Comorbidities Among Young Adults with Congenital Heart Defects: Results from the Congenital Heart Survey To Recognize Outcomes, Needs, and well-beinG — Arizona, Arkansas, and Metropolitan Atlanta, 2016–2019

An estimated 1.4 million adults in the United States live with congenital heart defects (CHDs), yet their health outcomes are not well understood (1). Using self-reported, cross-sectional data from 1,482 respondents in the 2016-2019 Congenital Heart Survey To Recognize Outcomes, Needs, and well-beinG (CH STRONG) (2), CDC and academic partners estimated the prevalence of comorbidities among adults with CHDs aged 20-38 years born in Arizona (AZ), Arkansas (AR), and metropolitan Atlanta, Georgia (GA) compared with the general population (aged 20-38 years) from the National Health and Nutrition Examination Survey (NHANES) during 2015-2018 (3) and the AZ, AR, and GA Behavioral Risk Factor Surveillance Systems (BRFSS) during 2016-2018 (4). Adults with CHDs were more likely than those in the general population to report cardiovascular comorbidities, such as a history of congestive heart failure (4.3% versus 0.2%) and stroke (1.4% versus 0.3%), particularly those with severe CHDs (2). Adults with CHDs were more likely to report current depressive symptoms (15.1% versus 8.5%), but less likely to report previous diagnoses of depression (14.2% versus 22.6%), asthma (12.7% versus 16.9%), or rheumatologic disease (3.2% versus 8.0%). Prevalence of noncardiovascular comorbidities was similar between adults whose CHD was considered severe and those with nonsevere CHDs. Public health practitioners and clinicians can encourage young adults with CHDs to seek appropriate medical care to help them live as healthy a life as possible.

The CH STRONG sample was limited to persons aged 20-38 years (to match NHANES age groups for cardiovascular comorbidities) and to those without missing data for demographics or comorbidities. Furthermore, for the analyses of current depressive symptoms assessed using the PHQ-2, CH STRONG participants who did not self-report were excluded (to match the NHANES self-report data). To reduce nonresponse bias and generate population-based estimates, the CH STRONG participant population was standardized to the CH STRONG eligible population (9,312) by sex, birth cohort, maternal race/ethnicity, place of birth, and CHD severity. In addition, the general population samples (NHANES and BRFSS) aged 20-38 years were standardized to the CH STRONG eligible population by available demographic variables to reduce confounding. Standardized prevalence estimates were calculated for each cardiovascular and noncardiovascular comorbidity, as well as 95% confidence intervals (CIs) and p values for the difference in mean proportions between the standardized CH STRONG analytic sample and the standardized general population samples.
The CH STRONG sample was divided into two groups: those with severe CHDs and those with nonsevere CHDs (2). The unstandardized prevalence of cardiovascular and noncardiovascular comorbidities and the odds ratios between these two groups were measured and adjusted for sex, birth cohort, maternal race/ethnicity, and place of birth (adjusted odds ratios [aORs]). All analyses were conducted using SAS-callable SUDAAN (version 9.4; RTI International).
Among 9,312 eligible adults with CHDs, surveys were sent to 6,947 with available addresses; 1,656 surveys were returned (24% response rate). Of those, 1,626 were aged 20-38 years, 1,482 (91.1%) of whom included data on the variables of interest. Among these, 54% were female, 76% were non-Hispanic White, and the mean age was 26.1 (standard deviation = 4.6) years (Table 1). One third of the respondents had severe CHDs. A total of 1,174 eligible participants (79.2%) completed the survey via self-report, with the remainder by proxy.
Compared with the general population, adults with CHDs were more likely to report a history of congestive heart failure (4.3% versus 0.2%, p<0.001) and stroke (1.4% versus 0.3%, p<0.001), but there were no significant differences for hypertension or myocardial infarction ( Figure). Adults with severe CHDs were significantly more likely than the general population to have had at least one cardiac comorbidity (19.8% versus 9.0%, p<0.05), but those with nonsevere CHD (11.0%) were not. Persons with CHDs were more likely to report depressive symptoms at the time of the survey than those in the general population (15.1% versus 8.5%, p<0.001), but were less likely to have reported a prior diagnosis of depression (14.2% versus 22.6%, p<0.001). Adults with CHDs were also less likely than the general population to have asthma (12.7% versus 16.9%, p<0.001) or rheumatologic disease (3.2% versus 8.0%, p<0.001) (Figure).
Results differed by severity of CHDs for cancer, diabetes, and overweight/obesity when compared with the general population. Those with severe CHDs reported a lower prevalence of cancer (0.5% versus 2.5%, p<0.001) and overweight/ obesity (52.7% versus 57.8%, p = 0.048) compared with the general population, but no difference for diabetes. Those with nonsevere CHDs reported a higher prevalence of diabetes single ventricle lesions, endocardial cushion defects, tetralogy of Fallot, transposition of the great arteries, truncus arteriosus, coarctation of the aorta, and interrupted aortic arch. ¶ Compared with the general population, the total CH STRONG population was more likely to report history of congestive heart failure, stroke, and current depressive symptoms and were less likely to report history of asthma, depression diagnosis, or rheumatologic disease. Those with severe CHDs reported a lower prevalence of cancer and overweight/ obesity compared with the general population, and those with nonsevere CHDs reported a higher prevalence of diabetes compared with the general population.

