Introduction

The prevalence of obesity is increasing worldwide and according to World Health Organisation (WHO) 650 million people were reported as obese in 2016 and the number has tripled since 1975 [1]. According to World Obesity Federation, prevalence of obesity in United Arab Emirates (UAE) is reported as 27.8% between age of 18-69 years in 2017-2018 [2]. There are many treatment options available for management of obesity, including physical activity, dietary intervention, behavior therapy, pharmacological treatment and bariatric surgery. Bariatric surgery however, is an effective treatment of severe obesity and as a result the number of bariatric surgeries that are being performed has increased in recent years. According to 4^th International Federation for the surgery of obesity and metabolic disorders (IFSO) Global registry report 634,897 bariatric surgeries were performed worldwide in 2016 [3]. Bariatric surgery has shown improved longterm metabolic outcomes in patients with obesity [4,5]. The aim of our study was to look at anthropometric measurements and metabolic outcomes of our cohort at 12 months postoperatively.

Methods

This is a retrospective cohort study of sixty-nine patients who underwent bariatric surgery at Mediclinic Parkview Hospital in Dubai, UAE between January 2019-September 2021 as part of a multi-disciplinary weight management program. Patients were screened for inclusion/exclusion criteria according to the American Society for Metabolic and Bariatric Surgery (ASMBS) guidelines [6]. The ASMBS inclusion criteria for bariatric surgery candidates are:

1-Patients with BMI ≥ 40 kg/m².

2. With BMI 35–40 kg/m2 with co-morbidities e.g type 2 diabetes, hypertension, hyperlipidemia, Obstructive Sleep Apnea (OSA), Non-Alcoholic Steatohepatitis (NASH), Non-Alcoholic Fatty Liver Disease (NAFLD).

3-Patients with BMI 30-34.9 kg/m² with recent onset type 2 diabetes or metabolic syndrome may be offered bariatric procedure.

Patients were excluded from the bariatric surgery based on exclusion criteria, which are as follows: current drug or alcohol abuse; any underlying reversible endocrine disorder causing obesity; severe psychiatric illness; and lack of comprehension of the risks/benefits/expected outcomes/lifestyle changes associated with bariatric surgery.

Data Collection

Data was collected from electronic medical records Bayanaty^® (InterSystems IRIS, US) and the body composition analyzer (Seca^®, Germany). Data collection was done as follows: Demographic data included age, gender and nationality. Anthropometric measures included height, weight, BMI, fat mass, body fat percentage, visceral fat mass, WC, HC and WHR at baseline, 3,6 and 12 months post-operatively. Laboratory measurements included glycated haemoglobin (HbA1c), renal function such as Estimated Glomerular Filtration Rate (eGFR), liver function tests including AST and ALT, lipid profile including cholesterol, triglyceride, LDL, and HDL at baseline, 3, 6 and 12 months post-operatively.

Data Analysis

Data were analyzed using IBM-SPSS for Windows version 28.0 (SPSS Inc., Chicago, IL). Categorical variables are described by using proportions. Continuous variables are described by a measure of tendency and a measure of dispersion. Continuous data was tested for normality by using the Shapiro-Wilk test. Friedman's one-way ANOVA was used to compare between related data in more than two groups. A P-value of less than 0.05 was considered significant for all analyses.

Ethical Statement

Ethical approvals were taken from local Mediclinic Institutional Research Board; and Dubai Scientific Research Ethics Committee, Dubai Health Authority, Dubai, UAE.

Results

Table 1 shows baseline characteristics of patients. Sixty-nine patients were included in this retrospective cohort study. About 24 (34.8%) were males and 45 (65.2%) were females. The mean age was 41 years (±10.8) with a BMI of 41.87 (±10.3). Majority were from Asian ethnicity (n=25/69, 36.2%) with Middle Eastern and North-East African and Western ethnicity making up the rest of the cohort.

