Two clinical trials (n=13,458) and eight observational studies (number of participants unclear) were included.
Hip fracture (8 observational studies and 2 clinical trials).
The observational studies (9,946 statin users, 141,554 statin nonusers) showed a reduced risk of hip fracture for statin users (OR 0.43, 95% CI: 0.25, 0.75). Statistical heterogeneity was observed but was no longer present when one study (Women's Health Initiative study) was removed from the analysis. The removal of this study did not substantially affect the results of the meta-analysis.
The clinical trials (total number 13,458, number of statin users unstated) did not find a statistically significant reduction in risk (OR 0.87, 95% CI: 0.48, 1.58). Heterogeneity was not observed for these trials.
A similar contradiction in findings was observed for nonspine fracture. Based on six observational studies (2,893 statin users, 54,728 statin nonusers) the OR was 0.69 (95% CI: 0.55, 0.88); there was no evidence of statistical heterogeneity. Two clinical trials (total number 13,458, number of statin users unstated) gave an OR of 1.02 (95% CI: 0.83, 1.26). Again, heterogeneity was not observed for these trials.