# Effect of body mass index on mortality for diabetic patients with aortic stenosis

## TL;DR

This study finds that being underweight increases mortality risk while obesity reduces it for diabetic patients with aortic stenosis.

## Contribution

The study provides new evidence on how BMI affects mortality in diabetic patients with aortic stenosis.

## Key findings

- Underweight diabetic patients with AS had higher all-cause mortality compared to normal weight individuals.
- Obese patients had lower all-cause and cardiovascular mortality than normal weight patients.
- Underweight patients faced higher non-cardiovascular mortality risks.

## Abstract

Background: Several studies suggest an “obesity paradox,” associating obesity with better cardiovascular outcomes in patients with type 2 diabetes mellitus (DM) or aortic stenosis (AS) compared to normal or underweight individuals. This study explores the impact of body mass index (BMI) on diabetic patients with AS.

Methods: Between 2014 and 2019, patients with DM who underwent echocardiography were analyzed. Outcomes included all-cause mortality, cardiovascular, and non-cardiovascular death. Patients were categorized as underweight, normal weight, or obese based on BMI (<18.5, 18.5 to 27, and >27 kg/m2, respectively).

Results: Among 74,835 DM patients, 734 had AS. Normal weight comprised 65.5% (n=481), underweight 4.1% (N=30), and 30.4% were obese. Over a 6-year follow-up, underweight patients had significantly higher all-cause mortality (HR 1.96, 95% CI 1.22 – 3.14, p = 0.005), while obese patients had significantly lower mortality (HR 0.79, 95% CI 0.68 - 0.91, p=0.001) compared to the normal group. Regarding etiologies, underweight patients had a higher risk of non-cardiovascular death (HR 2.47, 95% CI 1.44-4.25, p = 0.001), while obese patients had a lower risk of cardiovascular death (HR 0.66, 95% CI 0.50-0.86, p=0.003). Subgroup analysis showed a consistent trend without significant interaction.

Conclusions: BMI significantly impacts mortality in DM patients with AS. Being underweight is associated with worse non-cardiovascular death, while obesity is linked to improved cardiovascular death outcomes.