Table 3 shows changes in anthropometric measurements at baseline, 3, 6 and 12 months post-operatively. Mean baseline BMI was 41.87 ± 10.33 kg, which significantly dropped to 36.15 ± 10.51, 33.27 ± 8.94 and 30.16 ± 6.11 at 3, 6 and 12 months respectively, and this change was statistically significant P 0.003. Similarly, visceral fat was 5.76 ± 3.70 at baseline dropped to 4.34 ± 3.14, 3.31 ± 2.08 and 2.70 ±1.82 at 3, 6 and 12 months respectively (P<0.001)

Table 4 shows changes in laboratory measurements at baseline, 3, 6 and 12 months post-operatively. Lipid profile improved at 12 months postoperatively with Total Cholesterol (TC), Triglycerides (TG) and Low Density Lipoproteins (LDL) dropping from 9.26 ± 30.6 to 4.98 ± 0.92, 1.71 ± 1.08 to 1.02 ± 0.26 and 3.50 ± 0.93 to 3.4 ± 0.98 respectively. (P<0.08) AST and ALT improved from 27.85 ± 18.39 to 15.24 ± 4.07 and 40.58 ± 35.49 to 17.84 ± 7.37 respectively at 12 months postoperatively.

29 patients didn’t come for follow up after 1 year, n=20/69 (42%). Out of these, 2 patients were followed up in Abu Dhabi.7 patients were from medical tourism, n=7/69 (10%), 3 patients went back to United Kingdom, 2 to Canada, 1 to United States and 1 to Nigeria. Detailed medical reports were given to patients for follow up in their respective countries. N=9/13 (69.2%) patients prediabetes was resolved, 7 patients didn’t have follow up at one year as they were from medical tourism. N= 5/7 (71.4%) patients type 2 diabetes was resolved with normal HbA1c. 4 patients were on oral hypoglycaemic medications which were stopped and one patient discontinued insulin post operatively at one 1 year follow up. One patient had sepsis secondary to post-operative peritonitis which required antibiotics and conservative management.

Discussion

This was a retrospective study which showed statistically significant reduction in BMI, fat mass, visceral fat and waist circumference from baseline  to 12 months post-operatively. Fat mass reduced from 59.28±22.72 to 34.77±17.22, Visceral fat reduced from 5.76±3.70 to 2.70±1.82 at 12 months and WC reduced from 118.82±17.03 to 100.59±.11.36 at 12 months (p values <0.001). Our study has shown 24.5 kg (41.3%)reduction in fat mass and 3 kg (52%) reduction in visceral fat at 12 months. Abusanana et al demonstrated 46% reduction in fat mass and Ciangura et al showed 45.2% decrease in fat mass but in Roux en Y gastric bypass procedure whereas in our study laproscopic sleeve gastrectomy was the main procedure [7,8]. Eduardo et al in 2021 has shown a decrease in visceral fat at 6 months after surgery in both men and women (Baseline 7.5 ± 3L,  6 months 2.5 ± 2 L (p = 0.001). An average decrease in visceral adipose tissue of 70 ± 22% in women and 60 ± 21% in men (p = 0.53) 6 months after surgery. The highest percentage of visceral fat at 6 months was seen with Laparoscopic One-Anastomosis Gastric Bypass (OAGB), however, this was not statistically significant when compared with Y-Roux Gastric bypass (YRGB) [9]. Bhatti et al has already shown that there is strong correlation between visceral fat, waist circumference and risk of metabolic disease [10]. Lipid profile improved at 12 months postoperatively with total cholesterol, triglycerides and Low Density Lipoproteins (LDL) dropping from 9.26 ± 30.6 to 4.98 ± 0.92 (P<0.08), 1.71 ± 1.08 to 1.02 ± 0.26 (P<0.09) and 3.50 ± 0.93 to 3.4 ± 0.98 respectively. (P<0.2), however it was not statistically significant. Similar results were shown by meta-analysis published by Heffron et al. In post sleeve gastrectomy subjects, there was non-significant reduction in mean TC at one year compared with baseline (P=0.11), reduction in LDL (P=0.13) [10]. AST and ALT improved from 27.85 ± 18.39 to 15.24 ± 4.07 and 40.58 ± 35.49 to 17.84 ± 7.37 respectively at 12 months postoperatively [11].

