Economic burden of generalized myasthenia gravis (MG) in the United States and the impact of common comorbidities and acute MG-events.

ABSTRACT

BACKGROUND: This study assessed the incremental healthcare costs and resource utilization (HRU) associated with generalized myasthenia gravis (gMG), as well as variability in these outcomes among patients with gMG and common comorbidities and acute MG-related events. METHODS: Adults with gMG and without MG were identified from a large US database (2017-2021). The index date was the first MG diagnosis (gMG cohort) or random date (non-MG cohort). Cohorts were propensity score matched 11. The gMG cohort included subgroups of patients with a 12-month pre-index (baseline) cardiometabolic or psychiatric comorbidity, or a post-index MG exacerbation/crisis. Monthly healthcare costs (2021 USD) and HRU were compared post-index between gMG and non-MG cohorts. RESULTS: The gMG and matched non-MG cohorts each contained 2,739 patients. Mean incremental healthcare costs associated with MG were $4,155 (gMG $5,567; non-MG $1,411), with differences driven by incremental inpatient costs of $2,166 (gMG $2,617; non-MG $452); all p < 0.001. The gMG versus non-MG cohort had 4.36 times more inpatient admissions and 2.26 times more outpatient visits; all p < 0.001. Among patients with gMG in cardiometabolic (n = 1,859), psychiatric (n = 1,308), and exacerbation/crisis (n = 419) subgroups, mean monthly healthcare costs were $6,660, $7,443, and $17,330, respectively. CONCLUSIONS: gMG is associated with substantial incremental costs and HRU, with inpatient costs driving the total incremental costs. Costs increased by 20% and 34% among patients with cardiometabolic and psychiatric conditions, respectively, and over three times among those with acute MG-related events. gMG is a complex disease requiring management of comorbidities and treatment options that can prevent acute symptomatic events.

Generalized myasthenia gravis (gMG) is a rare long-standing condition that affects the junctions between nerves and muscles, causing them to be weak. In a serious case, the diaphragm ­ a muscle that helps with breathing ­ becomes so weak that a patient will need a machine to breathe for them. This is called MG exacerbation or crisis. In this study, we used a large insurance database in the United States to look at how much money healthcare payers paid for gMG patients on average and what healthcare resources patients with gMG used. We compared these findings with patients without gMG. Also, among patients with gMG, we reported these findings specifically for patients who also had heart, blood, or blood vessel disease; patients who had a mental illness; and patients who had MG exacerbation or crisis later on. We found that patients with gMG used $5,567 per month on average ($4,155 more than patients without gMG), mostly from overnight hospital stays. Patients with gMG also had four times more overnight hospital stays and two times more hospital day visits when we compared them to patients without gMG. Patients with gMG and other health conditions used even more money and resources per month. Patients with MG exacerbation or crisis used $17,330 per month on average. Our results showed that gMG led to higher healthcare cost and resource use. In order to reduce cost and resources, doctors also need to control for other health conditions as they treat patients with gMG, and to prevent patients from having MG exacerbation or crisis later on.