Patient-Reported Outcomes in Myotonic Dystrophy Type 2: Correlations with Motor and Cognitive Endpoints
Nikita Jain1, Carly Jo Olszewski3, Laura Flashman1, Carolina Burgos-Aguilar2, Pamela Duncan1, Peggy Nopoulos4, Araya Puwanant1
1Neurology, Wake Forest School of Medicine, 2Wake Forest School of Medicine, 3Neurology, Hawaii Residency Programs, 4Psychiatry, University of Iowa Health Care
Objective:
To characterize patient-reported outcomes (PROs) and evaluate relationships between PROs and clinical endpoints in patients with myotonic dystrophy type 2 (DM2).
Background:
Although muscle weakness is the key feature in DM2, two-thirds of patients report that impaired cognition is among the most disabling symptoms and affects their quality of life. PROs of physical and mental status are extremely limited in DM2 but could serve as measures for clinical trial development.
Design/Methods:
Ten individuals with DM2 and ten age and gender-matched controls were enrolled. All participants underwent brain MRIs and a comprehensive battery of cognitive and motor measures. Additionally, they completed PROs, including the 36-Item Short Form (SF-36), PRO Measurement Information System (PROMIS-10), Beck Depression and Anxiety Inventory (BDI and BAI), and Apathy Evaluation Scale (AES). Paired t-test and Spearman’s correlation were used to determine group differences and correlations between PROs and clinical endpoints.
Results:
Of 20 participants (60% female), mean age and education were similar between groups. Compared to controls, the DM2 group showed a significant difference in BAI, AES, and SF-36 physical functioning (PF) subscale (p=0.004-0.024) and impaired PROMIS-Global Physical (GPH) and Mental Health (GMH). We found a strong correlation between SF-36 (PF) and PROMIS-GPH with a 6-minute walk test and gait speed (rho=0.68-0.75, p=0.02-0.04). Moderate correlations were observed between 1) BDI and verbal fluency test; 2) BAI and processing speed; 3) AES and a test of executive function and cerebral white matter integrity.
Conclusions:
Our pilot study demonstrates that changes in mental and physical health status are of significance for DM2 patient's quality of life. The relationships between PROs (BAI, BDI, and AES) and cognitive endpoints suggest brain involvement. PROs, as measured by SF-36 and PROMIS-10, are associated with motor endpoints. These results support the use of PROs as a tool to measure disease burden in DM2.