Long-term Associations of COVID-19 Severity with Cognition and Mental Health in an Indian Cohort

Long-term cognitive outcomes following COVID-19 remain poorly characterized in South Asian populations. We assessed 181 Indian adults---99 with a reported history of COVID-19 at least six months earlier and 82 healthy controls---using standardized tests of working memory, selective attention, and pattern separation, alongside validated mental-health scales. Disease severity was assessed as per WHO guidelines rather than by degree-of-hospitalization, capturing individuals who experienced severe illness outside hospital care. Those with moderate-to-severe COVID-19 showed pronounced working-memory deficits compared with mildly infected and uninfected controls, while selective attention and pattern separation were comparable across groups. Vaccination at the time of infection was associated with better pattern separation, suggesting selective hippocampal protection. Notably, nearly all participants with moderate-to-severe illness reported a complete recovery despite continuing to exhibit measurable cognitive deficits. However, we did not observe any robust differences in affect or in the propensity toward depression and anxiety. Taken together, our findings suggest that hospitalization is an inadequate proxy for disease severity and that subjective recovery is not an appropriate yardstick for assessing Long COVID, underscoring the need for context-sensitive, population-based assessments of post-COVID sequelae.