Inhibitors of hydroxymethylglutaryl-coenzyme A reductase and risk of fracture among older women

Background Inhibitors of hydroxymethylglutaryl-coenzyme A reductase (statin s) increase new bone formation in rodents and in human cells in vitro. Stat in use is associated with increased bone mineral density of the femoral nec k. We undertook a population-based case-control study at six health-mainten ance organisations in the USA to investigate further the relation between s tatin use and fracture risk among older women. Methods We investigated women aged 60 years or older. Exposure, outcome, an d confounder information was obtained from automated claims and pharmacy da ta from October, 1994, to September, 1997. Cases had an incident diagnosis of non-pathological fracture of the hip, humerus, distal tibia, wrist, or v ertebrae between October, 1996, and September, 1997. Controls had no fractu re during this period. We excluded women with records of dispensing of drug s to treat osteoporosis. Findings There were 928 cases and 2747 controls. Compared with women who ha d no record of statin dispensing during the previous 2 years, women with 13 or more statin dispensings during this period had a decreased risk of non- pathological fracture (odds ratio 0.48 [95% CI 0.27-0.83]) after adjustment for age, number of hospital admissions during the previous year, chronic d isease score, and use of non-statin lipid-lowering drugs. No association wa s found between fracture risk and fewer than 13 dispensings of statins or b etween fracture risk and use of non-statin lipid-lowering drugs. Interpretation Statins seem to be protective against nonpathological fractu re among older women. These findings are compatible with the hypothesis tha t statins increase bone mineral density in human beings and thereby decreas e the risk of osteoporotic fractures.