A cross-sectional study to assess an association between upper extremity function and functional walking capacity in chronic stroke survivors

Background: The Six-Minute Walk Test (6MWT) predicts community ambulation in stroke patients.These patients frequently face several disabilities, including upper extremity dysfunction.Since upper extremity (UE) dysfunction is related to walking disability, we expect that the UE function is associated with the 6MWT.So far, no study has directly investigated the association between UE function and the 6MWT.Aims: To examine the association between UE function and the 6MWT in stroke survivors adjusted for balance and gait problems.Methods: Subjects were randomly recruited from the general population and the Academic Hospital Paramaribo.UE function was measured using the handgrip strength (HGS) test, Disabilities of the Arm Shoulder and Hand (DASH) survey and Stroke Impact Scale (SIS) survey.Functional walking capacity was measured by the 6MWT.Functional balance was measured using the Berg Balance Scale (BBS).Step length ratio (SLR) and step width (SW) were used to assess gait.The median (range) or mean±SD are presented.Results: In fifty subjects with a mean age of 58.2±9.5 years, we demonstrated that the mean 6MWT (297.9±19.8m)correlated with the mean paretic HGS (19.1±14.9kg,r=0.77, p<0.001) and non-paretic HGS (31.1±9.7kg,r=0.41, p=0.003), but not with the DASH and SIS surveys.The 6MWT correlated with the BBS (55.0(30.0-56.0),r=0.51, p<0.001),SLR (0.9(1.0-2.0),r= -0.29, p=0.044), but did not correlate with SW.After adjusting for BBS and SLR, paretic HGS explained 62% of the variance in 6MWT.The relationship between non-paretic HGS and 6MWT was influenced by the BBS and SLR (p<0.05,R 2 =0.39).Conclusions: Paretic handgrip strength predicts 6MWT performance after adjusting for balance and gait asymmetry.The 6MWT is limited by stroke-related impairments such as handgrip strength, balance control and gait asymmetry.Further studies are warranted for assessment of causal effects between these variables.