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.

No Differences in Metabolic Parameters Between Roux-en-Y Gastric Bypass and Sleeve Gastrectomy, Regardless of Achieved Weight Loss

Background: Roux-en-y (RYGB) is considered a procedure with more malabsorptive impact than sleeve Gastrectomy (SG), so the risk of chronic complications seems greater. Aim: To describe the metabolic profile and weight regain of patients who underwent bariatric surgery, according to each procedure. Method: A retrospective cohort with patients who underwent bariatric surgery (2003–2018). The sample was divided into SG group and RYGB group. Comparisons were made to analyze the relationship between the procedure itself and metabolic improvements, weight loss and weight regain. Results: We included 117 eligible participants (91.5 % female, 51.2% RYGB surgery), mean follow-up was 4.4± 3.3 years. Mean age was 41.8±6.8 years, without significant difference between the groups. Before the surgery, the groups were similar according metabolic profile (fasting glucose, Hba1c, total cholesterol, LDLc, triglycerides and HOMA IR), except by non-HDLc (RYGB 108.8±26.3 vs SG 127.2±33.2 mg/dl, p=0,002) and 25OHD (RYGB 28.9±4,7 vs SG 34.3±9,5 ng/ml, p=0.044). The RYGB group had greater weight than the SG group (mean 114.1±13.5 kg vs 122.7±20.5 Kg, p&lt;0.0001) and almost 23.3% of the participants had T2DM and 36.2% of them had systemic arterial hypertension, without significant difference between the groups. The RYGB group had a greater postoperative time than the SG group (mean 5.0±4.0 vs 3.6± 2.9 years, respectively). After the surgery, although weight loss was greater in the RYGB group than the SG group (mean 39%±10.2 vs 34.1%±9.8, p&lt;0.0001, respectively), both groups were similar regarding BMI, body fat percentage (BFP) and abdominal circumference. Also, there were no differences in the metabolic profile (fasting glucose, Hba1c, HOMA IR, leptin, triglycerides and HDLc), according to the type of surgery, except in the total cholesterol and LDLc levels (RYGB 167.9±28.2 vs SG 187.9±35.1 and RYGB 92.6±25.6 vs SG 109.5±30.8). Nearly the whole sample (95%) has reached &gt; 20% weight loss. Despite that, 37.6% of the patients have regained &gt; 20% of weight loss, with no relation regarding the type of surgery. Only 7% of the patients remained with some degree of glucose intolerance, with no difference between the groups. Conclusion: We found similar benefits among metabolic markers and weight regain after SG, compared to RYGB.

On the effects of intercalators in DNA condensation: a force spectroscopy and gel electrophoresis study

In this work we have characterized the effects of the intercalator ethidium bromide (EtBr) on the DNA condensation process by using force spectroscopy and gel electrophoresis. We have tested two condensing agents: spermine (spm(4+)), a tetravalent cationic amine which promotes cation-induced DNA condensation, and poly(ethylene glycol) (PEG), a neutral polymer which promotes DNA ψ-condensation. Two different types of experiments were performed. In the first type, bare DNA molecules disperse in solution are first treated with EtBr for intercalation, and then the condensing agent is added to the sample with the purpose of verifying the effects of the intercalator in hindering DNA condensation. In the second experiment type, the bare DNA molecules are first condensed, and then the intercalator is added to the sample in order to verify its influence on the previously condensed DNA. The results obtained with the two different experimental techniques used agree very well, indicating that previously intercalated EtBr can hinder both cation-induced and ψ-condensation, being more efficient in the first case. On the other hand, EtBr has little effect on the previously formed cation-induced condensates, but is efficient in unfolding the ψ-condensates.