Predictors of Health-Related Quality of Life in 500 Severely Obese Patients

Objective: To characterize health-related quality of life (HRQL) impairment in severely obese subjects, using several validated instruments. Methods: A cross-sectional analysis of 500 severely obese subjects was completed. Short-Form (SF)-12 [ Physical (PCS) and Mental (MCS) component summary scores], EuroQol (EQ)-5D [ Index and Visual Analog Scale (VAS)], and Impact of Weight on Quality of Life (IWQOL)-Lite were administered. Multivariable linear regression models were performed to identify independent predictors of HRQL. Results: Increasing BMI was associated with lower PCS (-1.33 points per 5 kg/m(2) heavier; P < 0.001), EQ-index (-0.02; P < 0.001), EQ-VAS (-1.71; P= 0.003), and IWQOL-Lite (-3.72; P = 0.002), but not MCS (P = 0.69). The strongest predictors (all P< 0.005) for impairment in each instrument were: fibromyalgia for PCS (-5.84 points), depression for MCS (-7.49 points), stroke for EQ-index (-0.17 points), less than fulltime employment for EQ-VAS (-7.06 points), and coronary disease for IWQOL-Lite (-10.86 points). Chronic pain, depression, and sleep apnea were associated with reduced HRQL using all instruments. Conclusion: The clinical impact of BMI on physical and general HRQL was small, and mental health scores were not associated with BMI. Chronic pain, depression, and sleep apnea were consistently associated with lower HRQL.