Osteoporosis treatment prevents hip fracture similarly in both sexes: the FOCUS observational study

• Published in: Journal of bone and mineral research 2024-09, Vol.39 (10), p.1424-1433
• Main Authors: Keaveny, Tony M, Adams, Annette L, Orwoll, Eric S, Khosla, Sundeep, Siris, Ethel S, McClung, Michael R, Bouxsein, Mary L, Fatemi, Shireen, Lee, David C, Kopperdahl, David L
• Format: Article
• Language: English
• ISSN: 0884-0431; 1523-4681; 1523-4681
• DOI: 10.1093/jbmr/zjae090

Randomized trials have not been performed, and may never be, to determine if osteoporosis treatment prevents hip fracture in men. Addressing that evidence gap, we analyzed data from an observational study of new hip fractures in a large integrated healthcare system to compare the reduction in hip fractures associated with standard-of-care osteoporosis treatment in men versus women. Sampling from 271 389 patients age ≥ 65 who had a hip-containing computed tomography scan during care between 2005-2018, we selected all who subsequently had a first hip fracture (cases) after the CT scan (start of observation) and a sex-matched equal number of randomly selected patients. From those, we analyzed all who tested positive for osteoporosis (DXA-equivalent hip bone mineral density T-score ≤ -2.5, measured from the CT scan using VirtuOst). We defined "treated" as at least six months of any osteoporosis medication by prescription fill data during follow up; "not-treated" was no prescription fill. Sex-specific odds ratios of hip fracture for treated versus not-treated patients were calculated by logistic regression; adjustments included age, BMD T-score, a BMD-treatment interaction, body mass index, race/ethnicity, and seven baseline clinical risk factors. At two-year follow-up, 33.9% of the women (750/2211 patients) and 24.0% of the men (175/728 patients) were treated, primarily with alendronate; 51.3% and 66.3%, respectively, were not-treated; and 721 and 269, respectively, had a first hip fracture since the CT scan. Odds ratio of hip fracture for treated versus not-treated was 0.26 (95% confidence interval: 0.21-0.33) for women and 0.21 (0.13-0.34) for men; the ratio of these odds ratios (men:women) was 0.81 (0.47-1.37), indicating no significant sex effect. Various sensitivity and stratified analyses confirmed these trends, including results at five-year follow-up. Given these results and considering the relevant literature, we conclude that osteoporosis treatment prevents hip fracture similarly in both sexes.