Introduction:

Obesity is a disease with a negative impact on survival; the prognosis of these patients is has controversial results. The term «obesity paradox» refers as a protective effect on mortality.

Objective:

To determine whether obesity is a protective factor in the critically ill patient.

Material y methods:

A cohort study was conducted. Data was obtained from ICU records of the ISSSTE Monterrey Regional Hospital during 2018, bivariate analysis was performed for χ2 and Mann Whitney’s U association, for Pearson’s formula correlation and survival analysis with Kaplan-Meier curve.

Results:

151 records of 73 obese and 78 non-obese patients were analyzed, it was observed that obesity is a protective factor for mortality (p = 0.044, OR 0.431(IC 0.187-0.992), BMI does not correlate with APACHE II (p = 0.066), however, an impact on the survival curve was observed (p = 0.42).

Conclusions:

According to the results obtained, it matches with the term «obesity paradox», however, its association with chronic degenerative diseases, prolonged stay in the ICU and its complications do not cease to have a negative impact on survival outside the unit.