Copyright 1999 American Medical Association. All Rights Reserved. Applicable FARS/DFARS Restrictions Apply to Government Use.1999
American Indians and Alaska Natives have the highest suicide rates of all ethnic groups in the United States, and suicide is the second leading cause of death for American Indian and Alaska Native youth.
To identify risk and protective factors associated with suicide attempts among native male and female adolescents.
The 1990 National American Indian Adolescent Health Survey.
Schools of reservation communities in 8 Indian Health Service areas.
Eleven thousand six hundred sixty-six 7th-through 12th-grade American Indian and Alaska native youth.
Main Outcome Measures
Responses were compared among adolescents with and without a self-reported history of attempted suicide. Independent variables included measures of community, family, and individual characteristics. Separate analyses were conducted for boys and girls.
Ever attempting suicide was reported by 21.8% of girls and 11.8% of boys. By logistic regression done on boys and girls separately, suicide attempts were associated with friends or family members attempting or completing suicide; somatic symptoms; physical or sexual abuse; health concerns; using alcohol, marijuana, or other drugs; a history of being in a special education class; treatment for emotional problems; gang involvement; and gun availability. For male and female youth, discussing problems with friends or family, emotional health, and connectedness to family were protective against suicide attempts. The estimated probability of attempting suicide increased dramatically as the number of risk factors to which an adolescent was exposed increased; however, increasing protective factors was more effective at reducing the probability of a suicide attempt than was decreasing risk factors.
A history of attempted suicide was associated with several risk and protective factors. In addition to targeting youth at increased risk, preventive efforts should include promotion of protective factors in the lives of all youth in this population.
SUICIDE IS the third leading cause of death for 15- to 24-year-olds in the United States. Incidence rates have nearly tripled, from 4.5 per 100,000 in 1950 to 13 per 100,000 in 1992.1 Of all ethnic groups in the United States, American Indians and Alaska Natives have the highest suicide rates. The suicide rate for American Indian and Alaska Native youth from 1991 to 1993 was 31.7 per 100,000, more than twice the national rate for all youth, making suicide the second leading cause of death for American Indian and Alaska Native youth.1
The most important correlate for youth suicide is a previous attempt. It is estimated that there are about 13 suicide attempts for every completed suicide in the American Indian population.2 Furthermore, it is estimated that more than 40% of adolescents who complete suicide have made previous attempts, and attempters are 20 to 50 times more likely to complete suicide than peers without a history of attempts.3,4 Suicide attempts have been shown to be associated with depression,5- 8 substance use,9- 11 loss of a family member or friend to suicide,12,13 availability of firearms,14,15 female sex,10,11 and a history of physical or sexual abuse.10,16,17 Some of the same risk factors for suicide attempts among adolescents in the general population have been found for American Indian and Alaska Native youth populations.5,6,10
The high rates of suicide among American Indian and Alaska Native youth warrant further study to identify modifiable factors and culturally appropriate interventions that can successfully nurture resilience in this high-risk population. The purpose of this study was to identify risk and protective factors for suicide attempts in a large sample of American Indian and Alaska Native youth living in reservation communities. We examined the individual and cumulative effects of personal, family, and community factors on suicide attempts by male and female adolescents, as well as the interaction between risk and protective factors.
Data were obtained from the 1990 National American Indian Adolescent Health Survey, administered to 7th- through 12th-grade American Indian and Alaska Native youth attending schools of reservation communities serviced by the Indian Health Service throughout the United States. The 162-item survey is a comprehensive assessment of adolescent risk behaviors and environments, resiliency factors, and health outcomes. The questionnaire is designed at the fifth-grade reading level, with a completion time of approximately 1 hour. Survey development and administration, cleaning and editing procedures for the data, and psychometric properties of scales and indices have been described elsewhere.18- 21 This national data set of American Indian youth is the largest of its kind compiled to date.
The sample of students came from reservation-based schools in Alaska, Arizona, California, Minnesota, Montana, New Mexico, South Dakota, and Tennessee.18 The 13,454 youths surveyed represented approximately 20% of the eligible students in the geographic areas participating in the survey.
A history of ever attempting suicide was assessed with the question: "Have you ever tried to kill yourself?" Of the 13,310 survey respondents ages 12 to 18 years, 11,666 (88%) answered the question about suicide attempts; 661 male students and 1323 female students reported a history of attempting suicide.
