Caregiver Burden and Value Assessments in Duchenne Muscular Dystrophy

As innovative treatments emerge for Duchenne muscular dystrophy (DMD), the complexities of caregiver burden are slowly coming into focus, revealing some of the complexities involved in assessing the value of new, life-extending interventions, according to a discussion during a recent webinar hosted by the International Society for Pharmacoeconomics and Outcomes Research (ISPOR).

Fleur Chandler

Erik Landfeldt, Ph.D., a senior epidemiologist at IQVIA in Stockholm, Sweden, and associate editor for the Journal of Neuromuscular Diseases, highlighted issues related to societal value and how these issues may influence future health technology assessments for DMD treatments. Fleur Chandler, a health economist and market access specialist, talked about the challenges of being a parent of a child with DMD.

DMD is a severe genetic disorder characterized by progressive weakness and degeneration, leading to loss of upper limb function and wheelchair dependency. Premature death ultimately results from respiratory failure or cardiac insufficiency. The disease is caused by a faulty DMD gene located on the X chromosome that is responsible for the production of dystrophin, a protein essential for normal muscle function. In the past several years, a number of new treatments have been approved for DMD, including antisense oligonucleotides, such as Vyondys 53 (golodirsen), Exondys 51 (eteplirsen), Amondys 45 (casimersen) and Viltepso (viltepso), and a gene therapy, Elevidys (delandistrogene moxeparvovec). Although DMD is a relatively rare disease, affecting approximately 1 in every 5,000 males, ages 5 to 9, according to the Centers for Disease Control and Prevention. Even so, the high cost of these new therapies means that payers are concerned about the cost of DMD treatment. The high financial stakes have also fueled interest in value assessment and cost-effectiveness research.

As discussed during the webinar, another factor in assessing DMD treatments is the variability in clinical outcomes. The course of the disease can differ greatly among affected individuals, making it difficult to establish a standardized set of metrics for evaluation. The lack of predictability also has an enormous impact on the health-related quality of life of the caregiver.

Chandler spoke about learning of her child’s diagnosis and the severe anguish that followed as her quality of life suffered, including her mental and physical health. She provided a detailed account of how the care for her son evolved, eventually leading to the need for three caregivers, all funded by social services. Fleur said her and other caregivers’ experiences are often overlooked costs in health technology assessments.

Landfeldt noted that health technology assessment groups and agencies in countries such as Canada and the U.S. have started recommending the inclusion of caregiver burden in their cost-effectiveness analyses. These agencies are recognizing the costs of care for DMD patients, such as worker absenteeism and loss of leisure time. From society’s perspective, there is an indirect productivity loss resulting from the caregiver's nonparticipation in paid work. He adds that economic evaluations incorporating indirect and informal care costs of caregivers would enhance the cost-effectiveness of the new treatment, assuming the therapy would reduce caregiver burden. On the other hand, any therapy that extends the life of a DMD patient may show a reduced cost-effectiveness because it would likely add to the cost of informal care. This relationship adds to the complexity of modeling cost effectiveness.