Mastery is associated with greater physical and mental health-related quality of life in two international cohorts of people with multiple sclerosis

Background: Mastery is the sense of being in control of one's life and improvement in mastery may help to enhance quality of life. Little research has explored mastery in people with multiple sclerosis (MS), including its association with quality of life. Objective: To explore the association between mastery and health-related quality of life (HRQOL) in people with MS. Method: Two cross-sectional cohorts of adults with MS (n = 1401 and n = 573), recruited through convenience sampling, completed an online survey which measured mastery using the Pearlin Mastery Scale, physical and mental HRQOL via physical and mental health composite scores of MSQOL-54, along with other covariates, including demographics, clinical characteristics and lifestyle factors. Linear regression assessed associations between mastery and physical HRQOL adjusting for age, sex, education, disability and depression, and between mastery and mental HRQOL adjusting for age, sex, education, disability and clinically significant fatigue. Results: Greater mastery score was associated with higher physical and mental HRQOL in both cohorts, such that a one-point increase in the PMS was associated with an increase of 2.9 (95% Confidence Interval (CO: 2.6, 3.1) and 2.8 points (95% CI: 2.4, 3.2) in the means of physical HRQOL score in the first and second cohorts respectively, and a 2.9-point (95% CI: 2.7, 3.1) and 3.1-point (95% CI: 2.7, 3.4) increase in the means of mental HRQOL score. A dose-dependent relationship was demonstrated between a quartile categorical mastery variable and both physical and mental HRQOL in both cohorts. Mastery was associated with all subscores of both physical and mental HRQOL. Conclusions: Greater mastery is associated with better physical and mental quality of life. Efforts to improve the sense of self control and agency of people with MS may have benefits for their quality of life, even despite clinical features of the illness.