The association of Parkinson's disease with bone mineral density and fracture in older women.
Among community-dwelling older women, compared to those without Parkinson's disease (PD), women with PD have 7.3% lower BMD and an increased risk for hip fracture (HR = 2.6). Studies reporting an association of Parkinson's disease (PD) with low bone mineral density (BMD) and increased fracture risk often have been prone to selection bias, and have not accounted for potentially important explanatory variables, including recent weight loss. Further, little is known about the association between PD and non-hip fractures. Consequently, we investigated the independent association of PD with hip BMD and long-term fracture risk. Associations of self-reported PD with hip BMD and incident hip and non-spine, non-hip fracture were analyzed using linear regression and Cox proportional hazards, respectively. This prospective cohort study analyzed 8,105 older women with known PD status (n = 73 with PD) at four US clinical centers of the Study of Osteoporotic Fractures. Compared to women without PD, age-adjusted mean total hip BMD was 7.3% lower in women with PD. Women with PD had a 2.6-fold higher age-adjusted risk for incident hip fracture. Parkinson's disease was not significantly associated with non-spine, non-hip fractures. In age-adjusted models, women with PD had lower hip BMD and increased hip fracture risk, associations that were no longer significant after further weight and multivariate adjustment. Older women with PD should be considered for evaluation and treatment to reduce their fracture risk.