Efficacy and Tolerability of Ivabradine for Cardiomyopathy in Patients with Duchenne Muscular Dystrophy.

Duchenne muscular dystrophy (DMD) is an intractable X-linked myopathy caused by dystrophin gene mutations. Patients with DMD suffer from progressive muscle weakness, inevitable cardiomyopathy, increased heart rate (HR), and decreased blood pressure (BP). The aim of this study was to clarify the efficacy and tolerability of ivabradine treatment for DMD cardiomyopathy.A retrospective analysis was performed in 11 patients with DMD, who received ivabradine treatment for more than 1 year. Clinical results were analyzed before (baseline), 6 months after, and 12 months after the ivabradine administration.The initial ivabradine dose was 2.0 ± 1.2 mg/day and the final dose was 5.6 ± 4.0 mg/day. The baseline BP was 95/64 mmHg. A non-significant BP decrease to 90/57 mmHg was observed at 1 month but it recovered to 97/62 mmHg at 12 months after ivabradine administration. The baseline HR was 93 ± 6 bpm and it decreased to 74 ± 12 bpm at 6 months (P = 0.011), and to 77 ± 10 bpm at 12 months (P = 0.008). A linear correlation (y = 2.2x + 5.1) was also observed between the ivabradine dose (x mg/day) and HR decrease (y bpm). The baseline LVEF was 38 ± 12% and it significantly increased to 42 ± 9% at 6 months (P = 0.011) and to 41 ± 11% at 12 months (P = 0.038). Only 1 patient with the lowest BMI of 11.0 kg/m2 and BP of 79/58 mmHg discontinued ivabradine treatment at 6 months, while 1-year administration was well-tolerated in the other 10 patients.Ivabradine decreased HR and increased LVEF without lowering BP, suggesting it can be a treatment option for DMD cardiomyopathy.

Natural history of Becker muscular dystrophy: a multicenter study of 225 patients.

OBJECTIVE: Becker muscular dystrophy (BMD) is a milder variant of Duchenne muscular dystrophy (DMD), a lethal X-linked muscular disorder. Here, we aim to investigat the clinical involvement of skeletal, respiratory, cardiac, and central nervous systems in patients with BMD, as well as genotype-phenotype relationships. METHODS: This nationwide cohort study investigated the clinical manifestations and genotype-phenotype relationships in 225 patients with BMD having in-frame deletion from 22 medical centers. The primary outcome was to elucidate the association of genotype with skeletal muscle, respiratory, cardiac, and central nervous system disorders. Descriptive statistics were used to analyze the data. RESULTS: The average age of the subjects was 31.5 (range, 1-81) years. Initial symptoms of BMD were muscular (60%), followed by asymptomatic hypercreatine kinasemia (32.4%) and central nervous system disorders (5.3%). Gait disturbance was observed in 53.8% of patients and the average age at wheelchair introduction was 36.5 years. The ventilator introduction rate was 6.7% at an average age of 36.6 years. More than 30% of patients had an abnormal electrocardiogram and approximately 15% had heart failure symptoms. Cardiac function on echocardiography varied significantly among the patients. The frequencies of seizures and intellectual/developmental disability were 8.0% and 16.9%, respectively. Exon 45-47deletion (del) was the most common (22.6%), followed by exon 45-48del (13.1%). Patients with exon 45-49del patients demonstrated severe skeletal muscle damage. Patients with exon 45-47del and exon 45-55del patients did not require ventilator use. INTERPRETATION: The study provides important prognostic information for patients and clinicians to establish therapy plans and to implement preventative medicine.

Deep Vein Thrombosis in Severe Motor and Intellectual Disabilities Patients and Its Treatment by Anticoagulants of Warfarin Versus Edoxaban.

Objective: Patients with severe motor and intellectual disabilities (SMID) often develop complications, including paralysis of the extremities due to abnormal muscular tonicity. Furthermore, the incidence of sudden death, which may be caused by pulmonary thromboembolism (PTE), is approximately 4.2%. Deep vein thrombosis (DVT) is attracting attention as an embolic source. In this study, DVT was confirmed in SMID patients by lower extremity venous ultrasound. The oral anticoagulant, warfarin, and novel oral anticoagulant, edoxaban tosilate hydrate, were administered, and their efficacies and safeties were evaluated. Materials and Methods: DVT patients were randomly allocated to warfarin and edoxaban groups. The frequency of hemorrhagic events and incidence of adverse events were investigated to evaluate efficacy and safety. Results: DVT was detected in 14 (8.4%) out of 167 patients. Four (0.067/person-month) hemorrhagic events occurred in the warfarin group from subcutaneous hemorrhage due to bruises caused by postural changes. Three (0.042/person-month) events occurred in the edoxaban group due to nasal hemorrhage caused by tracheal aspiration. There was no significant difference (p=0.5383) between groups. Conclusion: No significant differences were observed in hemorrhagic events between SMID patients with DVT treated with warfarin and edoxaban.

