Background and purpose: Osteoporosis is a bone disease that reduces bone strength and increases the risk of fractures. Evidence suggest an association between nephrolithiasis and osteoporosis and decrease in bone density. The aim of this study was to compare bone densitometry in women with kidney stones and women with no history of stones.

Materials and methods: A cross-sectional study was conducted in patients referring to medical centers in Sari, Iran 2015-2016. One hundred and twenty eligible women were compared in the two groups of with and without kidney stones based on demographic characteristics, anthropometric, biochemical, and bone densitometry findings. The groups were compared by t-test for quantitative variables and Chi-square test for qualitative variables in SPSS V19.

Results: The mean of age of participants was 53.64±6.8 years and 77 (64.2%) were postmenopausal. There were 39 women with nephrolithiasis and 38 without kidney stones. Family history of kidney stones and urinary calcium excretion in women with kidney stones were significantly higher than that in those without kidney stones (P = 0.002, P = 0.000). The mean values for bone density in lumbar spine in women with and without kidney stones were 0.851±0.17 and 0.946±0.13 (P=0.001). These values in femoral neck and total hip were 0.815±0.13 and 0.748±0.10 (P=0.003) and 0.891±0.13 and 0.965±0.10 (P=0.001), respectively.

Conclusion: It seems that nephrolithiasis and higher urinary calcium excretion are associated with lower bone mass. Therefore, earlier investigations for osteoporosis are suggested in patients with kidney stones and higher urinary calcium excretion.