Unvaccinated survivors of severe COVID saw rise in mental illness in year after, study suggests

In a JAMA author interview, study senior author Jonathan Sterne, PhD, of the University of Bristol, said, “The benefit of vaccination was that it prevented people from getting severe COVID-19 and therefore prevented the adverse consequences of COVID-19 in the longer term.”

The adjusted hazard ratios [HRs] for depression and serious mental illness in the first 4 weeks after COVID-19 diagnosis were 1.93 and 1.49 in the pre-vaccine cohort and 1.79 and 1.45 in the unvaccinated cohort, compared with 1.16 and 0.91 in vaccinated participants. 

The most common mental illness diagnosis was depression. A history of mental illness was a risk factor for mental illness after COVID-19. The incidence of depression in the first 4 weeks post-diagnosis and week 5 through 28 for serious mental illness in all periods was higher in participants aged 60 than in their younger counterparts. 

Rates of depression and serious mental illness were slightly higher for men than women in the first 4 weeks. The incidences of other mental illnesses were similar to those of depression and serious mental illness.

“Between-cohort differences in the incidence of mental illnesses in the absence of COVID-19 likely reflect both demographic differences and changes in diagnostic practices and access to health care during the pandemic,” the authors wrote.

The rise in mental illness was mainly seen after severe COVID-19 that led to hospitalization, with little elevation after milder illness. In the vaccinated group, the incidence of depression after mild or moderate COVID-19 was comparable to that before or without infection. Rates remained elevated after hospitalization.

Implications for public health, mental health services 

“The findings support recommendation of COVID-19 vaccination in the general population and particularly among those with mental illness, who may be at higher risk of both SARS-CoV-2 infection and adverse outcomes following COVID-19,” the researchers concluded.

In a university press release, first author Venexia Walker, PhD, of the University of Bristol, said, “Our findings have important implications for public health and mental health service provision, as serious mental illnesses are associated with more intensive healthcare needs and longer-term health and other adverse effects.”

Sterne said the research continues. “We have already identified associations of COVID-19 with cardiovascular disease, diabetes and now mental illnesses,” he said in the release. “We are continuing to explore the consequences of COVID-19 with ongoing projects looking at associations of COVID-19 with renal, autoimmune and neurodegenerative conditions.”