Prevalence and associated factors of depressive, anxiety, and stress symptom severity among high school students in the Mekong Delta of Vietnam

Depressive, anxiety, and stress symptoms are common among adolescents, yet many studies dichotomise Depression Anxiety Stress Scales-21 (DASS-21) outcomes, potentially losing information across severity levels. This study estimated symptom prevalence and examined factors associated with the severity of depressive, anxiety, and stress symptoms among Vietnamese high school students. A cross-sectional survey was conducted among all Grade 10–12 students at one school in the Mekong Delta, Vietnam. Bivariate and multivariable proportional-odds logistic regression models were fitted for three ordered severity categories: normal, mild/moderate, and severe/very severe. Analyses were performed in R version 4.6.0. Among 366 students, severe/very severe depressive, anxiety, and stress symptoms were reported by 13.4%, 27.9%, and 16.4% of students, respectively. Female sex was associated with greater severity of depressive (aOR = 2.18, 95% CI: 1.41–3.39), anxiety (aOR = 1.88, 95% CI: 1.24–2.86), and stress symptoms (aOR = 2.37, 95% CI: 1.54–3.68). Average/weak academic performance was associated with greater depressive symptom severity (aOR = 2.10, 95% CI: 1.11–4.04). Poor family relationships were associated with greater anxiety (aOR = 1.79, 95% CI: 1.11–2.90) and stress symptom severity (aOR = 2.10, 95% CI: 1.25–3.53), while parental academic expectations were associated with greater anxiety symptom severity (aOR = 1.66, 95% CI: 1.10–2.52). Grade 11 students had lower odds of greater stress symptom severity than Grade 10 students (aOR = 0.50, 95% CI: 0.31–0.80). Female sex, academic performance, family relationships, parental expectations, and grade level were differentially associated with symptom severity. Analyses that preserved the ordered structure of DASS-21 outcomes showed that associated factors differed across symptom domains. These findings support sex-sensitive screening and targeted school- and family-based mental health strategies.