|Year : 2021 | Volume
| Issue : 1 | Page : 76-82
Effects of metabolic surgery on energy and nutrient intake in obese asian indians with dysglycemia
Sundaramoorthy Chandru1, Narasimhan Sowmya2, Rajendra Pradeepa3, Suresh Thangamani3, Thyparambil Aravindakshan Pramodkumar3, Gopalakrishna Pazhanithampi3, Ramesh Aiswarya3, Ranjit Mohan Anjana3, Viswanathan Mohan3
1 Madras Diabetes Research Foundation and Dr. Mohan’s Diabetes Specialities Centre, Chennai, India; University of Madras, Chennai, India
2 Quaid-E-Millath Government College for Women, Chennai, India
3 Madras Diabetes Research Foundation and Dr. Mohan’s Diabetes Specialities Centre, Chennai, India
|Date of Submission||07-Aug-2020|
|Date of Decision||20-Aug-2020|
|Date of Acceptance||24-Aug-2020|
|Date of Web Publication||25-Dec-2020|
Dr. Sundaramoorthy Chandru
MD, Dr. Mohan’s Diabetes Specialities Centre Research Fellow, Madras Diabetes Research Foundation, ICMR Centre for Advanced Research on Diabetes, No. 4, Conran Smith Road, Gopalapuram, Chennai 600086.
Source of Support: None, Conflict of Interest: None
Aims and Objectives: The rising prevalence of obesity and consequent metabolic disorders like type 2 diabetes has resulted in an increase in the number of metabolic surgeries. However, the nutrient intake of subjects who have undergone metabolic surgery remains poorly investigated in Asian Indians. The study aimed to assess the nutrient intake of obese Asian Indians who underwent metabolic surgery. Materials and Methods: Thirty obese Asian Indians with dysglycemia who underwent metabolic surgery at a tertiary diabetes center in South India were selected. Anthropometric, clinical, and biochemical measures were collected using standard methods. Using 24-h recalls, data were obtained on the nutrient intakes at baseline and 1, 6, and 12 months after surgery. Results: A significant decline was observed at the end of 6 and 12 months in all anthropometric characteristics such as body mass index, waist circumference, and hip circumference (P < 0.001). The mean daily energy intake at baseline (1371 ± 665 kcal) decreased significantly after 6 months (671 ± 423) and 12 months (847 ± 463). There was a significant decrease after 6 and 12 months in the intake of total carbohydrate, protein, and fat compared to baseline (P < 0.001). At the end of 12 months, energy intake was 70% as compared to baseline (100%), while that of carbohydrate was 62%, protein 75%, and fat 83%. Conclusion: Metabolic surgery resulted in a significant decline in energy intake, which is essential for postoperative weight loss and maintenance. There is also undesirable loss of soft lean mass (SLM); hence, strategies are needed to prevent the muscle loss.
Keywords: Diabetes, energy, macronutrient, metabolic surgery, obesity
|How to cite this article:|
Chandru S, Sowmya N, Pradeepa R, Thangamani S, Pramodkumar TA, Pazhanithampi G, Aiswarya R, Anjana RM, Mohan V. Effects of metabolic surgery on energy and nutrient intake in obese asian indians with dysglycemia. J Diabetol 2021;12:76-82
|How to cite this URL:|
Chandru S, Sowmya N, Pradeepa R, Thangamani S, Pramodkumar TA, Pazhanithampi G, Aiswarya R, Anjana RM, Mohan V. Effects of metabolic surgery on energy and nutrient intake in obese asian indians with dysglycemia. J Diabetol [serial online] 2021 [cited 2021 Apr 12];12:76-82. Available from: https://www.journalofdiabetology.org/text.asp?2021/12/1/76/304359
| Introduction|| |
The rapidly rising prevalence of obesity has been attributed to the nutrition transition, resulting in modifications in lifestyle and dietary patterns., Indeed, obesity presents a major national and global public health challenge, besides posing a greater risk for diabetes and other metabolic disorders. According to the World Health Organization (WHO), the global prevalence of obesity among adults aged ≥18 years in 2016 was 13%. Metabolic surgery is emerging as a successful treatment modality for obesity because of greater short-term weight loss and reduction in comorbidities compared to conventional methods. The common metabolic procedures include gastric banding, Roux-en-Y gastric bypass (RYGB), and sleeve gastrectomy (SG), which reduce and maintain weight by restricting the intake of food, malabsorption of food, or both. However, metabolic surgical procedures can cause nutritional deficiencies due to inadequate preoperative intakes, malabsorption, and ineffective nutrition intervention., Furthermore, improper nutrient intakes can also result in a reversal of weight loss and comorbidities, which highlights the importance of postoperative nutrient intakes.
