Parathyroid Hormone Replacement Therapy in Hypoparathyroidism: A Meta-Analysis

Abstract

This study investigated the effect of human parathyroid hormone replacement therapy on specific disease-related outcomes in patients with hypoparathyroidism. Medline, Cochrane, EMBASE, and Google Scholar databases were searched until January 13, 2015 for randomized trials using the following search terms: hypoparathyroidism, parathyroid hormone/PTH, and hormone replacement therapy. Five randomized controlled trials (n=245) that investigated effect of either PTH (1-34) (3 trials) or PTH (1-84) (2 trials) on serum calcium, phosphate, 1, 25-dihydroxyvitamin D, 25-dihydroxyvitamin D levels, and urine level of calcium were included in the meta-analysis. Both PTH (1-34) and PTH (1-84) therapies were not associated with change in serum calcium level compared with calcitriol/placebo. The level of 24-h urine calcium excretion had a significant decrease in PTH (1-34)-treated group compared placebo/calcitriol (control) group (p≤0.012). PTH (1-34) did not change serum phosphate (p=0.053). PTH (1-84) did not change level of 24-h urine calcium excretion compared with control (p≥0.214) but it did decrease the levels of serum phosphorous (p=0.000). Both PTH-replacement therapies were not associated with change in serum 1,25-dihydroxyvitamin D level compared with control (p≥0.606), but were associated with a significant decrease in serum 25-dihydroxyvitamin D levels (p≤0.04). In conclusion, although the number of randomized trial is limited, our meta-analysis suggests that PTH (1-34) replacement therapy may maintain the serum calcium levels in the normal range by reducing the levels of urine calcium excretion, and both replacement therapies may maintain 1,25-dihydroxyvitamin D serum levels by reducing serum level of 25-dihydroxyvitamin D.