Neurocognitive outcomes 3 years after coronary artery bypass graft surgery: a controlled study.
Level 3 - non-randomized controlled study
Prospective non-randomized controlled cohort study
PubMed 18036903 · doi:10.1016/j.athoracsur.2007.06.054
What was done
A prospective controlled cohort study compared changes in cognitive performance from baseline to 3 years among four groups: on-pump coronary artery bypass graft (CABG) surgery (n = 152), off-pump CABG surgery (n = 75), patients with diagnosed coronary artery disease (CAD) managed without surgery (n = 99), and control subjects without CAD risk factors (n = 69). Standardized neuropsychological testing evaluated attention, language, verbal and visual memory, visuospatial skills, executive function, and psychomotor/motor speed at baseline, 12 months, and 36 months.
What was found
The abstract provides directional findings without exact test scores, confidence intervals, or p-values. Relative to baseline performance, no group exhibited statistically significant decline at 36 months across any cognitive domain. Between 12 and 36 months, changes in cognitive performance did not significantly differ between the on-pump and off-pump CABG groups. A nonsignificant trend toward mild cognitive decline occurred across all CAD cohorts, but differences in rate of change across groups were not statistically significant.
Why it matters
These findings indicate that late post-CABG cognitive decline is unlikely to be caused specifically by cardiopulmonary bypass, pointing instead toward underlying vascular disease or shared cardiovascular risk factors.
Limits
Allocation across surgical and control groups was non-randomized, introducing potential selection bias and unmeasured confounding. The abstract reports no numerical values, effect sizes, variance estimates, or p-values, and does not provide details on attrition or loss to follow-up over the 3-year period.
Cited by
- context Undergoing coronary artery bypass surgery increases the risk of cognitive impairment and Alzheimer's disease.