The burden of prevalent fractures on health-related quality of life in postmenopausal women with osteoporosis: the IMOF study.

OBJECTIVE: Vertebral fractures are a common complication of osteoporosis and may have a negative effect on health-related quality of life (HRQOL). We investigated the effect of prevalent vertebral fractures on HRQOL in patients with osteoporosis.
METHODS: A cross-sectional multicenter study was carried out among postmenopausal women with primary osteoporosis attending primary care centers and hospital outpatient clinics: 234 women with vertebral fractures and 244 asymptomatic women. Women with secondary osteoporosis or taking medications that affect bone metabolism were excluded. All patients were questioned using the mini-Osteoporosis Quality of Life Questionnaire (mini-OQLQ), Medical Outcomes Study Short Form-36 (SF-36), and the EuroQuol-5D, after assessment of all clinical variables and anthropometric data. To assess comorbidity we used the Self-Administered Comorbidity Questionnaire (SCQ). Diagnosis of osteoporosis was confirmed in all patients by bone mineral density using dual energy x-ray absorptiometry. Radiographic evaluation was performed by a musculoskeletal radiologist. A total of 483 postmenopausal women, randomly matched for age out of 1579 healthy controls, were chosen to compare the SF-36 scores with respect to patients with and without vertebral fractures due to osteoporosis. A multivariable regression analysis was conducted to identify the strongest determinant for low HRQOL, adjusted for potential confounding variables such as comorbid conditions, education level, and psychosocial status.
RESULTS: The vertebral fracture group had significantly lower scores than patients without fractures and controls in all domains of the generic and specific questionnaires. Women with only 1 prevalent fracture had statistically significantly lower HRQOL scores than those without fractures on SF-36 measures of bodily pain, physical functioning, and role function physical (all p < 0.01). HRQOL scores were lower in women with lumbar fractures compared with women with thoracic fractures only when the physical functioning and bodily pain dimensions approached statistical significance. Based on the multivariate analysis, the strongest determinant for low HRQOL was physical functioning (explained by number of vertebral fractures) followed by comorbidity score and age. Adjusted R2 in the final model was 35.9%. Using the SF-36 summary scales, comorbid conditions predominantly affected either mental or physical health (p < 0.0001). A significant correlation (p <0.0001) was found between total score on the mini-OQLQ and the mean SCQ comorbidity score.
CONCLUSION: Our results confirm previous findings that HRQOL, assessed by generic and osteoporosis-specific instruments, is decreased in patients with vertebral fractures due to osteoporosis as a function of the number of vertebral fractures, presence of comorbid conditions, and age.