Impact of Depressed Mood as a Risk Factor on COVID-19 Disease Severity

Background and Objective: The results of many studies have shown that depression can cause weakened cellular immune control, decreased antibody response to some vaccines, and the development and exacerbation of numerous medical disorders, including viral disease. This study aimed to investigate the relationship between the severity of COVID-19 disease and depression. Materials and Methods: In this cross-sectional multicenter study, conducted between February 2021 and March 2021, patients were randomly selected at the time of positive results of reverse transcription polymerase chain reaction for COVID-19, and called to assess for a history of depression within the previous two weeks using the Patient Health Questionnaire (PHQ-9). Afterward, 14 days later, they were asked about the COVID-19 infection course. Results: The number of days a patient had a fever, decreased sense of smell or taste, and other symptoms were higher in depressed than in non-depressed individuals (P<0.05). Patients with COVID-19 symptoms (fever and decreased smell or taste) and consequences (hospitalized and intubated) had higher PHQ-9 scores than patients without these symptoms (P<0.05). Moreover, 46.2% of depressed and 18.5% of non-depressed patients reported complications of the disease (including renal, gastrointestinal, vascular, neurological, and skin complications), which was statistically significant (p-value exact test:0.026). Conclusions: There was a significant relationship between depression and the duration and severity of COVID-19. This preliminary study suggested that baseline depression had adverse effects on the seriousness of COVID-19 disease. More studies with substantial evidence are needed to confirm the causality effect