A retrospective analysis of health care utilization for patients with mitochondrial disease in the United States: 2008-2015.

BACKGROUND: Mitochondrial disease (MD) is a heterogeneous group of disorders characterized by impaired energy production caused by abnormal oxidative phosphorylation. Diagnosis of MD is challenging given the variability in how the disease can affect an individual's neurologic, cardiovascular, ophthalmologic, or gastroenterological systems. This study describes the health care utilization and cost in patients diagnosed with MD.

METHODS: This study was a retrospective claims analysis based on data from the Truven Health Analytics MarketScan Database and Milliman's Consolidated Health Cost Guidelines Sources Database. For the purpose of this study the diagnosis of MD was defined by ICD-9-CM (prior to October 2015), and ICD-10-CM (October 2015 or later), and included patients identified between January 1, 2008 to December 31, 2015. ICD-9-CM code of 277.87 (disorders of mitochondrial metabolism) and the ICD-10-CM codes of E88.40, E88.41, E88.42 and E88.49 (mitochondrial metabolism disorders) were used as inclusive criteria. Patients were included if they had at least six months of exposure after the first MD-related claim occurrence, and either one MD claim in the inpatient setting OR two MD claims in an outpatient setting. Claims of MD patients are compared to those of a general insured total member population, as well as to those from multiple sclerosis (MS) and amyotrophic lateral sclerosis (ALS) patients.

RESULTS: During the study period, 3825 patients between the ages of 0 and 15 (pediatric) and 4358 patients 16 years of age and greater (adult) were identified. Total allowed per member per month (PMPM) cost for pediatric patients was $4829 and $3100 for adults, compared with an average of $202 and $486, respectively, for the total member population. The greatest drivers of costs based on allowed claims came from inpatient, surgery, and prescription medications. In the adult population, MD imposes a PMPM cost burden that was comparable to that observed for multiple sclerosis ($3518) and ALS ($3460) patients.

CONCLUSIONS: This retrospective claim study highlights the significant differences in the cost of medical care for MD patients compared to those of a general population. Mitochondrial disorders are associated with multisystem disease manifestations and a greater care and cost burden similar to other devastating neuromuscular diseases.