Both high and low pre-infection glucose levels associated with increased risk for severe COVID-19: New insights from a population-based study.

Abstract

ImportancePatients with diabetes are known to be at increased risk for infections including severe coronavirus disease 2019 (COVID-19) but the relationship between COVID-19 severity and specific pre-infection glucose levels is not known.ObjectiveTo assess the differential effects of pre-infection glucose levels on the risk for severe COVID-19 amongst patients with and without diabetes.DesignPopulation based historical cohort study.SettingNational state-mandated HMO.PatientsAll adult patients with a positive SARS-COV2 test between March-October 2020.ExposureRecent fasting blood glucose (FBG) and glycated hemoglobin (HBA1C), age, gender, body mass index (BMI) and diagnoses of diabetes, hypertension, ischemic heart disease.OutcomeRisk for severe COVID-19, defined as resulting in ≥10 hospitalization days, ICU admission or death.Results37,121 patients with a positive SARS-COV2 test were identified; 707 defined as severe (1.9%). Unadjusted risk factors for severe disease were age (OR = 1.1 for every year increase; 95% CI 1.09-1.11, p Conclusions and relevanceElevated pre-infection blood glucose is a risk factor for severe COVID-19 even in non-diabetics. For patients with a diagnosis of diabetes both high as well as low pre-infection glucose levels are risk factors for severe COVID-19. Further research is required to assess whether these associations are causal, but we believe these findings can already have clinical implications for COVID-19 risk assessment and stratification.