Publication
Research Article
Background: The period surrounding the diagnosis of multiple sclerosis (MS) is physically and emotionally challenging. Positive psychology (PP) exercises (ie, systematic activities to cultivate well-being) have been shown to increase positive emotional responses, such as positive affect, and may aid in psychosocial adjustment to MS.
Methods: Participants were randomly asigned 1:1 to a 5-week, at-home, self-directed PP intervention or a waitlist control condition. The PP intervention consisted of 5 previously tested PP exercises. Feasibility was defined as the proportion of participants who completed at least 4 of the 5 PP exercises. Acceptability was determined by participant ratings of ease and utility (0-10 scale) reported at the completion of each exercise. The effects of the PP intervention on a battery of patient-reported outcome measures were also examined using linear mixed-effects models.
Results: Thirty participants were enrolled in the study, and 70% met the a priori threshold for feasibility. Mean ease scores across the exercises ranged from 7.0 to 7.9 (scale of 0-10), and mean utility scores ranged from 7.0 to 8.1. There were statistically significant increases in positive affect (6.68; 95% CI, 2.58-10.78; P = .003) and optimism (3.03; 95% CI, 0.75-5.31; P = .01) in the intervention group compared with the waitlist control group at 5 weeks.
Conclusions: A 5-week at-home self-directed PP intervention was feasible and acceptable to individuals with new diagnoses of MS. Larger trials with longer follow-up are needed to fully understand the benefits of PP training to improve adjustment to MS diagnosis, which may lead to better psychosocial and health outcomes.
From the Brigham MS Center, Department of Neurology, Brigham and Women’s Hospital, Boston, MA (BIG, BCH); Department of Psychiatry, Massachusetts General Hospital, Boston, MA (JCH, CMC); Biostatistics Center, Massachusetts General Hospital, Boston, MA (BCH); Harvard Medical School, Boston, MA (BIG, JCH, CMC, BCH). Correspondence: Bonnie I. Glanz, PhD, 60 Fenwood Rd, Boston, MA 02115; email: bglanz@bwh.harvard.edu.
Multiple sclerosis (MS) is a chronic autoimmune disease of the central nervous system that affects nearly 1,000,000 individuals in the United States.1 An MS diagnosis is typically made between the ages of 20 and 40, a time of significant personal and professional growth.2 The period surrounding diagnosis has been described as stressful and psychologically demanding.3 Anxiety4-8 and depression6-8 are common, and health-related quality of life (HRQOL)5 is reduced. There is some evidence to suggest that providing much-needed support to people with MS at the time of diagnosis may contribute to better psychosocial and health outcomes.9
Positive emotional constructs, such as positive affect and optimism, have been shown to aid in the adjustment to chronic disease.10,11 Positive psychology (PP) focuses on helping individuals experience greater life satisfaction through specific, intentional activities or exercises designed to increase the frequency and intensity of specific psychological constructs, such as positive affect and optimism. PP interventions use systematic exercises, such as writing a letter of gratitude or completing a series of enjoyable and meaningful activities.12 We previously adapted a PP intervention originally developed for patients with acute coronary syndrome12,13 for people with MS. Thirty people with MS were randomly assigned 1:1 to a 5-week at-home PP intervention or waitlist control condition.14 Participants completed 1 PP exercise and had 1 telephone call with the study trainer each week to introduce each exercise and to review completed exercises and their effects on well-being. The intervention was feasible and well-accepted by people with MS, and we observed a significant increase in positive affect following PP training. We also observed increases in optimism, general health, and resilience, and a decrease in anxiety. Despite these positive results, the intervention required significant involvement on the part of a study trainer, limiting its scalability, and the mean MS disease duration of study participants was more than 20 years, limiting its generalizability.