Multicenter, Open-Label, Randomized Controlled Trial of Warfarin and Edoxaban Tosilate Hydrate for the Treatment of Deep Vein Thrombosis in Persons with Severe Motor Intellectual Disabilities.

Sudden death in patients with severe motor and intellectual disabilities (SMID) is sometimes caused in part by pulmonary thromboembolism (PTE), and deep venous thrombosis (DVT) has drawn attention as a possible embolic source. Warfarin, which is a conventional therapeutic agent, is not easy to control appropriately, and daily management can be especially difficult in SMID patients. On the other hand, edoxaban tosilate hydrate, which has been newly approved for insurance coverage for the treatment of DVT, is not listed in the Guidelines for the Diagnosis, Treatment and Prevention of Pulmonary Thromboembolism and Deep Vein Thrombosis (DVT-PTE guidelines). The aim of this study is to evaluate the efficacy and safety of anticoagulation therapy (warfarin vs. edoxaban) in DVT treatment in SMID patients by means of an open-label, randomized controlled trial. The primary endpoint is the incidence of hemorrhagic events during 12 months of follow up.

[The association of hypocarnitinemia with enteral diets and antiepileptic drugs in children and adults with severe physical and mental disabilities].

OBJECTIVE: To examine the risk factors of hypocarnitinemia and hypocarnitinemic symptoms in children and adults with severe physical and mental disabilities. METHODS: The status of hypocarnitinemia as well as the related symptoms were assessed in a total of 78 children and adults with severe physical and mental disabilities who were admitted to National Hospital Organization Iou National Hospital. Their enteral diets and the medication of antiepileptic drugs were evaluated. RESULTS: Markedly decreased blood carnitine levels were noted in patients undergoing an enteral diet without carnitine supplementation as well as in those receiving a combination of valproate sodium (VPA) and phenobarbital (PB). These hypocarnitinemic patients tended to have more frequent episodes of hypoglycemia and hyperammonemia. CONCLUSIONS: Supplemental L-carnitine is needed in patients receiving an enteral diet free of carnitine, those with combination therapy of VPA and PB under oral feeding conditions, and those who develop hyperammonemia during VPA therapy. Patients who received a carnitine-supplemented enteral diet maintained their serum carnitine levels with a relatively low supplemental dose of carnitine.

Mutational analysis of TSC1 and TSC2 in Japanese patients with tuberous sclerosis complex revealed higher incidence of TSC1 patients than previously reported.

Tuberous sclerosis complex (TSC) is an autosomal dominant disorder characterized by multiple hamartias and hamartomas involving throughout the body. To date, many TSC1 and TSC2 mutations have been reported all over the world, however, few TSC mutation studies have been performed in the Japanese population, and genetic characteristics of Japanese TSC patients are not yet clear. In this study, we analyzed TSC1 and TSC2 in 57 Japanese patients with TSC (8 familial and 49 sporadic; 46 definite and 11 suspect TSC) and identified 31 mutations including 11 TSC1 mutations (two familial and nine sporadic; all definite TSC) and 20 TSC2 mutations (2 familial and 18 sporadic; 19 definite and 1 suspect TSC). We also reviewed all Japanese TSC mutations previously reported. Our study demonstrates significantly higher incidence (P=0.007) of TSC1 mutations among sporadic TSC patients in the Japanese population compared with US and European studies. No differences emerged in mutation distributions and types in precedent studies, excepting low frequency of the TSC2 nonsense mutation. Comparing clinical manifestations, developmental delay and/or mental retardation were milder in TSC1 patients than TSC2 patients for its frequency (P=0.032) and severity (P=0.015); however, no other symptoms were clearly different.

A case of solitary subependymal giant cell astrocytoma: two somatic hits of TSC2 in the tumor, without evidence of somatic mosaicism.

Subependymal giant cell astrocytoma (SEGA) is a unique brain tumor arising in tuberous sclerosis complex (TSC), an autosomal dominant inherited phacomatosis. There are several case reports of solitary SEGA without any other manifestations of TSC. Usually these cases are thought to be forme fruste of TSC due to somatic mosaicism. However, no previous reports have used molecular methodology to fully investigate mutations in TSC genes or the possibility of somatic mosaicism. Here, we report a 20-year-old woman with a brain tumor. Pathological diagnosis was consistent with SEGA, but comprehensive clinical screening found no other lesions indicative of TSC. Molecular analysis of the tumor revealed loss of heterozygosity and allelic mutation (5228G>A, R1743Q) of TSC2. To detect the small fraction of mosaic mutation in somatic cells, we developed a highly sensitive new method: triple-nested polymerase chain reaction-restriction fragment length polymorphism. The identical TSC2 missense mutation was not detected in any other tissues from the same patient, including peripheral blood, buccal mucosa, urinary sediment, nail, and hair. According to these results, this patient should be considered as having SEGA that developed from two somatic hit mutations in TSC2, rather than being a TSC2 patient with a very small fraction of somatic mosaicism.