Background: Obesity has long been considered a risk factor for individual morbidity and mortality for numerous cardiopulmonary diseases. However, multiple studies have shown that patients who are overweight or obese according to BMI have better inpatient outcomes.

Objective: To demonstrate the effect of obesity on outcomes of patients admitted for diabetes with and without complications.

Method: Data were extracted from the Nationwide Inpatient Sample (NIS) Database for 2016 and 2017. The numbers in the database are weighted to optimize national estimates. Hospitalizations involving all adults with a principal diagnosis of type 1 and type 2 DM were included. This group was further categorized based on the presence of obesity, defined as BMI >30, as a secondary diagnosis. The primary outcome was inpatient mortality and secondary outcomes were Length of stay (LOS) and Total hospital Charge (THC). Multivariate regression analysis was used to adjust for possible confounders.

Results: Around 1,031,009 hospitalizations had a principal diagnosis of DM types 1 and 2. This group had a prevalence of 15.67% of obesity as a secondary diagnosis. Inpatient mortality occurred in 6285 cases (0.61%). After accounting for age, sex, disease severity and type of diabetes, the adjusted odds ratio (aOR) for mortality in obese patients was 0.63 (95% CI: 0.526 - 0 .762, p< 0.001) compared to non-obese patients. Obese patients however, had adjusted increase in THC of $560 (95% CI: -347 - 1467, p=0.226) and adjusted increase in LOS of 0.3 days (95% CI: 0.3 - 0.4, p<0.001).

Conclusions: In patients hospitalized with a principal diagnosis of diabetes and its complications, obese patients had a statistically lower mortality rate. Hence, there seems to be growing evidence for the obesity paradox. More research needs to be done to determine the factors responsible for this recurrent phenomenon.


H. Shaka: None. M. Padilla Sorto: None. T.A. Gomez: None. E. Edigin: None. J. Xu: None. S.T. Yap: None.

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