Considering that the time surrounding a new MS diagnosis is challenging, interventions to support improved adjustment are needed. Our prior work demonstrated that PP exercises could improve positive constructs in people with MS with long-standing disease. In order to determine whether these same exercises have the potential to increase positive affect and optimism and aid in the adjustment to a new MS diagnosis, we conducted a phase 1 randomized controlled trial (RCT) of a similar PP intervention in 30 people with new diagnoses of MS. Rather than relying on a study trainer, we involved a study facilitator whose primary responsibility was to collect pre- and postintervention ratings. The primary outcome measures were the intervention’s feasibility (ie, proportion of participants who completed at least 4 of the 5 study exercises) and acceptability (ie, mean ease and utility scores). Secondary outcomes were changes in positive affect, optimism, resilience, anxiety, depression, fatigue, and several other HRQOL-related domains.
Participants
Thirty participants were recruited from the Brigham MS Center at Brigham and Women’s Hospital in Boston, Massachusetts.Inclusion criteria included being 18 years of age or older and having onset of MS symptoms within the past 2 years, leading to a diagnosis of MS or clinically isolated syndrome according to the revised McDonald criteria.15 Study flyers were given to treating neurologists to be distributed to eligible patients at the time of their visits. Expanded Disability Status Scores (EDSS) were taken from the electronic medical record. Study recruitment began in July 2022, and study enrollment was completed in August 2024. This study was approved by the Mass General Brigham Human Research Committee, and all the participants provided written informed consent. The study was also registered with ClinicalTrials.gov (Identifier: NCT06891937).
Procedures
In this parallel-group, 1:1 randomized trial, participants were randomly assigned to the intervention or waitlist control groups using a computerized random number generator with a permuted block design, with block sizes of 2 and 4, generated by the study statistician (B.C.H.) with the ralloc command in Stata version 17. The random assignments were placed in sequentially numbered sealed envelopes that were opened by the study investigator (B.I.G.) after study enrollment. Neither participants nor study investigators were blinded to treatment group assignment. After random distribution, all study participants were asked to complete a battery of patient-reported outcome (PRO) measures in REDCap, a free, secure, web-based application that supports data capture for research studies. At the beginning of the intervention phase (phase 1: weeks 1-5), participants in the intervention group were given a participant manual and asked to complete a PP exercise each week for 5 consecutive weeks. Prior to completing each exercise, participants rated their feelings of happiness (not happy/very happy), mental organization (not organized/very organized), and optimism (not optimistic/very optimistic) using 3 scales of 0 to 10. At the completion of each exercise, participants rated its ease and utility (on a
0-10 scale, with 10 representing optimal ease and utility). They also rated their feelings of happiness, mental organization, and optimism. Finally, participants were asked to indicate what was helpful about the exercise, what was less helpful or difficult about the exercise, and what could make it better. Each week, participants in the intervention group received a call from the study facilitator (B.I.G.). The facilitator did not introduce exercises or interfere with their completion. The weekly calls were strictly used to collect participants’ before-exercise and after-exercise ratings, and any additional details about what was helpful, or less helpful/difficult, about each exercise, and to schedule the next call. If the weekly exercise was not completed, the call was rescheduled. The waitlist control group had no study activities and received no calls from the study facilitator during the first 5 weeks after enrollment. At the completion of the intervention phase, all participants were emailed a link to complete the PRO battery in REDCap. At the beginning of the extension phase (phase 2: weeks 6-10), participants in the control group received their study participant manuals in the mail and completed the intervention as described above. The intervention group did not complete any study activities or receive any calls during the extension phase. At the completion of the extension phase, all participants were emailed a link to complete the PRO battery in REDCap.
Study Intervention
The PP intervention consisted of 5 weeks of PP training using the exercises detailed in Table 1. These exercises have all been described by Huffman et al12 and are well-accepted and easy for participants to complete.
Table 1. Description of Positive Psychology Exercises
Outcome Measures
The primary outcome measures were the feasibility and acceptability of the intervention. We assessed feasibility by calculating the proportion of participants who completed at least 4 of the 5 exercises before their weekly calls with the study facilitator. The intervention would be considered feasible if at least 50% of participants met the feasibility end point. In addition, we examined exercise-specific ratings of ease and utility to measure the acceptability of each exercise. Ease and utility were measured using Likert scales scored from 0 to 10, 1 for ease of completion (0 = very difficult; 10 = very easy) and 1 for overall utility (0 = not helpful; 10 = very helpful). The intervention would be considered acceptable if the mean ease and utility scores were greater than or equal to 7.0. We also assessed the change in happiness, mental organization, and optimism from before to after exercise. Feelings of happiness, mental organization, and optimism about the future were measured using Likert scales scored from 0 to 10 for happiness (0 = not happy; 10 = very happy), mental organization (0 = not organized; 10 = very organized), and optimism (0 = not optimistic; 10 = very optimistic).
