Health-related quality of life and health literacy in patients with systemic mastocytosis and mast cell activation syndrome.

Background: Systemic mastocytosis is a rare genetic disease characterized by aberrant proliferation and/or activation of mast cells, resulting in multi-organ, allergy-like symptoms. Mast cell activation syndrome (MCAS) is a clinically similar, but more prevalent disease with unclear etiology. In this study, the health-related quality of life (HRQOL) and health literacy of people suffering from SM and MCAS were assessed.

Results: Two validated questionnaires (QLQ-C30/QLQ-INFO25) from the European Organisation for Research and Treatment of Cancer (EORTC) were used to analyze HRQOL and level of information of SM and MCAS patients. In addition, a control group without any health issues was included. Data were analyzed by ANOVA and linear regression to detect significant differences. Questionnaire data from 66 patients with MCAS (83% female, mean 44 years), 32 patients with SM (78% female, mean 53 years) and 52 healthy participants (67% female, mean 48 years) resident in Germany were analyzed. HRQOL as measured by the Global health status was significantly worse in patients suffering from MCAS or SM compared to control group. Individuals with MCAS showed a slightly, but insignificantly lower score on Global health status, and a significantly lower score with respect to role function and fatigue. Patients with the rare disease SM felt significantly better informed on their disease compared to MCAS patients. Linear regression performed separately for both groups showed a direct influence of the level of information on patients' HRQOL.

Conclusion: Overall, our study showed a significant negative impact on the HRQOL of both diseases, but only a small difference in quality of life and severity of symptoms between patients with MCAS and the supposedly more severe form, the rare disease SM. Our results demonstrate that the level of information patients receive impacts HRQOL, and that this is not only an issue in rare diseases, but also diseases with unclear etiology and pathology. Our data shows that even slight improvements in the patient's level of information can have a positive effect on their quality of life, further highlighting the importance of gaining more knowledge on rare and incompletely understood diseases and communicating these insights to patients.