INTRODUCTION: Sleep is essential for preserving cognitive function and academic achievement. Medical students who face significant academic pressures and lifestyle disruptions are particularly susceptible to sleep deprivation. Although there is increasing awareness of this issue, longitudinal research investigating its effects on cognition and academic performance, especially among Indian populations, remains scarce.
OBJECTIVES: This study aimed to evaluate the longitudinal impact of sleep deprivation on cognitive performance and academic achievement among first-year Indian medical undergraduates while controlling for significant behavioral and psychological confounding variables.
METHODS: This longitudinal observational study, conducted over a period of three months, involved the enrollment of 80 first-year MBBS students (mean age of 19.1 ± 0.7 years), of whom 72 completed all assessments and were included in the final analysis. Sleep patterns were monitored daily using self-reported sleep logs. Cognitive function was assessed at baseline, six weeks, and 12 weeks using computerized tests for attention (Simple Reaction Time Test), working memory (Digit Span Test), and executive function (Stroop Test). Academic performance was evaluated based on internal assessments. Confounding variables, including screen time, stress, diet, and chronotype, were measured using validated instruments and accounted for in multivariable regression models. Statistical analyses were conducted using repeated measures analysis of variance (ANOVA), one-way ANOVA, Pearson correlations, and multivariable linear regression. All p-values refer to results from these tests unless otherwise noted.
RESULTS: A significant decline in sleep duration was observed over time (from 6.8 ± 0.9 to 5.9 ± 1.1 hours, p < 0.001), accompanied by progressive deterioration in cognitive scores: reaction time worsened (p < 0.001), digit span declined (p = 0.002), and Stroop interference increased (p < 0.001). Academic performance scores demonstrated a positive correlation with sleep duration (r = 0.43, p = 0.001). Multivariable models identified sleep duration as an independent predictor of academic performance (β = +2.78, p = 0.003) and cognitive domains, after adjusting for all confounders.
CONCLUSION: Chronic sleep deprivation among medical students results in significant cognitive decline and diminished academic performance. The findings highlight the significance of implementing institutional sleep hygiene programs to maintain cognitive function and enhance academic performance among medical students.
