Weight Maintenance After Surgery Could Help Heart Health

Surgical Weight Loss Patients Had Lower Mortality Rates Than Non-Surgical Patients

26th March 2025

Reporting From The Swedish Obese Subjects (SOS) Study

The Swedish obesity study is one of my favourite obesity studies. It has been running now for nearly forty years having started in 1987. The study has just over 4,000 individuals enrolled divided between 2,000 individuals with bariatric surgery and 2,000 matched controls.

In the latest publication, the researchers looked at those patients who had maintained their weight loss after surgery and compared them to those who had regained more than 20% of the weight that they lost in the first year after surgery. After 4 years of follow-up, they identified just over 700 individuals with weight regain compared to 630 who had maintained their weight. 

The weight regain group regained an average of 12.5 kg compared to the maintenance group who lost about 0.5kg . The BMI differences in the two groups remained largely the same over the following 20 years.

Many More Adverse Heart Events In Weight Regain Group Vs Weight Maintenance Group

Over that period, there were 245 events (heart attacks, strokes, and heart failure) in the regain group compared to 170 in the maintenance group, and this was a significant difference. However, the overall mortality rate was the same in the two groups. 

In both surgical groups, the patients who regained some weight and those who maintained their weight still had a lower overall mortality rate than the control group who had received non-surgical obesity care.

The main difference in mortality between the regain group and the maintenance group was cardiovascular disease. Cancer mortality between the two groups was similar. This is the first study to look at the differences in cardiovascular disease and mortality in those patients who regain weight as opposed to those patients who maintain their weight after bariatric surgery.

What Does This Mean For Surgical Weight Loss Patients?

I would encourage any patient who has had bariatric surgery, and has some weight regain, to contact the practice as there are benefits in maintaining weight loss. With the new weight loss medications available in recent years, that weight regain can often be treated medically without the need for further surgical intervention.

Yours sincerely,

Dr. Phil Lockie