FIGURE. Prevalence of cardiovascular* (A) and noncardiovascular † (B) comorbidities among adults aged 20-38 years with congenital heart defects § (CHDs) compared with the general population aged 20-38 years -United
(3.7% versus 2.0%, p = 0.03) compared with the general population, but no differences for cancer or overweight/obesity.
Overall, persons with severe CHDs had 2.4 times the odds of reporting one or more cardiac comorbidity. The prevalence of noncardiovascular comorbidities was similar in the two groups ( Table 2).

Discussion
Advancements in the medical and surgical treatment of CHDs have led to a growing population of adults living with these conditions (6). With this growth has come an increasing need to understand the medical needs of these persons, especially as they age. These CH STRONG findings indicate that adults with CHDs are more likely than are adults in the general population to experience significant cardiovascular comorbidities, such as congestive heart failure or stroke. Regarding noncardiovascular comorbidities, results varied when comparing adults with CHDs with the general population. Persons with severe CHDs were more likely to have cardiovascular comorbidities than were those with nonsevere Abbreviations: aOR = adjusted odd ratio, CI = confidence interval. * Common severe lesions included single ventricle lesions, endocardial cushion defects, tetralogy of Fallot, transposition of the great arteries, truncus arteriosus, coarctation of the aorta, and interrupted aortic arch. † Unstandardized CH STRONG estimates adjusted for sex, maternal race/ethnicity, birth cohort, and site. § Composite variable of adults with ≥1 cardiovascular comorbidities. ¶ Participants with a score of ≥3 on the two-item Patient Health Questionnaire-2, with proxy report removed. In CH STRONG, 1,174 self-report participants answered both questions. ** Overweight/obesity defined as body mass index ≥25 kg/m 2 based on self-reported height and weight. † † Arthritis, gout, lupus, or fibromyalgia.
CHDs; the odds of having noncardiovascular comorbidities was similar between the two groups. Similar to these findings, a recent study of a German nationwide registry of patients with CHDs found comorbidities to be common, with 57% of patients with CHDs aged <40 years having at least one comorbidity, including 22% with diseases of the circulatory system (7). Consistent with the increased odds of current depressive symptoms among CH STRONG participants, a recent international collaborative study noted that adults cared for at a CHDs center, especially those with cyanotic heart disease, were more likely than were those in the general population to report depressive symptoms (8). In contrast to the findings of CH STRONG, an analysis of U.S. commercial claims data during 2010-2016 among privately insured adults aged 18-40 years found higher rates of not only cardiovascular comorbidities but also noncardiovascular comorbidities among those with CHDs compared with a matched cohort without CHDs (9). In the same study, persons with severe CHDs had lower risks of cardiovascular comorbidities than did those with nonsevere CHDs, but higher risks of noncardiovascular comorbidities. The differences in findings between CH STRONG and the study of U.S. commercial claims data might be explained by methods used to identify CHD patients, inclusion of only those with recent medical encounters, differences in age distribution, timeframe for comorbidities, or varying definitions of CHD severity.

Summary
What is already known about this topic?
There are now more adults than children living in the United States with congenital heart defects (CHDs), but their long-term outcomes are unknown.
What is added by this report?
In the 2016-2019 Congenital Heart Survey To Recognize Outcomes, Needs, and well-beinG, young adults with CHDs were more likely than young adults in the general population to report significant cardiovascular comorbidities such as congestive heart failure or stroke. Prevalence of noncardiovascular comorbidities did not differ by congenital heart defect severity.
What are the implications for public health practice?
Public health practitioners and clinicians can encourage young adults with CHDs to seek appropriate medical care to help them live as healthy a life as possible.
The findings in this report are subject to at least four limitations. First, patient-reported outcomes can be limited by low health literacy or inaccurate recall. This limitation might affect the overall prevalence estimates among the CH STRONG and general populations; however, given that questions on the CH STRONG and general population surveys were identical, the comparisons between groups are expected to be valid. Second, if those with CHDs were more likely to suffer mortality from certain comorbidities (e.g., cancer) than the general population, the results might be subject to survivor bias. Third, the data from CH STRONG were from AZ, AR, and GA, whereas the available comparison group for cardiovascular comorbidities was from the national NHANES sample. These groups may not be directly comparable, despite attempts to standardize the NHANES data to the CH STRONG population by various demographics. Finally, these findings might be limited by the CH STRONG response rate of 24%. The standardization methods previously described were employed to minimize the effects of potential response bias.
Based on these CH STRONG findings, adults with CHD might be more likely to experience cardiovascular morbidity, particularly those with severe CHDs. CHD severity does not appear to be associated with the prevalence of certain noncardiovascular comorbidities. These findings can inform providers, policy makers, patients, and families of the expectations and needs of a growing population of adults with CHDs. Awareness and education efforts aimed at clinicians can help improve the care across the lifespan for this population. Public health practitioners and clinicians can encourage young adults with CHDs to seek appropriate medical care to help them live as healthy a life as possible.