Body Mass Index As a Determinant of Clinical Outcomes in Disseminated Intravascular Coagulation: Observations from the National Inpatient Sample

Background:

Disseminated intravascular coagulation (DIC) is a catastrophic hypercoagulable state with micro and macrovascular obstruction leading to multi-organ damage. This widespread coagulation eventually leads to depletion of clotting factors and platelets, resulting in life threatening hemorrhage. Obesity has been studied as a hypercoagulable and hypo-fibrinolytic condition, owing to the higher plasma concentrations of clotting factors and impaired fibrinolytic activity with increased body mass index (BMI). The increased severity of DIC in obese patients with sepsis was demonstrated in the past using animal models. However, the association between obesity and outcomes of DIC is yet to be established. In this study, we tried to assess the impact of different subclasses of BMI on the outcomes of DIC hospitalizations.

Methods:

The National Inpatient Sample database (2016-2020) was queried, and International Classification of Diseases-10th-revision-codes were used to identify adults who were hospitalized with DIC. This population was stratified based on BMI to normal weight (BMI 18.5-24.9), overweight (BMI 25-29.9), mild obesity (BMI 30-34.9), moderate obesity (BMI 35-39.9) and morbid obesity (BMI 40 and above). The subcategory of normal weight was taken as reference. Categorical variables were compared using Chi-square test and continuous variables were compared using t-test. Multivariate regression analysis was performed to assess in-hospital mortality and other secondary outcomes of DIC in the different subcategories of BMI compared to normal weight patients, after adjusting for relevant confounders, various hospital and patient level characteristics.

Results:

299,305 DIC hospitalizations were identified, of which 31.72% were normal weight, 7.89% were overweight, 3.39% were mildly obese, 22.15% were moderately obese and 34.82% were morbidly obese. Mean age of DIC hospitalizations was found to be 57.92 years and 49.91% were females [p<0.001]. There were 61% whites, 18% blacks and 12% hispanics [p<0.001]. Mortality rate from univariate analysis was found to be 47.28% in normal weight, 40.55% in overweight, 43.75% in mild obese, 42.48% in moderately obese and 50.66% in morbidly obese DIC hospitalizations [p<0.001]. Multivariate regression analysis showed that patients with morbid obesity had a statistically significant increase in mortality compared to normal weight individuals [OR: 1.22, 95% CI: 1.10-1.36, p<0.001] whereas, overweight patients had a statistically significant lower odds of dying compared to normal weight [OR: 0.78, 95% CI: 0.65-0.92, p: 0.004]. There was no statistically significant association between mortality and mild/moderate obesity in DIC patients. Morbid obese patients were also found to have a statistically significant higher odds of developing circulatory shock [OR: 1.25, CI: 1.11-1.40, p<0.001], bleeding [OR: 1.34, 95% CI: 1.09-1.67, p: 0.007], acute respiratory distress syndrome (ARDS) [OR: 1.64, 95% CI: 1.25-2.26, p:0.001] and intubation with need for mechanical ventilation [OR: 1.27, 95% CI: 1.13-1.43, p<0.001], compared to normal weight patients. There was no statistically significant association found between these complications and overweight, mild obese and moderate obese patients. It was also found that odds of developing acute kidney injury was statistically significantly higher in all higher BMI categories as evidenced by overweight [OR: 1.34, 95% CI: 1.19-1.60, p:0.001], mild obese [OR: 1.39, 95% CI: 1.06-1.80, p: 0.014], moderate obese [OR: 1.38, 95% CI: 1.21-1.57, p<0.001] and morbid obese [OR: 2.37, 95% CI: 2.09-2.70, p<0.001], compared to normal weight patients.

Conclusion:

Our study shows that morbidly obese patients have worse mortality rate and various other in-hospital outcomes like circulatory shock, bleeding, ARDS and intubation when admitted for DIC. Overweight, mild and moderately obese categories also showed an increase in acute kidney injury when admitted with DIC. While obesity is already described as a risk factor for a multitude of disease processes, our study suggests a quantified risk for severe DIC in people with BMI above 40. However, further prospective studies are needed to fully understand the underlying mechanisms and to establish causation. These future investigations will be essential for validating our findings and guiding targeted prevention and treatment strategies.