Do higher levels of uncertainty in illness reduce the perceived health-related quality of life of Multiple Sclerosis (MS) patients?

Background: Multiple Sclerosis (MS) represents one of the most common causes of neurological disability and the unpredictability and severity of its manifestations determine uncertainty in illness. While MS patients’ Health Related Quality of Life (HRQoL) has been frequently assessed, the impact of uncertainty on HRQoL has not been adequately considered to date. The objective of the study was to help reduce this gap in the literature.Design: One hundred and twenty patients with relapsing-remitting MS were interviewed in order to gather information about their assessment of HRQoL, measured with the Visual Analogue Scale (VAS) and their perceptions of uncertainty in illness assessed through the Mishel Uncertainty in Illness Scale (MUIS). The relationship between HRQoL and two dimensions of uncertainty, namely “ambiguity” and “inconsistency”, have been tested with diverse Tobit and Probit specifications.Results: Inconsistency exhibited a negative and significant correlation in all the specifications of the model. Marginal effects suggested how a unit change in the total score of the inconsistency scale determined an increase of 6.2% in the probability to report a VAS score higher than 60 (median score in the sample). Ambiguity and inconsistency, jointly considered, had a marginal effect of 2.1%.Conclusions: This study contributes to the assessment of the patient’s general status over the standard parameters for quality of life. It may represent the starting point for further analyses on the impact of separate facets of the Uncertainty in Illness on HRQoL, experienced not only by MS patients, but also by other patients suffering from chronic conditions.