REDUCED BONE-DENSITY OF THE HIP IN ELDERLY PATIENTS WITH PARKINSONS-DISEASE

Parkinson's disease (PD) is a major cause of falls and reduced mobilit y in elderly people. Fractures often occur as a result of these falls but there have been no studies of bone mineral density (BMD) in PD. We have prospectively studied 29 elderly women (mean age 77 years) and 2 6 elderly men (mean age 74 years) with PD over 2 years and compared th em with similar numbers of age- and sex-matched controls. Bone mineral density was measured by dual X-ray absorptiometry. Women were more li kely to sustain fractures (38% compared with 8% of men).Mean BMD of th e lumbar spine was similar in the 55 combined PD patients compared wit h combined controls. However, the total hip BMD was 10% lower (p = 0.0 14) and the neck of femur BMD 12% lower (p < 0.004) in the 51 PD patie nts compared with controls. The relatively lon er hip BMD in elderly P D men and women combined with their abnormal gait and tendency to fall backwards or to the side may explain their excess risk of hip fractur es, particularly in women. The neuromuscular deficit in PD may differe ntially reduce hip BMD relative to other sites and may thus be amenabl e to measures designed to improve mechanical loading in the lower limb s in the early stages of PD.