Vaccination against SARS-CoV-2 contributed to reducing the prevalence of depression in Chinese adults - A cross-sectional study

SARS-CoV-2 vaccination has been reported to improve mental health. However, few relevant data were collected in China. The study aimed to evaluate the impact of SARS-CoV-2 vaccination on the risk of depression in China and risk factors contributing to depression. This is a cross-sectional study carried out from May 2020 to July 2021. Participants were widely recruited in China to participate in the survey using an online questionnaire including Patient Health Questionnaire-9, Generalized Anxiety Disorder-7, Athens Insomnia Scale-8.After exclusion of 105 ineligible questionnaires, 9452 participants were included in our final analysis. Chi-square test and Multivariable logistic regression analysis were used to analyze data. Of the 9452 participants, 7207 were vaccinated. Our results showed that the prevalence of depression decreased significantly after vaccination (56.1 % for unvaccinated participants vs. 19.7 % for vaccinated participants). The prevalence of mild, moderate and severe depression was also significantly lower in the vaccinated participants than in the unvaccinated participants (14.8 % vs 29.0 %, 2.8 % vs 13.3 %, 2.0 % vs 13.8 %, respectively). Besides, among vaccinated participants, male and aged participants had a lower chance of developing depression (AOR = 1.34; AOR = 0.63; AOR = 0.5, respectively). In addition, although with vaccination, participants with anxiety and insomnia were more likely to suffer from depression (AOR = 29.2; AOR = 11.89). The study was a cross-sectional survey. The numbers of participants differed much in the two groups. The present study confirmed that SARS-CoV-2 vaccination contributed to reducing the prevalence of depression in Chinese adults. Moreover, vaccinated men and older adult participants had less prevalence of depression.