MG linked to lower quality of life, more use of medical care
Health-related quality-of-life study shows 'significant negative impact' of disease
People with myasthenia gravis (MG) experience a lower health-related quality-of-life impact, face a higher medical burden, and require more assistance from caregivers compared with the general population, according to data pulled from two international studies.
MG patients also were more likely to take sick leave from work and to use medical care, with more severe symptoms linked to further decline in their life quality.
“This direct comparison of people diagnosed with MG and the general population using two large international studies revealed significant negative impact of MG,” the researchers wrote. “Results were consistent across all outcomes, in all countries.”
The data were published in the journal Advances in Therapy under the title “People Diagnosed with Myasthenia Gravis have Lower health-related quality of life and Need More Medical and Caregiver Help in Comparison to the General Population: Analysis of Two Observational Studies.”
MG is driven by self-reactive antibodies that prevent muscle cells from effectively receiving messages from nerve cells, resulting in muscle weakness and fatigue.
In ocular MG, only the muscles around the eyes are affected. Most people with ocular MG eventually will develop generalized MG, a more severe form of the condition in which muscle weakness spreads throughout the body.
The affected muscles tend to become weaker after periods of activity and may not work as well until they are at rest. And in generalized MG, breathing, swallowing, and walking may become difficult, making it challenging to live life to the fullest, despite available treatments.
The MyRealWorld MG study
To better understand how MG affects health-related quality of life, a team led by researchers at Argenx and Services in Health Economics drew on data from the MyRealWorld MG study and the General Population Norms (POPUP) study.
Argenx is the developer of Vyvgart (efgartigimod alfa-fcab) and Vyvgart Hytrulo (efgartigimod alfa and hyaluronidase-qvfc), two injected therapies approved for adults with generalized MG.
MyRealWorld MG (NCT04176211) included 2,074 MG patients from nine countries who were living with the disease for an average of 9.3 years. For two years, they were asked to enter data about themselves and their disease on an app developed by Vitaccess.
More than half of the patients (53.4%) had both ocular and generalized MG, while the remaining patients had either generalized (35%) or ocular (11.6%) disease. Less than half (41.7%) experienced mild disease, whereas others experienced moderate (39.6%) or severe (18.7%) disease. Most (86.2%) were being treated for MG.
POPUP study used for comparison
The POPUP study included 9,000 people from the general population in eight countries, and their data were used for comparison.
Results showed that 55.9% of people with MG were able to live independently, compared with 70.5% of those in the general population. It also was more common for MG patients to live at home with help from a caregiver (6.4% vs. 3.1%).
MG patients scored significantly higher than the general population in the MG Activities of Daily Living (5.8 vs. 1.2 points), a patient-reported measure of disease severity in which higher scores indicate worse symptom burden.
Only 3.5% of the general population had symptom burden matching that experienced by people with moderate MG; for severe MG, it was only 2.9% of the general population.
“The POPUP respondents who had the symptom burden of moderate to severe MG were mostly younger males, living in the US and were in need of a caregiver,” the researchers wrote.
On a health status measure called EQ-VAS — with scores ranging from 0 (worst imaginable health) to 100 (best imaginable health) — people with MG rated their own health on average 14 points lower than the general population group (75.7 vs. 61.7 points).
Assessing health-related quality of life
Health-related quality of life also was measured with the EQ-5D-5L questionnaire, which covers five dimensions: mobility, self-care, usual activities, pain or discomfort, and anxiety or depression. Scores range from 0 (a state as bad as being dead) to 1 (full health).
MG patients scored significantly lower in the EQ-5D-5L than the general population (0.739 vs. 0.843). This significant difference was seen in all six countries with data from both populations, including the U.S. and Germany. The smallest difference was observed in Germany, and the largest in the U.S.
Moreover, EQ-5D-5L scores varied significantly across different levels of MG severity, showing a reduction from patients with mild disease (0.872) to those with moderate disease (0.707) and those with severe disease (0.511).
Similar observations were made for HUI3, another measure of current health status.
MG patients were about 2.5 times more likely to have taken a sick leave in the previous month relative to the general population (34.4% vs. 13.2%), and 3.5 times more likely not to work at all for health reasons (16.8% vs. 4.8%).
Roughly one-third (34.8%) of people with MG reported needing help from a caregiver to carry out daily activities, compared with 8.3% of the general population. They also were about twice as likely to have had any type of medical care visit in the previous month (51.9% vs. 24.6%).
These findings highlight a “considerable gap” in health-related quality of life for people with MG, the team wrote, adding that these patients “experience more problems in physical as well as mental health, in their activities of daily living, and in their social and working relationships.”
The disease has also “an economic impact as people diagnosed with MG utilize more medical resources, more often need a caregiver, and take more sick leave than members from the general population,” the researchers wrote.