Sofi A. Andersson, Anna Danielsson, Fredrik Ohlsson, Jan Wipenmyr, Margit Alt Murphy
Clinical Neuroscience, Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden. E-mail: sofi.andersson@neuro.gu.se
DOI: 10.2340/16501977-2838

Objective: To determine to what extent accelerometer-based arm, leg and trunk activity is associated with sensorimotor impairments, walking capacity and other factors in subacute stroke.
Design: Cross-sectional study.
Patients: Twenty-six individuals with stroke (mean age 55. 4 years, severe to mild motor impairment).
Methods: Data on daytime activity were collected over a period of 4 days from accelerometers placed on the wrists, ankles and trunk. A forward stepwise linear regression was used to determine associations between free-living activity, clinical and demographic variables.
Results: Arm motor impairment (Fugl-Meyer Assessment) and walking speed explained more than 60% of the variance in daytime activity of the more-affected arm, while walking speed alone explained 60% of the more-affected leg activity. Activity of the less-affected arm and leg was associated with arm motor impairment (R2 = 0. 40) and independence in walking (R2 = 0. 59). Arm activity ratio was associated with arm impairment (R2 = 0. 63) and leg activity ratio with leg impairment (R2 = 0. 38) and walking speed (R2 = 0. 27). Walking-related variables explained approximately 30% of the variance in trunk activity.
Conclusion: Accelerometer-based free-living activity is dependent on motor impairment and walking capacity. The most relevant activity data were obtained from more-affected limbs. Motor impairment and walking speed can provide some information about real-life daytime activity levels.

Activity data from accelerometers can help clinicians to better understand factors limiting physical activity levels. This study aimed to determine to what degree arm, leg and trunk activity, measured with accelerometers, is associated with sensorimotor impairments, walking and other factors in people with stroke in the subacute stage of recovery. Real-life activity, measured by accelerometers, was primarily associated with motor impairment and walking speed. Spasticity, dependency in walking, and disability level also showed association with real-life activity, although to a lesser degree. Accelerometers, placed on the more-affected wrist and ankle, provided most relevant clinical information and are therefore recommended for research and clinical practice. The strong associations observed in this study suggest that when accelerometers are not available, clinical assessments of arm motor function and walking speed can provide some information on real-life activity levels in people with stroke.

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