Systemic mastocytosis and mast cell activation syndrome both negatively impact health-related quality of life (HRQOL), with mast cell activation syndrome patients reporting more significant impacts on everyday life.
Systemic mastocytosis (SM) and mast cell activation syndrome (MCAS)—both mast cell activation diseases (MCADs)—lack research regarding the patient experience. A study published in Orphanet Journal of Rare Diseases aimed to fill this knowledge gap by surveying patients on the effects SM and MCAS have on health-related quality of life (HRQOL).
SM is rare and is characterized by abnormal mast cell proliferation or activation, leading to systemic allergy-like symptoms. The clinical presentation of SM varies, and confirmatory bone marrow biopsy is needed for diagnosis. It ranges from mild to severe, with prognosis varying from normal life expectancy to a few years or months. MCAS, which has clinical characteristics similar to SM, is more common but has unclear etiology and pathology. Symptoms of both conditions can include flushing, itching, abdominal cramps, nausea and vomiting, and general pain.
Although some previously published data show that SM has a negative impact on HRQOL, data are not available for MCAS. The study authors expected MCAS to have a similar impact, with variations due to the heterogenous nature of MCAS presentation. Their study used 2 validated questionnaires, the European Organization for Research and Treatment of Cancer QLQ-C30 and QLQ-INFO25 to explore the HRQOL and health literacy of SM and MCAS patients.
“It was of particular interest to investigate whether fatigue, which is known to have a major impact on quality of life and activities of daily living in a vast spectrum of chronic diseases such as cancer, end-stage renal, liver, or lung diseases, as well as CNS [central nervous system] pathologies and many others, would also be a more consistent factor in SM compared to MCAS,” the study authors wrote.
Questionnaires from 66 patients with MCAS, 32 patients with SM, and 52 healthy controls were included in the study. As far as overall health status, there were significant differences between the control cohort and the 2 mast cell diseases.
Six functional areas were assessed with the QLQ-C30: global health, physical function, role function, emotional function, cognitive function, and social function. Various symptoms, including fatigue, were also examined via the QLQ-C30. Individuals in the control group reported significantly better global health than the MCAS and SM groups, confirming the assumed impact on HRQOL these conditions have. There were no significant differences between the MCAS and SM groups regarding global health status, but those with MCAS did report a slightly lower global health score.
Similar results were seen with disease symptoms. Patients with either of the 2 MCADs reported experiencing significant symptoms, including fatigue. Compared with the control group, patients with MCAS or SM experienced significantly lower HRQOL based on the reported symptoms. Patients with MCAS were moderately more prone to fatigue than patients with SM, which was an unexpected outcome.
Health literacy in patients with MCAS and SM, which is largely the attending physician’s responsibility, was assessed with the QLQ-INFO25. In 99% of cases, patients reported wanting to receive more information about their conditions, such as causes, possible inheritance, and treatment options. Those with MCAS were less informed about their disease overall than patients with SM. Patients with SM were also more satisfied with the level of information they received from physicians. A linear regression model showed that health literacy had a positive impact on HRQOL.
“As previously hypothesized, we expected a correlation between health literacy and quality of life, which was especially interesting in light of the better performance of the SM group on the QLQ-INFO25 and the overall slightly better performance on the QLQ-C30, as an effect caused by health literacy could be a possible explanation,” the authors wrote.
Overall, the study showed that SM and MCAS negatively impact HRQOL for patients, with those who have MCAS reporting a more significant impact on everyday life. Individuals with SM were typically more informed about their disease, which was associated with higher levels of satisfaction and positively impacted HRQOL.
“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,” the authors wrote. “Our data show 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.”
Schmidt TJ, Sellin J, Molderings GJ, Conrad R, Mücke M. Health-related quality of life and health literacy in patients with systemic mastocytosis and mast cell activation syndrome. Orphanet J Rare Dis. Published online July 29, 2022. doi:10.1186/s13023-022-02439-x