At enrollment, 5 weeks, and 10 weeks, participants completed a battery of PRO measures in REDCap. The PRO battery included the Positive and Negative Affect Schedule (PANAS),16 Life Orientation Test–Revised (LOT-R),17 the Brief Resilience Scale (BRS),18 and Quality of Life in Neurological Disorders (Neuro-QOL).19 PANAS is a 20-item self-report measure of separate scales assessing positive and negative affect. LOT-R is a 10-item questionnaire to measure dispositional optimism. BRS is a 6-item self-report questionnaire that measures an individual’s ability to rebound from adversity. Neuro-QOL is a set of self-report measures developed through a collaborative, multisite initiative to construct psychometrically sound and clinically relevant HRQOL tools for individuals with neurological conditions such as stroke, MS, and Parkinson disease that was sponsored by the National Institute of Neurological Disorders and Stroke. It covers 12 domains: ability to participate in social roles and activities, anxiety, cognitive function, depression, emotional and behavioral dyscontrol, fatigue, lower extremity function, positive affect and well-being, satisfaction with social roles and activities, sleep, stigma, and upper extremity function.
Statistical Analysis
We chose a sample size of 30 total participants to estimate the proportion of participants who would complete the intervention with the precision of approximately ± 0.05, based on a binomial CI. The proportion of participants who completed the intervention and the associated exact binomial 95% CI were used to estimate feasibility. For each exercise, the mean ease and utility scores, and the before-exercise; after-exercise; and change in happiness, mental organization, and optimism scores, were estimated with the corresponding 95% CIs using 1-sample t tests. The overall ease and utility scores for the intervention were calculated across the exercises using a linear mixed-effects model with a random intercept to account for repeated observations.
To estimate the treatment effect on the change in PRO measures, we used a mixed model for repeated measures with a categorical effect for time, group, and the time by group interaction. An unstructured covariance matrix for the within-subject residuals was used to account for the correlation within a subject. Effect sizes were calculated as the time by group interaction divided by the SD of the difference between week 5 and baseline, calculated using the variance components from the model. All available PRO measures from baseline and week 5 were included in the analysis, and the mixed models assume that missing data were missing at random. We also estimated the within-person change by comparing preintervention scores with postintervention scores of participants from both groups (intervention and waitlist control) using the same model with only a categorical effect of time and an unstructured covariance matrix. Finally, in order to understand whether improvements on PROs were maintained after the completion of the intervention, we determined the proportion of participants who showed improvement on each PRO at week 5 who maintained at least 50% of that improvement at week 10. Only participants in the intervention group had data collected to contribute to this analysis. All statistical analyses were completed in the statistical package R version 4.4.2 and its nonlinear mixed-effects models library (R Foundation).
Thirty patients were enrolled in the study. The demographic characteristics of the 2 groups are provided in Table 2. The enrollment and retention of study participants are outlined in the Figure. The 15 participants randomly distributed to the intervention group and the 14 participants randomly assigned to the waitlist control group completed baseline PROs. One participant, who asked to be sent a link to complete baseline PROs from home, did not complete the questionnaires and was withdrawn from the study. Baseline PRO scores for both groups are presented in Table S1 (supplemental materials are available in a PDF at the end of the online article). At baseline, there were significant differences between groups on PANAS negative affect, LOT-R optimism, Neuro-QOL depression, Neuro-QOL lower extremity function, Neuro-QOL positive affect and well-being, and Neuro-QOL satisfaction with social roles. For all measures with significant differences between groups, the waitlist control group reported better function.
