GAstric Bypass to Treat obEse Patients With steAdy hYpertension

Randomization:

The randomization list is electronically generated through specific software. A block randomization is conducted with varying block sizes at the rate of 1:1. Confidentiality of the randomization list is ensured by the central automated randomization system, through the Internet, available 24 hours a day (ACT Clinic - Sistema de Estudos Clínicos do IEP HCor).

Blinding Scheme:

Because the study involves a surgical procedure, investigators and patients cannot be blind for treatment allocated to patients.

Roux-en-Y Gastroplasty Patients allocated to surgical treatment will be admitted to the hospital to be subjected to a Roux-en-Y gastric bypass with a biliopancreatic loop of 100cm and a alimentary limb of 150cm.

Antihypertensive Treatment:

The treatment of hypertension will be standardized for all study patients. Prescribed drugs will include preferably a renin-angiotensin blocking system drug and a calcium channels blocker, except if these are contraindicated or the patient has achieved good blood pressure control using other drugs prior to study recruitment. Other drugs can be added at discretion of the attending investigator to achieve a target blood pressure of 130 x 80 mmHg. Patients are treated individually for the other associated comorbidities. Obesity treatment in the control group includes dietary advice, motivation for the practice of physical activities, and drug treatments for diabetes and dyslipidemias if applicable.

Laboratory tests and other exams:

All patients will be subjected to the following measurements throughout the study:

• Outpatient Blood Pressure Monitoring (ABPM)
• Blood pressure measurements taken in doctors' offices:
• Central pressure and associated measurements (SphygmoCor®)
• Polysomnography
• Anthropometry
• Nutritional survey
• Laboratory tests
• Echocardiogram
• Electrocardiogram
• Abdominal ultrasound
• Upper gastrointestinal endoscopy with H.pylori testing

Inclusion criteria

• Adults aged between 18 and 65 years old.
• hypertension diagnosis defined as in use of at least 2 high blood pressure medication at full doses.
• body mass index between 30,0 and 39,9 kg/m2.

Exclusion criteria

• hypertension ≥ 180/120 mmHg;
• cerebrovascular diseases in the last 6 months.
• Cardiovascular diseases (myocardial infarction, angina, cardiac failure) in the last 6 months.
• Baseline psychiatric disorders: schizophrenia, bipolar disorder, severe depression, psychosis.
• Renal diseases: diabetic nephropathy, creatinine clearance < 30 ml/min.
• Patients with secondary hypertension except due to the sleep apnea.
• Advanced peripheral arterial disease
• atrophic gastritis
• Diabetes mellitus type 1 and type 2 with HbA1 c >7,0%
• alcoholism or use of illicit drugs
• smokers
• previous laparotomy
• severe hepatic disorders
• Pregnancy or women not using effective contraceptive methods.
• Recent neoplasm (< 5 years)
• Immunosuppressant drugs
• Unable to understanding and follow the study protocol orientations.