The impact of body mass index on mortality and morbidity in patients undergoing isolated valve surgery

Abstract

Background: This study aims to investigate the impact of body mass index (BMI) on early mortality and morbidity in patients undergoing isolated valve surgery. Methods: Between January 2004 and December 2012, medical records of 196 patients (115 males, 81 females; mean age 62.0 years; range 28 to 81 years) who underwent isolated valve surgery in our clinic with prospective follow-up data were retrospectively analyzed. The patients were divided into three groups according to their BMI values. Group 1 consisted of patients with a BMI <25 kg/m(2), group 2 consisted of patients with a BMI of >= 25 kg/m(2) to <30 kg/m(2) and group 3 consisted of patients with a BMI of >= 30 kg/m(2). Obesity was defined as a BMI of >= 30 kg/m(2). Groups were compared in terms of morbidity parameters including bleeding, respiratory, renal, neurological and sternal complications and in-hospital mortality. Results: Increased BMI was associated with increased diabetes prevalence and use of bronchodilator. According to postoperative data, there was no significant difference in duration of extubation, postoperative renal functions, neurological complications such as stroke and transient ischemic attack, length of intensive care unit or hospital stay among three groups. Obese patients in group 3 had significantly higher rates of respiratory complications including re-intubation (p=0.011) and postoperative bronchodilator need (p=0.034), sternal dehiscence and sternal infections (p=0.023) and in-hospital mortality (p=0.021). The bleeding complications were significantly higher in group 1 (p=0.004). Conclusion: Our study results suggest that obesity results in increased 30-day mortality and several morbidity parameters such as respiratory and sternal complications in patients undergoing isolated valve surgery.