Background: Adults with congenital heart disease (CHD) are at increased risk of stroke but high-quality population level data on stroke incidence in these patients are scant.
Methods and results: A retrospective whole-population Western Australian cohort of adult patients with CHD aged 18 to 64 years was created and followed from January 2000 to December 2017 using linked hospital data. Stroke incidence rates within the adult cohort with CHD were calculated and compared with the general population via direct standardization. A nested case-control design assessed predictors of ischemic and hemorrhagic stroke within the cohort. Among 7916 adults with CHD, 249 (3.1%) incident strokes occurred at a median age of 47 years; 186 (2.3%) ischemic, 33 (0.4%) hemorrhagic and 30 (0.4%) unspecified strokes. Ischemic and hemorrhagic stroke incidence was, respectively, 9 and 3 times higher in adults with CHD than the general population. Absolute risk was low with annual rates of 0.26% (ischemic) and 0.05% (hemorrhagic). Highest rates were observed in adults with shunt and left-sided lesions. Predictors of ischemic stroke in adults with CHD included recent cardiac surgery, left-sided valve repair/replacements, shunt lesions, and traditional risk factors (hypertension, infective endocarditis, peripheral vascular disease, and tobacco use). Mental health disorders and increasing Charlson's comorbidity scores were strongly associated with higher risk of ischemic and hemorrhagic stroke. The CHA2DS2VASc score was associated with ischemic stroke incidence.
Conclusions: This study provides the first population-based stroke incidence estimates for adults with CHD in Australia, showing elevated stroke risk across different CHD lesions. It highlights the potential clinical importance of managing comorbidities, especially mental health.
Keywords: congenital heart disease; epidemiology; incidence; risk factors; stroke.