Prevalence of Insomnia and Its Association with Depressive Symptoms Among Patients Recovered from COVID-19 After Hospitalization: A Cross-Sectional Study in Zanjan, Iran

Background: COVID-19 has been associated with persistent neuropsychiatric symptoms after recovery, including sleep disturbance and depressive symptoms. Patients who required hospitalization may be particularly vulnerable to post-acute psychological complications. This study aimed to determine the prevalence of insomnia and its association with depression among patients who had recovered from COVID-19 after hospitalization. Methods: This analytical cross-sectional study was conducted in 2023 at Shahid Beheshti Hospital, Zanjan, Iran. A total of 70 patients who had been hospitalized with PCR-confirmed COVID-19 and had recovered for at least 6 months were included. Data were collected from medical records and telephone interviews. Insomnia severity was assessed using the Insomnia Severity Index. Descriptive statistics, univariable and multivariable linear regression were used to analyze factors associated with insomnia severity. Results: The mean ISI score was 8.06 + 6.57. Overall, 40.0% of participants had at least subthreshold insomnia, and 17.1% had moderate to severe clinical insomnia. 30.0% of participants had some degree of depressive symptoms. In univariable analysis, higher depression score and lower educational level were associated with greater insomnia severity. In the multivariable regression model, depressive symptom severity remained independently associated with insomnia severity; each one-point increase in BDI-II score was associated with a 0.50-point increase in ISI score (adjusted {beta} = 0.50; 95% CI: 0.34-0.66; p < 0.001). Conclusion: Insomnia and depressive symptoms were common among patients who had recovered from COVID-19 after hospitalization. Depressive symptom severity was independently associated with greater insomnia severity. Routine screening for sleep disturbance and depressive symptoms may be beneficial in post-COVID follow-up care, particularly among previously hospitalized patients.