Costs and health resource use in patients with X-linked myotubular myopathy: insights from U.S. commercial claims

Abstract

BACKGROUND: In X-linked myotubular myopathy (XLMTM), mutations in the MTM1 gene result in absence or dysfunction of myotubularin, a protein required for normal development, maintenance, and function of skeletal muscle. Extreme muscle weakness results in severe respiratory failure that is fatal for approximately half of XLMTM-affected children by age 18 months.Most surviving patients require invasive mechanical ventilation, feeding tubes, and wheelchairs for mobility, due to profoundly impaired motor function. Little is known about the costs of care for this rare disease. Currently, there are no approved therapies for XLMTM. OBJECTIVE:To quantify the direct medical costs and health care resource utilization (HRU) incurred by XLMTM patients and paid by commercial insurers. METHODS:A retrospective, longitudinal study was conducted using the IQVIA PharMetrics Plus commercial database of adjudicated claims for more than 140 million individuals with commercial insurance coverage in the United States. An algorithm based on demographic information, diagnosis and procedure codes, and medications was used to identify XLMTM patients younger than aged 2 years during the study period from January 1, 2006, through September 30, 2018. All-cause direct medical costs and HRU during each month were calculated. Costs were grouped as inpatient hospitalWhat is already known about this subject• Most children with X-linked myotubular myopathy (XLMTM) depend on permanent use of mechanical ventilation, feeding tubes, and wheelchairs.• The current costs of care for this rare disease have not been quantified. What this study adds• This is the first study that has attempted to quantify the economic burden of XLMTM in the United States and has found that annualized all-cause medical costs per patient totaled $897,978 in the first year of life and nearly $1.5 million total for patients who survived the first 4 years of life.• This study supports the value of potential future treatment options for XLMTM and could inform the collection of economic impact evidence for other rare genetic diseases.

Real-world analysis of healthcare resource utilization by patients with X-linked myotubular myopathy (XLMTM) in the United States

“…First hospitalization between 0 and 4 years of age for 80% of patients in our study supports Sack et al’s estimate of mean monthly per patient direct medical costs being highest in the first year of life ($74,831), with declining costs over the second, third, and fourth years of life ($23,207, $13,044, and $9,440, respectively) [ 11 ]. In addition, inpatient admissions ($69,025) accounted for the majority of the mean monthly per patient direct medical costs [ 11 ]. Both studies identified the major burden of ventilator support and ventilation management.…”

“…Our claims analysis expands on the findings from an economic analysis by Sacks et al showing very high medical costs and intense healthcare resource utilization associated with caring for patients with XLMTM [ 11 ]. First hospitalization between 0 and 4 years of age for 80% of patients in our study supports Sack et al’s estimate of mean monthly per patient direct medical costs being highest in the first year of life ($74,831), with declining costs over the second, third, and fourth years of life ($23,207, $13,044, and $9,440, respectively) [ 11 ]. In addition, inpatient admissions ($69,025) accounted for the majority of the mean monthly per patient direct medical costs [ 11 ].…”

“…4 ) were those often used to treat respiratory illness and infection, including albuterol (38%), amoxicillin-clavulanate (32%), fluticasone propionate (31%), and amoxicillin (30%). The most frequently used diagnosis and procedure codes (Table 3 ), however, were for investigation of various cholestatic and liver abnormalities, including, gamma-glutamyl transferase [ 25 ]; abnormal serum enzyme; other or unspecified [ 21 ]; jaundice [ 17 ]; elevation of aspartate aminotransferase (AST), alanine aminotransferase (ALT), or lactate dehydrogenase (LDH) [ 12 ]; obstruction of gallbladder or bile duct [ 11 ]; and cholelithiasis [ 10 ]. Abnormal living function/imaging was present in 16 (8%) patients, disorders of bilirubin metabolism in 9 (5%) patients, and the combination of abnormal serum enzyme levels and disorders of bilirubin metabolism in 27 (14%) patients.…”

“…Moreover, our study quantified the extensive use of tracheostomy, gastrostomy tube feeding, wheelchairs, occupational and physical therapy, and home care services. The Sacks et al analysis estimated the mean monthly per patient prescription medication cost at $540 [ 11 ] and we have shown that the most common medications prescribed for these patients are medications for respiratory illnesses and infections.…”

“…Multisystem disease involvement means that management and care of XLMTM is broad and complex and diagnosis, established or confirmed by genetic testing, can involve numerous diagnostic procedures and extensive healthcare resource utilization. Direct medical costs and health care resource utilization for children with XLMTM were recently estimated at $897,978 per patient in the first year of life and nearly $1.5 million total for patients who survive the first 4 years [ 11 ] .…”