Association of preoperative hemoglobin with weight loss after bariatric surgery: a retrospective study

Factors associated with different patterns of weight change after bariatric surgery: A longitudinal study

Background

The mean weight loss (WL) after successful bariatric surgery is approximately one third of the initial body weight, which is mainly achieved between the first 2 years of follow-up. However, 15%-35% of patients do not achieve a significant percentage of total WL (%TWL). Information on factors associated with a higher or lower WL after bariatric surgery is limited. This study aimed to assess the change in %TWL and describe the factors associated with greater or lesser WL over time.

Methods

This prospective longitudinal study included patients treated with laparoscopic Roux-en-Y gastric bypass or sleeve gastrectomy. Baseline data were recorded before surgery. Follow-up was performed at 3 (n = 141), 6 (n = 208), 9 (n = 115), 12 (n = 216), 24 (n = 166), and 36 months (n = 99). Generalized estimating equation analysis was performed to assess the changes in %TWL over time and factors associated with different patterns of WL.

Results

In total, 231 patients were included (women, 82.2%; basal body mass index (BMI) 41.4 ± 5.1 kg/m2). The tendencies to increase %TWL (32 ± 6.5) were evident in the first year and stabilized thereafter. Sustained nutritionist follow-up (2.3%, p = 0.004), baseline BMI >40 kg/m2 (0.4%, p < 0.001), and WL ≥ 10 kg before surgery (0.3%, p = 0.001) were associated with a higher %TWL. Patients who performed physical activity >30 min/day after surgery reduced their %TWL by 0.6% (p = 0.002).

Conclusions

Modifiable factors such as nutritional monitoring and WL before surgery are associated with a significant increase in %TWL over time. Basal BMI was associated with a significant decrease in %TWL.

Excessive weight loss after bariatric surgery: a prediction model retrospective cohort study

Bariatric surgery has been recognized as the most effective long-term treatment for morbid obesity. Despite the considerable positive results, adverse consequence can develop. Excessive Weight Loss (EXWL), a rare consequence of bariatric surgery, can lead to a broad adverse consequence. The aim of this study was determining of prevalence and the predicting model of EXWL in patient underwent bariatric surgery until 24 months after surgery. Data have been extracted from the National Obesity Surgery Database in obesity clinic of Iran University of Medical Sciences. The subjects of this retrospective cohort study were morbid obese individuals who underwent three various types of bariatric surgery [One Anastomosis Gastric Bypass (OAGB), Roux-en-Y Gastric Bypass (RYGB), or Sleeve Gastrectomy (SG)] in period of 24 months ago. EXWL has been defined as reaching to less than or equal to BMI 18.5 at any time until 24 months after surgery. SPSS was used in data analysis. Among 4214 subjects of this study, most excess weight loss after surgery has taken place in 18 months after surgery. 11.4% (n = 495) of patients experienced EXWL with highest percentage among OAGB patients (15.1%) at time of 24 months after surgery. The females (20.4% vs.9.9%) and younger persons (35.45 ± 10.25 vs. 39.06 ± 10.76) were more susceptible to EXWL. Patients with EXWL had significantly lower BMI (body mass index) (41.11 ± 4.51 vs. 46.73 ± 6.26) (Kg/m²), and were less probable to had emotional eating. Visceral fat level, fat percentage, and BMI were the best predictor of EXWL (P value for all < 0.05). So that per level increase in visceral fat, decreases the probability of EXWL as 47% and 61% in SG and OAGB. Moreover, each unit lower BMI leads to 25% higher susceptibility to experience EXWL. Surgery should be adjusted in younger females with a lower BMI and healthy metabolic status who are more prone to EXWL. In such a way that minimize weight loss speed/value. It may be possible by selection of other surgery procedures, rather than OAGB, tighter follow-ups, and consultations of patients after surgery is emphasized for more EXWL vulnerable patients.

New concepts in the diagnosis and management approach to iron deficiency in candidates for metabolic surgery: should we change our practice?

The near universal presence of chronic low-grade systemic inflammation among patients with severe obesity disrupts iron homeostasis and underlies the association between obesity and iron deficiency. Immune activation and inflammation result in a reduction in circulating iron and diminished iron bioavailability for erythropoiesis. Inflammation also alters blood levels of commonly measured markers of iron nutrition status, which makes the diagnosis of iron deficiency difficult and has led to new recommendations regarding laboratory markers for the diagnosis. Recent evidence using these newly recommended laboratory markers, which include levels of ferritin, C-reactive protein, and transferrin saturation, suggests that the actual prevalence of iron deficiency among candidates for metabolic surgery may be double or triple the prevalence identified by low levels of ferritin alone. Thus large numbers of surgical candidates have iron deficiency that has been heretofore largely unrecognized and inadequately treated. The assessment of iron status using the currently recommended markers in the presence of chronic inflammatory diseases and repletion of depleted stores for surgical candidates with deficiency during the preoperative period present an important opportunity for mitigating this condition in postoperative patients.