al.  Adverse childhood environment and late-life cognitive functioning.  Int J Geriatr Psychiatry. 2011;26(5):503-510. doi:10.1002/gps.2553PubMedGoogle ScholarCrossref
    11.
    Richards  M, Wadsworth  ME.  Long term effects of early adversity on cognitive function.  Arch Dis Child. 2004;89(10):922-927. doi:10.1136/adc.2003.032490PubMedGoogle ScholarCrossref
    12.
    Whalley  LJ, Staff  RT, Murray  AD, Deary  IJ, Starr  JM.  Genetic and environmental factors in late onset dementia: possible role for early parental death.  Int J Geriatr Psychiatry. 2013;28(1):75-81. doi:10.1002/gps.3792PubMedGoogle ScholarCrossref
    13.
    Norton  MC, Smith  KR, Ostbye  T,  et al Early parental death and remarriage of widowed parents as risk factors for Alzheimer disease: the Cache County study.  Am J Geriatr Psychiatry. 2011;19(9):814-824. doi:10.1111/j.1532-5415.2010.02806.xPubMedGoogle ScholarCrossref
    14.
    Persson  G, Skong  I.  A prospective population study of psychosocial risk factors for late onset dementia.  Int J Geriatr Psychiatry. 1996;11:15-22. doi:10.1002/(SICI)1099-1166(199601)11:1<15::AID-GPS262>3.0.CO;2-5Google ScholarCrossref
    15.
    Radford  K, Delbaere  K, Draper  B,  et al Childhood stress and adversity is associated with late-life dementia in Aboriginal Australians.  Am J Geriatr Psychiatry. 2017;25(10):1097-1106. doi:10.1016/j.jagp.2017.05.008PubMedGoogle ScholarCrossref
    16.
    Korten  NC, Penninx  BW, Pot  AM, Deeg  DJ, Comijs  HC.  Adverse childhood and recent negative life events: contrasting associations with cognitive decline in older persons.  J Geriatr Psychiatry Neurol. 2014;27(2):128-138. doi:10.1177/0891988714522696PubMedGoogle ScholarCrossref
    17.
    Rosenman  S, Rodgers  B.  Childhood adversity in an Australian population.  Soc Psychiatry Psychiatr Epidemiol. 2004;39(9):695-702. doi:10.1007/s00127-004-0802-0PubMedGoogle ScholarCrossref
    18.
    Podcasy  JL, Epperson  CN.  Considering sex and gender in Alzheimer disease and other dementias.  Dialogues Clin Neurosci. 2016;18(4):437-446.PubMedGoogle Scholar
    19.
    Currie  J, Widom  CS.  Long-term consequences of child abuse and neglect on adult economic well-being.  Child Maltreat. 2010;15(2):111-120. doi:10.1177/1077559509355316PubMedGoogle ScholarCrossref
    20.
    Haatainen  KM, Tanskanen  A, Kylmä  J,  et al.  Gender differences in the association of adult hopelessness with adverse childhood experiences.  Soc Psychiatry Psychiatr Epidemiol. 2003;38(1):12-17. doi:10.1007/s00127-003-0598-3PubMedGoogle ScholarCrossref
    21.
    Thompson  MP, Kingree  JB, Desai  S.  Gender differences in long-term health consequences of physical abuse of children: data from a nationally representative survey.  Am J Public Health. 2004;94(4):599-604. doi:10.2105/AJPH.94.4.599PubMedGoogle ScholarCrossref
    22.
    MacMillan  HL, Fleming  JE, Streiner  DL,  et al.  Childhood abuse and lifetime psychopathology in a community sample.  Am J Psychiatry. 2001;158(11):1878-1883. doi:10.1176/appi.ajp.158.11.1878PubMedGoogle ScholarCrossref
    23.
    World Health Organization.  World Report on Ageing and Health. Geneva, Switzerland: World Health Organization; 2015.
    24.
