J Korean Med Sci.  2018 Nov;33(48):e312. 10.3346/jkms.2018.33.e312.

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

• Moon H
• Lee Y
• Kim S
• Kim DK
• Chin HJ
• Joo KW
• Kim YS
• Na KY
• Han SS

• KMID: 2426665
• DOI: http://doi.org/10.3346/jkms.2018.33.e312

Abstract

BACKGROUND
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.
METHODS
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).
RESULTS
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.
CONCLUSION
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.

Keyword

Acute Kidney Injury; Coronary Artery Bypass Grafting; Obesity; Underweight; Mortality

MeSH Terms

Acute Kidney Injury*
Body Mass Index
Cohort Studies
Comorbidity
Coronary Artery Bypass*
Coronary Vessels*
Follow-Up Studies
Global Health
Humans
Mortality*
Obesity*
Retrospective Studies
Survival Rate
Tertiary Care Centers
Thinness
Transplants