Impact of metabolic comorbidities on the clinical course of West Nile virus infection

Italy has experienced a marked increase in the incidence of human infections caused by West Nile virus (WNV). Metabolic and other comorbidities, particularly hyperglycemia, are associated with unfavorable outcomes in infectious diseases. This study aimed to investigate the association between metabolic comorbidities, with a specific focus on blood glucose (BG) levels at hospital admission, and the clinical course of WNV infection. 34 patients (22 males, 12 females, mean age 69 ± 14 years) with confirmed WNV infection were included. Clinical history, metabolic comorbidities, anthropometric and biochemical parameters at admission, and outcomes were collected. Arterial hypertension (35.3%), dyslipidemia (23.5%), and diabetes mellitus (8.8%) were highly represented metabolic comorbidities. 35.3% of patients had two comorbidities and 32.4% had three comorbidities, all of which included at least one of the metabolic comorbidities, while more than half had fasting BG levels ≥ 100 mg/dL or fasting BG levels > 125 mg/dL at admission. Duration of hospital stay increased significantly with BG category, with more days observed in patients with BG ≥ 100 mg/dL, whereas no significant differences were observed between Body Mass Index (BMI) groups. Correlation analyses showed a positive association of BG levels with days of hospitalization and Cerebrospinal fluid (CSF) glucose concentration. Patients who died had at least two comorbidities and BG levels > 125 mg/dL at admission. These results highlight the importance of BG levels at admission as a prognostic factor in WNV infection. Early recognition and management of elevated BG levels may be an important adjunct in the clinical care of affected patients.