Metabolic alterations and cognitive decline in long COVID

Abstract

Objective: To critically review the scientific literature on the association between cognitive dysfunction in patients with long COVID and the presence of metabolic disorders, particularly those related to the cardiometabolic profile. Methods: An integrative literature review was conducted using PubMed, SciELO, LILACS, and Latindex databases, covering the period from January 2021 to April 2025. Study selection followed predefined criteria based on the PICO framework. Results: Twenty-six studies were included. Symptoms such as brain fog, memory deficits, and executive dysfunction were recurrent and frequently associated with hyperglycemia, insulin resistance, and elevated body mass index. Findings from 18F-FDG PET scans revealed cerebral hypometabolism, most commonly in the frontal cortex (45%), temporal lobe (36%), and thalamus (27%). The presence of metabolic alterations worsened cognitive outcomes, especially in patients with pre-existing comorbidities such as type 2 diabetes and obesity. Final considerations: There is growing evidence that metabolic dysfunctions, including impaired glycemic control and mitochondrial dysfunction, contribute to neurocognitive deficits in long COVID. These findings underscore the importance of multidisciplinary approaches that include metabolic regulation and cognitive rehabilitation as key strategies for patient management.