Patients with the most severe taste and smell disorders after coronavirus had the worst results in cognitive tests, especially when they involved memory
A study published in the scientific journal ‘European Archives of Psychiatry and Clinical Neuroscience’ found a link between loss of smell or taste After passing covid-19 memory problems,
Studies done before the Kovid-19 pandemic Discovered that lack of smell may be an early sign of impending presence of disease Alzheimer’s,
There is evidence in the scientific literature that this sensory disorder may first appear years before cognitive symptoms, suggesting that a link between brain regions Responsible for memory and interpretation of olfactory stimuli.
In this new work, a group of Brazilian researchers analyzed clinical data from 701 patients treated for moderate or severe COVID-19 at the Hospital das Clinic between March and August 2020.
worst result
Evaluation done six months after being discharged from hospital showed that patients with most severe taste and smell disorders after Covid-19 poor results in cognitive tests Particularly when these involved memory, and that the test results were not related to the severity of their condition in the acute phase of the disease.
“Smell is an important link to the outside world and is closely related to past experiences. For example, the smell of cake may evoke memories of grandma. In terms of brain connections, smell is more strongly associated with memory than with vision. contacts and hearing”, confirms otorhinolaryngologist Fábio Pinna, the last author of the article collecting the study.
The median hospital stay for the entire group of patients studied was 17.6 days. Their average age was 55.3 years. More than half (52.4%) were male. A slightly higher proportion (56.4%) required intensive care for disease complications, and just one third (37.4%) were intubated.
For this type of study smell and taste were first assessed six months after hospital discharge using standardized questionnaires, which also included aspects related to quality of life.
Moderate or severe taste deficit (loss of sense of taste) was the most common sensory complication (20%) This is followed by moderate or severe olfactory deficit (18%), a moderate or severe deficit in both smell and taste (11%), and parosmia (9%), which is a distortion of olfactory perception so that a previously pleasurable odor is for example unpleasant. it happens.
Of the participants, 12 reported having olfactory hallucinations (perceiving odors unknown to others) and nine taste-related hallucinations (experiencing a taste without having eaten something). in both cases, Most said the hallucinations only happened after suffering from Covid-19. In response to a question about their general health status, 10.1 percent chose poor or very poor, 38.5 percent chose fair, and 51.4 percent chose good or very good.
psychotic symptoms such as anxiety And this depression, Neuropsychological tests were also implemented, through standardized questionnaires, and to measure cognitive functions such as memory, attention, and reasoning speed.
Finally, statistical techniques were used to analyze all results to explore the association between neuropsychiatric symptoms and sensory dysfunction.
it was found that Subjects reporting parosmia had more memory problems than the rest, whereas those with moderate or severe taste deficits performed significantly worse on a test used to assess episodic memory and attention. Those who reported moderate or severe loss of both smell and taste were also found to have significantly impaired episodic memory.
“We didn’t find any psychotic symptoms [como la ansiedad o la depresión] This was associated with loss of smell and taste, but as expected, we observed that patients with greater chemosensitivity changes had more impaired attention and contextual memory. This finding confirms the hypothesis that COVID affects cognition, and that damage to the region has not only psychosocial or environmental causes”, details the article’s first author, Rodolfo Damiano.