The authors wrote that bariatric surgery - restrictive gastric banding and other forms of gastric bypass - can dramatically reduce the risk factors associated with stroke and heart disease risk. They added that the drop in risk comes about surprisingly quickly.
Studies have shown that for patients with severe diabetes type 2, bariatric surgery is far more effective than standard therapy.
Medications and diabetes or weight management treatments are far less effective and much slower, when compared to bariatric surgery.
2.6 million people in the USA die prematurely because they are obese, the authors explained. Excess body fat produces harmful chemicals that mess up the gut's hormonal balance, resulting in inflammation and insulin resistance - symptoms that mark the prelude to diabetes type 2.
The researchers gathered and examined data from studies dated between 1950 and 2012. They wanted to determine what the impact of bariatric surgery might be on heart failure, cardiovascular risk, and changes to the actual structure of the heart.
They eventually selected 73 studies to assess, involving nearly 20,000 individuals - all the studies looked at the effect bariatric surgery had on risk factors for stroke and heart disease.
Three-quarters of the study participants were female, and their average age was 42.
They found before surgery 44% of them had hypertension, 24% had diabetes, and 44% had dyslipidemia (high levels of harmful blood fats).
They were monitored for an average of 4.5 years post-surgery.
The patients lost an average of 54% of their excess weight; this varied from 16% to 87%.
4.5 years after their bariatric surgery, the researchers observed the following improvements in the patients' health:
- Hypertension - 63% of them either had significant improvements or the condition resolved completely
- Diabetes - 73% either had significant improvements or the condition was resolved. Researchers from the University of Massachusetts Medical Center reported in June 2102 that in their study 67% of patients who underwent gastric bypass surgery were in complete remission for diabetes type 2 after one year.
- Dyslipidemia - 65% either had considerable improvements or the condition was resolved
18 further studies revealed new benefits of bariatric surgeryThe researchers then identified 18 further studies with the same criteria - the impact of gastric bypass surgery on heart failure and structural changes to the heart. The studies involved 713 patients.
The following conditions were found to improve considerably after the operation:
- Left ventricular mass - the muscle tissue in the heart's main pumping chamber enlarges
- The E/A ratio - the proportion of blood the heart manages to push through in one beat
- Pump filling action - how well the heart relaxes after a contraction
The authors wrote:
"(bariatric surgery goes) beyond the realms of a cosmetic procedure and into the realms of interventions demonstrating efficacy in preventing cardiovascular events.
The magnitude of effect on [cardiovascular] risk factors is impressive, and to date no pharmacological therapy for weight management or diabetes has shown a comparable effect over these short time periods."
They explained that like any surgical procedure, bariatric surgery carries with it some risks. However, it not only reduces risk factors linked to stroke and heart disease, but also appears to improve overall heart health.
Gastric bypass surgery has the potential to save lives, they concluded.
Even obese family members of the patient who underwent bariatric surgery are much more likely to lose weight. A study from Stanford University School of Medicine reported in Archives of Surgery in October 2011 that obese household members of somebody who underwent gastric bypass surgery lost an average of ten kilograms (22 lbs) within 12 months of the operation.