2008 Annual Meeting Abstracts
Hemoglobin A1c as a Predictor for Coronary Artery Bypass Graft Surgery Complications
Krista E. Evans, MD1, Bruce J. Leavitt, MD2, Turner M. Osler3, Mitchell Norotsky, MD2.
1University of Vermont, Gilford, NH, USA, 2University of Vermont & Fletcher Allen Health Care, Burlington, VT, USA, 3University of Vermont, Burlington, VT, USA.
To determine if HbA1c can be used as a predictor for CABG surgery risk.
A review of CABG patients’ laboratory workup, hospital course, and outcomes.
Setting: Tertiary Care Academic Medical Center.
Study subjects were 375 patients who had CABG surgery in 2007.
Main Outcome Measures: We reviewed the in-patient records to discover any complication within 30 days of surgery and placed each into the following categories: arrhythmias; cardiogenic shock/CHF, stroke; wound issues; other infections; pleural effusion; renal; gastrointestinal; hemorrhage; mortality; and all others.
375 CABG surgeries were performed. The mean age was 66 years (S.D. +/- 11.20). 49.3% of our patients had valid HbA1c labs. The range was 4.1 to 14.9% (S.D. +/-1.72%). 127 (69%) of the patients HbA1c levels were at or below the American Diabetes Association’s goal of < 7.0%. The fasting blood sugar mean was 124 mg/dL (S.D. +/- 39.66 mg/dL).
We performed logistic models for all complication categories with age, HbA1c, and fasting blood glucose as independent variables. Significant predictors of having any complication include age and HbA1c . The odds increase 5% (p=0.004) for every year older and 39% (p=0.001) for every increase in HbA1c by one point. Also, the odds of a stroke increase 7% (p=0.046) with every year older a patient is at the time of surgery. Lastly, the odds of mortality increase 5% (p=0.030) with the variable age.
Every 1 point increase in HbA1c increases the odds of having a complication following cardiac surgery by 39%. HbA1c may be predictor of risk and comorbidities that influence CABG surgery outcomes, and improvements in long term glucose control could improve the risk.