Children with congenital heart disease surviving to adulthood are more likely to develop dementia and to do so at a younger age than the general population, a large population-based study found.
Overall, the Danish congenital heart disease population was at 61% elevated risk of dementia compared with peers without congenital defects (95% CI 1.29-2.02), researchers led by Carina Bagge, BSc, of Aarhus University Hospital in Denmark, reported online in Circulation.
They were particularly likely to get early-onset dementia (HR 2.59 before age 65, 95% CI 1.76-3.81) but more likely to get dementia later on in life as well (HR 1.32, 95% CI 1.00-1.75).
Dementia rates were markedly higher for subgroups as well:
- Congenital heart disease (CHD) without extra-cardiac defects: HR 1.38, 95% CI 1.08-1.76
- Adults with mild-to-moderate defects: HR 1.50, 95% CI 1.14-1.97
- Adults with severe defects: HR 1.96, 95% CI 1.15-3.34
“Our findings extend the knowledge of long-term neurologic impairment and mental health functional morbidities in the CHD population,” they wrote. “While previous studies have reported elevated risks of adverse neurodevelopmental outcomes among CHD individuals, including increased occurrence of depression, autism, and epilepsy compared to the general population, our study examined an older adult population to determine the later-life consequences of this neurologic outcome.”
“While the underlying pathophysiologic mechanisms are not completely understood, the potential etiologic factors appear multifactorial and consistent with previous finding within the neurodevelopmental scientific literature,” the investigators said.
Their Danish registry-based study included all adults with congenital heart disease diagnosed from 1963 through 2012 and alive at 30 years of age (n=10,632). The most common conditions were a atrial septal defect (26%) and ventricular septal defect (22%).
Those survivors were matched 1:10 to non-congenital heart disease peers from the Danish Civil Registration System.
The results of the study didn’t change when excluding all individuals with diagnosed mild cognitive impairments and amnestic syndromes, nor did the reclassification of unspecified dementias as Alzheimer’s disease alter the findings, according to Bagge and colleagues.
However, there was the possibility of congenital heart disease misclassification and survival bias in the records they relied upon.
“The CHD population in our study represented adults who survived at least to age 30. These survivors, with an increased risk of dementia, reflect a healthier CHD cohort, and our analyses may underestimate the true association between CHD and dementia,” they also acknowledged.