Sleep quality, physical activity, and perceived academic performance of Italian adolescents

Background: Sleep disturbances are highly prevalent during adolescence and may negatively affect health and academic functioning. During the COVID-19 pandemic, changes in daily routines and lifestyle behaviors may have further impacted sleep patterns and physical activity levels in this population. Although associations between physical activity, sleep, and academic performance have been previously explored, evidence remains limited in specific sociocultural contexts, such as among Italian adolescents during the pandemic. The present study aimed to evaluate sleep quality using the Pittsburgh Sleep Quality Index (PSQI) and to examine its associations with self-perceived academic performance and weekly time dedicated to physical activity among Italian adolescents during the COVID-19 pandemic. Methods: This cross-sectional study was conducted between May and July 2020 with adolescent students (12-20 years) from public and private schools in the Lazio region, Italy, recruited through convenience sampling. Data were collected via a self-administered online questionnaire (Google Forms). Sleep quality was assessed using the Pittsburgh Sleep Quality Index (PSQI, Italian version). Physical activity and academic performance were evaluated through self-reported measures, including weekly activity duration (minutes/week) and perceived school performance. Descriptive statistics were calculated, and inferential analyses included chi-square or Fisher's exact tests, Pearson or Spearman correlations, and binary logistic regression models controlling for sex and age to estimate odds ratios (95% CI). Statistical significance was set at p < 0.05. The study was approved by an ethics committee. Results: A total of 437 adolescents (50.8% girls), with a mean age of 15.9 ± 1.37 years, were included. Based on the PSQI, 64.5% of participants presented poor sleep quality. Mean physical activity was 276.6 ± 217.6 min/week, and 67.9% were classified as physically active. Most adolescents reported good or excellent academic performance. Weekly physical activity time was negatively correlated with PSQI total score (r = -0.104; p = 0.04) and sleep latency (r = -0.102; p = 0.03). In the adjusted logistic regression model, physical activity was not significantly associated with sleep quality (OR 1.49; 95% CI 0.95-2.33; p = 0.079), while sex remained significantly associated. Conclusion: Italian adolescents presented a high prevalence of poor sleep quality during the COVID-19 pandemic. Although physical activity showed weak correlations with sleep parameters, it was not independently associated with sleep quality after adjustment. These findings highlight the importance of considering potential confounding factors when examining sleep-related behaviors in adolescents. Public policies that focus on sleep quality for adolescents are recommended, since it is possible to observe that several factors can affect adolescent sleep.