Adolescents reporting ever attempting suicide were compared with those who indicated that they had never attempted suicide. The independent variables fell into 3 broad categories: community, family, and personal factors (Table 1). The independent variables were theoretically derived from a resiliency framework, positing that adolescents' vulnerability to health-jeopardizing outcomes is affected by both the number and nature of stressors as well as the presence of buffering, protective factors. Adverse or successful outcomes are described as emanating from the interplay of individual, familial, and environmental characteristics.22- 31
All analyses were conducted separately for boys and girls. Bivariate relationships between a history of attempting suicide and potential risk and protective factors were examined using χ2 tests. Logistic regression was used to assess the effect of each factor on ever attempting suicide after controlling for other factors.
To determine which variables to enter into the logistic models, a stepwise, chunkwise regression was performed.32 The variables in each of the 3 categories of community, family, and personal factors were subjected to a forward stepwise process by the PROC LOGISTIC procedure (SAS Inc, Cary, NC), while forcing the variables in the remaining 2 categories as well as age and the substance use variables into the model. This process was repeated for each of the 3 categories. The variables that survived these chunkwise selection procedures at P<.15 were entered into the final stepwise models. Significant variables (P<.05) were retained in the final models.
Interaction terms were evaluated for the variables in the final models. None of the interaction terms were both statistically and substantively significant.
We also used the logistic models to predict the probabilities of attempting suicide for adolescents in the population with increasing numbers of risk factors and protective factors. Thus, we calculated the estimated probabilities of a suicide attempt when there were 0, 1, 2, or 3 protective factors present, in combination with the presence of 0, 1, or 2 environmental risk factors. Additionally, for each of these combinations, we calculated the estimated probabilities of a suicide attempt when substance use was either present or absent. For ease of interpretation, we simplified the model by including only the most powerful risk and protective factors. To calculate the risk of a suicide attempt for adolescents with various numbers of risk and protective factors, rather than for specific risk and protective factors, we used weights in the probability equation that were the arithmetic average of the parameter estimates.
One or more suicide attempts were reported by 21.8% of girls (1323 of 6079) and 11.8% of boys (661 of 5587). Community factors significantly associated with an increased or diminished likelihood of ever attempting suicide among male and female youth in bivariate analyses are shown in Table 2. Family factors are described in Table 3, personal factors in Table 4.
Logistic regression models were then developed for boys and girls (Table 5) using 3 stepwise, chunkwise regression analyses controlling for the effects of age, to determine which community, family, and personal factors to enter into the final multivariate analyses.
The strongest association with a history of attempted suicide for both male and female respondents was having a friend attempt or complete suicide (odds ratio, 3.80 for boys, 4.52 for girls). Other risk factors significantly associated with a history of attempted suicide by both boys and girls after controlling for other factors in the models were somatic symptoms, such as headaches and stomach problems, a history of sexual or physical abuse, having a family member attempt or complete suicide, having health concerns, frequent alcohol or marijuana use, or ever using any other drugs. Gang involvement and a history of being treated for emotional problems were associated with a past suicide attempt by male adolescents, and knowing where to get a gun and a history of being in a special education class were associated with a past suicide attempt by female adolescents after controlling for other factors.
Several factors significantly reduced the odds of attempting suicide. Both male and female adolescents who reported that they discussed problems with friends or family members, were in good emotional health, or had a sense of connectedness with family were much less likely to report a past suicide attempt. Girls with a nurse or clinic in their school were also less likely to report a past suicide attempt.
We then predicted the probabilities of attempting suicide for boys and girls in the population using various combinations of risk and protective factors (Table 6). Only 1% of both male and female adolescents with the 3 protective factors (discussing problems with friends or family members, emotional health, and family connectedness) and none of the 3 risk factors (having a friend or family member attempt or complete suicide, experiencing physical or sexual abuse, and at least weekly wine or beer use, monthly hard liquor use, or use of any marijuana or other drugs) would be expected to attempt suicide. In contrast, 81% of girls and 75% of boys with the 3 risk factors and none of the 3 protective factors in the model would be expected to attempt suicide. The likelihood of attempting suicide increased dramatically as the number of risk factors to which an adolescent was exposed increased, up to a 14-fold increase with all 3 risk factors present; however, for both male and female adolescents, adding protective factors was equally or more effective than decreasing risk factors in terms of reducing suicide risk. The risk of having a low degree of protection was particularly dramatic among girls; adolescents with none of the risk factors but also none of the protective factors were nearly twice as likely to attempt suicide as adolescents with all 3 of the risk factors but also all 3 of the protective factors (27% vs 14%).
