Context: Impairment of muscle function and strength in patients with primary hyperparathyroidism (PHPT) is rarely addressed although decreased muscle function may contribute to increased fracture risk in PHPT.
Objective: We aimed to assess changes in muscle strength, muscle function, postural balance, quality of life (QoL), and well-being during treatment with vitamin D or placebo before and after parathyroidectomy (PTX) in PHPT patients.
Design and setting: Randomized placebo controlled trial at a single center.
Patients: We included 46 PHPT patients, mean age 58 (range 2977) years and 35 (76%) were women.
Interventions: Daily treatment with 70 μg (2800 IU) cholecalciferol or placebo for 52 weeks. Treatment was administered 26 weeks prior to PTX and continued for 26 weeks after PTX.
Main outcome measures: Changes in QoL and measures of muscle strength and function.
Results: During 26 preoperative weeks of medical treatment, we did not measure any beneficial effects of supplementation with vitamin D compared with placebo regarding QoL, postural balance, muscle strength, or function. In the entire group of patients, we measured marked improvements in QoL, well-being (P<0.01), muscle strength in the knee flexion and extension (P<0.001), and muscle function tests (P<0.01) after surgical cure by PTX. Postural balance improved during standing with eyes closed (P<0.05), whereas patients had a decreased stability with eyes open (P<0.05).
Conclusions: Patients with PHPT and vitamin D insufficiency did not benefit from vitamin D supplementation concerning muscle strength, muscle function, postural balance, or quality of life. Independent of preoperative vitamin D levels, PTX improved these parameters.
17 May 2014 - 20 May 2014