Change in behavioral functional capacity is associated with preexisting cognitive function rather than with cognitive decline in patients 1 year after cardiac surgery

Abstract

Objective: The objective was to examine whether preexisting cognitive function rather than cognitive decline associated with intraoperative procedures may predict change in behavioral functional capacity in patients 1 year after cardiac surgery.

Method: Forty-five patients completed a cognitive evaluation, including the Trail Making Test part B (TMT-B) for attention and psychomotor speed, the Memory with 10-s interference for working memory, the Digit Span test for short-term memory and the Instrumental Activities of Daily Living (IADLs) questionnaire for behavioral functional capacity, before surgery and 1 year after cardiac surgery.

Results: Sixteen patients (36%) exhibited cognitive decline after cardiac surgery. Preoperative scores on TMT-B significantly predicted change in behavioral functional capacity as measured by IADLs (beta = 0.371, P < .05), whereas the postoperative cognitive decline and intraoperative variables were unrelated to residualized change scores in IADLs (all Ps > .08).

Conclusions: Preexisting cognitive dysfunctions as assessed by TMT-B can be a marker of preoperative brain dysfunction, which, in turn, in addition to brain damage caused by cardiac surgery procedures, may further predispose patients to poor behavioral functional capacity and outcome 1 year after surgery. Impaired cognitive functions before surgery should be considered when evaluating the effects of cardiac surgery procedures on long-term behavioral functional status of patients.