Prevalence of Morphometric Vertebral Fractures After Bariatric Surgery and Its Relationship with Bone Mineral Density and Bone Markers

BACKGROUND

Bariatric surgery (BS) can lead to bone loss and an increased fracture risk.

METHODS

To determine the morphometric vertebral fracture (MVF) prevalence, and its relationship with bone mineral density (BMD), and biomarker's turnover after Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (SG), we analyzed post-surgery X-rays of the spine in 80 patients (88% female, 51% RYGB, age 41.2 [6.8] years) from 117 participants' retrospective cohort (1-2 years, >2 and <5 years, and >5 years). We still analyzed body composition and BMD by dual-energy X-ray absorptiometry and bone parameters.

RESULTS

MVF prevalence was 17.5% (14/80), with no statistical difference between groups (p = 0.210). RYGB group had a higher prevalence of secondary hyperparathyroidism (SHPT) (PTH ≥ 65 pg/ml; 18.4% vs 7.8%, respectively, p = 0.04), PTH (61.3 vs 49.5 pg/ml, p = 0.001), CTX (0.766 [0.29] ng/ml vs 0.453 [0.30] ng/ml, p = 0.037), and AP (101.3 [62.4] U/L vs 123.9 [60.9] U/L, p = 0.027) than the SG group. Up to 5 years postoperatively, RYGB had a lower total (1.200 [0.087] vs 1.236 [0.100] g/cm2, p = 0.02), femoral neck (1.034 [0.110] vs 1.267 [0.105], p = 0.005), and total femur BMD (1.256 [0.155] vs 1.323 [0.167], p = 0.002) than SG group. We found no statistically significant difference between the MFV (+) and MVF (-) groups regarding age, sex, BMI, surgery time, BMD, or bone and metabolic parameters, including leptin.

CONCLUSION

We found a high prevalence of MVF after BS with no differences between RYGB and SG.

Vitamin D Concentration Changes after Bariatric Surgery

Introduction

Bariatric surgery causes physiological and anatomical changes in the gastrointestinal tract that interfere with intestinal absorption and, consequently, with the nutritional status, especially about vitamin D. The aim of the study was to evaluate the vitamin D levels and body composition of these patients in the Roux-en-Y gastric bypass (RYGB) and vertical sleeve gastrectomy (VSG) types of surgery.

Methods

The retrospective cohort study included a population of 120 patients aged between 18 and 65 years, with class II or III obesity, undergoing bariatric surgery procedures (VSG or RYGB-type). Data were collected on the degree of obesity, age, average time since surgery, and gender. The individuals underwent a complete physical examination, measuring blood pressure, weight, height, waist, and neck circumference. In addition to calculating the percentage of loss of body weight and assessing body fat, the food frequency and physical activity of these patients were evaluated. Blood was collected, and the insulin variables, hydroxyvitamin D (25OHD), were analyzed.

Results

There was a significant difference between groups only for PTH, total BMD, and insulin variables. A significant intragroup difference was found in the variables' body mass index (BMI) and vitamin D for the vertical sleeve gastrectomy group and BMI for the RYGB group.

Conclusion

The analysis between the groups of procedures, similarity in body composition and postsurgical vitamin D levels, with significant differences only for PTH, BMD, and insulin variables, demonstrates that both procedures are effective in reducing fat mass.

Definition and management of very high fracture risk in women with postmenopausal osteoporosis: a position statement from the Brazilian Society of Endocrinology and Metabolism (SBEM) and the Brazilian Association of Bone Assessment and Metabolism (ABRASSO)

