Bidirectional relationship between depression and long COVID symptoms: findings from the Sulcovid-19 longitudinal survey

Long COVID is a condition that may manifest after SARS-CoV-2 infection, associated with complications such as depression and persistent symptoms. This study evaluated the relationship between prior depression and the occurrence of Long COVID, as well as investigated whether symptoms of this condition increase the risk of depression following infection in adults from southern Brazil. Using data from the longitudinal Sulcovid-19 study, the analysis included variables such as sex, age, skin color, marital status, income, smoking, body mass index, comorbidities, and hospitalization. The prevalence of Long COVID was 60 percentage points higher among individuals with prior depression, and this condition increased the probability of depression after infection by 65%. Associations were evaluated using Poisson regression in Stata 17.0. The results highlight the importance of investigating the implications of Long COVID and developing effective therapeutic approaches.