We found that 22% of girls and 12% of boys in this national sample of American Indian and Alaska Native youth reported ever attempting suicide. The 1995 national, school-based Youth Risk Behavior Survey indicates that 12% of girls and 6% of boys attempted suicide during the preceding 12 months.33 In the present sample of American Indian and Alaska Native youth, 14% of girls and 8% of boys reported attempting suicide in the preceding 12 months. Our study showed that suicide attempts among American Indian and Alaska Native youth are associated with community, family, and personal risk and protective factors. Family connectedness, discussing problems with friends or family members, and emotional health markedly lowered the risk of suicide attempts among adolescents, including those with and without identified risk factors.
It should be noted that our data are based on a large-scale convenience sample of American Indian adolescents from nonurban areas serviced by the Indian Health Service. Therefore, the sample cannot be regarded as statistically representative of urban or rural American Indian adolescents. Regional and tribal variations in rates of suicide and suicide attempts among American Indian and Alaska Native adolescents have been found.2,18 Since the sample was school-based, some of the most high-risk youth, those who are frequently absent or who have dropped out of school, may have been excluded. We also could not control for or analyze socioeconomic factors in the present analyses due to the absence of measures of familial socioeconomic status; however, the National American Indian Adolescent Health Survey is the largest and most comprehensive database available on rural, reservation-based American Indian and Alaska Native youth, and there is little reason to believe that a representative sample of school-based, rural American Indian adolescents would yield findings substantially different from those presented here.18
There are dramatic differences in suicidal behavior between male and female adolescents. Girls attempt suicide much more often than boys, but nearly 5 times more adolescent boys than girls complete suicide. To our knowledge, this is the first study to examine factors associated with suicide attempts separately for male and female American Indian and Alaska Native adolescents. Most of the factors that showed significant associations with suicide attempts in the multivariate models were the same for male and female youth, with a few notable exceptions: gang involvement and a history of being treated for emotional problems were significant risk factors for boys, and knowing where to get a gun and a history of being in a special education class were significant risk factors for girls. In addition, having a nurse or clinic in school was protective only for girls.
The most powerful risk factor for a past suicide attempt among male and female youth in the present study was having a friend who attempted or completed suicide. Exposure to the suicide of a friend or acquaintance has been associated with a markedly increased incidence of new-onset major depression.12 Depression may occur as a complication of bereavement and is more likely to develop in youths who had a close relationship with the victim, spoke to the victim on the day of the suicide, viewed the scene of death, or have a personal or family history of depression.34 Friends of adolescent suicide victims may also develop posttraumatic stress disorder.12,35 The high rates of suicide and suicide attempts among American Indian and Alaska Native youth are underscored in the present study by the number of respondents who indicated that they had a friend who had attempted suicide (28% [3307/11,826]) or completed suicide (12% [1443/11,817]). Given the degree of exposure to a friend's suicidal behavior among American Indian and Alaska Native youth as well as this variable's strong association with suicide attempts, routine screening of youth in this population for exposure to suicidal behavior and the development of depression should be considered so that appropriate treatment can be given.
Having a family member who attempted or completed suicide was also a significant risk factor for a past suicide attempt among both male and female adolescents. Overall, 4.2% (496/11,803) of adolescents reported a suicide attempt or completion by a family member. Previous studies have shown an increased rate of suicide and suicide attempts in the relatives of suicide victims.3,36 This familial aggregation of suicide attempts persists even after adjusting for differences in familial rates of psychiatric disorders,13 yet other studies using prospective designs have found that suicidal behavior in families was not predictive of suicide attempts in children and adolescents.37,38 Brent et al39 reported that adolescent siblings of teenage suicide victims were at a 7-fold increased risk for developing a major depression within 6 months after a sibling's death compared with controls unexposed to suicide; however, in contrast to unrelated friends of suicide victims, siblings of suicide victims did not show an increased risk for recurrent depression during a 2- to 3-year follow-up period.40 Familial transmission of suicidal behavior may involve genetic and nongenetic mechanisms.
Alcohol, marijuana, and other drug use was associated with suicide attempts by male and female youth. Previous studies of Native American10,41 and other11,42- 44 youth have also found this association between substance use and completed and attempted suicides. It is unclear if the association is causal or rather if substance abuse is secondary to another factor, such as depression or hopelessness.9 In the present study, alcohol, marijuana, and other drug use remained significant even when the effects of other factors, including a measure of emotional health, were taken into account. The cross-sectional nature of the data, however, precludes demonstration of a cause-effect relationship among variables.
