Multiple sclerosis is a neurological disease of the central nervous system characterized by micro- and macroscopic areas of demyelination. The onset is primarily between the ages of 20 and 45 years with a wide spectrum of symptoms and signs [1
]. There are ubiquitous reports in the literature on the extent of disability as result of being affected by the disease [4
]. Patients with multiple sclerosis may suffer from visual symptoms, decreased cognitive function, pain, depression, gait ataxia, bladder and sexual dysfunction, and last but not least vocal and speech disorders. All of these symptoms may result in social and physical impairment. Different questionnaires such as the expanded disability status scale for disability status (EDSS), the Hamilton rating scale for depression and fatigue severity scale (FSS) for extent of fatigue have been used to stage the disease and assess the extent of disability and impairment [9
]. Despite the redundancy in research on the concepts of impairment and disability in MS patients in relation to the various systems in the body, less emphasis has been put on the impact of these disabilities and impairments on quality of life.
Quality of life is defined as “the individual's perceptions of their position in life in the context of culture and value system in which they live, and in relation to their goals, expectations, standards and concerns” as defined by the WHO [12
]. Health-related quality of life is conceptualized on those aspects of life quality or function which are influenced by health status. There are several health related quality of life instruments, and these include the generic ones and the disease-specific instruments. The generic measures have been developed without a specific disease in mind whereas the MS-specific health related quality of life is disease specific and includes the Multiple Sclerosis Quality of Life-54, the Disability and Impact Profile, the Multiple sclerosis Impact scale, and the Hamburg Quality of Life Questionnaire in Multiple Sclerosis [5
Assessment of health related quality of life in patients with MS is important not only in research but also in clinical practice because it allows better decision making in the management and care policy in this group of patients. Several studies have reviewed the impact of multiple sclerosis on health related quality of life in relation to pain symptoms, cognitive function, depression, fatigue, disability, effect of medications, and others [4
]. Based on an extensive literature review, using the words multiple sclerosis and voice, the authors of this paper could not identify a study that examines voice-related quality of life in patients with multiple sclerosis except for one study by Chiara et al. on the effect of expiratory muscle strength on voice production and voice related quality of life [14
]. The study was limited by the small number of subjects with only seventeen participants, 5 of whom withdrew secondary to exacerbation of their expanded disability status scale. Assessment of voice related quality of life not only allows new therapeutic interventions but also may result in a change in the care of policy of affected patients.
The purpose of this study is to investigate the voice related quality of life in a large group of patients with multiple sclerosis. The Voice Handicap Index, one of many patient-reported outcome measures that have gained popularity in both the clinical and research milieus, will be used in this investigation.