Cleveland Clinic, America conducted an observational study on 1223 patients with obesity and type 2 diabetes who had undergone bariatric or weight loss surgery matched to 5978 patients who had usual medical care suffering from the above stated diseases. Nearly 80% patients had hypertension, 74% had dyslipidemia (increased cholesterol and triglycerides) and 31% were taking insulin for diabetic control. Different statistical models in relation to the effects of weight loss were then used to identify the minimum weight loss needed to decrease the risk of death and of experiencing major adverse cardiovascular events like heart failure, coronary artery events, cerebrovascular events , atrial fibrillation and kidney disease.
The study revealed that 5-10% of surgically induced weight loss is associated with improved life expectancy and cardiovascular health. In comparison to about 20% weight loss is necessary to observe similar results with a non-surgical treatment. In addition this research also displays that metabolic surgery may contribute to health benefits that are independent of weight loss.
The study suggests that greater heart disease benefits are achieved with less weight loss post metabolic surgery than the medical weight loss using lifestyle interventions. Since the groundbreaking STAMPEDE Study was revealed, many additional studies have followed that have observed health benefits other than weight loss following metabolic surgery. This research too is a secondary analysis of a large study that showed weight loss surgery is associated with a 40% reduction in risk of death and heart complications in obese and type 2 diabetic patients.
There are continuous studies going on to understand the physiological changes in the surgically modified gastrointestinal tract, the impact on hormone secretion and the microbiome. Those beneficial changes may contribute to the cardiovascular and survival benefits of metabolic surgery, independent of weight loss. Therefore more work needs to be done in this field to understand the underlying mechanisms for the health benefits of metabolic surgery in patients with obesity and type 2 diabetes.