Mental Health Treatment in Adults with Congenital Heart Disease in Germany: An Online, Cross-Sectional Study of Status, Needs, and Treatment Reasons.

Improved medical treatments have extended survival and life expectancy in adults with congenital heart defects (ACHD), placing greater emphasis on psychosocial health. Up to one-third of ACHD experience anxiety or depression, and half develop a mental illness during their lifetime. While there is solid evidence on the prevalence of mental health, many do not receive psychological, psychotherapeutic, or psychiatric treatment (PST) and the psychological care situation remains understudied. In a nationwide, online cross-sectional survey conducted in Q1 2024, 1486 ACHD aged 18 to 85 (M_age = 36.84 years; 60.8% female) registered in the German National Register for Congenital Heart Defects (NRCHD) completed self-report questionnaires on sociodemographics, illness identity (Illness Identity Questionnaire), mental well-being, and utilisation of PST. CHD diagnoses were determined in conformity with the International Pediatric and Congenital Cardiac Code (IPCCC) and CHD was classified according to Warnes et al. (simple/moderate/complex). Analyses included chi-square tests, t-tests, and binary logistic regression. Overall, 32.8% of participants reported current and/or previous PST (women 37.5%, men 25.3%). PST utilisation was significantly higher in those with complex (40.2%) compared to moderate (29.6%) and simple CHD (25.3%) (ps < 0.01). Primary treatment reasons were mental illness (41.7%) and CHD-related concerns (37.2%). Nearly half of treatments were self-initiated (45.8%) and about one-third were physician-recommended (30.8%). Logistic regression revealed CHD severity as a significant predictor of PST use (ps < 0.05), with lower odds for simple (OR = 0.48) and moderate (OR = 0.66) compared to complex CHD when controlling for sex (p < 0.001, OR = 1.87), age (p = 0.022, OR = 1.011), education level (ps between 0.060 and 0.780), and net income (ps < 0.05). Those receiving PST showed significantly higher maladaptive illness-identity scores (engulfment, rejection) and lower acceptance. Approximately one in three ACHD requires mental health support, particularly those with complex CHD. The CHD itself acts as a key stressor and treatment motivator. Findings underscore the need for integrated care linking cardiological and psychosocial services. Routine screening for psychological distress and low-threshold access to PST-also for patients with simple and moderate CHD-are essential to identify and address mental health needs early.