Abstract P72: The Obesity Paradox: Association Between Body Mass Index (BMI) and Disability After Stroke

Abstract

Background: Present rise in the incidence of obesity has led to several opposing reports regarding the association between obesity and stroke outcomes. The objective of this study was to investigate a proposed paradoxical relationship between body mass index (BMI) and functional status in ischemic stroke patients at time of hospital discharge. Methods: Saint Francis Hospital Comprehensive Stroke Center patient databases were utilized in identifying 948 patients eligible for retrospective chart review over a period of 15 months. Subjects were divided into 4 groups according to BMI: underweight (BMI < 18.5 kg/m 2 ), normal weight (BMI 18.5-24.9 kg/m 2 ), overweight (BMI 25.0-29.9 kg/m 2 ), and obese (BMI ≥ 30.0 kg/m 2 ). Covariates, such as age, gender, prior to event modified Rankin scale (mRS), stroke recurrence, and smoking, were considered. Functional status and disability of stroke patients was scored via mRS at hospital discharge. Ordered logistic regression, Pearson’s chi-squared test, and Pearson’s r correlation were used for analysis to assess the association of BMI and functional status in ischemic strokes. Results: Of 948 eligible subjects, 49.9% were female and mean (SD) age was 69.4 (14.5) years. According to BMI, 22 (2.3%) were underweight, 247 (26.1%) normal weight, 319 (33.7%) overweight, and 360 (37.9%) obese. After adjusting for covariates, ischemic stroke patients with an increased BMI (OR, 0.98; 95% CI, 0.96-0.99) were not associated with increased disability risk upon discharge. Obese (16.2%) and overweight (14.1%) patients discharged with a mRS of 0 (back to baseline) or 1 more frequently compared to normal weight (6.1%) and underweight (0.21%) patients ( P <0.001). Furthermore, an inverse association between BMI status and disability was significantly evident ( r = -0.17, P < 0.001). Conclusion: Obese and overweight stroke patients discharge with a lower risk of disability than normal weight and underweight patients, supporting the existence of the “obesity paradox” in stroke. An inverse association between obesity status and functional outcome was identified and remained significant regardless of covariates.