Cardiopulmonary fitness is associated with cognitive performance in patients with coronary artery disease

Abstract

Objectives: To investigate the association between cardiopulmonary fitness and cognitive performance in subjects with coronary artery disease (CAD).

Design: Cross-sectional observational study.

Setting: Outpatient cardiac rehabilitation.

Participants: Eighty-one subjects with CAD.

Measurements: Cardiopulmonary fitness was assessed by measuring peak oxygen uptake (VO(2Peak) ) in a standardized exercise stress test. The fraction of the predicted age and sex norm for VO(2Peak) was computed for each patient. A battery of neuropsychological tests including the Stroop, Trail-Making Test Part B, Digit Symbol Coding, Revised Brief Visuospatial Memory Test, California Verbal Learning Test 2nd Edition, and Mini Mental State Examination (MMSE) was administered, from which composite Z-scores were computed for tasks involving executive function and memory.

Results: Executive function, memory, and MMSE scores were correlated with VO(2Peak) , but only performance in the executive domain was independently associated with VO(2Peak) in multiple linear regression. In a multiple linear regression model controlling for potential clinical confounders, VO(2Peak) (β=.666, P<.001) and covariates accounted for 36% of the variance in executive function scores.

Conclusion: Poorer VO(2Peak) is associated with poorer cognition, particularly executive function, in subjects with CAD independent of other cardiac risk factors. Cardiopulmonary fitness may be a protective factor for cognition in patients with CAD.