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To examine young adult outcomes in a nationally representative US cohort of young adults who grew up with a chronic illness.
Secondary analysis of nationally representative data from Wave III (2001) of the National Longitudinal Study of Adolescent Health.
The analytic sample included 13,236 young adults 18–28 years old at Wave III.
Self-report of a chronic physical illness (asthma, cancer, diabetes or epilepsy) in adolescence. Respondents with (1) asthma or (2) non-asthma chronic illness (cancer, diabetes, or epilepsy) were compared to subjects without these conditions.
Self-report of high school graduation, ever having a job, having a current job, living with parents, and ever receiving public assistance.
Three percent of young adults had non-asthma chronic illness (cancer, diabetes, or epilepsy) and 16% had asthma. The majority of young adults with chronic illness graduated high school (81%) and were currently employed (60%). However, compared to healthy young adults, those with a non-asthma chronic illness were significantly less likely to graduate high school, ever have a job, or have a current job and were more likely to receive public assistance. When compared to young adults with asthma, young adults with non-asthma chronic illness again had significantly worse young adult outcomes on all measures.
Most young adults growing up with chronic illness graduate high school and are employed. 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. While less than one percent 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 US, despite the variation in estimates, it is generally accepted that up to 12% of children have special health care needs, including both physical and emotional problems.1, 2
With improved medical care over 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 (MCHB) 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 about the educational, vocational and financial outcomes of young adults who grew up with chronic illness, especially as investigated in longitudinal designs.
European studies, mostly cross sectional, have found that compared to healthy controls, young adults who grew up with various types of chronic illnesses have lower educational and vocational attainment.6–8 However, in a longitudinal study from Finland no differences were found in similar outcomes.9, 10 In the United States, prior research 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.11,12, 13
A major limitation of prior 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 non-categorical approach to childhood chronic illness, which is based on the assumption that the effects of chronic illness are similar across disease categories. The non-categorical 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 four young adult outcomes that may be associated with childhood chronic illness among 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 will have lower rates of high school graduation and employment, and will be 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) will have outcomes similar to those without chronic illness, as much of this group will likely have mild asthma.
We used data from Waves I and III of the National Longitudinal Study of Adolescent Health (Add Health) contractual dataset. Add Health is a nationally representative sample of US adolescents enrolled in grades seven through twelve in the 1994–1995 school year (Wave I). Over 90,000 adolescents in 132 schools participated in the Wave I in-school survey, with 20,745 respondents (ages 12–19) also completing subsequent in-depth home interviews in the 1994–1995 school year. Wave III follow-up interviews (n = 15,170) were conducted approximately seven years after Wave I, in 2001 with a 77% response rate. As previously reported, total bias related to attrition is quite low (<1%).17 More information about 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 are drawn from Wave I; the remainder of the measures are based on Wave III.
At Wave III respondents were asked whether they had ever been diagnosed with asthma, cancer, diabetes, or epilepsy; no other childhood chronic illnesses were asked about in the survey. Respondents who reported only having asthma were included in the “asthma” group; respondents who reported at least one of the other illnesses (regardless of whether they had asthma too) were included in the “non-asthma 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, non-asthma chronic illness, or “healthy (referent). A dichotomous variable was also created to compare the “healthy” group with subjects with any chronic illness including asthma.
Respondents were coded as a high school graduate (1) if the respondent reported having a high school diploma or Graduated Equivalency Diploma (GED), and not a high school graduate (0) if they had neither. We included two indicators of vocational status: ever having had a full or part-time job and having a current full or part-time job. Each was coded as a dichotomous variable (1=yes, 0=no).
Several dichotomous economic outcomes were examined: currently receiving support in the form of food stamps from SNAP (Supplemental Nutrition Assistance Program), and currently receiving disability insurance/workman’s comp/unemployment or Supplemental Security Income (SSI) (1=yes, 0=no). In addition, living situation was assessed based on a household roster by grouping respondents who currently lived with a parent or 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 level of education for either parent as reported by the 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 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 three groups, then between groups using the chi-square test. Multivariable poisson regression was used to calculate risk ratios (RRs) for dichotomous outcomes, controlling for sex, age, race/ethnicity, and parent education.19 The multivariate analyses were conducted in multiple steps. In Model 1 the non-asthma chronic illness and asthma groups were each compared separately to the healthy group. In Model 2 the non-asthma chronic illness group was compared to the asthma group. Analyses were conducted using Stata 11.0 statistical software (College Station, Tx). Both models adjusted for the clustered, stratified survey design and sample weights were applied to generate national population proportional estimates.
