Abstract
BACKGROUND: The neurological and psychiatric sequelae of coronavirus disease 2019 (COVID-19) have been documented, yet further data are needed to thoroughly evaluate the impact of COVID-19 on brain health years after the infection. AIM: To examine whether COVID-19 infection is associated with exacerbation, recurrence, or progression of pre-existing neurological or psychiatric disorders - a high-risk population that is underrepresented in COVID-19 outcome research in National Guard Health Affair patients in 4-years following a COVID-19 diagnosis. METHODS: For this multicenter retrospective cohort study, we used data from the National Guard hospitals electronic health records network (BestCare) with over 10 million patients. Our cohort comprised patients who had a COVID-19 diagnosis; a matched control cohort included patient did not expose to COVID-19 in same period. Age and sex were matching factors. We estimated the incidence of 14 neurological and psychiatric outcomes in nearly 4 years after a confirmed diagnosis of COVID-19. Using a multiple logistic regression, we compared incidences with those in propensity score-matched cohorts of patients with no exposure to COVID-19. RESULTS: Our primary cohort comprised 4437 patients diagnosed with COVID-19, and our propensity-score 1:1 matched control cohort comprised 4437 individuals. Nearly two-third of the COVID-19 cohort (71%) were diagnosed in 2020, and 2021. The most prevalent diagnoses for both cohorts were epilepsy 30.68%, mood disorder 23.92%, and nerve plexus disorder 22.13%. Dementia was nearly 4 times higher among COVID-19 cohort (8.27%) compared to the control cohort (2.57%). Five neurological and psychiatric outcomes had odds ratios (OR) that were significantly higher than 1 for people who had COVID-19 compared to people who had never been infected. These outcomes were cognitive deficit OR = 1.54, 95% confidence interval (CI): 1.23-1.91, P = 0.0001; nerve plexus disorder OR = 1.13, 95%CI: 1.01-1.25, P = 0.02; substance use disorder OR = 1.95, 95%CI: 1.12-3.38, P = 0.01; mood disorder OR = 1.16, 95%CI: 1.05-1.29, P = 0.003; and anxiety disorder OR = 1.39, 95%CI: 1.07-1.79, P = 0.01. CONCLUSION: The study highlights the persistent risk of neurological and psychiatric conditions in COVID-19 survivors up to four years post-infection. Although the incidence was lower than in previous large studies, long-term consequences remain significant, emphasizing the need for ongoing monitoring and support in mental health and neurological care.