Association between bile acid turnover and osteoporosis in postmenopausal women.

Objective: The intestinal absorption of vitamin D is linked to bile acid absorption. This link may be abnormal in patients with osteoporosis. The aim of this study was to investigate a possible relation between osteoporosis and bile acid turnover, measured as whole-body Se-75-HCAT retention (WBR), in postmenopausal women.

Patients And Methods: Whole-body counts were recorded using an uncollimated gamma camera 3 h and 7 days after oral administration of Se-75-homocholic acid taurine (Se-75-HCAT) in 16 women aged 58-85 years with dual-photon X-ray absorptiometry (DEXA)-proven osteoporosis. WBR was expressed as physical decay-corrected counts at 7 days as a percentage of the counts at 3 h.

Results: Seven patients had unexplained diarrhoea. Six patients (five with diarrhoea) had WBR less than 19%. There was a significant difference in DEXA t-score between women with and without diarrhoea (P<0.02). There was a significant negative correlation (R s=-0.58; P<0.02) between WBR and alcohol consumption rated on a three-point scale: <1, 2-7 and >7 U/week.

Conclusion: Our results indicate an association between osteoporosis and diarrhoea that may be the result of abnormal bile acid turnover. The role of alcohol requires further investigation.