To examine young adult outcomes in a nationally representative US cohort of young adults growing up with a chronic illness.
Secondary analysis of nationally representative data from wave III (in 2001) of the National Longitudinal Study of Adolescent Health.
The analytic sample comprised 13 236 young adults aged 18 to 28 years at wave III.
Self-report of a chronic physical illness (asthma, cancer, diabetes mellitus, or epilepsy) in adolescence. Respondents with asthma or nonasthmatic chronic illness (cancer, diabetes mellitus, or epilepsy) were compared with individuals without these conditions.
Main Outcome Measures
Self-report of high school graduation, ever having employment, currently having employment, living with a parent/guardian, and ever receiving public assistance.
Three percent of young adults had nonasthmatic chronic illness (cancer, diabetes, or epilepsy), and 16.0% had asthma. Most young adults with chronic illness graduated high school (81.3%) and currently had employment (60.4%). However, compared with healthy young adults, those with nonasthmatic chronic illness were significantly less likely to graduate high school, ever have had employment, or currently have employment and were more likely to receive public assistance. Compared with young adults with asthma, those with nonasthmatic chronic illness again had significantly worse young adult outcomes on all measures.
Most young adults growing up with a chronic illness graduate high school and have employment. However, these young adults are significantly less likely than their healthy peers to achieve these important educational and vocational milestones.
Estimates of the prevalence of children with chronic health conditions vary depending on the operationalization of the concept. Although less than 1% of children are defined as medically fragile, requiring technological assistance, 44% of children have some type of chronic condition, including mild seasonal allergies.1 In the United States, despite the variation in estimates, it is generally accepted that as many as 12% of children have special health care needs, including physical and emotional problems.1,2
With improved medical care during the past 40 years, most children with chronic illnesses survive into adulthood.3,4 Each year, approximately 500 000 children with special health care needs turn 18 years old.3 The successful transition of such young adults from childhood to adulthood is a concern of the Maternal Child Health Bureau and is included among the Healthy People 2010 core outcomes.3,5 Because chronic illness is associated with missing school and may also limit participation in social activities, chronic illness may negatively affect adult outcomes relevant to transition. Despite this possibility, little is known regarding the educational, vocational, and financial outcomes of young adults growing up with chronic illness, especially as investigated in longitudinal designs.
European studies,6- 8 mostly cross-sectional, have found that compared with healthy control individuals, young adults growing up with various types of chronic illnesses have lower educational and vocational attainment. However, in a longitudinal study from Finland,9,10 no differences were found in similar outcomes. In the United States, previous research11- 13 suggests relationships between chronic illness in childhood and higher rates of unemployment, receipt of Supplemental Security Income (SSI), and lower income, but findings regarding the effect of childhood chronic illness on high school graduation rates are inconsistent.
A major limitation of previous research is the inclusion of young adults whose chronic illness was seasonal allergies or asthma of uncertain severity. The inclusion of seasonal allergies or asthma of uncertain severity with more serious conditions reflects a noncategorical approach to childhood chronic illness, which is based on the assumption that the effects of chronic illness are similar across disease categories. The noncategorical approach is well accepted; however, analytically combining common conditions with varying levels of severity, such as asthma and seasonal allergies, with more severe conditions may obscure the effects of more severe childhood chronic illness.1,14- 16
This study examines 4 young adult outcomes that may be associated with childhood chronic illness in participants in the National Longitudinal Study of Adolescent Health (Add Health), a nationally representative US sample. We consider the following outcomes: high school graduation, employment history, current living situation, and receipt of public assistance. Based on previous literature, we hypothesize that young adults with chronic illness other than asthma have lower rates of high school graduation and employment and are more likely to live with their parent/guardian and to receive financial support from public programs. We also expect that young adults who report having asthma (severity not known) have outcomes similar to those of young adults without chronic illness because much of this group will likely have mild asthma.
