Determinants of health-related quality of life in multiple sclerosis: The role of illness intrusiveness and self-complexity

Multiple sclerosis (MS) is a common demyelinating chronic illness that primarily affects young adults. It is characterized by its progressive and unpredictable nature, and poses many physiological and psychological challenges to both the individual and the family. An area of recent research interest has involved examining the impact of MS on health-related quality of life (HRQL). HRQL facilitates study of the effectiveness of a treatment not only from a medical or physiological perspective, but also from social, psychological, and economic vantage points. While it is clear that MS has an adverse impact on HRQL, it is not clear what accounts for this relationship. This study was focused on clarifying the relationship between MS and HRQL by investigating how illness intrusiveness and self-complexity may play intermediary roles between the impact of MS and HRQL. Participants were recruited from the Medical Rehabilitation Research and Training Center for Multiple Sclerosis at Saint Agnes Hospital in White Plains, New York, an affiliate of New York Medical College and included 90 individuals with MS. They completed brief neuropsychological measures and self-report questionnaires measuring HRQL, psychological adjustment, illness intrusiveness, and self-complexity. Results indicated that physical aspects of HRQL, both generic and MS-specific, were significantly predicted by disease severity, whereas mental and emotional aspects of HRQL were predicted by information processing speed. Depression and well-being were predicted by disease severity and information processing speed. The extent to which individuals viewed the MS as intrusive mediated the manner in which disease severity predicted each of the following: physical HRQL, fatigue, and depression. Self-complexity only interacted with upper extremity function to predict illness intrusiveness, but opposite to the predicted direction. Those with greater physical disability and higher self-complexity actually experienced more illness intrusiveness. Implications of the current research underscore the need for broader scopes of assessing MS and its impact on the individual. The data also serve in supporting the use of HRQL as it is broadly defined in assessing outcome in chronic illness. While in most cases physical indices of disease predict physical quality of life and cognitive assessments predict mental and emotional quality of life, the individual\u27s perception of MS is a major determinant of adjustment. This points to the need for psychological intervention in helping individuals adapt to MS