In a sample of more than 400 older adults in Argentina who had recovered from COVID-19, more than 60% displayed some degree of cognitive impairment, a researcher from the University of Texas Health Science Center at San Antonio reported at the Alzheimer’s Association International Conference, according to a news release from the university.
It is not known whether the impairment, such as forgetfulness and language difficulty, will be progressive, said Gabriel de Erausquin, MD, PhD, Neurologist with Glenn Biggs Institute for Alzheimer’s and Neurodegenerative Diseases at the University of Texas Health Science Center at San Antonio. The individuals in the study are more than 60 years of age and have been assessed once so far. They will be followed for the next three to five years, de Erausquin said.
The study is being conducted by de Erausquin and collaborators from the Alzheimer’s Association-led global Cognitive Neuropsychiatric Sequelae of SARS-CoV-2 (CNS SC2) consortium.
Problems with thinking were seen even in recovered COVID-19 patients who had only a mild cold or respiratory ailment after virus exposure, de Erausquin said.
The study team also assessed participants for anosmia, loss of the sense of smell. The olfactory bulb, which contains the brain cells that react to smell, is primarily where the COVID-19 virus enters the nervous system, de Erausquin said.
Among the Argentine participants, 78% had recovered from a SARS-CoV-2 infection that was confirmed by polymerase chain reaction (PCR) testing. Testing confirmed that the other fourth of volunteers were never infected.
Of the 60% of recovered COVID-19 patients who had cognitive impairment, about one in three had severe cognitive impairment, de Erausquin said. This could be called “dementia-like syndrome,” because it looks like dementia but may not be persistent or progressive, he said.
People between the ages of 60 and 70 have about a 6% lifetime risk of developing Alzheimer’s disease. The Argentine study population reflects a rate of cognitive impairment that is 10 times higher.