Physical Function and Association with Cognitive Function in Patients in a Post-COVID-19 Clinic—A Cross-Sectional Study

Abstract

Patients with long-term health sequelae of COVID-19 (post-COVID-19 condition) experience both physical and cognitive manifestations. However, there is still uncertainty about the prevalence of physical impairment in these patients and whether there is a link between physical and cognitive function. The aim was to assess the prevalence of physical impairment and investigate the association with cognition in patients assessed in a post-COVID-19 clinic. In this cross-sectional study, patients referred to an outpatient clinic ≥ 3 months after acute infection underwent screening of their physical and cognitive function as part of a comprehensive multidisciplinary assessment. Physical function was assessed with the 6-Minute Walk Test, the 30 s Sit-to-Stand Test and by measuring handgrip strength. Cognitive function was assessed with the Screen for Cognitive Impairment in Psychiatry and the Trail Making Test-Part B. Physical impairment was tested by comparing the patients’ performance to normative and expected values. Association with cognition was investigated using correlation analyses and the possible explanatory variables regarding physical function were assessed using regression analyses. In total, we included 292 patients, the mean age was 52 (±15) years, 56% were women and 50% had been hospitalised during an acute COVID-19 infection. The prevalence of physical impairment ranged from 23% in functional exercise capacity to 59% in lower extremity muscle strength and function. There was no greater risk of physical impairment in previously hospitalised compared with the non-hospitalised patients. There was a weak to moderate association between physical and cognitive function. The cognitive test scores had statistically significant prediction value for all three outcomes of physical function. In conclusion, physical impairments were prevalent amongst patients assessed for post-COVID-19 condition regardless of their hospitalisation status and these were associated with more cognitive dysfunction.

Post-COVID-19 physical and cognitive impairments and associations with quality of life: a cross-sectional study

“…This study included hospitalized and non-hospitalized post-COVID-19 participants with pre-existing respiratory disease such as asthma, and was conducted before the Omicron peak. In another study, Gunnarsson et al reported lower performance in general cognitive function in hospitalized post-COVID-19 adults compared to the non-hospitalized group, but the TMT-B was similar across the groups ( 7 ). The mean TMT-B in our study is higher than the non-hospitalized group in the study by Gunnarsson et al (154.67 (71.25) seconds vs. 88.8 (44.5)) ( 7 ) that may be explained by the lower educational level of participants in our study.…”

“…In another study, Gunnarsson et al reported lower performance in general cognitive function in hospitalized post-COVID-19 adults compared to the non-hospitalized group, but the TMT-B was similar across the groups ( 7 ). The mean TMT-B in our study is higher than the non-hospitalized group in the study by Gunnarsson et al (154.67 (71.25) seconds vs. 88.8 (44.5)) ( 7 ) that may be explained by the lower educational level of participants in our study. Also, Akinci et al showed worse performance on MoCA and TMT-A tests in young post-COVID-19 adults with mild to moderate disease 21 to 60 days following acute illness compared to healthy controls; however, there were no significant between-group differences in attention span, Stroop time, Stroop Error, and TMT-B tests ( 36 ).…”

“…Studies with mostly non-hospitalized post-COVID-19 participants reported fatigue in 82% ( 4 ), slight to moderate functional limitations (self-reported) in 94% ( 33 ), and handgrip and quadriceps weakness assessed by dynamometer in 39.6% and 35.4%, respectively ( 21 ) at least 3 months after acute COVID-19. Recently, Gunnarsson et al reported the prevalence of physical impairments in non-hospitalized post-COVID-19 participants as 20% in functional exercise capacity (assessed by the 6 min Walk Test) and 59% in lower extremity muscle strength and function (30 s Sit-to-Stand Test), and 33% in handgrip strength 3 months following acute illness ( 7 ). In the present study, MRC-SS was used to assess muscle strength.…”

“…The most common symptoms of post-COVID-19 syndrome are fatigue, pain, muscle weakness, dyspnea, disturbed sleep, and cognitive and mental impairments ( 2 , 6 , 7 ). Complex mechanisms are involved in physical and cognitive impairments in post-COVID-19 syndrome.…”

“…The physical and cognitive systems can influence each other's function ( 9 , 10 ). A recent study showed a significant correlation between physical function (measured by the 6 min walk test, 30 s sit-to-stand test, and handgrip strength) and cognitive function (measured by the Screen for Cognitive Impairment in Psychiatry-Danish version (SCIP-D) and Trail Making Test-Part B (TMT-B)) in post-COVID-19 individuals that can denote common mechanisms triggering both physical and cognitive impairments ( 7 ).…”