We used data from waves I and III of the Add Health contractual data set. Add Health is a nationally representative sample of US adolescents enrolled in grades 7 through 12 in the 1994-1995 school year (wave I). More than 90 000 children and adolescents in 132 schools participated in the wave I in-school survey, with 20 745 respondents (aged 12-19 years) also completing subsequent in-depth home interviews in the 1994-1995 school year. Wave III follow-up interviews (n = 15 170) were conducted approximately 7 years after wave I, in 2001, with a 77% response rate. As previously reported,17 total bias related to attrition is low (<1%). More information regarding sampling procedures and study design can be found elsewhere.18 Inclusion criteria for the present analysis were participation in waves I and III (n = 14 322) and complete data on all variables of interest (n = 13 236). Data regarding socioeconomic status and race/ethnicity are drawn from wave I; the remainder of the measures are based on wave III.
At wave III, when respondents were aged 18 to 28 years, respondents were asked whether they had ever been diagnosed as having asthma, cancer, diabetes mellitus, or epilepsy; no other childhood chronic illnesses were asked about in the survey. Respondents who reported having asthma only were included in the asthma group; respondents who reported at least 1 of the other illnesses (regardless of whether they also had asthma) were included in the nonasthmatic chronic illness group. All other respondents were included in the healthy (no chronic illness) group. It was not possible to separate those with mild asthma from those with more severe asthma, so this heterogeneous group was treated as a separate group. For analysis, dummy variables were created to indicate asthma, nonasthmatic chronic illness, and healthy (reference). A dichotomous variable was also created to compare the healthy group with participants with any chronic illness, including asthma.
Respondents were coded as high school graduates (1) if they reported having a high school diploma or a GED (general equivalency diploma) and as not high school graduates (0) if they had neither. We included 2 indicators of vocational status: ever having had full- or part-time employment and having current full- or part-time employment. Each was coded as a dichotomous variable (1 = yes and 0 = no).
Several dichotomous economic outcomes were examined: currently receiving support in the form of food stamps from the Supplemental Nutrition Assistance Program (SNAP) and currently receiving disability insurance/workers' compensation/unemployment benefits or SSI (1 = yes and 0 = no). In addition, living situation was assessed based on a household roster by grouping respondents who currently lived with a parent/guardian (1) separately from those in other living situations (0).
All analyses included controls for factors that could independently contribute to young adult outcomes: socioeconomic status of family of origin, race/ethnicity, sex, and age. Socioeconomic status was based on highest educational level for either parent/guardian as reported by the child/adolescent at wave I; dummy variables were created to code for less than high school, high school graduate, some college, college graduate, and schooling beyond college, with less than high school as the reference category. Race/ethnicity was based on wave I self-report and was divided into non-Hispanic white, non-Hispanic black, Hispanic, and other, with non-Hispanic white as the reference category. Age at wave III was kept as a continuous variable. Sex was coded as male (0) or female (1).
Bivariate associations between outcome variables and illness status were examined first across all 3 groups and then between groups using the χ2 test. Multivariable Poisson regression was used to calculate risk ratios for dichotomous outcomes, controlling for sex, age, race/ethnicity, and parent/guardian educational level.19 Multivariate analyses were conducted in multiple steps. In model 1, the nonasthmatic chronic illness and asthma groups were each compared separately with the healthy group. In model 2, the nonasthmatic chronic illness group was compared with the asthma group. Analyses were conducted using statistical software (Stata version 11.0; StataCorp LP, College Station, Texas). Both models adjusted for the clustered, stratified survey design, and sample weights were applied to generate national population proportional estimates.
Table 1 includes the sociodemographic characteristics of the sample, the percentages in each illness group, and the overall frequency of each outcome. Three percent of the sample reported a nonasthmatic chronic illness (cancer, 116 [0.9%]; diabetes mellitus, 120 [0.9%]; and epilepsy, 163 [1.2%]), 2111 (16.0%) reported having asthma, and 10 726 (81.0%) reported none of these illnesses. The mean (SD) age of the sample was 22.0 (0.16) years and was the same across groups. Based on χ2 tests, all sociodemographic characteristics were significantly associated with illness category (results not shown).
