Chen Y, Cao Y, Allen V, Richards JS. Weight matters: physical and psychosocial well being of persons with spinal cord injury in relation to body mass index. Objective To examine the relationship of body mass index (BMI) with multiple health indices among persons with spinal cord injury (SCI). Design Multicenter cross-sectional study. Setting A total of 16 SCI Model Systems throughout the United States. Participants A total of 1107 men and 274 women (N=1381), mean age ± SD, 43.1±14.6 years (tetraplegia, 56.9%; complete injuries, 50.2%; mean years since injury ± SD, 7.8±8.6), who received follow-up in 2006 to 2009, were classified into 1 of the 4 BMI categoriesunderweight, normal, overweight, and obesebased on self-reported height and measured weight. Interventions Not applicable. Main Outcome Measures Rehospitalization, pain, self-perceived health, FIM, Craig Handicap Assessment and Reporting Technique, Patient Health Questionnaire-9 (PHQ-9), and the Diener's Satisfaction With Life Scale (SWLS). Results The prevalence of underweight, overweight, and obesity was 7.5%, 31.4%, and 22.1%, respectively, which varied by age, sex, marital status, education, and neurologic impairment. For those with tetraplegia and functional motor-complete injuries, rehospitalization occurred more frequently among obese persons, while days rehospitalized were the longest among underweight persons. Pain was more severe in those classified as obese. Community mobility was lower in the underweight, overweight, and obese groups than in those with normal weight. There was no significant association between BMI and self-perceived health, FIM, PHQ-9, and SWLS beyond the effect of neurologic impairment. Conclusions Prevention and intervention directed at those significantly overweight or underweight deserve consideration as priorities in the continuity of care for persons with SCI. Efforts should be targeted particularly to those at higher risk, including persons with more severe injuries, who are less educated, and who are living alone. © 2011 American Congress of Rehabilitation Medicine.