Differences in upper and lower limb function in persons with multiple sclerosis with vascular comorbidities

Vascular comorbidities are more prevalent in persons with multiple sclerosis (PwMS) than the general population. There is a paucity of literature on vascular comorbidity in PwMS and the effect on upper (UL) and lower limb (LL) function.

To examine the difference between UL and LL function for PwMS with and without vascular comorbidities (hypertension, hypercholesterolemia, diabetes, or heart disease) and determine whether specific comorbidities are associated with UL or LL dysfunction.

This secondary analysis of a cross-sectional study collected LL (Timed 25-foot Walk: T25FW, Timed-Up and Go: TUG) and UL function (Finger to Nose Test: FNT, Nine-Hole Peg Test: NHPT, Grip Strength, Box and Block Test: BBT), which were transformed into z-scores. Bivariate statistics compared function between vascular comorbidity status. Individual linear regressions adjusted for age, disease duration, race, education, and gender. Exploratory regressions for significant results examined the individual vascular comorbidities in the same model.

PwMS with vascular comorbidities had worse performance on functional measures. After adjusting for covariates, vascular comorbidity was related to worse performance for the T25FW, TUG, and FNT. Diabetes was associated with reductions on the T25FW (b=-0.55, 95 % CI:1.00, -0.11, P = 0.014) and TUG (b=-0.45, 95 % CI:0.90, -0.01, P = 0.047).

Reductions in walking speed (T25FW), balance and physical mobility (TUG), and UL coordination (FNT) remained significant after accounting for covariates, with diabetes significantly associated with the T25FW and TUG. These findings highlight the compounding effects of vascular conditions and MS on function, and can help guide individualized education, management plans, and treatment to PwMS.