Table 2. Baseline Demographic Characteristics
Figure. Study Enrollment and Retention
In the intervention group, 5 of 15 (33%) participants withdrew from the study: 3 did not begin the intervention, and 2 withdrew after completing 2 or 3 exercises. In addition, 1 participant who completed the intervention did not complete week 10 PROs. In the waitlist control group, 4 of 15 (27%) participants withdrew from the study prior to beginning the intervention. Two of the 4 did not complete week 5 PROs. The remaining participants completed all 5 study exercises and follow-up assessments. The estimated feasibility of the intervention (proportion who completed at least 4 of the 5 sessions) was 70% (95% CI, 50.6-85.3). The estimated average ease and utility scores for each exercise are presented in Table S2. Mean ease scores ranged from 7.0 to 7.9, with Exercise 5, Remembering Past Successes (7.9), and Exercise 4, Enjoyable and Meaningful Activities (7.6), rated highest. Mean utility scores ranged from 7.0 to 8.1. The highest-rated exercises in terms of utility were Exercise 3, Gratitude Letter (8.1), and Exercise 5, Remembering Past Successes (8.0). The mean scores after combining all of the exercises were 7.3 (95% CI, 6.7-7.9) for ease and 7.5 (95% CI, 7.0-8.0) for utility. Improvements in happiness, mental organization, and optimism were seen in the before-exercise to after-exercise ratings for each of the 5 exercises (Table S2). The largest mean improvements in happiness and mental organization followed Exercise 4, Enjoyable and Meaningful Activities. The largest mean improvement in optimism followed Exercise 3, Gratitude Letter.
Table 3 shows the between-group comparisons of change from baseline on all PROs at 5 weeks. There were statistically significant differences between the groups for PANAS positive affect (estimated group difference = 6.68 [95% CI, 2.58-10.78]) and LOT-R optimism (estimated group difference = 3.03 [95% CI, 0.75-5.31]). The within-subject change on each of the outcome measures is provided in Table S3. PANAS positive affect, which showed a significant treatment effect, also showed a significant change with time when intervention and waitlist control participants were combined (mean within-subject change over the intervention: 4.42 [95% CI, 1.78-7.06]). A significant within-subject change was also seen for Neuro-QOL fatigue (mean within-subject change over the intervention: –3.08 [95% CI, –5.53 to –0.63]). Finally, the proportions of participants who maintained at least 50% of the improvement observed on week 5 PROs at week 10 are presented in Table S4. A majority of participants who experienced improvement maintained that improvement across most PROs, but the number of participants contributing to each analysis was small.
Table 3. Estimation of Treatment Effect During First Study Period
In this phase 1 RCT, we demonstrated the feasibility and acceptability of a 5-week at-home, self-directed PP intervention for people with newly diagnosed MS. Seventy percent of participants who enrolled in the study completed the PP intervention, above our a priori threshold of 50%, but lower than the 93% of participants who completed our previous PP study. In addition, the mean ease score was 7.3, and the mean utility score was 7.5, also above the a priori threshold of 7.0, but lower than the mean ease (8.3) and utility (8.5) scores reported in the earlier trial. Age, disease duration, and the lack of a study trainer may explain these discrepancies. In the first study, the mean age was about 54 years and the mean disease duration was more than 20 years, whereas in this study, the mean age was about 37 years and the mean disease duration was about 1.5 years. In addition to the challenges of adapting to a new diagnosis, the younger participants in this trial were likely navigating different life stages, including career development and family building. These added pressures and responsibilities may have contributed to the fact that 7 participants who enrolled in the study (3 participants in the intervention group and 4 participants in the waitlist control group) did not begin the intervention (23%). In some cases, participants indicated that they were too busy, tired, or overwhelmed to participate. In other instances, they did not respond to follow-up emails or telephone calls. Two participants in the intervention group withdrew from the study after completing 2 or 3 of the 5 exercises. One participant explained that the exercises were too difficult and made her feel terrible. The other participant indicated that she was under too much stress to continue. It is likely that the emotional upheaval created by a new MS diagnosis contributed to the inability of some participants to complete the study. Additional support and engagement with a study trainer may have improved the intervention’s feasibility and acceptability among newly diagnosed people with MS.