Studies indicate that the level of dietary adherence within the first year of the postoperative period is a significant predictor of weight loss over time. To date, many such studies have been undertaken in the western population, but findings in the Indian context are limited. As postoperative weight loss and maintenance depend mainly on energy and macronutrient intakes, the Indian diet, with its traditional high carbohydrate intake, presents a real challenge. Therefore, we assess the nutrient intake of obese patients who have undergone metabolic surgery.
| Materials and Methods|| |
This is a prospective study of all obese individuals with comorbidities who underwent metabolic surgery between November 2013 and March 2019 at Dr. Mohan’s Diabetes Specialities Centre in Chennai, South India. Of the 36 individuals who underwent metabolic surgery, 30 individuals (15 diversionary procedure and 15 SG) consented to take part in the study and come for regular follow-up for 1 year.
For all individuals, anthropometric and clinical measurements, and biochemical investigations were done using standardized methods. All biochemical parameters were estimated at Dr. Mohan’s Diabetes Specialities Centre laboratory, which is certified by the College of American Pathologists and the National Accreditation Board for Testing and Calibration of Laboratories (NABL). A fasting venous blood sample was collected after an overnight fast of at least 10h for the estimation of fasting glucose and lipids and, after a standard South Indian breakfast, a 2h postprandial sample was obtained for postprandial plasma glucose estimation. Analysis of plasma glucose levels was done using hexokinase method, serum cholesterol by cholesterol oxidase–peroxidase amidopyrine method, serum triglyceride by the glycerol phosphate oxidase–peroxidase amidopyrine method, high-density lipoprotein (HDL) cholesterol by direct method—immunoinhibition, calcium by arsenazo method, iron by tripyridyl-s-triazine, albumin by bromocresol green method, using Beckman Coulter AU 680 (Fullerton, CA, USA) and Beckman kits. Friedewald formula was used to calculate low-density lipoprotein (LDL) cholesterol. HbA1c was measured by high-performance liquid chromatography using the Variant II Turbo (Bio-Rad, Hercules, CA, USA). Folate, Vitamin B12, and Vitamin D were measured by chemiluminescence method using ADVIA centaur XPT (Siemens). The intra- and interassay coefficients of variation for the biochemical assays ranged between 3.1 and 7.6%.
All the participants were given diet counseling before and after surgery. The participants were asked to restrict their energy intakes 1 month prior to surgery. Dietary intakes were estimated using single 24-h recalls collected with the help of visual aids at baseline and the end of 1, 6, and 12 months. The average daily food and nutrient intakes were computed using the in-house Nutritional Epidemiology software (EpiNu) database. During the first month in the postoperative period, the patients were given a liquid diet with gradual progression to a soft solid diet and normal diet, along with a standard vitamin and mineral supplement as per the recommendations. There was no change in the methodology of dietary and biochemical assessments during the conduct of study.
Body composition was measured using Bioelectrical Impedance Assay (BIA) by Jawon IOI 353 (Jawon Medical, Korea Certified by CE, FDA, ENISO 13485 and reports are accredited with WHO and NIH standards). Body composition analysis measures mean body fat (MBF), lean body mass (LBM), soft lean mass (SLM), mass of body fat (MBF), percent of body fat and minerals, visceral fat area, and total body water and protein.
Quantitative variables were described with means and standard deviations. Paired t-test as appropriate was used to compare groups for continuous variables and the χ2 test or Fisher’s exact test as appropriate was used to compare proportions. All analyses were done using the Windows-based SPSS statistical package (version 22.0, SPSS Inc., Chicago, IL) and P <0.05 was considered statistically significant.
Surgical technique used
Currently, metabolic surgery has been broadly classified into restrictive procedures (adjustable gastric banding and SG) and gastrointestinal diversionary procedures (DP) [Rouxen-Y gastric bypass (RYGB), Biliopancreatic diversion (BPD), Single Anastomosis Duodenoileal Bypass with Sleeve (SADI-S), and Sleeve Gastrectomy with Loop Gastroileal Bypass (SG-LGIB)].
