Does weight loss surgery improve heart health?

This study looked at the effects of weight loss surgery for patients with severe obesity and a previous heart attack. It found that patients who had the surgery had a lower risk of heart attack, heart failure, or death.

Heart health and obesity are closely connected. Obesity promotes the build-up of fatty plaque and hardening of the arteries, which increases the risk of heart attack and stroke. 

Weight loss (bariatric) surgery is an effective treatment for severe obesity. Roux-en-Y bypass involves forming the upper part of the stomach into a small pouch and connecting it directly to the small intestines. Weight loss surgery alters hunger and metabolism, leading to reduced body weight. One way this occurs is by increasing the amount of the GLP-1 hormone the gut releases after eating.

Some studies showed that weight loss surgery reduces the risk of a heart attack or stroke. However, other studies have found that people who are overweight and have had a heart attack have better outcomes than those of a typical weight with a heart attack. It is not clear whether bariatric surgery improves cardiovascular outcomes for patients with obesity and a previous heart attack.

This study used records from 509 patients with a previous heart attack who underwent bariatric surgery. For most patients, this was a laparoscopic (keyhole surgery) Roux-en-Y gastric bypass. Each patient was matched to a patient with similar age, sex, and bodyweight who also had a heart attack, but did not have bariatric surgery. They were followed for 4.6 years on average.

Surgery led to an average weight loss of 28% of body weight after 1 year. Patients who had weight loss surgery had a significantly lower risk of a cardiovascular event such as a heart attack in the following eight years (18.7% vs. 36.2%). Even after adjusting for other factors, patients undergoing surgery had a 56% lower risk of a heart attack or other cardiovascular event. Patients undergoing surgery also had a 55% overall lower risk of death.

This study found that bariatric surgery reduces the risk of a future cardiovascular event for people with obesity and a previous heart attack.

The group of patients undergoing surgery had lower risk factors in several areas, including previous heart failure (10% vs. 19%) and reduced ejection fraction, an indication of inadequate heart pumping (7% vs. 12%). This study was based on medical records. Some information might have been incomplete.