Physical Activity and Sedentary Behavior Patterns Across Weekdays and Weekend Days in Youth With Multiple Sclerosis and Controls.

Background: This study quantified and compared weekday and weekend patterns of device-measured physical activity (PA) and sedentary behavior between youth with pediatric multiple sclerosis (MS) and controls for the purpose of informing future PA behavior change interventions. Methods: Participant data were obtained from 3 ongoing observational studies, and the sample included 40 participants with pediatric MS and 41 controls. Light PA (LPA), moderate to vigorous PA (MVPA), and sedentary behavior data were collected using activity monitors (ActiGraph LLC) over 1 week. The main analysis involved a 2-way mixed factor analysis of variance with group as a between-subjects factor (pediatric MS vs control) and day as a within-subjects factor (weekday vs weekend day). Results: There was no group by day interaction from the analysis of variance for percentage of activity monitor wear time spent in LPA, MVPA, or sedentary behavior. There was no effect of group for LPA, MVPA, or sedentary behavior. There was an effect of day of week on percentage of day spent in LPA, MVPA, and sedentary behavior. Conclusions: These results suggest that youth with pediatric MS and controls were less physically active and more sedentary on weekends than on weekdays, but there were no differences between groups in PA and sedentary behavior overall or by day of the week. Physical activity interventions may be more successful by initially targeting weekend day activity.

Progressive retinal changes in pediatric multiple sclerosis.

Objectives To determine to what extent acute demyelinating episodes versus chronic degenerative phenomena drive retinal neuroaxonal damage in pediatric acquired demyelinating syndromes (ADS). Methods We acquired optical coherence tomography (OCT) data (follow-up range: 2 weeks - 5 years, at variable intervals from presentation) in pediatric participants who had multiple sclerosis (MS), monophasic ADS, or were healthy. Multivariable mixed effects models were used to assess the association of the number of demyelinating episodes (either optic neuritis [ON], or non-ON relapses) with changes in retinal nerve fiber layer (RNFL) or ganglion cell layer-inner plexiform layer (GCIPL) thickness. Results 64 OCT sans from 23 MS, and 33 scans from 12 monophasic ADS participants were compared with 68 scans from 62 healthy participants. The first ON episode had the biggest impact on RNFL or GCIPL thickness in monophasic ADS (RNFL: -7.9 µm, CI=5.5, p = 0.0056; GCIPL: -8.4 µm, CI=4.4, p = 0.0002) and MS (RNFL: -16 µm, CI = 3.7, p < 10-6; GCIPL: -15 µm, CI = 2.6, p < 10-6). Non-ON relapses were also associated with small but significant retinal thickness reductions in MS (RNFL: -2.6 µm/relapse, CI = 1.4, p = 0.0003; GCIPL: -2.8 µm/relapse, CI = 0.89, p < 10-6). MS participants showed progressive GCIPL thinning independent of acute demyelinating episodes (-2.7 µm/year, CI = 1.9, p = 0.0058). Conclusions We showed a prominent impact of early ON episodes on OCT measures of neuroaxonal structure in patients with ADS. We also demonstrated negative effects of non-ON relapses, and the presence of chronic retinal neurodegenerative changes, in youth with MS.

Physical Activity in Youth with Multiple Sclerosis receiving the ATOMIC intervention: Social connectedness above all else.

BACKGROUND: Within the pediatric MS population, physical activity (PA) has been associated with positive health outcomes such as lower lesion and relapse rates (Grover et. al., 2015). Recently, associations between variables from a social-cognitive theory (SCT) and levels of PA in youth with multiple sclerosis have been reported (Sikes & Motl, 2020), suggesting a SCT-based intervention may be efficacious in changing PA. We developed and delivered a 12-week SCT-based intervention and sought to gain an understanding of youth's perspectives on PA over time. METHODS: We performed a qualitative analysis on 34 coaching call transcripts from 13 participants as part of a theory-based intervention promoting PA in youth with MS (NCT03137602). Coaching calls were semi-structured and each participant was scheduled to have three coaching calls spaced monthly for three months. We used an inductive content analysis approach to analyze the data (Elo and Kyngas, 2008). RESULTS: General themes from the calls aligned with the SCT constructs. Youth consistently discussed facilitators for changing PA over time, including a positive attitude, goal setting and social connectedness. There was increasing conversation around PA barriers over time including the environment and a lack of time. CONCLUSION: Youth perceptions on PA can be either positive or negative and can change over time. There is an underlying emergence and importance of social connectedness within PA behaviours. Increases in coaching call content related to goal setting suggest a positive effect of coaching and SCT in these areas. Future studies will focus on interactions between SCT constructs, particularly social connectedness and increased physical activity.