Differential Signature of Obesity in the Relationship with Acute Kidney Injury and Mortality after Coronary Artery Bypass Grafting

• Published in: Journal of Korean medical science Vol. 33; no. 48; p. e312
• Main Authors: Moon, Hongran, Lee, Yeonhee, Kim, Sejoong, Kim, Dong Ki, Chin, Ho Jun, Joo, Kwon Wook, Kim, Yon Su, Na, Ki Young, Han, Seung Seok
• Format: Journal Article
• Language: English
• Published: Korea (South) The Korean Academy of Medical Sciences 26.11.2018; 대한의학회
• Subjects: Acute Kidney Injury - etiology; Acute Kidney Injury - mortality; Aged; Body Mass Index; Coronary Artery Bypass - adverse effects; Female; Humans; Kaplan-Meier Estimate; Male; Middle Aged; Multivariate Analysis; Obesity - complications; Odds Ratio; Original; Postoperative Complications; Proportional Hazards Models; Retrospective Studies; Risk Factors; Thinness - complications; 의학일반; Obesity; Acute Kidney Injury; Coronary Artery Bypass Grafting; Mortality; Underweight
• ISSN: 1011-8934; 1598-6357
• DOI: 10.3346/jkms.2018.33.e312

Obesity is related to several comorbidities and mortality, but its relationship with acute kidney injury (AKI) and long-term mortality remain undetermined in patients undergoing coronary artery bypass grafting. Data from 3,018 patients (age ≥ 18 years) who underwent coronary artery bypass graft surgery from two tertiary referral centers were retrospectively reviewed between 2004 and 2015. Obesity was defined using the body mass index, according to the World Health Organization's recommendation. The odds and hazard ratios in post-surgical, AKI, and all-cause mortality were calculated after adjustment for multiple covariates. Patients were followed for 90 ± 40.9 months (maximum: 13 years). Among the cohort, 37.4%, 2.4%, 21.1%, 35.1%, and 4.0% of patients were classified as normal weight, underweight, overweight-at-risk, obese I, and obese II, respectively. Post-surgical AKI developed in 799 patients (26.5%). Patients in the obese groups (overweight-at-risk to obese II) had a higher risk of AKI than did those in the normal-weight group. During the follow-up period, 787 patients (26.1%) died. Underweight patients had a higher risk of mortality than did normal-weight patients, whereas overweight-at-risk, obese I, and obese II patients showed better survival rates. After coronary artery bypass graft surgery, obese patients encountered a high risk of AKI, and underweight patients exhibited a low chance of survival. Awareness of both obese and underweight statuses should be raised in these patients.