Sex-based outcomes of obesity in critically ill patients: a retrospective cohort study.

Abstract

Background: Obesity is increasingly prevalent among critically ill patients, generally more common among females than males. Whether the patient's sex influences the outcome in these patients is unclear.

Objective: Evaluate the outcomes of critically ill-patients with obesity admitted to the intensive care unit (ICU).

Design: A retrospective cohort study.

Setting: ICU of King Abdulaziz Medical City, Riyadh, Saudi Arabia.

Patients and methods: All obese patients aged more than 18 years admitted to ICU between 2002 to 2017 were included.

Main outcome measures: The primary outcome was hospital mortality. Secondary outcomes included ICU mortality, ICU and hospital lengths of stay, mechanical ventilation duration, renal replacement therapy, vasopressor use, and tracheostomy. A multivariable analysis was conducted to evaluate the association of sex differences with hospital mortality.

Sample size: 7277 patients.

Results: Of the included patients with obesity, 3965 were females, and 3312 were males. The females were older, more likely to be admitted for medical reasons and less likely for trauma than males. The crude hospital mortality rate was significantly higher in females than males (1056 [26.7%] vs. 744 [22.5%], P<.0001). Multivariable analysis demonstrated no association between sex and hospital mortality (OR: 1.05, 95% CI: 0.94, 1.19, P=.52). However, age (OR: 1.04; 95% CI: 1.01-1.02; P<.0001), chronic liver disease (OR: 5.04; 95% CI: 4.19-6.06; P<.0001), and chronic renal disease (OR: 2.19; 95% CI: 1.86-2.57;P<.0001) were found to be associated with higher mortality while admission due to trauma showed lower mortality (OR: 0.69; 95% CI: 0.53-0.90; P=.007).

Conclusion: Obese females admitted to ICU have a higher hospital crude mortality rate than obese males. This difference does not appear to be related to sex, but rather to older age, higher comorbid conditions, and more frequent admissions related to non-trauma reasons among females.

Limitations: A single-center retrospective study.