Prospective associations of better quality of the diet with improved quality of life over 7.5 years in people with multiple sclerosis

BACKGROUND: There is increasing interest in the role of diet in multiple sclerosis (MS) progression and whether a healthier diet may lead to improved health and wellbeing in people living with MS (plwMS). OBJECTIVE: To assess the prospective relationship of the quality of dietary intakes with quality of life (QoL) in an international cohort of plwMS followed over 7.5 years. METHODS: Data from the Health Outcomes and Lifestyle In a Sample of people with Multiple sclerosis (HOLISM) cohort from baseline to 7.5-year review were analysed. Quality of the diet was assessed using the Diet Habits Questionnaire (DHQ). QoL was measured by the MSQOL-54, including physical and mental health composite scores and multiple subdomains. Linear regression was used to determine cross-sectional and prospective relationships with QoL, adjusted for clinical and demographic covariates. RESULTS: Amongst 948 participants, median physical- and mental-health QoL scores at 7.5-year review were 66.9 and 78.2, respectively. Baseline total DHQ was positively associated with subsequent change in physical-QoL to 7.5-year review, such that participants in the top two quartiles of baseline DHQ had 0.65 and 0.64 higher physical-QoL per year, though a similar association with mental-QoL did not persist on adjustment. Baseline meat consumption was associated with 0.38 lower physical-QoL per year, while baseline dairy consumption was associated with 0.50 and 0.41 lower physical- and mental-QoL per year, respectively. CONCLUSIONS: These results suggest efforts to improve the quality of dietary intake could be beneficial to the wellbeing of plwMS. Subject to replication, this aspect of lifestyle could be a useful intervention in better managing MS.