Financial Burden of SMA Much Higher Than Other Conditions, Analysis Shows

Direct medical costs associated with spinal muscular atrophy (SMA) are more than 50 times higher than those of matched control patients without SMA, according to a healthcare claims analysis.

The primary driver of cost for infantile SMA cases was inpatient expenses, primarily for respiratory illnesses, while for child and juvenile cases, outpatient costs dominated, mostly for outpatient home care. 

In the analysis, titled “Economic burden of spinal muscular atrophy: an analysis of claims data” and published in the Journal of Market Access & Health Policy, the authors recommended the adoption and implementation of standardized care to lower costs.

Until recently, there were no effective treatments for SMA, and standard care included neurological and breathing support, nutritional requirements, specialized equipment, and physical and occupational therapy.

New disease-modifying therapies have been shown to significantly improve outcomes for people with SMA. As newer medicines continue to become available, SMA’s economic impact on patients and the healthcare system is still unclear, because financial data are limited.

To understand this impact, data analysis on the economic burden of SMA is needed, which will allow investigators to track changes related to cost as new treatments become available and may be used “to inform cost-effectiveness analyses and payer policy decisions related to the use of novel therapies,” the researchers wrote.

To fill this need, researchers at Cure SMA, in collaboration with colleagues at Novartis Gene Therapies (formerly AveXis), analyzed healthcare claims databases to assess the costs for SMA management during the four years prior to the approval of the first SMA disease-modifying therapy — Spinraza (nusinersen) — in a group of commercially insured patients.

Claims data were extracted from the Truven Health Analytics MarketScan Commercial Claims and Encounters and Medicare Supplemental databases between Oct. 1, 2012, and Dec. 31, 2016.

Patients eligible for the study had at least two SMA medical claims 30 or more days apart. As a control group, the same number of patients without SMA were included who were matched by birth year, gender, and geographic region. 

Of the SMA patients eligible, 58 had infantile SMA (diagnosed at younger than 1 year of age), 56 had child SMA (diagnosed at 1–3 years old), and 279 were diagnosed with juvenile SMA (3–18 years old). 

The infantile SMA analysis revealed that inpatient claims were significantly more common for patients (60.3%) than in controls (1.7%), with a mean of 1.3 inpatient admissions per person per year, versus 0.01 for controls. 

While one control participant had a one-day inpatient hospital stay, the mean length of each hospital stay for SMA infants was 10 days. Respiratory illness was the most common reason for inpatient admission among SMA infants, occurring in 24 of 35. The single control patient was also admitted due to a respiratory illness.

The mean annualized total net payments for inpatient SMA infant admissions was $118,609, compared with $59 for controls (based on one control patient), which was the “primary cost driver for infantile SMA,” according to the researchers. 

As for outpatients claims, the mean number of outpatient claims per person per year was 234.4 for SMA cases and 25.8 for controls, with mean net payments of $55,538 for SMA cases, compared with $2,047 for controls. Here, the most common type of outpatient claim was home health service, such as in-home skilled nursing or physical therapy.

Like infantile SMA, inpatient claims were significantly more common for child SMA cases (35.7%) than controls (3.6%), with a mean number of inpatient admissions per person per year of 0.62 for SMA children vs. 0.04 for controls. 

The mean annualized total net inpatient payments for child SMA cases was $26,940 vs. $144 for control cases, which was “more than 180-fold higher.” Again, respiratory illness was the most common reason for admission, occurring in 17 of 20. 

The outpatient claims per person per year was a mean of 248.7 for SMA cases vs. 16.9 for controls, with mean net payments for outpatient services of $73,094 compared with $1,308 for controls, which was “more than 50-fold higher for child SMA cases.” Among child SMA cases, a home health service was the most common type of outpatient claim. 

Consistent with the infantile and child SMA analyses, inpatient claims were significantly more common for juvenile SMA cases (47%) compared with controls (4.3%), with a mean number of inpatient admissions per person per year of 0.66 for SMA cases compared with 0.02 for controls. 

The mean length of each hospital stay was 5.8 days for juvenile SMA cases and 4.4 days for controls, and the mean annualized inpatients payments were $39,390 for SMA cases and $701 for controls, again, “more than 50-fold higher.” Respiratory illness was the most common reason for admission. 

Outpatient claims per person per year in juvenile cases was a mean of 170.3 compared with 12.2 for controls, with mean net payments of $49,068 vs. $1,135. Among these individuals, a home health service was the most common type of claim.

“Results of these analyses show that the economic burden of direct inpatient and outpatient costs associate with untreated SMA is tremendous and significantly higher than for age-, gender-, and region-matched controls,” the researchers wrote. “[This] analysis showed that costs are highest for patients with infantile SMA, the most severe form of the disease.”

“Uniform adoption and implementation of the current standards of care guidelines could result in fewer complications of SMA,” they added. “In addition, the availability of new treatments and widespread SMA newborn screening has the potential to not only reduce the economic burden of SMA but also to significantly improve long-term clinical outcomes and patient and caregiver quality of life.” 

They also pointed out that, according to a previous report, caregivers for children with rare diseases “spend an average of 53 hours per week on caregiving responsibilities,” which led to more than half of them cutting back on work hours, leading to lost wages and financial hardship.