Beneficial effect of intermittent cyclical etidronate therapy in hemiplegic patients following an acute stroke

Significant decreases in bone mineral density (BMD) occur on the hemiplegic side in chronic stroke patients, which correlate with the degree of paraly sis and hypovitaminosis D. In this double-blind, randomized, and prospectiv e study of 98 patients with hemiplegia involving both an upper and lower ex tremity (55 males and 53 females; mean age, 71.4 +/- 0.6 years) after an ac ute stroke, 49 were given etidronate for 56 weeks and 49 received a placebo . The BMD was measured by computed X-ray densitometry (CXD) of the second m etacarpal bone bilaterally. Forty age-matched control subjects were followe d for 56 weeks. At baseline, both groups had 25-hydroxyvitamin D [25(OH)D] insufficiency, increased serum ionized calcium and pyridinoline cross-linke d carboxy-terminal telopeptide of type I collagen (ICTP), and low serum con centrations of parathyroid hormone (PTH) and 1,25-dihydroxyvitamin D [1,25( OH)(2)D], suggesting immobilization-induced hypercalcemia and inhibition of renal synthesis of 1,25(OH)(2)D. The BMD on the hemiplegic side decreased by 2.3% and 4.8% in the etidronate and placebo groups, respectively (p = 0. 0003). After treatment, the serum 1,25(OH)(2)D concentration increased by 6 2.2% in the etidronate group and decreased by 12.4% in the placebo group. T he etidronate group had significant decreases in the serum ionized calcium and ICTP and increases in PTH and bone Gla protein (BGP), whereas the place bo group had higher serum calcium and ICTP concentrations but stable PTH. T hese results suggest that etidronate can prevent decreases in the BMD in he miplegic stroke patients because it decreases the serum calcium through inh ibition of bone resorption and causes a subsequent increase in the serum 1, 25(OH)(2)D concentration.