Exploring the Role of Insulin Resistance in Fueling Stroke Vulnerability and Worsening Post-stroke Prognosis: A Narrative Review of Current Literature

Stroke remains one of the world's greatest causes of disability and death. Insulin resistance (IR) impairs insulin's beneficial effects on the brain and can change the course of illness in post-stroke patients. This review aims to find sufficient evidence to support the causal association of IR in ischemic stroke and with post-stroke prognosis (PSP). The review will also list probable mechanisms to better understand how IR affects stroke pathology. Various articles from PubMed Central, MEDLINE, and PubMed databases were reviewed, and then after careful consideration, 17 articles were selected. The studies, using various genetic and metabolic markers, have linked IR to increased incidence of ischemic stroke. Among the various types of strokes investigated from this standpoint, silent lacunar infarct stands out as a widely researched subtype. Even though the exact pathogenesis is still unclear, current evidence shows an interplay of atherosclerosis, embolism, and platelet dysfunction. The development of early neurological decline (END) in post-stroke patients has been used to link IR to poor PSP. It is also acknowledged to have contributed in some way to poor three-month outcomes. Modifying inflammatory pathways and developing glucotoxicity are some of the pathways by which IR affects PSP. After reviewing the studies, significant evidence was found to support the role of IR in causing ischemic stroke as well as in poor PSP. Additional investigation is required to assess its influence on three-month prognosis and its significance in various stroke subcategories.