Abnormal bone and calcium metabolism in immobilized Parkinson's disease patients.

Abstract

To elucidate the influence of immobilization-induced hypercalcemia on bone metabolism in Parkinson's disease (PD), we measured serum biochemical indexes and bone mineral density (BMD) in the second metacarpals of 142 elderly PD patients and 99 age-matched healthy controls. Serum concentrations of 25-hydroxyvitamin D (25-OHD), 1,25-dihydroxyvitamin D (1,25-[OH](2)D), ionized calcium, intact parathyroid hormone (PTH), and intact bone Gla protein (BGP) were measured. Urinary deoxypyridinoline (D-Pyr) was also measured. Increased serum calcium levels (mean, 1.27 mmol/L) were observed in PD patients, and the levels correlated negatively with the Unified Parkinson's Disease Rating Scale III (UPDRS III), indicating the presence of immobilization-induced bone resorption with resultant hypercalcemia. Decreased serum concentrations of 1,25-[OH](2)D (mean, 88.7 pmol/L) and 25-OHD (mean, 29.7 nmol/L) were noted. Serum PTH was decreased (mean, 25.2 ng/L). Serum BGP was decreased while urinary D-Pyr concentration elevated. A negative correlation was observed between 1,25-[OH](2)D levels and serum calcium or UPDRS III (P < 0.0001). In disabled PD patients, immobilization-induced hypercalcemia may inhibit secretion of PTH, which in turn suppresses 1,25-[OH](2)D production. 25-OHD insufficiency may also contribute to decreased 1,25-[OH](2)D. These abnormalities may be corrected by the suppression of bone resorption with bisphoshonate, and supplementations of calcium and vitamin D should be avoided in these patients.

• Authors: Yoshihiro Sato, Yoshiaki Honda, Jun Iwamoto, Tomohiro Kanoko, Kei Satoh
• Journal: Movement disorders : official journal of the Movement Disorder Society (Mov Disord) Vol. 20 Issue 12 Pg. 1598-603 (Dec 2005) ISSN: 0885-3185 [Print] United States
• PMID: 16114020 (Publication Type: Comparative Study, Journal Article, Retracted Publication)

Chemical References

• Vitamin D
• 1,25-dihydroxyvitamin D
• 25-hydroxyvitamin D
• Calcium

Topics

• Aged
• Analysis of Variance
• Bone Density (physiology)
• Bone Diseases, Metabolic (blood, etiology)
• Calcium (metabolism)
• Case-Control Studies
• Female
• Humans
• Immobilization
• Linear Models
• Male
• Middle Aged
• Parkinson Disease (blood, complications)
• Retrospective Studies
• Vitamin D (analogs & derivatives, blood)