Patients with CLI and obesity experience significantly improved survival rates vs. patients without obesity

A study has highlighted juxtaposing trends in serious obesity-related cardiovascular events with critical limb ischemia (CLI), demonstrating lower mortality in patients with obesity by 50% vs. non-obese patients. The data were presented at the Society for Cardiovascular Angiography & Interventions (SCAI) 2025 Scientific Sessions.

Credit: Society for Cardiovascular Angiography & Interventions

“While obesity is a major risk factor for cardiovascular disease, it is also unfortunately tied to many factors that may be out of an individual’s control, like their socio-economic status, family history, or geographical location,” said SCAI President, James B Hermiller. “New research at SCAI’s 2025 Scientific Sessions aims to understand how obesity plays a role in the prevalence and progression of heart conditions, with the hope of improving early intervention tools and disease screenings for all patients with obesity.”

Since individuals with obesity and PAD have a significantly higher chance of developing CLI, three to five times more likely, the study aimed to uncover if the obesity paradox, the understanding that individuals with obesity may have better health outcomes than those with a normal weight, plays a role in clinical outcomes of CLI patients.

Investigators conducted a retrospective analysis of CLI patients using the National Inpatient Sample (NIS) Database from 2019-2022.  The data pool included 4,177,213 patients admitted for CLI. Of this pool, 59,030 (1.4%) patients were not living with obesity, with an average age of 59 years, and 1,142,519 (27.35%) patients were living with obesity, with an average age of 68 years.

The findings revealed that the obesity paradox does exist, the researchers claimed, as CLI patients with a higher body mass index (BMI) were associated with lower mortality and additional negative outcomes. The primary outcome of the research was in-hospital death, and data found that the patients without obesity group saw a higher death rate, almost twice as high (0.045 vs 0.023). This group also saw an increase in secondary outcomes in comparison to the obese group, which researchers selected as total hospital charges ($100,773 vs. $82,963), length of hospital stay (9.8 vs 7.8 days), endovascular repair (6.4% vs. 2.7%), surgical repair (1.8% vs 0.6%), major amputations (65% vs. 27%) and vascular complications (0.5% vs. 0.3%). However, there was no difference between groups for minor amputation.

“Our team was surprised to find obesity in CLI patients is linked to lower death rates along with shorter hospital stays, reduced hospital costs, fewer repairs, and lower instances of major amputation,” said Dr Albert Alexis Annan, Texas Health Harris Methodist Hospital Hurst Euless Bedford in Bedford, Texas and lead author of the study. “This data challenges the common perception that patients with obesity tend to have worse health outcomes, though we hope to emphasize the importance of seeking proper care and implementing appropriate and timely interventions regardless.”

The researchers said future studies to better understand the obesity paradox in CLI patients are warranted to improve decision-making in clinical settings.