DXA evaluation of bone fragility 2 years after bariatric surgery in patients with obesity.

Purpose: The primary objective was to evaluate bone fragility on dual X-ray absorptiometry (DXA) in patients with obesity before and 2 years after bariatric surgery. The secondary objective was to identify risk factors for the development of a bone mineral density ≤ -2 SD at 2 years. Methods: This descriptive study included patients with obesity who underwent DXA before and 2 years (±6 months) after bariatric surgery. The BMD and the T-score were assessed at the lumbar spine, femoral neck and total hip. Data on body composition on DXA were also collected. The diagnosis of osteoporosis was retained for a T-score ≤ - 2.5 SD at any measured location. Osteopenia, or low bone mass, was defined by -2.5 SD < T-score ≤ -1 SD. Results: Among the 675 included patients, 77.8 % were women, with a mean age of 49.5 years (±11.1). After bariatric surgery, there were significantly more patients with osteoporosis: 3.6 % vs. 0.9 % (p = 0.0001). Multivariate analysis revealed that the risk factors for developing a bone mineral density ≤ -2 SD 2 years after bariatric surgery in patients with normal BMD before surgery were age and lower lean and fat mass before the surgery (OR = 1.07, 95%CI = [1.03-1.12], OR = 0.83, 95%CI = [0.77-0.91], OR = 1.08, 95%CI = [1.02-1.15], respectively). Conclusion: There was a significantly higher prevalence of osteoporosis and low bone mass 2 years after bariatric surgery. Older age and lower lean and fat mass at baseline were risk factors for the development of a BMD ≤ -2SD at 2 years.

CT evaluation of bone fragility 2 years after bariatric surgery: an observational study.

INTRODUCTION: The objectives were to evaluate bone fragility on computed tomography (CT) in patients with obesity before and 2 years after bariatric surgery and to identify risk factors for a decrease in the scanographic bone attenuation coefficient of the first lumbar vertebra (SBAC-L1). MATERIALS AND METHODS: Patients with obesity who underwent bariatric surgery and CT before and 2 years (± 6 months) after bariatric surgery were included. SBAC-L1 was measured on CT with a fracture threshold at 145 HU. RESULTS: 78 patients were included, 85.9% women, mean age of 48.5 years (± 11.4); the mean BMI was 46.2 kg/m2 (± 7) before surgery and 29.8 kg/m2 (± 6.7) 2 years after surgery. There was a significant change in SBAC-L1 2 years after surgery (p = 0.037). In multivariate analysis, the risk factors for having an SBAC-L1 ≤ 145HU 2 years after bariatric surgery in those with an SBAC-L1 > 145HU before surgery were age and sex, with men and older patients having a higher risk (OR 32.6, CI 95% [1.86-568.77], and OR 0.85, CI 95% [0.74-0.98], respectively). CONCLUSION: SBAC-L1 was significantly lower two years after bariatric surgery. Men sex and older patients were the risk factors for having an SBAC-L1 below the fracture threshold 2 years after surgery.

Prevalence of Osteoporosis Assessed by DXA and/or CT in Severe Obese Patients.

The primary objective was to evaluate bone fragility prevalence on dual X-ray absorptiometry (DXA) and computed tomography (CT) in patients with severe obesity. The secondary objective was to evaluate the risk factors for bone fragility. This monocentric study was conducted in patients with grade 2 and 3 obesity. Bone mineral density (BMD) and T-score were studied on DXA, and the scanographic bone attenuation coefficient of L1 (SBAC-L1) was measured on CT. Among the 1386 patients included, 1013 had undergone both DXA and CT within less than 2 years. The mean age was 48.4 (±11.4) years, 77.6% were women, and the mean BMI was 45.6 (±6.7) kg/m². Eight patients (0.8%) had osteoporosis in at least one site. The mean SBAC-L1 was 192.3 (±52.4) HU; 163 patients (16.1%) were under the threshold of 145 HU. Older age (OR[CI95] = 1.1 [1.08-1.16]), lower BMD on the femoral neck and spine (OR[CI95] = 0.04[0.005-0.33] and OR[CI95] = 0.001[0.0001-0.008], respectively), and higher lean mass (OR[CI95] = 1.1 [1.03-1.13]) were significantly associated with an SBAC-L1 ≤ 145 HU in multivariate analysis. Approximately 16% of patients with severe obesity were under the SBAC-L1 threshold, while less than 1% were classified as osteoporotic on DXA.