EFFECT OF TAMOXIFEN ON BONE-FRACTURES IN OLDER NURSING-HOME RESIDENTS

OBJECTIVES: To evaluate the association between tamoxifen (TAM) treatm ent and rate of bone fractures in older, nursing home residents. PARTI CIPANTS: A total of 93,031 women, aged 65 years and older, whose data were part of the 1993 New York State MDS and for whom there was docume ntation of treatment with at least one medication. SETTING: New York S tate long-term care facilities. DESIGN: Cross-sectional study via seco ndary analysis of 1385 matched sets of residents. Each set included on e resident who was receiving TAM treatment and up to four residents wh o were not. MEASUREMENTS: Measurements included age, ethnicity, TAM tr eatment, hormone replacement therapy, vision impairment, any bone frac tures, and, specifically, hip fractures. RESULTS: During the 1.5-year period for which bone fractures are documented in the 1993 MDS, the fr acture rates were: 7.62% in women not treated with TAM, 3.20% in women receiving 10 mg TAM daily, and 6.73% in women receiving 20 mg TAM dai ly. The odds ratio (OR) for bone fractures among women receiving 20 mg TAM daily compared with nontreated women was 0.916 (95% confidence in terval (CI): 0.720-1.164; P = .472), and was 0.312 (95% CI: 0.112-0.86 5; P = .025) for those receiving 10 mg daily. The rates of hip fractur e were 4.98%, 2.40%, and 4.57% for controls and women receiving 10 mg and 20 mg TAM daily, respectively. Whereas the hip fracture rate for w omen receiving 20 mg daily was statistically similar to that of the co ntrols (OR = .963; 95% CI: 0.718-1.291; P = .800), the difference betw een the controls and those receiving 10 mg daily approached significan ce (OR: 0.313; 95% CI: 0.096-1.018; P = .054). CONCLUSION: Although st andard treatment of 20 mt; TAM daily offers no apparent protection aga inst bone fracture in older nursing home residents, a daily 10 mg dose seems to be protective.