Background Few investigations have been conducted to study health-related quality of life (HRQoL) and its determinants in subjects with hip osteoarthritis (OA) before hip replacement surgery. Overall, we know that obesity is an important modifiable factor contributing to the onset and progression of OA but its impact on HRQoL is largely unexplored in this population.
Objectives We investigated the relationship between body mass and HRQoL in subjects with symptomatic hip OA. We determined the impact of cardiovascular comorbidity and social deprivation on HRQoL, and whether they modify the relationship between body mass and HRQoL. We also examined the impact of body mass on the course of HRQoL.
Methods We used data from the first 3 years of follow-up from the Knee and Hip Osteoarthritis Long-term Assessment (KHOALA) study, performed from 2007 to 2009. HRQoL was assessed by the SF-36 and the Osteoarthritis Knee and Hip Quality of Life (OAKHQOL) questionnaires completed at baseline and during follow-up. Body mass index (BMI), presence of cardiovascular diseases assessed by the Groll score and socioeconomic status assessed by the EPICES score were collected at baseline. The associated factors at baseline and predictors of HRQoL over time were evaluated by multiple linear regression models (cross-sectional analyses) and models for repeated measures (longitudinal analyses), respectively.
Results For 222 hip OA subjects included, the mean (SD) BMI was 26.9 (4.4) kg/m2; 37 (17.1%) had at least one cardiovascular comorbidity and 41 (20.9%) were considered socially deprived. With the cross-sectional analyses, we found that impaired HRQoL was associated with increased BMI on physical and pain dimensions (β = -1.5, p=0.02 and β = -0.6, p=0.00025 respectively for role physical and pain dimensions of the SF-36) and deprived status on mental dimensions (β = -19.6, p<0.0031 and β = -9.5, p<0.0009 respectively for role emotional and mental health dimensions of the SF-36). The presence of cardiovascular comorbidities was not significantly associated with HRQoL. The relationship between BMI and HRQoL was not modified by deprivation or cardiovascular disease. With the longitudinal analyses, we found that BMI was not associated with the course of HRQoL.
Conclusions In a large sample of prevalent and primary-care subjects with hip OA, body mass is associated with physical and pain dimensions of the HRQoL, independent of other factors studied. The association is weak, is not modified by social deprivation or presence of cardiovascular comorbidities and did not affect HRQoL during a 3-year follow-up. Moreover, deprived status seems associated with mental dimensions of HRQoL in these subjects.
Guillemin F, Rat A-C (co-first), Roux CH, et al. The KHOALA cohort of knee and hip osteoarthritis in France. Joint Bone Spine. 2012;79(6):597-603.
Acknowledgements The authors thank Juliette Oudot and the Clinical Investigation Center (Clinical Epidemiology) for the coordination and monitoring, Adélie Baertschi for data management, all investigators who recruited and followed subjects and the members of the scientific committee (J Coste, Paris-Descartes; L Euller Ziegler and CH roux, Nice; P Fardellone, Amiens; B Fautrel, Paris-Université Pierre-et-Marie-Curie; B Mazières, Toulouse; A Saraux, Brest).
Disclosure of Interest : None declared