    Amemiya  A, Fujiwara  T, Murayama  H, Tani  Y, Kondo  K.  Adverse childhood experiences and higher-level functional limitations among older Japanese people: results from the JAGES study.  J Gerontol A Biol Sci Med Sci. 2018;73(2):261-266. doi:10.1093/gerona/glx097PubMedGoogle ScholarCrossref
    25.
    Kondo  K, Rosenberg  M.  Advancing Universal Health Coverage Through Knowledge Translation for Healthy Ageing: Lessons Learnt From the Japan Gerontological Evaluation Study. Geneva, Switzerland: World Health Organization; 2018.
    26.
    Kondo  K.  Progress in aging epidemiology in Japan: the JAGES Project.  J Epidemiol. 2016;26(7):331-336. doi:10.2188/jea.JE20160093PubMedGoogle ScholarCrossref
    27.
    Tamiya  N, Noguchi  H, Nishi  A,  et al.  Population ageing and wellbeing: lessons from Japan’s long-term care insurance policy.  Lancet. 2011;378(9797):1183-1192. doi:10.1016/S0140-6736(11)61176-8PubMedGoogle ScholarCrossref
    28.
    Tani  Y, Suzuki  N, Fujiwara  T, Hanazato  M, Kondo  K.  Neighborhood food environment and dementia incidence: the Japan Gerontological Evaluation Study Cohort Survey.  Am J Prev Med. 2019;56(3):383-392. doi:10.1016/j.amepre.2018.10.028PubMedGoogle ScholarCrossref
    29.
    Ministry of Health, Labour, and Welfare. Textbook for expert investigators concerning a certification of needed long-term care, revised edition, 2009 [in Japanese]. https://www.mhlw.go.jp/file/06-Seisakujouhou-12300000-Roukenkyoku/0000077237.pdf. Published 2018. Accessed October 23, 2017.
    30.
    Hikichi  H, Kondo  K, Takeda  T, Kawachi  I.  Social interaction and cognitive decline: results of a 7-year community intervention.  Alzheimers Dement (N Y). 2016;3(1):23-32.PubMedGoogle Scholar
    31.
    Hikichi  H, Aida  J, Kondo  K,  et al.  Increased risk of dementia in the aftermath of the 2011 Great East Japan earthquake and tsunami.  Proc Natl Acad Sci USA. 2016;113(45):E6911-E6918. doi:10.1073/pnas.1607793113PubMedGoogle ScholarCrossref
    32.
    Tomata  Y, Sugiyama  K, Kaiho  Y,  et al.  Green tea consumption and the risk of incident dementia in elderly Japanese: the Ohsaki Cohort 2006 Study.  Am J Geriatr Psychiatry. 2016;24(10):881-889. doi:10.1016/j.jagp.2016.07.009PubMedGoogle ScholarCrossref
    33.
    Hisano  S.  The relationship between Revised Hasegawa Dementia Scale (HDS-R), Mini-Mental State Examination (MMSE), and Bed-Fast Scale, Dementia Scale [in Japanese].  Jpn J Geriatr Psychiatry. 2009;20:883-891.Google Scholar
    34.
    Saito  T, Murata  C, Saito  M, Takeda  T, Kondo  K.  Influence of social relationship domains and their combinations on incident dementia: a prospective cohort study.  J Epidemiol Community Health. 2018;72(1):7-12. doi:10.1136/jech-2017-209811PubMedGoogle ScholarCrossref
    35.
    Matsuyama  Y, Fujiwara  T, Aida  J,  et al.  Experience of childhood abuse and later number of remaining teeth in older Japanese: a life-course study from Japan Gerontological Evaluation Study project.  Community Dent Oral Epidemiol. 2016;44(6):531-539. doi:10.1111/cdoe.12246PubMedGoogle ScholarCrossref
    36.
    Silventoinen  K.  Determinants of variation in adult body height.  J Biosoc Sci. 2003;35(2):263-285. doi:10.1017/S0021932003002633PubMedGoogle ScholarCrossref
    37.
    Fujiwara  T, Kondo  K, Shirai  K, Suzuki  K, Kawachi  I.  Associations of childhood socioeconomic status and adulthood height with functional limitations among Japanese older people: results from the JAGES 2010 Project.  J Gerontol A Biol Sci Med Sci. 2014;69(7):852-859. doi:10.1093/gerona/glt189PubMedGoogle ScholarCrossref
    38.
