Social Cognitive Determinants of Physical Activity in African-Americans with Multiple Sclerosis

Background: Epidemiology conveys that multiple sclerosis (MS) is more prevalent in Caucasians than in African-Americans. However, African-Americans may experience a more aggressive MS disease course than Caucasian counterparts, thereby greatly influencing physical activity levels in African-Americans with MS. This underscores the importance of identifying theoretical determinants of physical activity that can inform the design of behavioral interventions among African-Americans with MS.

Objectives: This study examined variables from social-cognitive theory as determinants of physical activity in African-Americans with MS.

Methods: 151 African-American with MS were recruited through the NARCOMS registry and completed a battery of questionnaires. The battery of questionnaires included information on demographic and clinical characteristics, physical activity, exercise self-efficacy, function, social support, exercise outcome expectations, and exercise goal setting and planning. The data were analyzed using path analysis in Mplus. 

Results: The social-cognitive model provided a good fit for the data (CFI=.996, SRMR=.020). Self-efficacy (β=.16), function (β=.22), goal-setting (β=.15), and planning (β=.19) had statistically significant direct effects on physical activity. Self-efficacy further had an indirect effect via function (β=.12). This model explained 27% of variance in physical activity behavior.

Conclusions: Researchers should consider self-efficacy, function, goal-setting, and planning as targets when designing behavioral interventions for increasing physical activity among African-Americans with MS.