The effect of obesity on acute kidney injury after cardiac surgery.
OBJECTIVE
Postoperative acute kidney injury is a frequent and serious consequence of cardiac surgery. We undertook to investigate the association of obesity and the risk of acute kidney injury development after cardiac surgery.


METHODS
A total of 432 patients who underwent cardiac surgery with cardiopulmonary bypass between October 2009 and August 2010 were included in the final retrospective analysis. Obesity was defined as body mass index 30 kg/m(2) or greater. Acute kidney injury was defined as a creatinine increase of 25% or more from baseline at 48 hours after surgery.


RESULTS
The overall incidence of acute kidney injury was 29.9% (n = 129). There was an increased incidence of postoperative renal impairment in the obese versus nonobese cohort; however, this was not statistically significant (39% vs 25.9%, P = .007). Multivariate logistic regression revealed that body mass index 30 kg/m(2) or greater was independently associated with the development of postoperative acute kidney injury (odds ratio [OR], 2.12; 95% confidence interval [CI], 1.27-3.54; P = .004), as were age (OR, 0.98; 95% CI, 0.96-1.0; P = .04) and cardiopulmonary bypass time (OR, 0.99; 95% CI, 0.98-1.0; P = .048).


CONCLUSIONS
Obesity with body mass index 30 kg/m(2) or greater is independently associated with an increased risk of acute kidney injury after cardiac surgery. Further understanding of the molecular basis of this association is critical to the design of preventative strategies.
["O'Sullivan|Katie E|KE|", 'Byrne|John S|JS|', 'Hudson|Amy|A|', 'Murphy|Anna Marie|AM|', 'Sadlier|Denise M|DM|', 'Hurley|John P|JP|']
D058186:Acute Kidney Injury D000368:Aged D015992:Body Mass Index D006348:Cardiac Surgical Procedures D002315:Cardiopulmonary Bypass D005260:Female D006801:Humans D015994:Incidence D008297:Male D008875:Middle Aged D009765:Obesity D012189:Retrospective Studies D012307:Risk Factors
obesity acute kidney injury cardiac surgery postoperative