The objective of the study was to assess differences among LGMD subtypes and determine differences and associations in quality of life (QOL) measures and clinical endpoints. Assessments included muscle strength, motor function, cardiac and respiratory assessments as well as QOL questionnaires which included the Individualized Neuromuscular Quality of Life Questionnaire (INQoL) and ACTIVLIM. 

Limb-girdle muscular dystrophy (LGMD) describes a heterogeneous group of muscle disorders characterized by a predominantly proximal distribution of limb–girdle weakness.  

A cross sectional multi-site pilot study conducted by the Cooperative International Neuromuscular Research Group (CINRG) to evaluate patients with LGMD2I, 2A, 2B, Becker Muscular Dystrophy and unaffected age matched controls to assess clinical phenotype and quality of life and serum biomarkers. 

 A total of 52 patients with a mean age of 37.5 +12.8 including 29 males and 23 females. LGMD/BMD subgroups totaled 41 patients with 11 controls. Of those with LGMD/BMD, 25 were ambulatory and 16 were non-ambulatory. In LGMD cases, a significant correlation was observed between the INQoL subcategory of ability to perform activities of daily living (ADL) and the 6 minute walk test (6MWT) distance (r=-0.68; p=0.001).  INQoL total scores also showed significant correlations with ankle dorsiflexors (r=-0.55; p=0.002) and total manual muscle testing (MMT) scores (r=-0.50; p=0.005). The ACTIVLIM showed a significant association between the 6MWT and the ability to walk outdoors (p<0.001) as well as the ability to get out of a car (p=0.03). ACTIVLIM questions of washing (p=0.03) and wiping (p=0.003) oneself showed a significant association with the Brooke scale.  Other analyses of cardiac and respiratory function and the ability to perform ADLs did not show significant relationships.  

There has not been confirmation of clinical endpoints that correlate to patient reported outcomes in LGMD. This study shows initial evidence that the INQoL and ACTIVLIM may be useful measures for future clinical trials.