Impact of dengue fever on depression, anxiety, and stress symptoms in Esmeraldas Province, Ecuador: a prospective cohort study

Background Physical symptoms of dengue have been documented extensively, but knowledge gaps on dengue-associated mental health hazards remain. We investigated the frequency of psychiatric symptoms (depression, anxiety, and stress) and neurocognitive performance during the first year after a dengue episode. Methods Using DASS-21 scores at 3, 6, and 12 months, we assessed depression, anxiety, and stress in anti-dengue IgM-positive adults and matched controls during the 2021 dengue season in Esmeraldas Province, Ecuador. Patients with DASS-21 scores <= 4 were considered normal; those with scores of 5-7, 8-10, and >= 11 indicated mild, moderate, and severe depression, respectively; cutoff scores for anxiety and stress were >= 5 and >= 9, respectively. We also assessed 'delayed matching to sample' (DMS) and 'spatial working memory' (SWM) using the Cambridge Neuropsychological Test Automated Battery. Results We enrolled 102 cases and 78 controls. At 3 months, 90 cases and 70 controls were available for follow-up, among these 40/90 (44.4%) cases and 12/70 (17.1%) controls had DASS-21 scores >= 5 (RR 2.7, 95% CI [1.5-4.7]). Dengue remained a predictor for depression after adjusting for age, sex, and COVID-19 status. We observed no difference in anxiety between the groups, but stress scores increased at month 3 (RR 1.87, 95% CI [1.01-3.4]). DASS-21 scores normalized during follow-up. DMS and SWM did not differ between groups at 3 and 6 months. At month 12, cases had lower SWM than controls did (p value < 0.001). Conclusions Care providers should be aware of dengue-associated mood disorders and facilitate timely referral to mental health services. Future longitudinal studies are warranted to validate our observations regarding the impact of dengue on mental health and neurocognitive status in affected patients.