Table 2 displays bivariate associations between illness groups and young adult outcomes, with significance testing across all 3 groups shown. All outcomes, except living with a parent/guardian, were associated with illness category. Young adults with nonasthmatic chronic illness had the lowest rates of high school graduation, ever having had employment, and currently having employment and the highest rates of receiving financial support from SNAP and SSI or disability insurance. The asthma group, compared with the healthy group, had slightly lower rates of currently having employment and living with a parent/guardian and slightly higher rates of ever having had employment and receiving support from SNAP and SSI or disability insurance (Table 2).
In Table 3, we provide 2 models. The first model compares the asthma group and the nonasthmatic chronic illness group with the healthy group. The second model compares the asthma group with the nonasthmatic chronic illness group. The lower part of Table 3 displays associations between control variables and young adult outcomes as estimated in model 1. For model 1 there were significant differences between young adults with nonasthmatic chronic illness and their healthy peers for all outcomes except living with a parent/guardian. Young adults with nonasthmatic chronic illness were less likely to graduate from high school, to ever have had employment, and to currently have employment and more likely to receive SNAP support and SSI/disability insurance (Table 3). There were no differences on any of the young adult outcomes between those individuals with asthma and their healthy peers except that those with asthma were less likely to live with their parent/guardian.
Model 2 shows that the nonasthmatic chronic illness group was significantly different from the asthma group on all outcome variables. The nonasthmatic chronic illness group was less likely to have graduated high school, to ever have had employment, and to currently have employment and more likely to receive support from SNAP, to receive SSI/disability insurance, and to live with a parent/guardian (Table 3).
At the time of interview, most young adults with the childhood chronic illnesses assessed in this sample (cancer, diabetes mellitus, and epilepsy) had completed their high school education, had current employment, and did not receive financial assistance from programs such as SSI or SNAP. However, compared with their healthy peers, this group of young adults had poorer educational, vocational, and financial outcomes. These findings are consistent with other research and confirm in a nationally representative US sample the negative association between childhood chronic illness and important young adult outcomes. For example, the consequences of young adults with chronic illness not graduating high school has real-world significance because adults without a high school diploma earn approximately $7000 less per year than do those with a high school diploma.20
Asthma is the most prevalent chronic illness of childhood, and young adults with moderate to severe asthma frequently have unmet health needs and require ongoing medical care.21,22 However, studies that include asthma or seasonal allergies in the chronic illness group without considering severity may be underestimating the effect of chronic illness on young adult outcomes. Studies based on samples with large proportions of young adults with asthma or allergies that do not take severity into account show less effect of chronic illness on educational outcomes compared with studies that exclude those with mild severity.9 Conversely, a Finnish case-control study that included only moderate to severe asthma in the chronic illness group showed lower educational attainment and employment.7 The present findings from the analysis of US young adults with chronic illness are consistent in demonstrating the need to distinguish asthma severity levels. In studies with fewer participants, smaller differences that occur when asthma severity groups are combined might not be detected; hence, including asthma without considering severity may lead to an optimistic bias regarding the young adult outcomes of those growing up with childhood chronic illness.
The noncategorical model for examining chronic illness is a valuable way of examining the outcomes of childhood chronic illness because there is a plausible common pathway between having significant childhood chronic illness and impaired young adult outcomes.1,15 There are multiple mechanisms by which children with chronic illness might struggle to become successful young adults, including educational problems related to missing school, psychological distress related to health problems, and family stress related to parental/guardian anxiety regarding a child's health or finances.2,23- 25 The exact mechanisms are not yet known and may differ based on generic and disease-specific characteristics. The present findings suggest that it is important to consider illness severity when categorizing individuals as having childhood chronic illness and examining adult outcomes of illness.
These findings are particularly relevant to pediatricians taking care of children with chronic illness who are interested in supporting such patients in a successful transition to adulthood and adult medical care. The 2002 American Academy of Pediatrics policy statement on health care transitions acknowledges the role of physicians in facilitating such transitions and notes the importance of a close relationship between physician and patient.26 To promote the broader success of children growing up with chronic medical conditions, pediatricians must recognize that these children are at increased risk for poor educational, vocational, and financial outcomes as young adults.
