Utility of DXA Screening for Diagnosis of Osteoporosis in Men Aged 70 Years and Older

Presentation Number: SUN 313
Date of Presentation: April 2nd, 2017

Joanna Khatib*1, Jamila Benmoussa1 and Aidar R. Gosmanov2
1Albany Medical College, Albany, NY, 2albany VA hospital, NY

Abstract

Introduction: Dual Energy x-ray absorptiometry (DXA) is recommended for osteoporosis screening in men 70 years and above. However, little is known how effective DXA screening is in diagnosing osteoporosis in this population. The aim of our study was to determine the efficacy of DXA for the diagnosis of osteoporosis in men 70 years and older without known fracture risk factors.

Methods: We retrospectively identified men in general endocrinology clinic, who are 70 year and old, and have undergone DXA screening for osteoporosis from January to July 2016. We excluded any patient with prior osteoporosis, prior fragility fracture, on steroids therapy, with history of end stage kidney disease or hyperparathyroidism. Results were analyzed using Students’ T test.

 Results: We identified 52 men without known osteoporosis risk factors who had DXA performed on the same DXA machine. We identified 3 groups of the patients who were diagnosed with either normal bone mineral density (BMD)(N=13), osteopenia (N=27), or osteoporosis (N=12). There was no significant difference among these groups in age, vitamin D or calcium levels. However, body mass index was higher in the normal BMD group (33.7±5.6 kg/m2) compared with either osteopenia (26.8±3.99 kg/m2) group or osteoporosis group (26.1±6.1 kg/m2) (P<0.001). There was a significant difference in the T score of the femoral necks: in the normal BMD group it was 0.15±1.22 vs -1.77±0.42 in osteopenia patients (P<0.001) or vs. -2.83±0.34 in osteoporosis subjects (P<0.001).

Calculating FRAX score, we found that one patient out of the 13 patients with normal BMD and 13 patients out of the 27 patients with osteopenia had ≥3% probability of hip fracture during next 10 years. None of our patients had a major osteoporotic fracture risk >20.

Discussion: In our group of men without known osteoporosis risk factors, screening with DXA showed that 23% of the patients had an unknown diagnosis of osteoporosis. In addition further investigations using FRAX score demonstrated that an additional 27% of men would be at significant fracture risk. Therefore based on the results of this study 50% of men without prior knowledge of skeletal condition predisposing to fracture would qualify for diagnostic workup to determine etiology of low BMD and/or therapy to reduce future fracture risk.

 

Nothing to Disclose: JK, JB, ARG