Of the 30 individuals, 15 (50%) underwent RP (SG) and 15 underwent DP [RYGB (n = 12) 40%, SADI-S (n = 2) 6.7%, and (SG-LGIB) (n = 1) 3.3%], and the surgeon decided between these procedures which depend on the duration of diabetes, desired weight loss, and other comorbid conditions of the patients.
Ethical approval and patient consent
The study was conducted in accordance with the declaration of the Helsinki and approved by the Institutional Ethical Committee of Madras Diabetes Research Foundation (MDRF/NCT/07-02/2014). Written informed consent was obtained from all the study participants.
| Results|| |
The mean age of the subjects was 44.2 ± 12.8 and 36.7% were males. Of those included in the study, 93% were nonvegetarians. [Table 1] shows the comparison of anthropometric and clinical characteristics of the study participants at baseline and 6 and 12 months after SG and RYGB surgery. Participants in the RYGB group were older and there were more females. As expected, a significant decline was observed at the end of 6 and 12 months in all anthropometric characteristics such as body mass index (BMI), waist circumference, and hip circumference (P < 0.001) in both the groups. Systolic blood pressure decreased significantly in both the groups (P < 0.001) while diastolic blood pressure showed a significant decrease at 6 months in only the RYGB group, which, however, became insignificant at the end of 12 months.
|Table 1: Anthropometric and clinical characteristics of study participants|
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[Table 2] shows the biochemical characteristics of the participants at the end of 6 and 12 months after SG and RYGB surgery. Consequent to the decrease in body weight and BMI, there was a significant improvement in the glycemic status of the participants from both groups as indicated by a decrease in the mean fasting blood and postprandial blood sugar levels, and HbA1c levels. Furthermore, serum triglyceride levels also decreased significantly in both the groups. Total and LDL cholesterol, however, did not differ significantly at the end of 6 or 12 months in both the groups. Compared to baseline, there was a significant increase in the Vitamin D and B12 (after 6 months for SG and 12 months for RYGB, P < 0.001) levels of the participants in both the groups. Though there was an increase in folate levels, it was significant only among those who underwent SG. There was no significant change in serum levels of calcium, iron, or albumin.
The results of the analysis of the nutrient intakes of the participants at 1 month, 6 months, and 12 months after surgery are presented in [Table 3]. During the first month following surgery, all the participants consumed a full liquid diet and gradually progressed to a solid diet. Consequently, the intake of all nutrients was lowest at the end of the first month, which improved significantly at the end of 6 and 12 months, after a normal diet was started. However, these were still lower than the baseline. The mean daily energy intake at baseline was 1371 ± 665 kcal, which decreased significantly after 6 months (671 ± 423) and 12 months (847 ± 463), (P < 0.001). Likewise, there was a significant decrease after 6 and 12 months in the intake of total carbohydrate, protein, and fat compared to baseline (P < 0.001). However, the percentage distribution of calories from the macronutrients did not vary significantly at the end of 12 months. It is to be noted that although the participants had a moderate intake of energy and protein at baseline, intakes of micronutrients such as calcium and iron and dietary fiber were low, which further declined after surgery. No significant difference in the intake of nutrients between the two groups (SG and Diversionary procedure) was observed. At 6 and 12 months post-op, there was a significant reduction from baseline in the MBF (43.1 ± 12.4 vs. 28.8 ± 8.3 vs. 24.4 ± 7.3 kg, P < 0.001), and SLM (53.3 ± 8.6 vs. 47.9 ± 8.1 vs. 45.8 ± 8.8 kg, P < 0.001) which could be the result of metabolic surgery-induced decrease in energy intake.
[Figure 1] shows the percentage of energy and macronutrients intake from baseline to 12 months after surgery. As compared to baseline, maximum decline in energy and macronutrient intakes was observed at the end of the first month (energy 34%, carbohydrate 32%, protein 46%, and fat 27%, P < 0.001) due to the intake of liquid diet. The intake improved significantly at the end of 6 and 12 months as the diet progressed to normal. Thus, at the end of 12 months, energy intake was 70% as compared to baseline, while that of carbohydrate was 62%, protein 75%, and fat 83%.
|Figure 1: Percentage of energy and macronutrient intake after bariatric surgery|
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| Discussion|| |
The nutrient intakes of obese patients who had undergone metabolic surgery were assessed over 1 year. The study revealed that the participants had a significantly reduced intake of energy and macronutrients following metabolic surgery, which has been reported earlier. There was a decrease in comorbidities following metabolic surgery for all the participants, which could be attributed to the decline in body weight and body fat. These observations are in line with previous findings.
