Objectives were three-fold: 1) To quantifiably understand clinical meaningfulness in teens and young adults with Spinal Muscular Atrophy (SMA), 2) To help inform clinical trials’ design targeting teens and young adults, and 3) To collect information to better understand this population in order to develop resources.

With the approval of two treatments for SMA and several promising therapies on the horizon, it is hypothesized that the SMA teen and young adult populations will grow in the coming years. As such, there is a need to further understand this community, and better define what this population considers to be clinically meaningful in a given therapeutic. A better understanding of this will allow us to optimize outcome measures used in clinic and clinical trials and provide resources to support this population.

The SMA Health Index (SMA-HI), an instrument developed by Dr. Chad Heatwole at the University of Rochester, was the main instrument used to assess clinical meaningfulness among respondents. The instrument measures a patient’s perception of their multifactorial disease burden and is a reliable and valid mechanism to measure patient changes during clinical trials. Teenagers and young adults with SMA completed an electronic survey that included the SMA-HI and an open-ended supplement focused on schooling and socialization.

A total of 87 affected individuals ages 12-25 completed the survey. There were statistically significant differences in SMA-HI scores based on SMA Type, motor function level at time of survey, maximum motor function at time of diagnosis, and age. In addition, participants identified peer-support groups as a clear area of need in this population.

Disease burden profiles are unique in SMA teens and young adults and very with age and other demographic features. Moving forward it is worthwhile to better understand these patients and how their clinical phenotype differs from both child and adult populations.