71.4% of patients with type 2 diabetes and 69.2% of patients with prediabetes had normalization of HbA1c at 1 year. Similar results are shown in other studies like 59.2% (95% CI, 57.7%-60.7%) of patients who had RYGB vs 55.9% (95% CI, 53.9%-57.9%) of those who had Sleeve gastrectomy experienced remission by 1 year [12].

42% of patients were lost to follow up, out of which 7/29 (24.1%) were from medical tourism and 2 were followed up in another emirate. This reflects the fact that Dubai is a very multi-national society with more than 200 nationalities. Limitations of our study include the small sample size and retrospective nature of analysis. Therefore, more studies with large sample size would help in this guidance. Another limitation of our study is there are more patients with laproscopic sleeve gastrectomy compared to other procedures so we cannot look at outcomes based on type of procedure performed.

Conclusions

The results show that bariatric surgery was effective in achieving weight loss in terms of reduction in BMI, fat mass, visceral fat, waist circumference as well as improvement in lipid and liver profile over a follow up period of one year. Further studies are needed to see whether favorable outcomes of bariatric surgery can be sustained over long term in this mixed population.

Tables

Table 1: Baseline characteristics of patients.

Table 2: Co-morbidities.

Table 3: Changes in Anthropometric Meaurements.

Table 4: Changes in laboratory measurements.

References

1. World Health Organization. Health topics: obesity. Geneva, Switzerland: World Health Organization 2014.
2. World Obesity Federation 2022.
3. Angrisani L, Santonicola A, Iovino P, Vitiello A, Higa K, et al. (2018) IFSO Worldwide Survey 2016: Primary, Endoluminal, and Revisional Procedures. Obes Surg 28: 3783-3794.
4. Schauer PR, Kashyap SR, Wolski K, et al. (2012) Bariatric surgery versus intensive medical therapy in obese patients with diabetes. N Engl J Med 366: 1567-1576.
5. Buchwald H, Avidor Y, Braunwald E, Jensen MD, Pories W, et al. (2004) Bariatric surgery: a systematic review and meta-analysis. JAMA 292: 1724-1737.
6. Mechanick JI, Youdim A, Jones DB, et al. (2013) Clinical practice guidelines for the perioperative nutritional, metabolic, and nonsurgical support of the bariatric surgery patient – 2013 update: cosponsored by American Association of Clinical Endocrinologists, The Obesity Society, and American Society for Metabolic and Bariatric Surgery. Obesity (Silver Spring) 1: S1-S27.
7. Abusnana S, Abdi S, Tagure B, Elbagir M, Maleckas A (2015) Bariatric surgery outcomes: a single-center study in the United Arab Emirates. Diabetes Metab Syndr Obes 8: 461-471.
8. Ciangura C, Bouillot JL, Lloret-Linares C, et al. (2010) Dynamics of change in total and regional body composition after gastric bypass in obese patients. Obesity (Silver Spring) 18: 760-765.
9. Eduardo Doval, Susana Reyes Lopez, Alejandra Albarran , Ernesto Sosa, Claudia Ramirez, et al. (2021) Changes in Visceral Fat and Its Correlation With Changes in Metabolic Variables After Bariatric Surgery 5.
10. Bhatti R, Warshow U, Joumaa M, ElSaban M, Nawaz FA, et al. (2021) Relevance of Anthropometric Measurements in a Multiethnic Obesity Cohort: Observational Study. Interact J Med Res 10: e27784.
11. Heffron SP, Parikh A, Volodarskiy A, Ren-Fielding C, Schwartzbard A, et al. (2016) Changes in Lipid Profile of Obese Patients Following Contemporary Bariatric Surgery: A Meta-Analysis. Am J Med 129: 952-959.
12. McTigue KM, Wellman R, Nauman E, et al. (2020) Comparing the 5-Year Diabetes Outcomes of Sleeve Gastrectomy and Gastric Bypass: The National Patient-Centered Clinical Research Network (PCORNet) Bariatric Study. JAMA Surg 155: e200087.