Table 1 includes sociodemographic characteristics of the sample, the percentages falling into each illness group and the overall frequency of each outcome. Three percent of the sample reported a non-asthma chronic illness [cancer 116 (0.9%), diabetes 120 (1.0%), epilepsy 163 (1.3%)], 2,111 (16%) reported having asthma, and 10,723 (81%) reported none of these illnesses. The mean age of the sample was 22.0 years (SD=0.16) and was the same across groups. Based on chi-square 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 three groups shown. All outcomes, except for living with parents, were associated with illness category. Young adults with non-asthma chronic illness had the lowest rates of high school graduation, ever having a job, and currently being employed, and the highest rates of receiving financial support from SNAP and SSI or disability insurance. The asthma group, compared to the healthy group, had slightly lower rates of currently being employed and living with parents, while having slightly higher rates of ever having had a job, and receiving support from SNAP and SSI or disability insurance (Table 2).
In Table 3 we present two models. The first model compares the asthma group and the non-asthma chronic illness groups to the healthy group. The second model compares the asthma to the non-asthma chronic illness group. The lower part of Table 3 shows associations between control variables and young adult outcomes as estimated in model 1. For model 1 there were significant differences between young adults with non-asthma chronic illness and their healthy peers for all outcomes except living with a parent. Young adults with non-asthma chronic illness were less likely to graduate from high school; less likely to have ever had a job; less likely to have a current job; more likely to receive SNAP support; and more likely to receive SSI/disability insurance (Table 3). There were no differences on any of the young adult outcomes between those with asthma and their healthy peers, except those with asthma were less likely to live with their parents.
Model 2 shows that the non-asthma chronic illness group was significantly different from the asthma group on all outcome variables. The non-asthma chronic illness group was less likely to have graduated high school; less likely to have ever had a job; less likely to have a current job; more likely to receive support from SNAP; more likely to receive SSI/disability insurance; and more likely to live with a parent (Table 3).
At the time of interview, the majority of young adults with the childhood chronic illnesses assessed in this sample (cancer, diabetes, or epilepsy) had completed their high school education, were currently employed and did not require financial assistance from programs such as SSI or SNAP. However, compared to 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, as adults without a high school diploma earn approximately $7,000 less per year than 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 of an effect of chronic illness on educational outcomes compared to 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 did show lower educational attainment and employment.7 Our 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 non-categorical model for examining chronic illness is a valuable way of examining the outcomes of childhood chronic illness, as 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, or family stress related to parental anxiety about 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 (AAP) 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 these children are at increased risk for poor educational, vocational and financial outcomes as young adults.
The present analysis has several limitations. First due to data limitations only three chronic illnesses could be included in the non-asthma chronic illness group. It is likely that there are more children with significant chronic illness than the 3% identified by the present study. If other chronic illnesses have similar implications for adult outcomes, then the differences documented here between the healthy and chronic illness groups may be underestimates. Second, the present study was not able to take into account other details regarding the timing, severity, or 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, cancer, and epilepsy, and have distinctive implications. For example, diabetes, cancer, and epilepsy all could potentially affect cognitive processes; cognitive impairment would negatively affect the young adult outcomes examined here. 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, that 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 both non-categorical 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 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 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.
The majority of young adults with chronic illness graduate high school, are employed, and do not receive governmental financial assistance. However this study confirms the increased risk for poor educational, vocational and financial outcomes among 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 of educational, vocational, and financial problems.
This research uses data from Add Health, a program project designed by J. Richard Udry, Peter S. Bearman, and Kathleen Mullan Harris, and funded by a 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. Special acknowledgment is due Ronald R. Rindfuss and Barbara Entwisle for assistance in the original design. Persons interested in obtaining data files from Add Health should contact Add Health, Carolina Population Center, 123 W. Franklin Street, Chapel Hill, NC 27516-2524 (addhealth/at/unc.edu). No direct support was received from grant P01-HD31921 for this analysis.
Thanks to Annie-Laurie McRee, MPH for her thoughtful critiques and comments. Thanks also to the NRSA Primary Care Research Fellowship and fellows for reading and commenting on multiple drafts throughout the development of this paper. Training support for Gary Maslow, MD provided by T32HP14001 from the Health Resources and Services Administration for UNC’s NRSA Primary Care Research Fellowship. This research was also supported by grant 5 R24 HD050924, Carolina Population Center, awarded to the Carolina Population Center at The University of North Carolina at Chapel Hill by the Eunice Kennedy Shriver National Institute of Child Health and Human Development.