SCREENING FOR OSTEOPOROSIS RISK BY CLINIC AL FACTORS IN WOMEN FOLLOWING PHYSIOLOGICAL MENOPAUSE

BACKGROUND: Densitometric screening for osteoporosis in postmenopausal women has not been demonstrated cost-effective. We have tried to iden tify clinical factors for screening previous to densitometry avoiding unnecessary explorations. PATIENTS AND METHODS: Setting: outpatient cl inics of a menopausal unit in a 450-bed general hospital. Cross-sectio nal study, in two steps, of two groups of 140 and 284 women attending for physiological menopause. A clinical questionnaire, physical data a nd lumbar densitometry (Hologic QDR 1000 (R)) were obtained classifyin g the cases as <<normal>> or <<low bone mass>> (osteopenia or osteopor osis) according with the WHO criteria. In the first group a logistic r egression analysis was done to identify predictive factors for abnorma l densitometry, then validated in the second group. Sensitivity, speci ficity, predictive values (PV) and classification ability of clinical factors were analyzed. RESULTS: Four factors were independent predicto rs of abnormal densitometry: age > 51 (odds ratio [OR] = 6.64; 95% CI, 2.36-18.7); body weight < 70 kg (OR = 4.32; 95% CI, 1.71-10.09); year s of fertility < 32 (OR = 3.77; 95% CI, 1.36-10.04), and number of liv e births > 2 (OR = 3.47; 95% CI, 1.27-9.53), Presence of one factor of fers: sensitivity 91.9%; specificity 15%; positive PV 66.6%, and negat ive PV 50%, whereas the presence of two factors offers: sensitivity 62 .7%; specificity 70%; positive PV 79.9%, and negative PV 50.3%. Clinic al screening allows, when two factors are present, to avoid a 35.5% of densitometries and the false-negative cases represent 18%. CONCLUSION S: Detection of bone-risk clinical factors (abnormal densitometry) yie lds a screening, previous to densitometry, that avoids at least one th ird of explorations in women with physiological menopause, improving t he efficiency of the test.