Depression, Anxiety and Stress among Swedish University Students Before and During Six Months of the COVID-19 Pandemic: A Cohort Study.
Abstract The COVID-19 pandemic has a profound effect on societies and citizens worldwide, raising concerns about potential mental health impacts. We aimed to describe trajectories of depression, anxiety, and stress symptoms during the COVID-19 outbreak compared to before, and determine if trajectories were modified by pre-pandemic loneliness, poor sleep quality and mental health problems. We conducted a cohort study with 1836 Swedish university students entering before the onset of the pandemic, March 13, 2020, with follow-ups within three (FU1) and six months (FU2) of the outbreak. Generalized Estimating Equations were used to estimate mean differences in symptom levels over time-periods, and to estimate potential effect modifications. We found small differences in mean levels of the Depression, Anxiety and Stress Scale (DASS-21) over time. Compared to before the pandemic, depression increased by 0.25 points of 21 (95% CI: 0.04 to 0.45) at FU1 and decreased by -0.75/21 (95% CI: -0.97 to -0.53) at FU2. Anxiety decreased from baseline to FU1 by -0.09/21 (95% CI: -0.24 to 0.07) and by -0.77/21 (95% CI: -0.93 to -0.61) to FU2. Stress decreased from baseline to FU1 by -0.30/21 (95% CI: -0.52 to -0.09) and by -1.32/21 (95% CI: -1.55 to -1.09) to FU2. Students with pre-pandemic loneliness, poor sleep quality and pre-pandemic mental health problems did not show worse trajectories of mean mental health symptoms. In conclusion, symptom levels were relatively stable during the first three months of the pandemic, while there was a slight decrease during the summer months, probably due to seasonality effects.