Bisphosphonate Aggravates Secondary Hyperparathyroidism in Hemodialysis Patients

Bisphosphonate可加劇尿毒症患者次發性副甲狀腺功能之亢進

曾金鳳(Chin-Feng Tseng) ； 盧國城(Kuo-Cheng Lu) ； 王進賢(Jinn-Shyan Wang) ； 朱益民(Ji-Min Chu) ； 楊麗琼(Lai-King Yeung)

《輔仁醫學期刊》 2卷4期 (2004/12) Pp. 301-310

摘要

Background and Purpose: Bisphosphonates have been reported to be effective in the treatment of patients with osteoporosis. Since patients on bisphosphonate may develop hypocalcemia, it is very likely that such therapy may aggravate secondary hyperparathyroidism in dialysis patients with osteopenia. This study investigated the short-term effects of bisphosphonate infusion on plasma calcium, serum parathyroid hormone (PTH) levels, and the calcium set point of the parathyroid gland in hemodialysis patients with secondary hyperparathyroidism. Methods: Fifteen patients with osteopenia on regular hemodialysis and with serum intact-PTH (PTH) levels of more than 200 pg/ml were included in this study. A second-generation bisphosphonate (pamidronate, Aredia(superscript ®) was administered intravenously as a single 15-mg dose in 150 ml of a 5% glucose solution for 1 h during the last hour of hemodialysis. The PTH responses to hypo- and hypercalcemia (induced with 1 and 4 meq/L of dialysate calcium, respectively) were evaluated before and 1 week after bisphosphonate administration. Results: Bisphosphonate infusion resulted in a reduction of predialysis plasma ionized calcium (iCa) of from 1.12±0.03 to 1.08±0.05 mmol/L (p＜0.05), and an increase in the baseline PTH of from 362.3±179.4 to 630.1±263.7 pg/ml (p＜0.001). The calcium set point for PTH showed an increasing trend after administration of bisphosphonate (1.12±0.03 vs. 1.15±0.04 mmol/L, p＜0.05). The slope of the PTH calcium curve was slightly but significantly increased (-1872.6±426.1 vs. -2086.3±571.1, p＜0.05) after bisphosphonate administration. Conclusion: Regulation of PTH secretion by calcium is altered after bisphosphonate administration in hemodialysis patients with secondary hyperparathyroidism. The reduction in plasma iCa not only induced a significant increase in PTH secretion but also increased the sensitivity of the parathyroid glands to calcium, which suggests that secondary hyperparathyroidism might worsen after administration of bisphosphonate.

關鍵字

Bisphosphonate ； 尿毒症 ； 鈣臨界點 ； 次發性副甲狀腺功能亢進

並列摘要

Background and Purpose: Bisphosphonates have been reported to be effective in the treatment of patients with osteoporosis. Since patients on bisphosphonate may develop hypocalcemia, it is very likely that such therapy may aggravate secondary hyperparathyroidism in dialysis patients with osteopenia. This study investigated the short-term effects of bisphosphonate infusion on plasma calcium, serum parathyroid hormone (PTH) levels, and the calcium set point of the parathyroid gland in hemodialysis patients with secondary hyperparathyroidism. Methods: Fifteen patients with osteopenia on regular hemodialysis and with serum intact-PTH (PTH) levels of more than 200 pg/ml were included in this study. A second-generation bisphosphonate (pamidronate, Aredia(superscript ®) was administered intravenously as a single 15-mg dose in 150 ml of a 5% glucose solution for 1 h during the last hour of hemodialysis. The PTH responses to hypo- and hypercalcemia (induced with 1 and 4 meq/L of dialysate calcium, respectively) were evaluated before and 1 week after bisphosphonate administration. Results: Bisphosphonate infusion resulted in a reduction of predialysis plasma ionized calcium (iCa) of from 1.12±0.03 to 1.08±0.05 mmol/L (p＜0.05), and an increase in the baseline PTH of from 362.3±179.4 to 630.1±263.7 pg/ml (p＜0.001). The calcium set point for PTH showed an increasing trend after administration of bisphosphonate (1.12±0.03 vs. 1.15±0.04 mmol/L, p＜0.05). The slope of the PTH calcium curve was slightly but significantly increased (-1872.6±426.1 vs. -2086.3±571.1, p＜0.05) after bisphosphonate administration. Conclusion: Regulation of PTH secretion by calcium is altered after bisphosphonate administration in hemodialysis patients with secondary hyperparathyroidism. The reduction in plasma iCa not only induced a significant increase in PTH secretion but also increased the sensitivity of the parathyroid glands to calcium, which suggests that secondary hyperparathyroidism might worsen after administration of bisphosphonate.

並列關鍵字

Bisphosphonate ； uremia ； calcium set point ； secondary hyperparathyroidism