Associations Between Mental Health and Academic Performance in High School Students: A Cross-Sectional Study in Southernmost Brazil

INTRODUCTION: Psychiatric symptoms are prevalent among teenagers and consistently associated with impaired academic performance. OBJECTIVE: This study aimed to examine the relationship between symptoms of depression, anxiety, and stress and academic performance among high school students in southern Brazil. METHODS: This cross-sectional study (2022) involved students from the Federal Institute of Rio Grande do Sul (IFRS), Brazil. Mental health was assessed using the Depression, Anxiety, and Stress Scale (DASS-21), and academic performance was estimated based on the average grades taken in the academic year. Data were analyzed using STATA 15.1 with Poisson regression for prevalence ratios. RESULTS: Among 480 eligible students, 391 had complete data (response rate: 81.5%). The mean age was 17.0 years (SD = 1.5); 56% were male, 46% first-year students, 33% physically inactive, 5% smokers, 36% reported alcohol consumption, and 32% had good or very good sleep quality. The mean DASS-21 score was 15.2 (95%CI 14.4-16.5). Severe or very severe symptoms were observed in 16.2% for depression, 15.3% for anxiety, and 9.1% for stress, with 22.3% presenting at least one severe outcome. The mean academic grade was 7.8 (SD = 1.4); 21% scored <7.0 and 17% ≥9.0. Higher mental health scores were associated with lower and reduced higher academic performance. Depression and stress, but not anxiety, were associated with poorer performance; only depression showed an inverse association with high performance. CONCLUSION: This study demonstrated a negative association between depressive and stress symptoms and academic performance in high school students, while anxiety symptoms were not significantly associated.