Health Related Quality of Life and Costs of Healthcare Utilization of Norwegian Myasthenia Gravis Patients

Abstract

Myasthenia Gravis is a chronic autoimmune disease that causes weakness in the skeletal muscles. It is a rare disease with a relatively small amount of knowledge about the patients’ quality of life. The objective of this study was to increase the knowledge regarding the Health-Related Quality of Life (HRQOL) of Norwegian Myasthenia Gravis (MG) patients, as well as evaluating the validity of the generic HRQOL measurement instrument EQ-5D-5L as a measurement of HRQOL for Norwegian MG patients. In addition approximate costs of the patients’ healthcare utilization due to MG was also calculated, in order to investigate the current costs associated with the disease. The study included 67 participants suffering from MG. The participants responded to the generic questionnaire EQ-5D-5L as well as the MG specific questionnaire Myasthenia Gravis Quality of Life 15 (MGQOL15). The mean HRQOL of 0.63 found for the whole sample was similar to levels of HRQOL in results of previous studies. Construct validity was tested for by comparing corresponding dimensions of HRQOL from the two questionnaires EQ-5D-5L and MGQOL15, and observing whether the resulting correlation ρ > 0.4. Most of the corresponding dimensions were found to satisfy this condition, however with many items of the MGQOL15 having no corresponding dimensions in the EQ-5D-5L, care should be taken when using only this questionnaire to study the HRQOL of MG patients. A mapping analysis was performed to make HRQOL estimations from the data of the MGQOL15 questionnaire. Due to restrictions regarding gathering of health data, possibly relevant health information was not gathered and available for the analysis. The selection of the sample population was considered to have a high risk of bias. Studies with better access to the an unbiased sample of patients could provide conclusions with more generalizable results.