Mans et al. found the decrease in hunger and enhancement of satiety after SG, with prominent alterations in the physiology of gastrointestinal tract, these alterations include accelerated emptying of stomach, rise in postprandial cholecystokinin and glucagon-like peptide 1 levels and decrease in Ghrelin release, and he suggested that the combined effects of SG resulted in weight loss and improvement in glycemic control.
In our study, the energy intake was drastically and significantly reduced in the immediate postoperative period which is due to the enforced calorie restriction as a result of reduction in the size of the stomach after SG as well as in the DP. In view of small stomach size, patients were provided with liquid diet until the end of 1 month after metabolic surgery. After 1 month of liquid diet, there was a gradual replacement of semisolid diet followed by regular solid diet. Due to that the total energy intake was reduced significantly in the immediate postoperative period (until end of 1 month) and gradually increased at 6 and 12 months after surgery. However, the energy intake at 12 months is lower compared to preoperative energy intake. Energy restriction is a major determinant of postoperative weight loss and our findings support this. The decrease in energy intake following metabolic surgery could be due to lower orexigenic gut hormone levels, particularly the decrease in ghrelin levels., Ghrelin stimulates appetite and increases food intake and its secretion decreases after SG and, to some extent, in RYGB, which may contribute to the postoperative weight loss. In addition, alterations in gut microbiota have also been proposed as a cause of weight loss after metabolic surgery.
Studies from the western population report that calories obtained from macronutrients are 35–48% from carbohydrate, 15–23% from protein, and 37–42% from fat., It is estimated that for achieving 50% loss of excess weight 12 months after metabolic surgery, the optimal cutoff percentages for calories obtained from macronutrients are <49% carbohydrates, >24.5% protein, and <28% fat. However, in the present study, the macronutrient distribution at the end of 12 months was slightly higher for carbohydrate and lower for protein (53.5% carbohydrate, 15.8% protein, and 27.4% fat). Despite this, we observed a significant decrease in body weight and BMI at the end of 12 months.
The mean carbohydrate intake at baseline was low, which further decreased significantly after metabolic surgery. While similar results have been reported in the western population, in the Indian scenario where rice-based high carbohydrate diets are the norm, this is an interesting finding. However, we could not provide information on the type of carbohydrate consumed. Although there are no consensus guidelines on carbohydrate intakes following metabolic surgery, a daily intake of 130 g/day has been recommended. The applicability of these recommendations in the Indian context, however, is debatable, given the vast differences between the western and the cereal-based Indian diets. As consumption of simple carbohydrates is reported to cause dumping syndrome among patients who underwent metabolic surgery, it would be prudent to improve the carbohydrate quality by consumption of foods rich in dietary fiber and low glycemic index.
Body composition analysis showed a significant reduction in the MBF and SLM (skeletal muscle mass) at 6 and 12 months. The reduction in the MBF can be associated with the reduction in the carbohydrate and fat energy intake after the metabolic surgery. The reduction in the SLM can be related to the decrease in the protein energy intake after metabolic surgery. These parameters suggest that study individuals had taken lesser protein than the recommended levels, which resulted in significant muscle loss after metabolic surgery. There is a deviation in the protein intake which is less than the recommended levels and the reason for this deviation could be due to poor dietary complaints by the patients, it could be due to less frequent assessment of body composition and subsequent modification of diet bases on body composition and other results. Luigi et al. showed the lower decrease in fat-free mass in men after SG by supplementing with protein-enriched diet (protein intake 2.0 g/kg) without interfering with the kidney function.
