A population-based study of the association between coronary artery bypass graft surgery (CABG) and cognitive decline: the Cache County study.
BACKGROUND
The relationship between coronary artery bypass graft (CABG) surgery and cognitive decline remains uncertain, in particular with regard to whether there is delayed cognitive decline associated with this procedure.


METHODS
This was a population-based cohort study involving participants in the Cache County Study of Memory Health and Aging. At baseline the study enrolled 5,092 persons age 65 and older and followed them up three years later and again four years after that. Individuals who reported having undergone CABG surgery at study baseline or had this surgery in between follow-up waves were compared to individuals who never reported having the surgery. The main outcome measure was the Modified Mini Mental State (3MS). Multilevel models were used to examine the relationship between CABG surgery and cognitive decline over time.


RESULTS
Study participants who had CABG surgery evidenced 0.95 points of greater decline relative to baseline on the 3MS at the first follow-up interview after CABG, and an average of 1.9 points of greater decline at the second follow-up interview, than those without CABG (t = -2.51, df = 2,316, p = 0.0121), after adjusting for several covariates, including number of vascular conditions. This decline was restricted to individuals who were more than five years past the procedure and was not evident in the early years after the surgery.


CONCLUSIONS
CABG surgery is associated with accelerated cognitive decline more than five years after the procedure in a long-lived population. This decline is small and its clinical significance is uncertain. We could not find an association between CABG and decline in the first five post-operative years.
Lyketsos
Constantine G
CG
Division of Geriatric Psychiatry and Neuropsychiatry, Department of Psychiatry and Behavioral Sciences, School of Medicine, The Johns Hopkins University, Baltimore, MD, USA.
Toone
Leslie
L
Tschanz
Joann
J
Corcoran
Christopher
C
Norton
Maria
M
Zandi
Peter
P
Munger
Ron
R
Breitner
John C S
JC
Welsh-Bohmer
Kathleen
K
D000368:Aged; D003072:Cognition Disorders / Q000209:etiology*; D001026:Coronary Artery Bypass / Q000009:adverse effects*; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D018579:Patient Selection; D011184:Postoperative Period; D011594:Psychometrics