Changes in body mass index and late postoperative outcomes in elderly coronary artery bypass grafting patients: A follow-up study

Abstract

The purpose of this study was to describe the extent to which late postoperative health outcomes vary as a function of change in body mass index (BMI) in persons ≥ 65 years of age undergoing elective coronary artery bypass grafting (CABG). The mean age of the 90 persons in the original sample was 72.27 (±4.85) years. At follow-up (x - = 18.73, s = 2.56 months postsurgery), 90% (n = 79 alive, n = 2 deceased, proxy completed interview) were contacted; 73% (n = 59) completed the telephone interview; and 9% (n = 8) were alive but lost to follow-up. BMI (kg/m 2) was calculated from self-reported weight at follow-up. Outcomes included the Physical Component Summary (PCS) scale of the SF-36 Health Survey and readmission data. The x - (s) for BMI at preoperative, postoperative, postdischarge, and follow-up were 28.1 (4.9) kg/ m 2, 28.76 (4.9) kg/m 2, 27.11 (4.8) kg/m 2, and 27.95 (4.7) kg/m 2, respectively. BMI changed over time, P < 0.05. Those who were readmitted lost more weight between preoperative and postdischarge than those who were not readmitted (x - BMI = -2.26 vs. x - BMI = -1.35), t = 2.77, df = 27.05, P = 0.04. Those who lost less weight between preoperative and postdischarge were less likely to be readmitted, χ 2 = 5.755 (1), P = 0.02, with 25% sensitivity and 92% specificity. The x - (s x- for PCS at preoperative, postdischarge, and follow-up were 36.93 (1.62), 35.72 (1.27), and 42.26 (1.45), respectively, reflecting change over time, F = 11.43 (2), P < 0.007. At follow-up, older elective CABG patients do not appear to regain weight lost between preoperative and postdischarge; however, self-reported physical health is improved. Also, initial weight loss is related to readmissions. Copyright © 2004 Sage Publications.