Effectiveness of bariatric surgery on body mass, biochemical parameters, and steatosis in metabolically healthy vs. unhealthy obesity​

Background:

The effects of bariatric surgery in metabolically healthy obese (MHO) versus metabolically unhealthy obese (MUO) patients are underexplored in the literature.

Aims:

The aim of the study was to compare the impact of bariatric surgery on weight loss, body composition, plasma biochemical parameters, and hepatic steatosis in MHO and MUO individuals.

Methods:

Preoperative and 1-year postoperative medical records of 82 men and women aged 18–65 years, with body mass index >30 kg/m₂, who underwent bariatric surgery from September 2021 to March 2023 were analyzed. MUO individuals were defined as those, metabolically unhealthy obese, with two metabolic syndrome risk factors, in preoperative data.

Results:

The prevalence of MHO and MUO individuals was 22 and 78%, respectively. Preoperative neck circumference and visceral adiposity index were higher in MUO individuals. Hepatic steatosis was the most common comorbidity in both groups. After 1 year, both groups demonstrated similar benefits from bariatric surgery in reducing body weight, adiposity, and anthropometric indices. Bariatric surgery also improved blood glucose, insulin sensitivity, and dyslipidemia in MUO individuals. However, 30% of MUO individuals presented with steatosis, compared to only 5.6% of MHO individuals. This outcome was accompanied by higher plasma levels of ferritin, alanine aminotransferase, and aspartate aminotransferase in MUO individuals.

Conclusions:

Bariatric surgery provided similar benefits in body mass for MHO and MUO individuals. However, after 1 year, MUO individuals still exhibited elevated markers of inflammation, liver injury, and steatosis, suggesting greater residual metabolic vulnerability.