CT and DXA Bone Fragility Evaluation after Bariatric Surgery

Objectives: The objectives were to determine the prevalence of bone fragility 3 years (±6 months) after bariatric surgery via DXA and computed tomography (CT) in patients with obesity; to identify the risk factors for the bone fragility development (bone mineral density [BMD] ≤-2SD or a scanographic bone attenuation coefficient of the first lumbar vertebra (SBAC-L1) ≤145 Hounsfield units (HU)) and to compare the results obtained via CT and DXA. Methods: This descriptive study included patients with obesity who underwent bariatric surgery and DXA and CT before and 3 years (±6 months) after bariatric surgery. Results: Among the 44 included patients, 84.1% were women, with a mean age of 53.9 years (±10.7). After 3 years, there was a greater prevalence of osteoporosis (p=0.002), the postsurgery T-scores were significantly lower (p<0.001) than those at baseline. The SBAC-L1 was significantly lower after surgery than before surgery (p=0.008). According to multivariate analysis, no risk factor was significantly associated with the development of bone fragility at 3 years. The correlation between CT and DXA results was positive and moderate to strong (0.53 to 0.63). Conclusion: There was a significantly greater prevalence of osteoporosis and a lower SBAC-L1 3 years after bariatric surgery than before.