The present analysis has several limitations. First, owing to data limitations, only 3 chronic illnesses could be included in the nonasthmatic chronic illness group. It is likely that there are more children with significant chronic illness than the 3.0% identified by the present study. If other chronic illnesses have similar implications for adult outcomes, the differences documented herein between the healthy and chronic illness groups may be underestimates. Second, the present study did not take into account other details regarding the timing, severity, and treatment of the conditions examined, which are all factors that may affect young adult outcomes. Finally, there may be mediators of young adult outcomes that are specific to those growing up with diabetes mellitus, cancer, and epilepsy and that have distinctive implications. For example, those conditions could potentially affect cognitive processes; cognitive impairment would negatively affect the young adult outcomes examined herein. This type of cognitive effect contrasts with the more generic effects of growing up with a chronic illness, such as increased family stress, financial distress, missed school, and altered peer relations, which could affect young adult outcomes.27 Identification of the salient mediators is needed to develop targeted interventions that support young adults with chronic illness as they enter adulthood.
Future study is needed to examine noncategorical and disease-specific factors that affect the young adult outcomes of those growing up with childhood chronic illness. Specific mediators, such as school absenteeism, cognitive impairment, parent/guardian financial stress, and psychiatric illness, warrant investigation. In addition, longitudinal studies are needed to examine the trajectories that children with chronic illness follow as they move from childhood/adolescence to adulthood. The mean age of young adults in this study was 22 years; further study of adult outcomes, such as college graduation, marriage, and other long-term psychosocial and financial outcomes, is needed.
In conclusion, most young adults with chronic illness graduate high school, are employed, and do not receive governmental financial assistance. However, the results of this study confirm the increased risk of poor educational, vocational, and financial outcomes in young adults with chronic illness. Continued efforts are needed to support children growing up with chronic illness to become successful adults, particularly interventions that target educational attainment and vocational readiness. Pediatricians can play a role in promoting successful young adult outcomes by recognizing that such patients are at increased risk for educational, vocational, and financial problems.
Correspondence: Gary R. Maslow, MD, Cecil G. Sheps Center for Health Services Research, The University of North Carolina at Chapel Hill, 725 Martin Luther King Jr Blvd, Campus Box 7590, Chapel Hill, NC 27599 (firstname.lastname@example.org).
Accepted for Publication: August 18, 2010.
Author Contributions: All authors had full access to all the data in the study and take responsibility for the integrity of the data and the accuracy of the data analysis. Study concept and design: Maslow, Haydon, and Ford. Acquisition of data: Halpern. Analysis and interpretation of data: Maslow, Haydon, Ford, and Halpern. Drafting of the manuscript: Maslow and Haydon. Critical revision of the manuscript for important intellectual content: Maslow, Ford, and Halpern. Statistical analysis: Maslow, Haydon, and Halpern. Study supervision: Ford and Halpern.
Financial Disclosure: None reported.
Funding/Support: This research uses data from the National Longitudinal Study of Adolescent Health (Add Health), a program designed by J. Richard Udry, PhD, Peter S. Bearman, PhD, and Kathleen Mullan Harris, PhD, and funded by grant P01-HD31921 from the Eunice Kennedy Shriver National Institute of Child Health and Human Development, with cooperative funding from 23 other federal agencies and foundations. No direct support was received from grant P01-HD31921 for this analysis. Training support was provided by T32HP14001 from the Health Resources and Services Administration for the University of North Carolina National Research Service Award Primary Care Research Fellowship (Dr Maslow).
Additional Information: Persons interested in obtaining data files from Add Health should contact Add Health, Carolina Population Center, 123 W Franklin St, Chapel Hill, NC 27516-2524 (email@example.com).
Additional Contributions: Special acknowledgment is due to Ronald R. Rindfuss, PhD, and Barbara Entwisle, PhD, for assistance in the original design of Add Health. Annie-Laurie McRee, MPH, provided thoughtful critiques and comments on the manuscript, and the National Research Service Award Primary Care Research fellows read and commented on multiple drafts throughout the development of this article.
Maslow GR, Haydon AA, Ford CA, Halpern CT. Young Adult Outcomes of Children Growing Up With Chronic IllnessAn Analysis of the National Longitudinal Study of Adolescent Health. Arch Pediatr Adolesc Med. 2011;165(3):256-261. doi:10.1001/archpediatrics.2010.287