Patient population and study design
Between April 2015 and December 2016, a cohort of patients aged 70 or
more undergoing elective cardiac surgery with cardiopulmonary bypass
were recruited at three university-affiliated hospital of three
different regions of Spain (Madrid, Asturias, and Canary Islands).
Using this cohort of patients, we analyzed the changes in the level of
frailty after cardiac surgery with respect to the preoperative ones.
The Institutional Research Ethics Committees at each of the
participating hospitals approved the implementation of this study, and
every patient provided signed informed consent.
Exclusion criteria were urgent or emergent surgery, off-pump operations,
and the absence of the necessary capacity to understand and collaborate
in the study. Patients with neurological or physical impairment that
could bias the results of the frailty assessment were also excluded.
Frailty was assessed at the time of the hospital admission before the
operation, and six months after surgery, using the same frailty
assessment tools.
Medical records were used to extract demographic, clinical and
surgically related variables.