An interesting article published by Hampshire and others in the EClinical Medicine on July 22nd 2021 explores this issue.
There is growing concern about possible cognitive consequences of COVID-19, with reports of long COVID symptoms persisting into the chronic phase and case studies revealing neurological problems in severely affected patients. However, there is little information regarding the nature and broader prevalence of cognitive problems post infection across the full spread of disease severity.
This study sought to confirm whether there was an association between cross-sectional cognitive performance data from 881,337 participants between January and December 2020.
The study undertook a clinically validated, web optimised assessment as part of the Great British Intelligence Test.
A questionnaire of items capturing self-report of suspected and confirmed COVID-19 infection and respiratory symptoms.
The study found that people who had recovered from COVID-19, including those no longer reporting symptoms, exhibited significant cognitive deficits versus controls when controlling for:
- Age
- Gender
- Education level
- Income
- Ratio economic group
- Pre-existing medical disorders
- Tiredness
- Depression and anxiety.
The deficits were of substantial effect size for people who had been hospitalised but also for non-hospitalised cases who had biological confirmation of COVID-19 infection.
Analysing markers of premorbid intelligence did not support these differences being present prior to infection. Finer grained analysis of performance across sub tests supported the hypothesis that COVID-19 has a multi domain impact on human cognition.
These results accorded with reports of long COVID cognitive symptoms that persist into the early chronic phase. There needs to be further research with longitudinal and neuroimaging cohorts to plot recovery, trajectories and identify the biological basis of cognitive deficits in SARS-CoV-2 survivors.
The deficits were most pronounced for paradigms that tapped cognitive function such as:
- Reasoning
- Problem solving
- Spatial planning
- Target protection
While sparing tests of simpler functions such as working memory span as well as emotional processing.
These results accord with reports of long COVID, where brain fog, trouble concentrating and difficulty finding the correct words were common.
Recovery from COVID-19 infection may be associated with particularly pronounced problems in aspects of higher cognitive or executive function. This observation accorded with preliminary reports of executive dysfunction in patients at hospital discharge, as well as previous studies of ventilated patients with acute respiratory distress syndrome pre-pandemic.
It was noted, however, that when the analysis of individual test scores was constrained to people who had positive biological tests, the profile in mild and non-hospitalised cases extended to spatial span.
The London General Practice, the leading London doctors’ clinic in Harley Street, offers a full multidisciplinary support service for all those suffering with long COVID.
It has brought together experts in their fields to help manage all those with any symptoms of any kind.
Please do not hesitate to get in touch if you have any concern.
Dr Paul Ettlinger
BM, DRCOG, FRCGP, FRIPH, DOccMed