Antihypertensive Medications, Loop Diuretics, and Risk of Hip Fracture in the Elderly: A Population-Based Cohort Study of 81,617 Italian Patients Newly Treated Between 2005 and 2009

Objective: Our objective was to assess the relationship between antihypertensive drugs, loop diuretics, and the risk of hospitalization for hip fracture (HF). Design: We conducted a population-based study in a cohort of 81,617 patients from Lombardy (Italy) aged 70–90 years who were newly treated with antihypertensive agents or loop diuretics between 2005 and 2009. Cases were the 2153 patients who experienced the outcome (hospitalization for HF before 31 December 2012). For each case, up to three controls were randomly selected from the cohort to be matched for sex, age at cohort entry, and date of initial prescription. The case–control and case-crossover designs and the logistic regression for matched sets were used to measure the strength of the association between current use of an antihypertensive drug (within 30 days before the HF hospitalization) and the risk of outcome. Results: Case–control and case-crossover odds ratios (ORs) for current use of loop diuretics were 1.67 (95 % confidence interval [CI] 1.28–2.18) and 1.49 (95 % CI 1.05–2.10), respectively. Among patients aged 81–90 years, case–control and case-crossover ORs were 1.52 (95 % CI 1.04–2.21) and 1.82 (95 % CI 1.10–3.00) for current use of loop diuretics and 1.86 (95 % CI 1.03–3.35) and 1.88 (95 % CI 1.01–3.48) for α-blockers. No other agent was associated with the outcome. Conclusions: Evidence that loop diuretics and α-blockers are associated with a higher risk of HF was consistent in the two observational approaches. Clinicians should carefully consider the risk of falls in their selection of drugs for hypertension and in the clinical use of loop diuretics.