Background Neurocognitive dysfunction is the most common neurological complication seen in homozygous sickle cell disease (SCD) patients, and it appears to be associated with the severity of anaemia, indicating hypoxic brain injury as a causative factor, but the studies are limited to the paediatric population. Purpose We aimed to investigate the neurocognitive profile in adult homozygous SCD patients by subjective (Montreal Cognitive Assessment MoCA questionnaire) as well as objective (P300 event-related potentials ERPs) cognitive tests. Method Thirty adult homozygous SCD patients and 30 age-matched healthy controls were recruited. The MoCA questionnaire was employed for subjective cognitive status. ERP was recorded by using a modified 3-stimulus auditory oddball paradigm, which contains frequent, rare and novel stimuli. Amplitudes and latencies of corresponding original and difference ERP components were measured and analysed independently. Source analysis was done using sLORETA for P3a and P3b ERP components and compared between healthy controls and SCD patients. Results We found a significant reduction in total MoCA scores as well as their domains in SCD patients as compared to controls. For ERP, we found reduced amplitudes and increased latencies of P300 in SCD patients. This phenomenon was further validated in analysis of difference P3 components (P3dT i.e. target minus standard and P3dN i.e. novel minus standard). Additionally, we also found negative correlation between P3a/P3dN latency and attention domain of MoCA. Further, we found a diminished source activity for P3a and P3b in SCD as compared to control subjects. Conclusion These results indicate impaired neurocognitive abilities in cognitive domains of adult homozygous SCD patients like attention, executive functions and working memory, and reduced source activities of P300 components which may be due to chronic cerebral hypoxia in these patients.
Sahu et al. (2026) studied this question.