Coronary Artery Bypass Graft Surgery and Dementia Risk in the Cardiovascular Health Study.
Level 3 - non-randomized controlled study
Prospective cohort study
PubMed 28263191 · doi:10.1097/WAD.0000000000000191
What was done
Investigators analyzed data from 3,155 elderly adults free of dementia at baseline from the US population-based Cardiovascular Health Study (CHS). They evaluated the association between a history of coronary artery bypass graft surgery (CABG) and adjudicated incident all-cause dementia, Alzheimer disease (AD), vascular dementia (VaD), and mixed dementia, adjusting for potential confounders, and subsequently pooled these results with a prior prospective study.
What was found
In the CHS cohort, participants with a CABG history had an increased risk of incident all-cause dementia (hazard ratio [HR] = 1.93; 95% CI, 1.36-2.74) and mixed dementia (HR = 2.73; 95% CI, 1.55-4.80) compared to those without CABG history. Associations for AD (HR = 1.71; 95% CI, 0.98-2.98) and VaD (HR = 1.42; 95% CI, 0.56-3.65) had wide confidence intervals crossing 1.0. When pooled with a prior prospective cohort, the pooled HR was 1.96 (95% CI, 1.42-2.69) for all-cause dementia, 1.71 (95% CI, 1.04-2.79) for AD, and 2.20 (95% CI, 0.78-6.19) for VaD.
Why it matters
This study establishes a long-term epidemiological link between undergoing CABG and later dementia risk in older adults. It highlights a patient population that may warrant long-term cognitive surveillance, while emphasizing the need to distinguish surgical effects from underlying vascular pathology.
Limits
The observational design cannot establish causality or determine if the risk is driven by the surgery itself versus the severity of underlying coronary artery disease. Imprecision was present for specific dementia subtypes, as reflected in wide confidence intervals for AD and VaD in the primary cohort. Details on surgical technique or perioperative factors were not described in the abstract.
Cited by
- partial Undergoing coronary artery bypass surgery increases the risk of cognitive impairment and Alzheimer's disease.