An international study comparing long COVID patients across four countries found that people treated in the United States reported markedly higher rates of brain fog and mental health symptoms than patients in India, Nigeria, or Colombia.
Researchers say the gap is unlikely to be explained by biology alone and may instead reflect differences in culture, stigma, and access to diagnosis and follow-up care.
The analysis tracked more than 3 100 adults with persistent neurological symptoms after COVID-19 who were evaluated at academic medical centers in Chicago, Medellín, Lagos, and Jaipur.
Most participants were not hospitalized during their initial infection, allowing researchers to focus on long-term symptoms among people who experienced milder acute illness.
Brain fog reports varied sharply
Among non-hospitalized participants, 86% of U.S. patients reported brain fog, compared with 63% in Nigeria, 62% in Colombia, and 15% in India.
Patterns for depression and anxiety were similarly uneven, with nearly three-quarters of non-hospitalized U.S. patients reporting these symptoms, far above rates reported at other sites.
Investigators cautioned that higher reported symptom rates do not necessarily mean Americans have more severe disease.
They argue that patients in some settings may be less likely to label cognitive problems as a medical issue or may have fewer opportunities to be screened and treated.
Culture and healthcare access may matter
Senior author Dr. Igor Koralnik of Northwestern University said it is more culturally accepted in the U.S. and Colombia to discuss mental health and cognitive changes.
He added that stigma, health literacy, and limited availability of mental health providers could reduce reporting in other countries, masking the true burden.
Across all regions, commonly reported neurological complaints included fatigue, headache, dizziness, muscle pain, sleep problems, and sensory disturbances such as numbness or tingling.
The team said the findings underscore the need for culturally sensitive screening tools and more consistent long COVID follow-up, especially where care is harder to access.
The study was published in Frontiers in Human Neuroscience and adds to growing evidence that long COVID can disrupt daily function and work capacity long after infection.
Researchers involved in the project are also testing cognitive rehabilitation approaches for long COVID brain fog in partner sites, using shared protocols to compare outcomes.
Leave a Reply