Upper Limb Performance in Daily Life Approaches Plateau Around Three to Six Weeks Post-stroke

Abstract

Background. Wearable sensors allow for direct measurement of upper limb (UL) performance in daily life. Objective. To map the trajectory of UL performance and its relationships to other factors post-stroke. Methods. Participants (n = 67) with first stroke and UL paresis were assessed at 2, 4, 6, 8, 12, 16, 20, and 24 weeks after stroke. Assessments captured UL impairment (Fugl-Meyer), capacity for activity (Action Research Arm Test), and performance of activity in daily life (accelerometer variables of use ratio and hours of paretic limb activity), along with other potential modifying factors. We modeled individual trajectories of change for each measurement level and the moderating effects on UL performance trajectories. Results. Individual trajectories were best fit with a 3-parameter logistic model, capturing the rapid growth early after stroke within the longer data collection period. Plateaus (90% of asymptote) in impairment (bootstrap mean ± SE: 32 ± 4 days post-stroke) preceded those in capacity (41 ± 4 days). Plateau in performance, as measured by the use ratio (24 ± 5 days), tended to precede plateaus in impairment and capacity. Plateau in performance, as measured by hours of paretic activity (41 ± 6 days), occurred at a similar time to that of capacity and slightly lagged impairment. Modifiers of performance trajectories were capacity, concordance, UL rehabilitation, depressive symptomatology, and cognition. Conclusions. Upper limb performance in daily life approached plateau 3 to 6 weeks post-stroke. Individuals with stroke started to achieve a stable pattern of UL use in daily life early, often before neurological impairments and functional capacity started to stabilize.

Keywords: outcome assessment; recovery; rehabilitation; stroke; upper extremity.

Figure 1.

STROBE chart of participant enrollment.

Figure 2.

A: Generic 3-parameter logistic curve to illustrate the model and parameters. Most participant data fit the upper half of the model, as shown in the individual example in B. B: Individual examples showing data and fit with model, gray = UEFM, black = ARAT, and blue = use ratio. The UEFM and ARAT data correspond to the left y-axis and the use ratio corresponds to the right y-axis. Arrows represent time to plateau (90% of asymptote). Predicted data from each participant for impairment (C), capacity (D), and performance (E&F).

Figure 3.

Timing of plateaus across measures obtained from bootstrapping procedures. Values are means and 95% confidence intervals.

Figure 4.

Illustration of predicted higher (+ 1 SD) vs. lower (−1 SD) moderator scores on performance trajectories. Data are modeled estimates at the moderator value, not cohorts of patients. A&B: ARAT score at four weeks; C&D: concordance; E&F: CES-D score at 2 weeks.