Objectives:
To evaluate incidence of emotional and sleep disturbances (ESDs) in patients after hospitalization due to COVID-19, identify long-term predictors, and understand their influence on brain fog and quality of life at work (QWL).

Methods:
Patients of 18 or more years retrospectively reported ESDs (sadness, anxiety, restlessness, insomnia, excessive daytime sleepiness, nightmares), brain fog symptoms (BFS), QWL before COVID-19 and within 0–4, 4–12, and >12 weeks postinfection using paper or online validated questionnaire. Data regarding age, sex, comorbidities, pre-admission therapy, and laboratory results were collected. Finally, the study included 181 hospitalized individuals (mean age 56.02 ± 13.02 years; 37.02% women).

Results:
COVID-19 increased 1.6-fold to 2.2-fold incidence of ESDs within 0–4, 4–12, and >12 weeks post-infection (66.85%, 60.77%, and 50.28%, respectively). In the multivariable model, new-onset ESDs after COVID-19 were predicted by hemoglobin levels in the acute phase of infection (OR = 0.64; 95% CI: 0.50–0.80 per g/L; p = 0.001). In patients with pre-existing and new-onset ESDs, COVID-19 showed a 1.9-fold and 3.9-fold increase in BFS within >12 weeks post-infection, respectively. Deterioration in QWL >12 weeks post-COVID was associated with age (OR = 0.62; 95% CI: 0.37–0.73 per 10 years; p < 0.001), female sex (OR = 3.47; 95% CI: 1.40–8.56; p = 0.007), pre-existing (OR = 21.58; 95% CI: 2.57–181.30; p = 0.005) and new-onset ESDs (OR = 30.88; 95% CI: 3.85–247.90; p = 0.001).

Conclusions:
During follow-up, most patients with COVID-19 suffer from ESDs that are predicted by hemoglobin levels. The ESDs increase the risk of concomitant BFS. The ESDs, particularly sadness, restlessness, insomnia, and excessive daytime sleepiness, strongly affect QWL >12 weeks after COVID-19