Post-COVID Neurocognitive Disorder and Its Relation with Interleukin: A Hospital-based Cross-sectional Study

Background: The aim of this study was to determine the relationship between post-COVID neurocognitive symptoms and interleukin-6 levels.

Methods: This was a hospital-based cross-sectional study wherein patients complaining of forgetfulness post-infection with coronavirus disease-2019 (COVID-19) were taken up for study (n = 53) from February 2023 to June 2023. The forgetfulness was characterized using the memory subscale of Postgraduate Institute-Battery of Brain Dysfunction (PGI-BBD). In addition, sociodemographic data were collected from patients. After obtaining written informed consent, 3 mL of peripheral venous blood was collected from patients, and interleukin-6 levels were measured. Other inflammatory markers, like C-reactive protein (CRP), were also measured.

Results: The mean age of participants was 46.11 ± 8.58 years. Twenty-nine (54.72%) respondents were female, and 24 (45.28%) were male. Most (62.2%) of the patients in the study suffered from mild-to-moderate severity of COVID-19 infection. Among these patients, 43.3% had impairment in recent memory, 32 patients (60.3%) had impairment in attention and concentration, 54.7% had impairment in delayed recall, and 33.9% had impairment in immediate recall. Impairment in delayed recall was associated with a raised level of interleukin-6 (P = .0048 [P < .05]).

Conclusion: Patients with impaired recall on PGI-BBD post-infection with COVID-19 have raised levels of interleukin-6, suggesting the role of neuroinflammation in post-COVID neurocognitive symptoms. Interleukin-6 is a marker of neuroinflammation that has been linked to cognitive decline in various studies. It can be used to predict cognitive decline and also aid in diagnosis.