Characterization of individuals with selected muscular dystrophies from the expanded pilot of the Muscular Dystrophy Surveillance, Tracking and Research Network (MD STARnet) in the United States

Abstract

Introduction: Data on muscular dystrophies (MDs), a heterogeneous group of heritable diseases hallmarked by progressive muscle deterioration, are scarce. Objective: We describe cross-sectional sociodemographic and clinical characteristics of individuals with congenital, distal, Emery-Dreifuss, facioscapulohumeral, limb-girdle, myotonic, or oculopharyngeal MD. Methods: The study was conducted in four sites (Arizona, Colorado, Iowa, and 12 western New York counties) as a pilot expansion of the Muscular Dystrophy Surveillance, Tracking and Research Network, funded by the Centers for Disease Control and Prevention. MDs were detected in healthcare facilities and administrative data sources using International Classification of Disease codes. Our sample contains 1,723 individuals with a MD diagnosis and a healthcare encounter between January 1, 2007 and December 31, 2011. Results and Conclusions: Individuals were mostly non-Hispanic and white. Median ages ranged from 9.2 to 66.0 years. Most (98%) had health insurance. The proportion of individuals who were disabled or unable to work increased with age (range: 8.6-46.4%). People with limb-girdle MD aged ≥18 years were more likely to be nonambulatory (range: 24.5-44.7%). The percentages of individuals with documented clinical interventions during the surveillance period were low. The most common cause of death was respiratory causes (46.3-57.1%); an ICD-10 code for MD (G71.1 or G71.0) was reported for nearly one-half. Our findings show wide variability in sociodemographic and clinical characteristics across MDs.

Genetic Patterns of Selected Muscular Dystrophies in the Muscular Dystrophy Surveillance, Tracking, and Research Network

“… 23 A study of EDMD, LGMD, CMD, and DD from the prior MD STAR ne t cycle only detected a skewed male/female ratio in EDMD. 16 Although the available information does not enable us to draw definitive conclusions about the origins of this sex distribution, it is plausible that female individuals affected by these categories of muscular dystrophy were diagnosed at lower rates or sought specialty care less often than affected male individuals during this more recent surveillance period. Milder manifestations in female individuals could account for either explanation.…”

“…Prior geographically defined studies of EDMD, LGMD, CMD, and DD in the United States consist principally of 2 MD STAR net reports that did not include the genetic analysis presented here. 15 , 16 In other countries, epidemiologic studies focusing on LGMD have been published from Austria, 9 Chile, 10 Italy, 11 , 23 the Netherlands, 12 and Spain 13 and CMD from Italy. 14 These and other studies from around the world that covered these diagnoses provide valuable information but had differences in scope from our study because they did not include genetic subtype information, 24 were broad-based general studies of muscle diseases or neuromuscular disorders, 25 - 35 or focused on genetic subsets of one of these muscular dystrophies.…”

“…The Muscular Dystrophy Surveillance, Tracking, and Research Network (MD STAR net ) has reported general sociodemographic and clinical characteristics of individuals with these MDs in specific regions of the United States 15 , 16 ; however, MD STARnet has not previously analyzed detailed patterns of genes and variants associated with the 4 less common MD types. In this report, we characterize such patterns of genetic test results for the 4 MDs under investigation.…”

Characteristics of Clinical Trial Participants with Duchenne Muscular Dystrophy: Data from the Muscular Dystrophy Surveillance, Tracking, and Research Network (MD STARnet)

“…MD STARnet is a population-based public health surveillance program of nine muscular dystrophies, including dystrophinopathies, funded by the Centers for Disease Control and Prevention. Details about MD STARnet were published previously [19][20][21][22][23][24]. For this study, retrospective active surveillance data were collected by six sites: Colorado (CO), Iowa (IA), North Carolina, Piedmont region (NC), South Carolina (SC), Utah (UT), and New York's 21 western counties (wNY).…”

Role of CMR Imaging in Diagnostics and Evaluation of Cardiac Involvement in Muscle Dystrophies

“…As Russo and Nigro [56] mention in their letter to the editors, there is evidence that ventricular events in EDMD can be prevented by proper ICD implantation, and therefore recommend the combined implantation of PM-ICD devices in patients with preserved LVEF. Given the frequent implantation of PM-ICDs [57] and the rarity of the disorder, estimated at 1:100.000, CMR studies are limited to case series [58].…”