Adults with long COVID face an increased risk of developing depressive and anxiety symptoms up to three years after their initial infection, according to a large population-based study published today in BMC Public Health.
For the study, researchers led by a team at the College of Health Sciences at the University of Missouri analyzed data from a population-based cohort of Michigan adults with confirmed SARS-CoV-2 infection from March 2020 to May 2022. The analysis excluded respondents who reported depressive or anxiety symptoms at baseline, allowing researchers to examine new-onset mental illness symptoms over time. Long COVID was defined as symptoms lasting 90 days or more after initial infection.
The researchers assessed symptoms 1.5 and three years after infection. By the three-year follow-up, 8.8% of respondents reported depressive symptoms, and 10.4% reported anxiety symptoms.
Symptoms emerged in distinct patterns
Adults with long COVID were substantially more likely to experience mental illness symptoms than those without persistent COVID symptoms. At three years, 16.9% of adults with long COVID reported depressive symptoms, compared with 7.5% of those without long COVID. Anxiety was reported by 17.2% of those with long COVID, versus 9.3% of those without. Overall, adults with long COVID had an 86% higher risk of depressive symptoms and a 60% higher risk of anxiety symptoms at three years.
Distinct symptom patterns emerged across the three-year follow-up period. Long COVID was most strongly associated with depressive symptoms emerging at the latter follow-up (adjusted risk ratio [aRRR], 2.64), while anxiety symptoms persisted across both follow-up periods (aRRR, 2.48).
“The different temporal patterns observed for depressive versus anxiety symptoms may suggest subtle distinctions in how Long COVID affects mental health over time,” write the authors. “The delayed association with depressive symptoms at the later follow-up may reflect cumulative effects of prolonged symptom burden, whereas the more persistent association with anxiety symptoms across both follow-ups may indicate a more immediate and sustained stress-related response.”
Need for mental health follow-up
The study has several limitations. Because the sample included only adults with confirmed infections, it may have excluded people who relied on at-home testing, had limited access to care, or were too ill to participate. Depressive and anxiety symptoms were measured with self-report screening rather than clinical diagnoses, and long COVID was defined based on participants’ reported recovery time, raising the possibility of misclassification.
Even so, the study’s prospective design and repeated follow-ups “strengthen the validity of our findings,” write the authors. They concluded, “Medical professionals should continue to follow up with individuals affected by Long COVID to monitor their mental health, and communities could consider implementing social support programs to promote psychological well-being among this population.”
