Changes in fatigue following a behavioral treatment for memory impairment in Multiple Sclerosis: A randomized clinical trial
Bridging Science and Practice
Fatigue is one of the most common and debilitating symptoms of Multiple Sclerosis (MS), negative impacting an individual’s cognitive functioning and overall quality of life. The current study evaluated the impact of a behavioral memory intervention, the modified Story Memory Technique (mSMT), on self-reported fatigue.
Objective: Evaluate the effects of a 10-session, behavioral, highly-manualized memory retraining protocol, the modified Story Memory Technique (mSMT), on self-reported fatigue in MS patients.
Participants: 72 participants with MS were randomly assigned to either a treatment group (N=37) or a placebo-control group (N=35).
Procedure: All participants received comprehensive baseline neuropsychological (NP) assessment. Global assessment of functioning included a self-report measure of fatigue (Modified Fatigue Impact Scale; MFIS). Participants were then randomly assigned to the two groups. The treatment group underwent a10-session memory retraining protocol (modified Story Memory Technique; mSMT). The control group engaged in similar exercises during the 10 sessions, but did not receive training in visualization and context, the key ingredients of the mSMT . Following treatment, all participants completed a repeat NP evaluation which included most of the baseline NP and functional measures, including the MFIS. All participants will undergo a long-term follow-up NP and functional assessment at 6 months post-treatment.
Hypothesis: Cognitive retraining will result in a reduction in self reported fatigue post-treatment due to better and more efficient learning abilities
a) The treatment group will exhibit reduced self-reported fatigue following treatment, as measured by a change in MFIS scores from baseline to immediate follow-up. Participants in the control group will not exhibit a significant change in MFIS scores.
b) There will be a significant difference between the treatment group and the control group on MFIS scores at the immediate follow-up evaluation, such that treatment participants will report significantly less fatigue post treatment as compared to controls.
Results: There were no significant differences between the groups on any demographic variables. When examining differences in self-reported fatigue from pre-treatment to post-treatment, there were no significant differences between the treatment and placebo-control groups. However, there was a significant difference in the change in self reported fatigue post treatment when comparing “responders” to treatment versus the control group. Specifically, contrary to our expectations, responders to treatment reported greater self-reported fatigue at follow-up as compared to baseline (t (2, 13) = -1.95, p = .073, trend), while participants in the placebo-control group reported no changes in self-reported fatigue (t (2, 34) = 1.458, p = .154). Treatment responders showed significantly higher levels of self-reported fatigue at follow-up as compared to placebo-control particpants (F (1, 49) = 12.133, p =.001). No such differences were found at baseline (F (1, 59) = .524, p =.472).
Conclusions: Increase in fatigue following treatment was specific to those participants in the treatment group that showed a positive response to treament in terms of their memory ability. The increase in fatigue was significant as compared with control participants. This finding likely reflects the fact that the application of the newly learned techniques is effortful. We hypothesize that as these participants continue to utilize these techniques, the application of the techniques will become more automatic, will require less cognitive effort and therefore will result in less self-reported fatigue over time. This hypothesis will be systematically evaluated in the future, once 6-month follow-up data collection is complete.