The effect of Roux-en-Y gastric bypass in the treatment of hypertension and diabetes

Introduction: obesity has become a public health problem in Brazil and worldwide, due to its high prevalence. It is considered a risk factor for systemic arterial hypertension (SAH) and type 2 diabetes mellitus T2DM. Although lifestyle changes can control and even achieve complete T2DM remission, most patients have difficulty controlling blood glucose. Recent studies show that the Roux-en-Y gastric bypass (RYGB) is efficient for weight loss and control of T2DM and SAH in obese individuals. Objective: to analyze the effect of the RYGB technique on the control and treatment of comorbidities related to obesity. Method: this is a retrospective cohort study, with information obtained from the review of medical records, with data collection in the pre and postoperative period of patients undergoing bariatric surgery. We selected those with T2DM and SAH for the study. Results: 252 patients underwent RYGB in the service. Seventynine (31.3%) had T2DM and 64 had SAH associated with T2DM. Regarding T2DM and SAH, 37.9% and 43,7%, respectively, showed total remission of the disease after surgery. There was a reduction in the postoperative use of Metformin, insulin / Gliclazide, Propranolol, Losartan and Hydrochlorothiazide in 62%, 10.1%, 100%, 26.5% and 22.8% of patients, respectively. Conclusion: the RYGB technique is effective in the remission of T2DM and SAH. Even in cases where there was no total remission of the diseases, there was a significant drop in the use of medicines used for their treatment.


INTRODUCTION
T he increase in the prevalence of obesity has become a public health problem in Brazil and in the world 1,2 , mainly because it is a critical risk factor for metabolic diseases, such as dyslipidemia, Systemic Arterial Hypertension (SAH), and type-2 Diabetes Mellitus (T2DM). Although lifestyle changes, with weight loss induced by diet, exercise, and medical therapy can result in good control and even remission 3-5 of T2DM, most patients have difficulty in sustained control of their blood glucose 3 . The same happens with SAH, which has had weight loss as an initial treatment for a long time [6][7][8] , whose management is also challenging.
Bariatric surgery is the most efficient method for weight loss and for the control of comorbidities in obese patients. Current literature has shown that, in patients with T2DM, the remission rate varied between 24% and 95% in two years, depending on type of operation, definition of remission, and type of enrolled individuals 3,4,[9][10][11] . In patients with arterial hypertension associated with obesity, some studies have shown that bariatric surgery was responsible for a reduction in the use of antihypertensive medications and better control of blood pressure 4,10,12 . There is no doubt that surgery is a good therapeutic option for the control and treatment of comorbidities in obese patients. However, studies still lack regarding the class and quantity of medications used to obtain control of T2DM and SAH in the 1 ; andré Orsini ardenGh 1 ; Patrícia cOlOMbO-sOuza 2 ; PaulO Kassab, tcbc-sP 3 ; WilsOn rOdriGues Freitas-Jr, tcbc-sP 3 ; elias JirJOss ilias, tcbc-sP 3 .

Original article A B S T R A C T A B S T R A C T
Introduction: obesity has become a public health problem in Brazil and worldwide, due to its high prevalence. It is considered a risk factor for systemic arterial hypertension (SAH) and type 2 diabetes mellitus T2DM. Although lifestyle changes can control and even achieve complete T2DM remission, most patients have difficulty controlling blood glucose. Recent studies show that the Roux-en-Y gastric bypass (RYGB) is efficient for weight loss and control of T2DM and SAH in obese individuals. Objective: to analyze the effect of the RYGB technique on the control and treatment of comorbidities related to obesity. Method: this is a retrospective cohort study, with information obtained from the review of medical records, with data collection in the pre and postoperative period of patients undergoing bariatric surgery. We selected those with T2DM and SAH for the study. Results: 252 patients underwent RYGB in the service. Seventynine (31.3%) had T2DM and 64 had SAH associated with T2DM. Regarding T2DM and SAH, 37.9% and 43,7%, respectively, showed total remission of the disease after surgery. There was a reduction in the postoperative use of Metformin, insulin / Gliclazide, Propranolol, Losartan and Hydrochlorothiazide in 62%, 10.1%, 100%, 26.5% and 22.8% of patients, respectively. Conclusion: the RYGB technique is effective in the remission of T2DM and SAH. Even in cases where there was no total remission of the diseases, there was a significant drop in the use of medicines used for their treatment.  We recorded the number of medications used by each patient before and after the surgical procedure, to compare their need of use between both moments.
We determined the initial BMI on the day before the surgical procedure, and defined the final value after two years of follow-up.
The outcome of total T2DM remission was according to the ADA criteria 15 : Fasting Glucemia < 100 mg/dL and HbA1c < 6.0% without medication. Total

FOLLOW-UP
Patients were seen at the outpatient clinic three weeks after discharge from the procedure for clinical evaluation and decisions on further management with their respective attending physicians. All were reassessed monthly in the first quarter and then quarterly until the second year of follow-up. All patients included in the survey had at least six months of follow-up in the postoperative period before data collection and were followed for two years.

STATISTICAL ANALYSIS
We used the Mann-Whitney test to analyze the differences between the patients' ages and sex, the paired t test to verify changes in BMI before and after the surgical procedure, and the McNemar test to assess the presence of Diabetes and SAH before and after the operation. The level of significance was set at 0.05, or 5%.

RESULTS
During the study period, 252 patients underwent bariatric surgery at the service. Of these, 79 (31.3%) had type-2 diabetes, and 64 had associated systemic arterial

Marchetti
The effect of Roux-en-Y gastric bypass in the treatment of hypertension and diabetes When analyzing the BMI before and after the operation, we found a statistically significant reduction after the procedure (Table 3).
hypertension. Bariatric surgery was effective in reducing both T2DM and SAH.
The variables sex and age did not display significant statistical relevance in the resolution of T2DM and SAH (Table 1).      Even so, they observed that the proportion of patients without diabetes at five years was higher in the surgical group than in the drug-treatment-only group (50% versus 0%). The same was observed in multicenter studies that evaluated the remission of diabetes in patients undergoing different surgical procedures in the short and long term. RYGB led to remission of 83% in the short term 26 and 60.2% 27 in a seven-year period, becoming the best surgical modality for the treatment of T2DM.
A French case-control study included more than 30,000 patients in a six-year follow-up. Those who underwent bariatric surgery were more likely to discontinue (50% versus 9%), and less likely to start (1.4% versus 12%), antidiabetic medications compared with obese patients who were not operated 28  showing good pressure control in these patients. This way, we were able to observe that, in our series, RYGB influenced not only the total remission of T2DM and SAH, but also their partial control.
Our work has limitations that must be considered. As this is not a multicenter study, the sample size was limited by the number of patients seen at the services, so we decided not to perform a sample calculation. In addition, the duration of patients followup (two years) was relatively short, requiring an additional three-year follow-up to observe the real control of these comorbidities, the remission rate after a longer period, and the long-term effects of surgery. Given the morbidity of the procedure, our results do not imply that all patients with T2DM or SAH with characteristics similar to those included in our study should undergo bariatric surgery. However, we conclude that RYGB represents an additional option to help achieve control of these comorbidities by improving the metabolic and inflammatory profile of these patients.