Perceived control is a concurrent predictor of activity limitations in patients with chronic idiopathic axonal polyneuropathy.
OBJECTIVE
To investigate (1) whether control perceptions (person's perception of ease or difficulty of performing behavior) and emotions contribute to activity limitations and if so (2) whether these variables mediate the relation between impairment and activity limitations in patients with chronic idiopathic axonal polyneuropathy (CIAP).


METHODS
Cross-sectional study.


METHODS
Outpatient clinics of a university medical center.


METHODS
Fifty-six patients diagnosed with CIAP.


METHODS
Not applicable.


METHODS
Control perceptions about performing activities (questionnaire based on the theory of planned behavior), emotions (Hospital Anxiety and Depression Scale), activity limitations (performance: Shuttle Walk Test [SWT]; self-report: Medical Outcomes Study 36-Item Short-Form Health Survey [SF-36] physical functioning subscale, self-reported ability to walk), and physical impairments (muscle strength, sensory function).


RESULTS
Control perceptions significantly (P<.01) correlated with all measures of activity limitations (r range, .58-.69). Hierarchical multiple regression analyses showed that perceived control explained 9% of the variance in the SWT (beta=.34, P<.01), 12% in the SF-36 (beta=.40, P<.01), and 24% in ability to walk (beta=.54, P<.01). In all measures of activity limitations, perceived control significantly mediated the effect of impairment.


CONCLUSIONS
Perceived control explained and mediated variance in activity limitations, whereas emotions did not. This suggests that increasing patients' perceptions of control might enhance performance of activities, even without changes in impairment.
Schröder
Carin
C
Department of Neurology and Neurosurgery, Rudolf Magnus Institute of Neuroscience, Sections of Rehabilitation Medicine, University Medical Centre Utrecht, Utrecht, The Netherlands. c.schroeder@umcutrecht.nl
Johnston
Marie
M
Teunissen
Laurien
L
Notermans
Nicolette
N
Helders
Paul
P
van Meeteren
Nico
N
D000203:Activities of Daily Living / Q000523:psychology*; D000368:Aged; D000704:Analysis of Variance; D001007:Anxiety / Q000209:etiology; D001294:Attitude to Health; D002908:Chronic Disease; D003430:Cross-Sectional Studies; D003863:Depression / Q000209:etiology; D004644:Emotions; D005080:Exercise Test; D005163:Factor Analysis, Statistical; D005260:Female; D006801:Humans; D033182:Intention; D007389:Internal-External Control; D008297:Male; D018908:Muscle Weakness / Q000209:etiology; D009426:Netherlands; D010146:Pain / Q000209:etiology; D011115:Polyneuropathies / Q000150:complications / Q000503:physiopathology* / Q000523:psychology*; D011237:Predictive Value of Tests; D011582:Psychological Theory; D012044:Regression Analysis; D020377:Self Efficacy; D012720:Severity of Illness Index; D011795:Surveys and Questionnaires; D016138:Walking / Q000523:psychology