Incident coronary heart disease (CHD) is associated with accelerated cognitive decline, with greater impacts on verbal memory, global cognition, and temporal orientation, according to a longitudinal study published in the Journal of the American College of Cardiology.
Researchers from China obtained follow-up patient data from the English Longitudinal Study of Aging. People with no history of stroke or incident stroke were included in the study (n=7888; mean age, 62.1±10.2 years). Patient data from 2002 to 2003 were combined with patient data from 2016 to 2017. Cognitive assessments were performed twice in all patients, including once at baseline as well as ≥1 time during wave 2 (2004-2005) to wave 8 (2016-2017). The aim of the study was to determine whether there was an association between incident CHD (ie, myocardial infarction and/or angina) and cognitive decline before and/or after the event.
A total of 480 CHD events occurred in the cohort during a median follow-up of 12 years. According to a multivariable-adjusted analysis, there was an accelerated rate of global cognitive decline in patients with CHD vs patients without CHD (-0.018 SD/year; 95% CI, -0.029 to -0.007).
The investigators also observed faster declines in temporal orientation (-0.015 SD/year; 95% CI, -0.027 to -0.003), sematic fluency (-0.011 SD/year; 95% CI, -0.019 to -0.003), and verbal memory (-0.015 SD/year; 95% CI, -0.023 to -0.008) in patients with incident CHD. Declines occurred faster after a CHD diagnosis vs before the event, particularly for global cognitive function (-0.039 SD/year; 95% CI, -0.063 to -0.015), verbal memory (-0.028 SD/year; 95% CI, -0.043 to -0.013), and temporal orientation (-0.038 SD/year; 95% CI, -0.068 to -0.007).
Limitations of the study include the reliance on self-reported doctor-diagnosed incident CHD data as well as the lack of adjustment for CHD symptom severity, acute treatments, and medications.
Although the study did not discover the mechanism driving cognitive decline in patients with CHD, the researchers hypothesized that “CHD might directly contribute to cognitive decline by causing cerebral hypoxia and silent brain lesions.”
Xie W, Zheng F, Yan L, Zhong B. Cognitive decline before and after incident coronary events. J Am Coll Cardiol. 2019;73(24):3041-3050.