The Impact of Diabetes and African American Race in COVID-19 Severity

Abstract Introduction: COVID-19, an illness caused by the novel coronavirus usually presents as a mild to moderate flu like illness, but can lead to pneumonia, acute respiratory distress syndrome and death in some patients. Since the onset of the COVID-19 pandemic there has been special attention towards patients with diabetes. Not only is diabetes highly prevalent in patients with COVID-19, but diabetes has been reported as a significant predictor of morbidity and mortality. Furthermore, race seems to be a predictor of severity with black people dying at 2.3 times the rate of white people. Methods: Here we performed a retrospective study of 524 cases of COVID-19 at an academic center in Chicago between March 2020 until August 2020. Data were obtained from patients that consented to the study to examine the relationship between diabetes, BMI, age, and race with degree of COVID-19 severity. Not all patients had all clinical and demographic data available. COVID-19 severity was determined using a severity index obtained from the measured SpO2 divided by the FiO2/fraction of inspired oxygen times 100. Numbers ≥ 315 mmHg were defined as low severity with patients generally requiring outpatient care, while 235–314 mm Hg were classified as moderate severity generally requiring inpatient care and≤ 234 mm Hg indicated high severity generally requiring intubation/ICU care. The Pearson correlation coefficient was used for linear correlation analyses. Proportion for categorical values were compared using the Chi squared test, the means for continuous variables were compared using two-tailed t tests or one way ANOVA (with Tukey post-test) for comparisons involving more than two conditions. A multiple linear regression model was used to assess the contribution of different variables. Differences were considered statistically significant at p<0.05 Results: Among 120 patients with an A1c, 55 (46%) patients had diabetes and 65 (54%) did not have diabetes. More patients with a high severity index were seen in the cohort with diabetes compared to those without diabetes (72% compared to 28% p=0.004). Univariate analyses revealed statistically significant positive correlations with higher COVID-19 severity and older age, BMI, and African American race. ANOVA analysis revealed a statistically significant difference between increasing BMI and worse severity category with a BMI mean of 29.3 kg/m2 in the low severity category compared to 34.9 kg/m2 in the moderate severity category (p=0.006). A multi-variate analysis adjusting for all variables revealed that A1c, older age and race were positively associated with higher COVID-19 severity. Conclusion: Increased A1c, older age and race are positively and independently associated with a higher COVID-19 severity index. Further research regarding the relationship between COVID-19 and these associations is urgently needed.