J Clin Neurol.  2019 Jul;15(3):376-385. 10.3988/jcn.2019.15.3.376.

Examining the Impact of Refractory Myasthenia Gravis on Healthcare Resource Utilization in the United States: Analysis of a Myasthenia Gravis Foundation of America Patient Registry Sample

• Xin H
• Harris LA
• Aban IB
• Cutter G

• KMID: 2451123
• DOI: http://doi.org/10.3988/jcn.2019.15.3.376

Abstract

BACKGROUND AND PURPOSE
Patients with refractory myasthenia gravis (MG) experience ongoing disease burden that might be reflected in their healthcare utilization. Here we examine the impact of refractory MG on healthcare utilization.
METHODS
The 825 included participants were aged 18-64 years, enrolled in the Myasthenia Gravis Foundation of America Patient Registry between July 2013 and February 2018, and had been diagnosed with MG ≥2 years previously.
RESULTS
Participants comprised 76 (9.2%) with refractory MG and 749 (90.8%) with nonrefractory MG. During the 6 months before enrollment, participants with refractory MG were significantly more likely than those with nonrefractory MG to have experienced at least one exacerbation [67.1% vs. 52.0%, respectively, p=0.01; odds ratio (OR)=1.882, 95% confidence interval (CI)=1.141-3.104], visited an emergency room at least once [43.4% vs. 27.1%, p<0.01; OR=2.065, 95% CI=1.276-3.343], been hospitalized overnight at least once (32.9% vs. 20.5%, p=0.01; OR=1.900, 95% CI=1.140-3.165), ever been admitted to an intensive care unit (ICU) (61.8% vs. 33.4%, p<0.01; OR=3.233, 95% CI=1.985-5.266), or ever required a feeding tube (21.1% vs. 9.1%, p<0.01; OR=2.671, 95% CI=1.457-4.896). A total of 75.8% younger females with refractory disease (<51 years, n=33) experienced at least one exacerbation, 69.7% had been admitted to an ICU, and 30.3% had required a feeding tube. For older females with refractory disease (≥51 years, n=33), 60.6%, 54.6%, and 6.1% experienced these outcomes, respectively (between-group differences were not significant).
CONCLUSIONS
Refractory MG is associated with higher disease burden and healthcare utilization than nonrefractory MG.

Keyword

myasthenia gravis; refractory disease; disease exacerbations; healthcare resource utilization

MeSH Terms

Americas*
Delivery of Health Care*
Emergency Service, Hospital
Female
Humans
Intensive Care Units
Myasthenia Gravis*
Odds Ratio
United States*

Figure

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  Fig. 1 Criteria used for classifying refractory MG. MG-ADL: myasthenia gravis activities of daily living scale.

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  Fig. 2 Flow chart showing selection process for the study sample. MG-ADL: myasthenia gravis activities of daily living scale.

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  Fig. 3 Exacerbations in and healthcare resource utilization by participants with refractory MG and nonrefractory MG (A) and numbers of exacerbations and ER visits during the 6 months before enrollment in participants with refractory and nonrefractory MG (B). Frequencies of study variables were compared between participants with refractory and nonrefractory MG using χ2 tests for categorical variables and the number of exacerbations, and Fisher's exact test for the number of ER visits. p values are for comparisons between the refractory- and nonrefractory-MG groups, and were calculated after excluding data from participants with unknown/missing data. *During the 6 months before enrollment. ER: emergency room, ICU: intensive care unit, MG: myasthenia gravis.

• 

  Fig. 4 Unadjusted ordinal logistic model examining the impact of refractory MG on exacerbations and healthcare resource utilization. *During the 6 months before enrollment. Analyses were based on fitting logistic models for binary outcomes except for when analyzing the numbers of exacerbations and ER visits, for which proportional-odds models for ordinal outcomes were fitted. CI: confidence interval, ER: emergency room, ICU: intensive care unit, MG: myasthenia gravis, OR: odds ratio.

• 

  Fig. 5 Exacerbations in and healthcare resource utilization by younger and older female participants with refractory MG (A) and numbers of exacerbations and ER visits during the 6 months before enrollment in younger and older female participants with refractory MG (B). Frequencies of study variables were compared between participants with refractory and nonrefractory MG using χ2 tests for categorical variables and the number of exacerbations, and using Fisher's exact test for the number of ER visits. p values are for comparisons between the refractory- and nonrefractory-MG groups, and were calculated after excluding data from participants with unknown/missing data. *During the 6 months before enrollment. ER: emergency room, ICU: intensive care unit, MG: myasthenia gravis.

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