Preventive therapy may not reduce CV effect on cognitive decline
Preventive therapy to reduce risk for CV events may not have as significant an effect as once thought on cognitive impairment over time, according to findings published in JAMA Network Open.
Alison Offer, PhD, of the clinical trial service unit and epidemiological studies unit, Nuffield Department of Population Health at the University of Oxford, U.K., and colleagues sought to determine the association of cognitive aging with the avoidance of vascular events in CV intervention trials.
“In numerous studies, higher levels of vascular risk factors in midlife and cardiovascular disease and diabetes are associated with future risk of dementia and cognitive disease,” Offer and colleagues wrote. “Conversely, one important way that interventions that reduce vascular risk factors may prevent dementia is by preventing cerebrovascular and other vascular events.”
Offer and colleagues identified data from 45,029 participants receiving cognitive assessments (mean age, 68 years; 81% men).
Among the 1,197 participants with incident stroke, the event was associated with 7.1 years of cognitive aging (95% CI, 5.7-8.5).
Incident transient ischemic attack, MI, HF and new-onset diabetes were associated with 1 to 2 years of cognitive aging.
In the HPS study, randomization to statin therapy meant 2% of survivors avoided nonfatal TIA and 2% avoided a nonfatal cardiac event, yielding an expected reduction in cognitive aging of 0.15 years (95% CI, 0.11-0.19), the researchers wrote.
HPS had 80% power to detect a 1-year difference in cognitive aging, Offer and colleagues reported.
“The expected cognitive benefits of the effects of preventive therapies on cardiovascular events during even the largest randomized clinical trials may have been too small to be detectable. ... Novel strategies to assess decline in cognitive function more precisely that are feasible for use in large-scale randomized clinical trials may allow direct evidence about these benefits to emerge,” Offer and colleagues wrote. – by Earl Holland Jr.
Disclosures: Offer reports receiving grants from the British Heart Foundation, Cancer Research UK, the Medical Research Council, Merck and Roche. Please see the study for all other authors’ relevant financial disclosures.