Correlations of disease severity outcome measures in inclusion body myositis.

This study aimed to evaluate the correlation between various outcome measures used to assess disease severity and progression in inclusion body myositis (IBM) clinical trials. A cross-sectional study, involving 51 IBM patients meeting the European Neuromuscular Center (ENMC) 2011 criteria for clinically defined or probable IBM, was completed at the University of California, Irvine. Clinical details, demographic data, and functional data including timed get up (TGU), manual muscle testing, hand grip, pinch dynamometry, as well as IBM functional rating scale (IBMFRS), modified Rankin score, forced vital capacity (FVC), and modified ocular bulbar facial respiratory scale (mOBFRS) were collected on all patients. Descriptive statistics and Pearson's r correlation were performed to analyze the data. Age of the patient did not correlate with any of the outcome measures. Greater severity of IBMFRS scores correlated with longer disease duration as well as greater severity for FVC, strength outcomes, TGU, modified Rankin, and mOBFRS. Additionally, TGU strongly correlated with muscle strength measurements, modified Rankin, and mOBFRS. mOBFRS moderately correlated with IBMFRS, muscle strength, FVC, TGU and modified Rankin score. We demonstrate moderate to strong correlations among the disease severity outcome measures in this study.

A cross-sectional analysis of clinical evaluation in 35 individuals with mutations of the valosin-containing protein gene.

Inclusion body myopathy (IBM) associated with Paget disease of the bone and frontotemporal dementia or IBMPFD is an autosomal dominant degenerative disorder caused by mutations in the valosin-containing protein (VCP) gene. We aim to establish a detailed clinical phenotype of VCP disease amongst 35 (28 affected individuals, 7 presymptomatic gene carriers) individuals versus 14 unaffected first-degree relatives in 14 families to establish useful biomarkers for IBMPFD and identify the most meaningful tests for monitoring disease progression in future clinical trials. Comprehensive studies included the Inclusion Body Myositis Functional Rating Scale (IBMFRS) and fatigue severity scale questionairres, strength measurements using the Manual Muscle Test with Medical Research Council (MRC) scales, hand-held dynamometry using the microFET and Biodex dynamometers, 6 minute walk test (6MWT), and pulmonary function studies. Strong correlation was observed between the IBMFRS and measurements of muscle strength with dynamometry and the other functional tests, indicating that it may be utilized in long-term follow-up assessments due to its relative simplicity. This cross-section study represents the most comprehensive evaluation of individuals with VCP disease to date and provides a useful guide for evaluating and possible monitoring of muscle weakness and pulmonary function progression in this unique cohort of individuals.