    Tani  Y, Kondo  N, Nagamine  Y,  et al.  Childhood socioeconomic disadvantage is associated with lower mortality in older Japanese men: the JAGES cohort study.  Int J Epidemiol. 2016;45(4):1226-1235. doi:10.1093/ije/dyw146PubMedGoogle Scholar
    39.
    Wada  T, Ishine  M, Kita  T, Fujisawa  M, Matsubayashi  K.  Depression screening of elderly community-dwelling Japanese.  J Am Geriatr Soc. 2003;51(9):1328-1329. doi:10.1046/j.1532-5415.2003.514207.xPubMedGoogle Scholar
    40.
    National Institute of Population and Social Security Research. The 15th Japanese National Fertility Survey [in Japanese]. http://www.ipss.go.jp/ps-doukou/j/doukou15/gaiyou15html/NFS15G_html09.html. Published 2017. Accessed November 19, 2019.
    41.
    Kuh  D, Ben-Shlomo  Y, Lynch  J, Hallqvist  J, Power  C.  Life course epidemiology.  J Epidemiol Community Health. 2003;57(10):778-783. doi:10.1136/jech.57.10.778PubMedGoogle ScholarCrossref
    42.
    Statistics Bureau, Ministry of Internal Affairs and Communications. Labour force survey FY 1980 [in Japanese]. https://www.e-stat.go.jp/stat-search/files?page=1&layout=datalist&toukei=00200531&tstat=000000110001&cycle=1&year=19800&month=11010303&tclass1=000001062127&tclass2=000001062128&result_back=1. Published 2013. Accessed June 23, 2019.
    43.
    Minamoto  J.  A study of “dansonjohi”: predominance of men over women in modern Japan [in Japanese].  Bull Inst Hum Rights Stud. 2015;70:1-48.Google Scholar
    44.
    Tomoda  A, Suzuki  H, Rabi  K, Sheu  YS, Polcari  A, Teicher  MH.  Reduced prefrontal cortical gray matter volume in young adults exposed to harsh corporal punishment.  Neuroimage. 2009;47(2)(suppl):T66-T71. doi:10.1016/j.neuroimage.2009.03.005PubMedGoogle ScholarCrossref
    45.
    Asada  T. Prevalence of dementia in urban areas and functional disability in dementia for FY2011-2012 [in Japanese]. http://www.tsukuba-psychiatry.com/wp-content/uploads/2013/06/H24Report_Part1.pdf. Published 2013. Accessed December 17, 2019.
    46.
    Baldwin  JR, Reuben  A, Newbury  JB, Danese  A.  Agreement between prospective and retrospective measures of childhood maltreatment: a systematic review and meta-analysis.  JAMA Psychiatry. 2019;76(6):584-593. doi:10.1001/jamapsychiatry.2019.0097PubMedGoogle ScholarCrossref
    47.
    Reuben  A, Moffitt  TE, Caspi  A,  et al.  Lest we forget: comparing retrospective and prospective assessments of adverse childhood experiences in the prediction of adult health.  J Child Psychol Psychiatry. 2016;57(10):1103-1112. doi:10.1111/jcpp.12621PubMedGoogle ScholarCrossref
    48.
    Hardt  J, Rutter  M.  Validity of adult retrospective reports of adverse childhood experiences: review of the evidence.  J Child Psychol Psychiatry. 2004;45(2):260-273. doi:10.1111/j.1469-7610.2004.00218.xPubMedGoogle ScholarCrossref
    49.
    Tomata  Y, Sugiyama  K, Kaiho  Y, Sugawara  Y, Hozawa  A, Tsuji  I.  Predictive ability of a simple subjective memory complaints scale for incident dementia: evaluation of Japan’s national checklist, the “Kihon Checklist”.  Geriatr Gerontol Int. 2017;17(9):1300-1305. doi:10.1111/ggi.12864PubMedGoogle ScholarCrossref
    ×