Neuro-Cardio-Autonomic Modulations in Children with Duchenne Muscular Dystrophy.

BACKGROUND AND OBJECTIVE: Duchenne muscular dystrophy (DMD) is a degenerative X-linked muscle disease. Death frequently results from complications in cardiopulmonary systems. Preclinical/early diagnosis of cardiac autonomic abnormalities may aid initiate cardioprotective therapy and enhance prognosis. METHODS: A cross sectional, prospective study of 38 DMD boys compared with 37 age-matched healthy controls was conducted. Lead II electrocardiography and beat-to-beat blood pressure were recorded to assess heart rate variability (HRV), blood pressure variability (BPV), and baroreceptor sensitivity (BRS) in a standardized environment. Data were analysed and correlated with disease severity and genotype. RESULTS: In the DMD group, the median age at assessment was 8 years [IQR 7-9 years], the median age at disease onset was 3 years [IQR, 2-6 years], and the mean duration of illness was 4 years [IQR, 2.5-5]. DNA sequencing showed deletions in 34/38 (89.5 %) and duplications in 4/38 (10.5%) patients. The median heart rate in DMD children was significantly higher [101.19 (Range, 94.71-108.49)] /min compared to controls [81 (Range, 76.2-92.76)] /min (p < 0.05). All the assessed HRV and BPV parameters were significantly impaired in DMD cases except for the coefficient of variance of systolic blood pressure. Further, BRS parameters were also significantly reduced in DMD, excluding alpha-LF. A positive correlation was found between alpha HF with age at onset and duration of illness. CONCLUSION: This study demonstrates a distinct early impairment of neuro-cardio-autonomic regulation in DMD. Simple yet effective non-invasive techniques such as HRV, BPV, and BRS may help identify cardiac dysfunction in a pre-clinical state, paving the way for early cardio-protective therapies and limiting disease progression in DMD patients.

Mutation pattern in 606 Duchenne muscular dystrophy children with a comparison between familial and non-familial forms: a study in an Indian large single-center cohort.

INTRODUCTION: Duchenne muscular dystrophy (DMD) is induced by a wide spectrum of mutations such as exon deletions, duplications and small mutations in the dystrophin gene. This is the first study on the mutational spectrum in a cohort of DMD children from India, with an emphasis to compare the mutations in familial and sporadic forms. RESULTS: Multiplex ligation-dependent probe amplification (MLPA) and next-generation sequencing (NGS) identified 525 and 70 cases of DMD, respectively, while 11 cases showed absent dystrophin staining with no mutations detected. Families with two or more affected males contributed to 12% of the entire cohort. The mutations comprised of exonic deletions in 492/606 (81.2%), duplications in 33/606 (5.4%) and small mutations (point mutations and INDELs) in 70/606 (11.5%) cases. MLPA identified significantly more larger mutations in sporadic (88.2%) than in familial cases (75.3%). The mutations in NGS were: [nonsense = 40 (57.1%); frameshift = 17 (24.3%); splice variant = 12 (17.1%)]. Nonsense mutations were more common in familial than in sporadic cases: 17.8% vs 10.7%. The familial group reported an earlier onset of disease (2.8 ± 1.7 years) as compared to sporadic cases (3.8 ± 1.6 years). CONCLUSION: MLPA could identify mutations in a high percentage of our DMD children. The preponderance of small mutations was noted to be distinctly higher in the familial group. Intriguingly, the familial form of DMD formed a small percentage of the entire cohort. The reasons could be increasing awareness among parents and physicians with early identification of DMD cases, genetic counseling and prenatal testing.

Autonomic Function in Insular Glioma: An Exploratory Study.

INTRODUCTION: Autonomic nervous system dysfunction is a known entity in strokes involving insula. It causes significant morbidity and mortality. No study to date has demonstrated autonomic nervous system dysfunction in patients with insular glioma. This is an exploratory study to identify the subclinical autonomic dysfunctions in insular glioma. METHODS: A total 50 patients with newly diagnosed insular glioma in the age group of 18-60 years were evaluated with heart rate variability (HRV). All the HRV parameters in patients with insular glioma were compared with normal healthy age- and sex-matched control patients. RESULTS: There was a significant difference (P < 0.05) in most of the HRV parameters between patients and control patients. Patients with left insular glioma showed significantly increased heart rate (P = 0.027), low-frequency normalized units (P = 0.048), and also increased low-frequency/high-frequency ratio (P = 0.015), which indicates sympathetic dominance. Patients with seizures had significantly lower values of total power (P = 0.042). No significant difference was found in terms of the extent and size of the tumor or histopathologic grades of gliomas. CONCLUSIONS: Patients with insular gliomas have significant impairment of autonomic functions, with left insular glioma showing sympathetic dominance. Suppression of autonomic function is greater in those presenting with seizures.