As Indian diets tend to be higher in carbohydrate and lower in protein, it was not surprising that the protein intake of the participants was significantly lower than baseline both at 6 and 12 months (P < 0.001) after surgery, which was associated with a significant decrease in LBM. However, other authors have also reported lower protein intake among patients who have undergone metabolic surgery. In a systematic review, Ito et al. reported that low protein intake was associated with lower LBM among postmetabolic surgery patients. Preservation of LBM is reported to be beneficial in lowering the risk of postmetabolic surgery mortality and morbidity and protects against postmetabolic surgery weight gain. Thus, a protein intake of ≥60 g/day or ≥1 g/kg body weight/day would favor lean mass preservation.
The decrease in postoperative energy and macronutrient intakes could be a result of decreased food consumption due to intolerance or malabsorption. However, consumption of fat increased during 12 months postsurgery, which could be replaced by proteins in long term. Hence, there is a need to personalize dietary intervention based on the individual needs and concerns of the participants.
Therefore, strategies are needed to prevent the muscle loss after metabolic surgery. These strategies must include frequent body composition assessment, individualized diet to each patient, regular patient counseling to make the patient understand the importance of muscle mass and muscle loss after metabolic surgery, and periodical modification of the dietary recommendation based on the body composition assessment.
Although the dietary intake of calcium and iron was low, one could speculate that the prescribed vitamin and mineral supplement would be helpful in correcting postoperative nutritional deficiencies. This, however, was not reflected by a significant increase in serum iron or calcium levels. It is worth mentioning that the baseline levels of serum calcium and iron were low, which did not improve after metabolic surgery. Postoperative iron deficiency has been reported by other authors.,, It has been suggested that RYGB decreases calcium absorption by changing gastric physiology, effect of rapid weight loss, or by different pattern of meal consumption. Hence, increasing the dietary calcium may be helpful in facilitating absorption. Notably, a long-term follow-up study indicates that 25% of RYGB patients failed to take vitamin supplements; an online survey on 529 patients who underwent metabolic surgery also revealed that as much as 54% failed to take supplements regularly, which further highlights the need for appropriate dietary intervention.
Interestingly, there was a significant increase in serum Vitamin B12 and Vitamin D status after surgery in both the groups. Data are inconsistent regarding the postoperative micronutrient status of metabolic surgery patients. Coupaye et al. reported lower concentrations of Vitamin D and B12 among RYGB patients as compared to those who underwent SG. Another study reported low plasma levels of Vitamin D and B12 among patients who underwent metabolic surgery, irrespective of the type of surgery. The variations in the study design and the type and duration of supplements given could account for these differences.
Overall, the findings suggest that improving the dietary quality by including whole grains, fruits, and vegetables would be beneficial in improving the nutritional status and maintaining weight loss for metabolic surgery patients. Previous studies report that intake of whole grains, fruits, and vegetables was lower postmetabolic surgery. Therefore, it is advisable to consume a wholesome diet rich in protective foods, irrespective of the type of supplements consumed.
In conclusion, this study indicates that metabolic surgery results in a significant lowering of body weight and other comorbidities, which is concomitant with lower intakes of energy and carbohydrate. Our findings should be interpreted in view of certain limitations, the major one being the small sample size, due to which we could not differentiate between male and female participants. Secondly, the dietary intake was estimated using single 24-h recalls, which may not be representative of the habitual intake. Thirdly, we could not correlate the body composition changes with nutrient intake. However, the major strength of our study is that it provides valuable information on the dietary intake of obese patients who have undergone metabolic surgery. Furthermore, we have also followed up the dietary intake for a postoperative period of 1 year, which is representative of the period when most of the weight loss occurs. Finally, our findings highlight the importance of a multidisciplinary approach with proper follow-up and diet counseling during the postoperative period to ensure weight loss maintenance and avoid nutritional deficiencies. In addition, the need for individualized approach to address nutritional deficiencies is also emphasized. It has been reported that RYGB patients who received medical and nutrition therapy during the first year had significant excess weight loss and a reduction in BMI. Given the rising prevalence of obesity in India, metabolic surgeries may well become the preferred treatment option, especially for obese patients with comorbidities. Therefore, longitudinal studies on the nutritional status of patients who have undergone metabolic surgery would provide robust evidence to formulate guidelines to maintain weight and correct nutritional deficiencies.
This work is part of the PhD project of Dr. Sundaramoorthy Chandru undertaken at the University of Madras. We thank the participants for their cooperation.
Financial support and sponsorship
This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.
Conflicts of interest
The authors declare no conflict of interest.
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[Table 1], [Table 2], [Table 3]