Risk of fractures associated with treatment for benign prostate hyperplasia in men

Treatment of benign prostate hyperplasia with α-blockers may affect blood pressure while treatment with 5-α-reductase inhibitors may affect conversion of testosterone potentially leading to osteoporosis. In our study, neither 5-α-reductase inhibitors nor α-blockers were associated with negative effects on fractures, α-blockers perhaps being associated with a limited decrease in fractures.

The objective is to study fracture risk associated with drugs for benign prostate hyperplasia. The hypotheses were that (1) α-blockers may elevate fracture risk by causing presyncope/falls and (2) 5-α-reductase inhibitors may elevate fracture risk by lowering dihydrotestosterone.

This is a nationwide case-control study using all 9,719 male fracture patients aged ≥60 years in the year 2000 as cases and drawing 29,156 age- and gender-matched controls. The main exposure was the use of the drugs mentioned above for benign prostate hyperplasia. Confounder control included social variables, contacts to hospitals and general practitioners, alcoholism and other variables.

For the 5-α-reductase inhibitors, no change in overall risk of fractures was seen. No change in risk of hip, spine and forearm fractures was present. For the α-blockers, a decrease in overall risk of fractures was seen, as well as a decrease in the risk of hip and spine fractures, but only at average doses >0.5 defined daily doses per day. No decrease was seen for forearm fractures. A decreasing risk of any fracture, hip fractures and spine fractures were seen with increasing dose of α-blockers, while no such association was seen for the forearm fractures.

Neither the 5-α-reductase inhibitors nor α-blockers were associated with negative effects on fracture risk. A small trend towards a decrease in fracture risk may be present for the α-blockers. However, more research is needed to confirm if this trend is real.