Congenital heart disease (CHD) is associated with an increased risk of dementia, especially early onset dementia, according to research published online ahead of print February 12 in Circulation. A particularly increased risk of dementia was observed among middle-aged adults with CHD and signs of early onset dementia, the authors noted.
“These results support the importance of understanding the risk of adverse long-term neurologic outcomes in the growing and aging population with CHD,” said Carina N. Bagge, a medical student at Aarhus University Hospital in Aarhus, Denmark, and colleagues.
Carina N. Bagge
Examining Dementia Risk in Patients With CHD
CHD occurs in six to 10 per 1,000 live births and represents the most common group of congenital defects. Dementia is the sixth most common cause of death in the United States. Although neurodevelopmental deficits among infants and children with CHD are well studied, research on long-term neurologic outcomes in adults with CHD is limited. Based on the increased incidence of neurodevelopmental impairments and associated risk factors for dementia among patients with CHD, Ms. Bagge and colleagues hypothesized that the risk of dementia is higher in adults with CHD than in the general population.
To test this hypothesis, the authors performed a nationwide, population-based cohort study in Denmark using linked medical registries that included data from all Danish hospitals. They identified all adults who received a diagnosis of CHD between 1963 and 1974 (before age 15) and between 1977 and 2012 (at any age). For each patient with CHD, 10 individuals from the general population were matched by sex and birth year, using the Civil Registration System. The authors defined CHD as an abnormally structured heart or greater intrathoracic vessels at birth, said Ms. Bagge. Participants were followed from January 1, 1981, age 30, or the date of their first CHD registration until hospital diagnosis of dementia, death, emigration, or December 31, 2012. To examine potential variation in dementia risk, the investigators categorized patients according to cyanotic potential.
The primary outcome was a first-time hospital diagnosis of all-cause dementia in the inpatient or outpatient clinic setting. Investigators categorized dementia diagnoses as Alzheimer’s disease, vascular dementia, or other dementias.
CHD Severity Correlated With Increased Risk of Dementia
The investigators identified 10,632 adults with CHD and 103,403 adults from the general population;46% were male in both cohorts. The cumulative incidence of dementia was 4% at age 80 in both cohorts. The overall hazard ratio (HR) of dementia was 1.6 among adults with CHD, compared with the general population. The HR of dementia was 1.4 among patients with CHD without extracardiac defects, 1.5 among patients with mild-to-moderate CHD, and 2.0 for patients with severe CHD, including univentricular hearts. Finally, the HR for early-onset dementia (ie, onset younger than age 65) was 2.6, and the HR for late-onset dementia was 1.3 among patients with CHD.
“These results cannot be directly applied to young adults diagnosed with CHD in the present eras. However, it is important to recognize healthcare needs and risk factors affecting the larger number of middle-aged and older adults currently living with CHD,” said Ms. Bagge and colleagues.
—Erica Tricarico
Suggested Reading
Bagge CN, Henderson VW, Laursen HB, et al. Risk of dementia in adults with congenital heart disease: population-based cohort study. Circulation. 2018 Feb 12 [Epub ahead of print].