The primary care osteoporosis risk of fracture screening (POROS) study: Design and baseline characteristics

Objective: POROS evaluates a 3-step fracture risk screening program in women 50-64 not previously diagnosed with osteoporosis. This report details the research design and baseline characteristics. Methods: Recruiting from 6 primary care sites, baseline characteristics, including fracture risk factors, were assessed via self-administered questionnaires (SAQs). Subjects with >= 1 risk factor were randomized to Intervention or Non-Intervention. Those without any risk factors were placed in the No Risk Factors group. Bone turnover was measured in the Intervention group via urine N-telopeptide (NTx) testing. Subjects with NTx>50 had central hip and spine Dual-energy X-ray Absorptiometry (dxa). All groups were followed for 24 months, completing SAQs on osteoporosis management and fractures. At baseline, comparisons were made on demographics, health status, and prevalence of fracture risk factors. Results: 2839 women were enrolled and included in baseline analyses (1464 Intervention, 372 Non-Intervention, and 1003 No Risk Factors). The mean age was 56.1 and 81.1% were postmenopausal. As expected by randomization, the Intervention and Non-Intervention groups had similar baseline characteristics. The most commonly reported fracture risk factors were body mass index <24 kg/m(2) and needing to use arms to stand from a chair. Subjects in the No Risk Factors group were more likely to be younger, heavier, Hispanic, in good health, a nonsmoker, and to drink less alcohol.