Review: parathyroid hormone increases lumbar spine bone mineral density and decreases vertebral fractures in osteoporosis.

M a i n r e s u l t s 20 RCTs (2361 patients) met the selection criteria. Types of osteoporosis included postmenopausal osteoporosis (10 RCTs), idiopathic male osteoporosis (2 RCTs), and glucocorticoid-induced osteoporosis (1 RCT). 18 RCTs evaluated human PTH(l-34) administered subcutaneously. Dosages of PTH varied markedly among RCTs. Treatment duration ranged from 6 weeks to 3 years. Comparisons included PTH plus hormone replacement therapy vs hormone replacement therapy alone (5 RCTs), PTH vs placebo (3 RCTs), PTH vs PTH followed by salmon calcitonin (3 RCTs), nafarelin acetate vs nafarelin acetate plus PTH administered intranasally (2 RCTs), PTH plus estrogen vs estrogen (1 RCT), PTH plus alendronate sodium vs alendronate sodium (1 RCT), and PTH plus calcitriol vs calcium (1 RCT). PTH increased lumbar spine bone mineral density in all RCTs at several dosages, for any duration, in different types of osteoporosis, and in combination with multiple agents. PTH also increased femoral neck bone mineral density in 2 RCTs; however, no changes in femoral neck bone mineral density were attributable to PTH therapy in 5 RCTs. At the femoral trochanter, 2 RCTs each reported an increase or no change in bone mineral density with PTH therapy. 3 RCTs reported a detrimental effect of PTH on radius bone mineral density. 2 RCTs (including the largest and highestquality RCT) reported that PTH decreased the incidence of radiographically detected spinal fractures. 1 RCT (n = 220) that directly compared 3 doses of PTH (15, 30, and 50 μg/wk subcutaneously for 48 wk) reported that increase in lumbar bone mineral density was dose-related (range 0.6% to 8.1%), but there were no changes at the femoral neck with any PTH dosage.