Osteoporosis and the risk of symptomatic nephrolithiasis: a population-based 5-year follow-up study in Taiwan.

This study estimates the risk of symptomatic nephrolithiasis within 5 years of newly diagnosed osteoporosis in a Taiwan population. This cohort study consisted of patients with a diagnosis of osteoporosis between Jan. 2003 and Dec. 2005 (N = 1634). Four age- and gender- matched patients for every patient in the study cohort were selected using random sampling as the comparison cohort (N = 6536). All patients were tracked for 5 years from the date of cohort entry to identify whether they developed symptomatic nephrolithiasis. Cox proportional hazard regressions were performed to evaluate the 5-year nephrolithiasis-free survival rates. During the 5-year follow-up period, 60 osteoporosis patients (3.7%) and 165 non- osteoporosis patients (2.5%) developed symptomatic nephrolithiasis. The adjusted HR of symptomatic nephrolithiasis was 1.38 times greater risk for patients with osteoporosis than for the comparison cohort (95% confidence interval (CI) 1.03-1.86; P < .05). Osteoporosis is very likely to be an independent risk factor for subsequent diagnosis of symptomatic nephrolithiasis.