Use of α-blockers and the risk of hip/femur fractures

Objective. To study the association between use of alpha-blockers and risk of hip/femur fractures. Design. Population-based case-control study. Setting. General Practice Research Database. Subjects. Cases were defined as men, aged 40 years and older with a first diagnosis for hip/femur fracture. Controls were matched 1 : 1 on gender, year of birth and general practitioner-practice. Results. In all, 4571 cases and an equal number of controls were identified. Current use of alpha-blockers (prazosin, doxazosin, indoramin, terazosin, alfuzosin and tamsulosin) was compared with non-use of alpha-blockers. Current use of alpha-blockers on the index date was associated with an increased risk of hip/femur fracture [adjusted odds ratio (OR) 1.9, 95% confidence interval (CI): 1.1-3.0] in the overall analysis. The effect was particularly strong for first prescriptions within a treatment episode (adjusted OR 5.1, 95% CI: 1.0-31.7) and during the first month of treatment (adjusted OR 4.1, 95% CI: 0.7-23.9). Stratification according to indication of use showed that current use of alpha-blockers was not associated with hip/femur fracture in men with a diagnosis of benign prostatic hyperplasia (adjusted OR 1.0, 95% CI: 0.4-2.5), but was associated in men who used alpha-blockers for cardiovascular disease (adjusted OR 2.8, 95% CI: 1.4-5.4). Conclusion. Current use of alpha-blockers was associated with an increased risk of hip/femur fracture and with the start of a new treatment episode. The effect seemed to be confined to patients who used alpha-blockers for cardiovascular disease. Caution with respect to first-dose effects related to the initiation of a new episode of alpha-blocker treatment is advised.