The influence of overweight/obesity on patient-perceived physical functioning and health-related quality of life after primary total hip arthroplasty

BACKGROUND: Overweight/obesity in patients after total hip arthroplasty (THA) is a growing problem and is associated with postoperative complications and a negative effect on functional outcome. The objective of this study is to determine to what extent overweight/obesity is associated with physical functioning and health-related quality of life 1 year after primary THA. METHODS: A retrospective analysis of prospectively collected data from 653 patients who had undergone a primary THA was conducted. Physical functioning, health-related quality of life, body mass index (BMI), comorbidity, and postoperative complications were assessed by means of a questionnaire and from medical records. To determine to what extent overweight/obesity is associated with physical functioning and health-related quality of life after THA, a structural equation model (SEM) analysis was conducted. RESULTS: The association of BMI corrected for age, gender, complications, and comorbidity with physical functioning is -0.63. This means that an increase in 1 kg/m(2) BMI leads to a reduction of 0.63 points in the physical functioning score as measured with the Western Ontario and McMaster Universities Osteoarthritis Index (100-point scale). The prevalence of complications or comorbidity leads to a reduction of, respectively, 5.63 and 7.25 (one or two comorbidities) and 14.50 points in the case of more than two comorbidities on the physical functioning score. The same pattern is observed for health-related quality of life. CONCLUSIONS: The influence of overweight/obesity on physical functioning and health-related quality of life is low. The impact of complications and comorbidity is considerable. Refusing a patient a THA solely on the basis of overweight or obesity does not seem justified