Our finding that past sexual and physical abuse are risk factors for suicide attempts among male and female youth is consistent with the results of other studies.10,16,17,45 We found that experiencing sexual abuse is a stronger predictor of attempting suicide for male youth than for female youth in this population. Studies in other adolescent populations have shown more emotional and behavioral problems, including suicidality,17,46 as well as a greater likelihood of perpetration of sexual violence47 among sexually abused boys than girls. Our culture's emphasis on male strength and control may provide strong disincentives for male youths to disclose sexual abuse and obtain needed help.
In our study, we found that having somatic symptoms, including headaches, breathing problems, stomach problems, allergies, and nerves, and being concerned about one's health were risk factors for attempting suicide. Grossman et al10 found that a self-perception of poor general health was associated with a history of suicide attempts among Navajo adolescents. Associations have been found between somatic symptoms and depression, anxiety, and suicide attempts in other adolescent populations,48- 50 and children with chronic physical conditions have been shown to be at higher risk for mental health problems.51 Despite these findings, adolescents with somatic symptoms are infrequently screened for depression in the acute care setting.52 Slap et al50 found that physicians caring for adolescents seldom recognize histories of previous suicidal behavior in their patients. Health care providers should routinely screen adolescents with multiple or functionally limiting physical symptoms for depression and ask about suicidal ideation or behavior, regardless of whether the symptoms are associated with organic disease.
Numerous studies have demonstrated a relationship between the availability of guns and adolescent suicide.14,15,41,44,53,54 Our study of American Indian and Alaska Native youth found an association between gun availability and suicide attempts among female adolescents. Resnick et al55 reported an association between easy availability of a gun at home and suicidal ideation or attempts for older adolescents in a nationally representative sample of youth. Particularly among the 5% to 10% of adolescent suicide victims without apparent psychiatric illness, restricting the availability and accessibility of firearms has been identified as the best strategy to prevent suicide.14,15
Discussing problems with friends or family members, emotional health, and perceived connectedness to family emerged as the significant protective factors regarding past suicide attempts for both male and female adolescents. The protective function of family connectedness in the lives of youth for suicidal behavior10,56,57 and other risk behaviors19,55 has been described. Studies have also found that poor parent-child communication is a risk factor for adolescent suicide,58 and not talking about suicidal ideation is associated with suicide attempts among adolescents.59 Psychopathology, primarily depression, has been found to characterize most adolescent suicides.8,60,61
We found that increasing the number of the 3 protective factors—discussing problems with friends or family, emotional health, and family connectedness—was more effective at reducing the probability of a suicide attempt than was decreasing risk factors. Furthermore, even among adolescents without any of the risk factors included in the model, the presence of these protective factors markedly decreased the risk of a suicide attempt. While yet to be empirically demonstrated for all youth, these findings raise important considerations for prevention programming. Research is needed to confirm the generalizability of these findings to other populations. In addition, programmatic and policy responses to the problem of adolescent suicidal behavior should focus on promoting these protective factors in the lives of young people living in high-risk environments. Health care professionals have a responsibility to inquire about emotional health and interactions with family and friends, particularly regarding communication about problems, and to educate parents early about the importance of family integration and communication. Referrals to mental health and social service providers should be made as appropriate.
Accepted for publication October 8, 1998.
This study was supported by grant R49/CCR511638-03-2 from the National Center for Injury Prevention and Control, Centers for Disease and Control and Prevention, Atlanta, Ga (Drs Resnick, Borowsky, Blum, and Ireland).
The contents of this article are solely the responsibility of the authors and do not necessarily represent the official views of the National Center for Injury Prevention and Control.
Corresponding author: Iris Wagman Borowsky, MD, PhD, Division of General Pediatrics and Adolescent Health, Box 721 FUMC, 420 Delaware St SE, Minneapolis, MN 55455 (e-mail: email@example.com).
Editor's Note: The thing I like best about this large study is that it shows that accentuating the positive (increasing protective factors) is more effective than "decentuating" the negative (decreasing risk factors). That seems much more hopeful to me.—Catherine D. DeAngelis, MD
Borowsky IW, Resnick MD, Ireland M, Blum RW. Suicide Attempts Among American Indian and Alaska Native YouthRisk and Protective Factors. Arch Pediatr Adolesc Med. 1999;153(6):573-580. doi:10.1001/archpedi.153.6.573