Objective: To study the association of long-term statin use and the risk of low-energy hip fractures in middle-aged and elderly women.
Design: A register-based cohort study.
Setting: Finland.
Participants: Women aged 45-75 years initiating statin therapy between 1996 and 2001 with adherence to statins ≥ 80% during the subsequent five years (n = 40,254), a respective cohort initiating hypertension drugs (n = 41 610), and women randomly selected from the population (n = 62 585).
Main outcome measures: Incidence rate of and hazard ratio (HR) for low-energy hip fracture during the follow-up extending up to 7 years after the 5-year exposure period.
Results: Altogether 199 low-energy hip fractures occurred during the 135 330 person-years (py) of follow-up in the statin cohort, giving an incidence rate of 1.5 hip fractures per 1000 py. In the hypertension and the population cohorts, the rates were 2.0 per 1000 py (312 fractures per 157,090 py) and 1.0 per 1000 py (212 fractures per 216 329 py), respectively. Adjusting for a propensity score and individual variables strongly predicting the outcome, good adherence to statins for five years was associated with a 29% decreased risk (HR 0.71; 95% CI 0.58-0.86) of a low-energy hip fracture in comparison with adherent use of hypertension drugs. The association was of the same magnitude when comparing the statin users with the population cohort, the HR being 0.69 (0.55-0.87). When women with poor (<40%), moderate (40 to 80%), and good adherence (≥ 80%) to statins were compared to those with good adherence to hypertension drugs (≥ 80%) or to the population cohort, the protective effect associated with statin use attenuated with the decreasing level of adherence.
Conclusions: 5-year exposure to statins is associated with a reduced risk of low-energy hip fracture in women aged 50-80 years without prior hospitalizations for fractures.