Sleep, Learning, and Academic Achievement in Medical Students: A Systematic Review of Observational Studies

Abstract

Background: Sleep plays a fundamental role in cognitive functioning, memory consolidation, learning processes, and academic success. Medical students are particularly vulnerable to sleep disturbances due to demanding academic schedules, examination pressure, clinical responsibilities, and lifestyle factors. Although numerous observational studies have investigated the relationship between sleep and academic outcomes among medical students, the available evidence remains dispersed across different educational settings and geographical regions. Objective: To systematically review observational studies evaluating the association between sleep characteristics, learning outcomes, and academic achievement among medical students worldwide. Methods: A systematic review was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA 2020) guidelines. Electronic databases including PubMed, Scopus, Embase, Web of Science, and Google Scholar were searched from January 2000 to December 2025. Observational studies involving undergraduate or graduate medical students that assessed sleep parameters and reported learning or academic achievement outcomes were included. Data regarding study characteristics, sleep measures, academic outcomes, and associated factors were extracted and narratively synthesized. Results: A total of 38 observational studies involving approximately 27,600 medical students from 24 countries met the inclusion criteria. Poor sleep quality, insufficient sleep duration, and excessive daytime sleepiness were highly prevalent across studies. Thirty-three studies (86.8%) reported a significant association between adverse sleep characteristics and poorer academic outcomes. Students experiencing poor sleep quality or short sleep duration consistently demonstrated lower grade point averages (GPAs), reduced examination performance, impaired concentration, poorer memory retention, and decreased learning efficiency. Academic workload, examination stress, excessive smartphone use, social media engagement, and poor sleep hygiene emerged as major determinants of sleep disturbances. Conclusion: Observational evidence consistently demonstrates that inadequate sleep is associated with impaired learning and poorer academic achievement among medical students. Promoting healthy sleep behaviors may represent an important strategy for improving educational outcomes and student well-being.