Background
Fatigue is a common experience among persons diagnosed with multiple sclerosis
(MS). Fatigue negatively influences quality of life, interferes with activities of daily
living, and impairs the ability to maintain gainful employment (Amato et al., 2001; Julian,
Vella, Vollmer, Hadjimichael, & Mohr, 2008; Smith & Arnett, 2005). Mechanisms underlying the
pathophysiologic determinants of fatigue in MS are poorly understood and effective
treatments to manage fatigue present a challenge (Krupp,
Christodoulou, & Serafin, 2010). While the use of pharmacologic
therapies (e.g., Modafinil) is recommended to treat symptomatic fatigue, under-treatment
of fatigue is common (Hatzakis et al., 2005;
Brichetto, Messmer, Mancarki & Solaro,
2003). Better long-term management and symptomatic relief may be provided by
the use of non-pharmacologic treatments such as increased physical activity, energy
conservation, and cognitive behavioral therapy (Motl,
McAuley & Snook, 2005; van Kessel et
al., 2008; McCullagh, Fitzgerald, Murphy,
& Cooke, 2008).
Methods
The purpose of this study was to explore the physical, cognitive and
psychosocial dimensions of fatigue impact among persons with longstanding MS - defined
here as having been diagnosed with MS for 17 years or more. A sample of 331 participants
with MS completed surveys measuring fatigue impact, MS-related functional limitation,
depressive symptoms, barriers to health promotion, personal resources, and health
promoting behaviors.
Results
MS-related functional limitation and depressive symptoms were the strongest
predictors of fatigue impact. MS-related functional limitation explained the greatest
amount of variance in models predicting physical and psychosocial fatigue impact while
depressive symptoms explained the most variance in models predicting total and cognitive
fatigue impact. Barriers to health promotion explained the least amount of variance
among the models. Personal resources and health promoting behaviors were not significant
predictors of fatigue impact in this study.
Conclusion
Interventions aimed at reducing MS-related functional limitations, depressive
symptoms, and barriers to health promotion may have beneficial influences on fatigue
impact while actions designed to promote personal resource adequacy as well as
engagement in health promoting behaviors may not translate into improvements in fatigue
impact in persons with MS.