Impact of body mass index on 90-day survival in patients in cardiogenic shock treated with V-A ECMO: A propensity weighted analysis.

OBJECTIVE

The impact of body mass index (BMI) on outcomes in refractory cardiogenic shock requiring extracorporeal membrane oxygenation (ECMO) is not well understood. We aimed to assess: (i) whether BMI is independently associated with outcomes, and (ii) whether patients with obesity (BMI > 30 kg/m2) have worse outcomes than lean counterparts.

METHODS

We conducted a retrospective analysis of a prospectively maintained database from two French ECMO centers (2006-2022). The impact of BMI was evaluated using inverse propensity-score weighted (IPSW), propensity-score (PS) matching, and multivariable (MV) models, adjusting for predefined confounders. The primary outcome was 90-day mortality. The relationship between BMI and outcomes was examined using generalized additive models. Outcomes were compared across three BMI categories (<25 kg/m2, 25-30 kg/m2, and > 30 kg/m2). Patients treated with extracorporeal cardiopulmonary resuscitation (E-CPR) were analyzed separately.

RESULTS

Among 921 patients, BMI was not significantly associated with 90-day mortality (HR 0.99, 95 % CI 0.97-1.01, p = 0.2), despite more ECMO-related complications. This was consistent across PS-matched, IPSW, and MV models. No significant non-linear relationship between BMI and 90-day mortality was found. Among the 204 patients with ECMO during cardiopulmonary resuscitation, those with BMI < or ≥ 30 kg/m2 had 90-day mortality rates of 76 % and 71 %, respectively (p = 0.5).

CONCLUSION

Patients with obesity treated with ECMO for refractory cardiogenic shock have similar 90-day outcomes to their lean counterparts, despite higher respiratory, renal, and device-related complications.