We observed a significant increase in positive affect and optimism from weeks 1 through 5 in participants in the intervention group compared to those in the waitlist control group. Positive affect has previously been identified as an important element in the successful adjustment to chronic disease.10 A review of psychological correlates of adjustment in people with MS concluded that various constructs associated with positive psychology, such as optimism, were related to better adjustment outcomes.20 This is in contrast to pessimism, which was related to worse adjustment.20 When we examined the within-subject change across all study participants after the 5-week intervention, we found a statistically significant increase in positive affect and a statistically significant decrease in fatigue. Fatigue is the most common MS symptom, and it is associated with significant patient morbidity. A recent study of 5695 people with MS by Young et al21 analyzed fatigue, disability, perceived health, pain, and their relationship to QOL. They found that fatigue was the dominant factor influencing QOL in people with MS, suggesting that treatment of fatigue has the potential to improve QOL.
In recent years, a small number of interventions designed specifically to foster adjustment to a new MS diagnosis have been published. These interventions use different strategies to target psychological, social, and/or functional outcomes, including mindfulness;22 integrated psychological, social, and physical activities;2 and combined psychotherapy and physical therapy.23 Given the limited number of interventions designed specifically for newly diagnosed people with MS, the ability to improve their positive affect and optimism and decrease fatigue using a PP intervention is promising. One of the advantages of this PP intervention is that it is self-directed and can be made available at no cost. This would require buy-in and distribution by treating neurologists or health care systems, but would not be dependent on reimbursement.24
Although we have demonstrated the feasibility of the self-directed PP intervention, we acknowledge that it may not be the optimal mode of delivery. Our previous PP trial, which included engagement with a study trainer, had higher feasibility, ease, and utility scores. Another advantage of PP training for people with MS is that PP skills learned at the time of diagnosis can be applied throughout the disease course. The use of booster or continuation sessions may be required to maintain the benefits of early PP training.25 Although the PP intervention is promising, it does not address the informational or emotional support needs of newly diagnosed people with MS. Previous studies have suggested that after diagnosis, people want information about MS causes, symptoms, prognosis, treatment, and management.9 Previous studies have also suggested that newly diagnosed people with MS feel that their emotional needs are ignored, and that they feel lonely and abandoned by physicians, friends, and family.9 Further, the PP intervention does not include social or physical activities that might contribute to better overall health and well-being. The ultimate goal is to match the intervention and the timing of the intervention to the baseline characteristics and needs of the individual.
This study has several limitations. First, it was a phase 1 RCT with a small sample size and numerous outcome measures. This may have limited our ability to see statistically significant changes across broader HRQOL outcomes. Second, it is possible that engagement with the study facilitator, rather than the PP program, explains some of the observed improvements. Although the study facilitator did not engage with participants in completing the weekly exercises, the weekly calls may still have provided some benefit in the form of emotional support. Future studies should consider adding a weekly educational component, such as an informational email, for those in the waitlist control group. This could help to explain whether the observed improvements were a result of the PP intervention, contact with the study facilitator, or derived from a sense of self-efficacy from learning more about the disease. Third, this study was subject to self-selection bias, which may limit the external validity of the findings.26 Not all newly diagnosed people with MS approached about participation in this study agreed to participate. It is unclear whether those who agreed to participate were similar to those who declined participation in terms of baseline well-being. Fourth, at baseline, there were significant differences on PRO measures between participants in the intervention group and the waitlist control group. In all cases, participants in the waitlist control group reported better function. These differences may have impacted the efficacy analyses.
Newly diagnosed people with MS completed a 5-week, at-home, self-directed PP intervention as part of a phase 1 RCT. The results of the study support the feasibility, acceptability, and potential efficacy of the PP intervention designed to improve well-being in newly diagnosed people with MS. Larger trials with longer follow-up are needed to further investigate the benefits of PP training to improve adjustment to MS, leading to better psychosocial and health outcomes. Combined or multifocal interventions targeting multiple needs at the time of diagnosis, including informational and emotional support needs and social and physical needs, should also be considered
Financial Disclosures: Brian C. Healy, PhD, has received grants from Novartis and Genzyme. All other authors report no relevant disclosures.
Funding/Support: This study was supported by the Cynthia Brudnick MS Wellness Fund at the Brigham and Women’s Hospital.
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