WASHINGTON (FRONTLINE MEDICAL NEWS) – Adults with congenital heart disease are at fourfold greater risk of experiencing an ischemic stroke by age 60 than is the general population, Mette Glavind reported at the annual meeting of the American College of Cardiology.

She presented a population-based study that included all 14,710 Danish adults with congenital heart disease (ACHD) diagnosed in 1963-1994. Taking advantage of Denmark’s comprehensive system of linked national registries, she and her coinvestigators created a control group consisting of 144,735 age- and birth year–matched individuals from the general population.

During follow-up, a total of 2,868 Danes included in the study had an ischemic stroke. The cumulative incidence of ischemic stroke in the ACHD cohort was 0.8% by age 30 and 8.2% by age 60, compared with 0.09% and 2.9%, respectively, in controls, according to Ms. Glavind, a medical student at Aarhus (Denmark) University.

The median age at diagnosis of stroke was 52 years in the ACHD group and 69 years in controls. The risk of early ischemic stroke – defined as stroke at age 18-60 – was increased by 3.97-fold in the ACHD group, compared with controls. The risk of stroke after age 60 was increased by 1.68-fold.

Stroke was more likely to prove fatal in the ACHD group. Their 30-day stroke mortality rate was 10%, compared with 9.6% in controls. This corresponded to an adjusted 44% increased risk of stroke mortality, which was statistically significant.

The severity of congenital heart disease modified the stroke risk. Patients with mild or moderate ACHD had a 3.25-fold increased risk of early stroke, compared with controls, while those with severe or univentricular ACHD were at 5.97-fold greater risk.

For purposes of this study, mild ACHD was defined as a biventricular defect that was not repaired surgically or percutaneously. Moderate ACHD was considered to have biventricular pathophysiology with surgical or percutaneous intervention. The severe ACHD category was reserved for cases involving complex biventricular abnormalities.

By these definitions, 41% of patients had mild ACHD, 21% moderate, 22% severe, and 1% univentricular ACHD; the rest of the patients were unclassified.

This study was supported by Aarhus University and Cincinnati Children’s Hospital. Ms. Glavind reported having no financial conflicts.