Metabolic characteristics in patients with COVID-19 and no-COVID-19 interstitial pneumonia with mild-to-moderate symptoms and similar radiological severity

BACKGROUND AND AIMS: It is known that the highest COVID-19 mortality rates are among patients who develop severe COVID-19 pneumonia. However, despite the high sensitivity of chest CT scans for diagnosing COVID-19 in a screening population, the appearance of a chest CT is thought to have low diagnostic specificity. The aim of this retrospective case–control study is based on evaluation of clinical and radiological characteristics in patients with COVID-19 (n = 41) and no-COVID-19 interstitial pneumonia (n = 48) with mild-to-moderate symptoms. METHODS AND RESULTS: To this purpose we compared radiological, clinical, biochemical, inflammatory, and metabolic characteristics, as well as clinical outcomes, between the two groups. Notably, we found similar radiological severity of pneumonia, which we quantified using a disease score based on a high-resolution computed tomography scan (COVID-19 = 18.6 ± 14.5 vs n-COVID-19 = 23.2 ± 15.2, p = 0.289), and comparable biochemical and inflammatory characteristics. However, among patients without diabetes, we observed that COVID-19 patients had significantly higher levels of HbA1c than n-COVID-19 patients (COVID-19 = 41.5 ± 2.6 vs n-COVID-19 = 38.4 ± 5.1, p = 0.012). After adjusting for age, sex, and BMI, we found that HbA1c levels were significantly associated with the risk of COVID-19 pneumonia (odds ratio = 1.234 [95%CI = 1.051–1.449], p = 0.010). CONCLUSIONS: In this retrospective case–control study, we found similar radiological and clinical characteristics in patients with COVID-19 and n-COVID-19 pneumonia with mild-to-moderate symptoms. However, among patients without diabetes HbA1c levels were higher in COVID-19 patients than in no-COVID-19 individuals. Future studies should assess whether reducing transient hyperglycemia in individuals without overt diabetes may lower the risk of SARS-CoV-2 infection.