Depressive Symptoms and Risk Factors During the COVID-19 Pandemic Among People with/Without Mental Disorders

<b>Background/Objectives</b>: The present study aimed to reveal the differences in changes in and risk factors for depressive symptoms between people with and without various psychiatric disorders during the pandemic. <b>Methods</b>: Longitudinal web-based surveys were conducted from 2020 to 2022. The diagnosis of mental disorders was based on self-reports by participants. Depressive symptoms were measured via the Patient Health Questionnaire-9 (PHQ-9), and coping was measured via the Brief Coping Orientation to Problems Experienced Inventory. A linear mixed model of PHQ-9, two-sample <i>t</i>-tests on Brief-COPE, and multiple linear regression for with and without mental disorders were conducted. <b>Results</b>: A total of 1443 participants were analyzed, of whom 9.3% had mental disorders. Depressive symptoms significantly decreased from January 2021 to January 2022, regardless of mental disorder status. Participants with mental disorders used certain coping styles more frequently than those without mental disorders. In a multiple linear regression analysis, no coping strategy was significantly effective for PHQ-9 scores among participants with mental disorders. However, being single was a risk factor, and emotional support use was associated with PHQ-9 scores. Additionally, behavioral disengagement was linked to PHQ-9 scores, regardless of mental disorder status. <b>Conclusions</b>: These results showed depressive symptoms might decrease in the long term regardless of the presence of mental disorders. Although there was no evidence of coping strategies effectively reducing depressive symptoms in people with mental disorders, the presence of a spousal relationship may play an important protective role for people with mental disorders and behavioral guidelines regardless of the presence of mental disorders.