A longitudinal study of total and regional bone mineral content and biochemical markers of bone resorption in patients with idiopathic hypercalciuria on thiazide treatment.

The effect of thiazides on total body bone mineral content and axial (trunk) and peripheral (arms) bone mass was evaluated. First, dual-energy X-ray absorptiometry was used to study bone mass in 24 patients with idiopathic hypercalciuria and in 22 healthy subjects. Next, the patients were randomized into a group of 14 patients treated with chlorthalidone (50 mg/day) and a group of 10 untreated patients who served as controls; in these two groups biochemical and bone mass studies were repeated 1 year later. Compared with healthy controls, patients with idiopathic hypercalciuria had less bone mass in total body (p < 0.02), arms (p < 0.001), and trunk (p < 0.05). After 1 year, the group of patients treated with thiazides manifested an increase of bone mass in total body (p < 0.0045), arms, and trunk (p < 0.0001) and a decrease in 24-hour calciuria, urinary calcium/creatinine ratio, and serum tartrate resistant acid phosphatase concentration; the untreated group of patients lost bone mass in all three sites. Under baseline conditions, the groups of treated and untreated patients exhibited a negative linear regression between total body bone mass and both urinary calcium/creatinine (r2 = 0.234; p < 0.001) and serum tartrate resistant acid phosphatase concentration (r2 = 0.399; p < 0.0001). Our results confirm the favorable effect of thiazides on bone mass and provide evidence of enhanced bone remodeling in idiopathic hypercalciuria.

RCT Entities:   Population Interventions Outcomes