Several drugs are available for the treatment of osteoporosis in postmenopausal women. Over the last decades, most patients requiring pharmacological intervention were offered antiresorptive drugs as first-line therapy, while anabolic agents were considered a last resource for those with therapeutic failure. However, recent randomized trials in patients with severe osteoporosis have shown that anabolic agents reduce fractures to a greater extent than antiresorptive medications. Additionally, evidence indicates that increases in bone mineral density (BMD) are maximized when patients are treated with anabolic agents first, followed by antiresorptive therapy. This evidence is key, considering that greater increases in BMD during osteoporosis treatment are associated with a more pronounced reduction in fracture risk. Thus, international guidelines have recently proposed an individualized approach to osteoporosis treatment based on fracture risk stratification, in which the stratification risk has been refined to include a category of patients at very high risk of fracture who should be managed with anabolic agents as first-line therapy. In this document, the Brazilian Society of Endocrinology and Metabolism and the Brazilian Association of Bone Assessment and Metabolism propose the definition of very high risk of osteoporotic fracture in postmenopausal women, for whom anabolic agents should be considered as first-line therapy. This document also reviews the factors associated with increased fracture risk, trials comparing anabolic versus antiresorptive agents, efficacy of anabolic agents in patients who are treatment naïve versus those previously treated with antiresorptive agents, and safety of anabolic agents.

Secondary Hyperparathyroidism, Bone Density, and Bone Turnover After Bariatric Surgery: Differences Between Roux-en-Y Gastric Bypass and Sleeve Gastrectomy

PURPOSE

Bariatric surgery may lead to metabolic bone disease.

MATERIALS AND METHODS

In this cross-sectional study, we compared the prevalence of secondary hyperparathyroidism (SHPT), impact on bone mass and turnover markers, and serum leptin after Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (SG) in 117 patients (91% female, 51% RYGB, age 41.8 ± 6.7 years, time of surgery 4.3 ± 3.4 years) at different times (1-2 years, > 2 and < 5 years and ≥ 5 years). Body composition, bone mineral density (BMD), by dual-energy X-ray absorptiometry, and bone parameters (PTH, serum calcium, 25OHD, alkaline phosphatase (AP), C-telopeptide (CTX)) were analyzed.

RESULTS

Prevalence of SHPT (PTH ≥ 65 pg/ml) was 26%, RYGB > SG (18.4% vs. 7.8%, p = 0.039), despite similar 25OHD and calcium levels. Mean PTH, CTX, and AP were higher in RYGB vs. SG (61.3 ± 29.5 vs 49.5 ± 32.3 pg/ml, p = 0.001; 0.596 ± 0.24 vs. 0.463 ± 0.23 ng/ml; 123.9 ± 60.8 vs. 100.7 ± 62.0 U/l). There were 13.5% decreases in femoral neck BMD in all patients, over the study period. In the last group, the RYGB group showed greater bone loss in total body BMD (1.016 vs. 1.151 g/cm², - 8.1%, p = 0.003) and total femur BMD (1.164 vs. 1.267 g/cm², - 11.7%, p = 0.007). Mean leptin was lower in the RYGB vs. SG group, with no correlation with BMD in any site.

CONCLUSION

Our data suggest a more deleterious role of RYGB on bone remodeling up to 5 years postoperatively in comparison with SG.

Fracture Risk After Bariatric Surgery: A Systematic Literature Review and Meta-Analysis

OBJECTIVE

Bariatric surgery has undeniable benefits for cardiovascular and metabolic health, but it can result in negative effects on mineral and bone metabolism. This study aimed to review the current data on fractures after the main types of bariatric surgery.

METHODS

Therefore, a systematic review was performed using the electronic literature available in the databases LILACS, CENTRAL, Web of Science, Embase, and PubMed/MEDLINE, with results until January 2021. Keywords were descriptors for bariatric surgery or bariatric medicine or bariatrics or gastroplasty and bone or bones or bone fractures, referenced in all words of the text in the study.

RESULTS

The meta-analysis of observational studies and interventional trials showed that the risk of any type of fracture was higher in the surgical group than in the nonsurgical group (relative risk [RR], 1.20 [95% confidence interval {CI}, 1.15-1.26; P < .00001; Phetero < 0.000001; I² = 94%], and RR, 1.16 [95% CI, 1.00-1.33; P = .04; Phetero = 0.27; I² = 23%], respectively). It is worth noting that the included interventional studies have a low rating on the risk of bias assessment scales. Compared with those who underwent restrictive procedures, subjects had an increased fracture risk after malabsorptive procedures (RR, 0.49 [95% CI, 0.40-0.61; P < .00001); Phetero = 0.96; I² = 0%).

CONCLUSION

We found that bariatric procedures are associated with an increased risk of fractures, especially the malabsorptive techniques.