Associations among physical activity, perception of stress, and relapse occurrence in multiple sclerosis

Background: Relapsing-remitting multiple sclerosis (RRMS) is a chronic, immune-mediated disease that is characterized by relapses or periods of worsening symptoms (Lublin & Reingold, 1996). The occurrence of a relapse has been associated with experiencing a stressful event (Mohr, Hart, Julian, Cox, & Pelletier, 2004). Physical activity could potentially influence relapse occurrence directly or indirectly through attenuation of the stress response, but neither of these relationship have been investigated in people with MS. Two theoretical models, the Transactional Model of Stress and Coping and the Cross-Stressor Adaptation Hypothesis, could possibly provide an explanation for how stress is involved in the relationship between physical activity and relapse occurrence. Objective: The two aims of this retrospective study were to determine: 1) Is physical activity associated with a decreased number of relapses within a year; and 2) Is the relationship between physical activity and relapse occurrence mediated or moderated by stress? Methods: The sample included 47 females with RRMS who had characteristics for increased risk of relapse occurrence (female, short disease duration, young age of adult onset). Participants completed the Perceived Stress Scale (PSS), Modified Activity Questionnaire (MAQ), and a recall of any relapses during the previous year. Participants further wore a pedometer for 7 days. Results: Nineteen or 40% of the participants had a relapse during the previous year. There were statistically significant differences between those who did and did not have a relapse in the previous year for pedometer steps (t = 2.13, p < 0.05), PSS (t = 2.05, p < 0.05), and MAQ (t = 1.96, p < 0.05).The occurrence of a relapse was positively associated with PSS (r = .29) and negatively associated with MAQ (r = –.29) and pedometer (r= –.30). The regression analyses for mediation effects showed the relationship between physical activity (i.e. both pedometer and MAQ separately) were slightly attenuated, but non-significant when relapse occurrence was regressed on both physical activity and PSS. For moderation, pedometer steps were significantly correlated with relapse in the low stress group (r = .435) but not in the high stress group (r = .076), and MAQ was significantly correlated with relapse occurrence in the high stress group (r = .345), but not in the low-stress group (r = .207). Conclusion: Physical activity was moderately, significantly, and inversely related to relapse occurrence in persons in the early stages of RRMS. This means that physical activity behavior could potentially be a determinant of relapse occurrence or that inactivity could be a consequence of having a relapse. There were weak and inconsistent results with perception of stress as a mediator or moderator of the relationship between physical activity and relapse occurrence in MS. These results did not fully support the Transactional Model of Stress and Coping or the Cross-Stressor Adaptation Hypothesis for understanding the decrease in relapses seen with physical activity in persons with MS.

Name thesis:degree_name

M.S.

Level thesis:degree_level

Thesis

Discipline thesis:degree_discipline

Kinesiology

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2011

Author dc:creator

• Weikert, Madeline L.

Contributors dc:contributor

• Motl, Robert W.

• Physical Activity
• Perception of Stress
• Relapse occurrence
• Multiple Sclerosis

Statement dc:rights

• Copyright 2011 Madeline L. Weikert

Language dc:language

en

Handle dc:identifier

http://hdl.handle.net/2142/26048

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/26048