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Ethnopharmacological Relevance: Muscular dystrophies are a rare, severe, and genetically inherited group of disorders characterized by progressive loss of muscle fibers, leading to muscle weakness. The current treatment plan for muscular dystrophies includes the use of steroids to slow muscle deterioration by dampening the inflammatory response., Aim of the Study: Chinese herbal medicine (CHM) has been offered as an adjunctive therapy in Taiwan's medical healthcare plan, making it possible to track CHM usage in patients with muscular dystrophic disease. Therefore, we explored the long-term effects of CHM use on the overall mortality of patients with muscular dystrophies., Materials and Methods: A total of 581 patients with muscular dystrophies were identified from the database of Registry for Catastrophic Illness Patients in Taiwan. Among them, 80 and 201 patients were CHM users and non-CHM users, respectively. Student's t-test, chi-squared test, Cox proportional hazard model, and Kaplan-Meier curve (log-rank test) were used for evaluation. Association rules and network analyses were performed to explore the combination of CHMs used in muscular dystrophies., Results: Compared to non-CHM users, there were more female patients, more comorbidities, including chronic pulmonary disease and peptic ulcer disease in the CHM user group. Patients with prednisolone usage exhibited a lower risk of overall mortality than those who did not, after adjusting for age, sex, use of CHM, and comorbidities. CHM users showed a lower risk of overall mortality after adjusting for age, sex, prednisolone use, and comorbidities. The cumulative incidence of the overall survival was significantly higher in CHM users. Association rule and network analysis showed that one main CHM cluster was commonly used to treat patients with muscular dystrophies in Taiwan. The cluster includes Yin-Qiao-San, Ban-Xia-Bai-Zhu-Tian-Ma-Tang, Zhi-Ke (Citrus aurantium L.), Yu-Xing-Cao (Houttuynia cordata Thunb.), Che-Qian-Zi (Plantago asiatica L.), and Da-Huang (Rheum palmatum L.)., Conclusions: Our data suggest that adjunctive therapy with CHM may help to reduce the overall mortality among patients with muscular dystrophies. The identification of the CHM cluster allows us to narrow down the key active compounds and may enable future therapeutic developments and clinical trial designs to improve overall survival in these patients., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Background: Cardiomyopathy is a common complication among muscular dystrophy (MD) patients and often results in advanced heart failure and premature death. In spite of this, there is hesitancy to consider heart transplantation (HTx). This study describes the HTx outcomes in patients with MD in the United States., Methods and Results: All HTx in the United Network for Organ Sharing database from October 1, 1987, to March 31, 2016, were identified. Two patient groups were created: MD cohort (n=81), and a cohort of all other cardiomyopathies, called cardiomyopathy-unmatched (n=41 317). Propensity score matching (ratio 1:2) was performed on transplant age, gender transplant year, renal function, and inotropic support at transplant to form a cardiomyopathy-matched cohort (n=162). Patient characteristics and posttransplant outcomes were compared. In the 81 patients with MD, Becker was the most common type (42%-52%). All the analyzed preoperative characteristics did not statistically differ between the MD and cardiomyopathy-matched cohorts except ventricular assist device use (16% versus 30%; P =0.017), ventilator support (0% versus 6%; P =0.031), and donor race mismatch (30% versus 55%; P <0.001). Median time on waitlist was not statistically different between the 2 groups (52 versus 59 days; P =0.12). Posttransplant survival of MD cohort was not statistically different compared with cardiomyopathy-matched cohort ( P =0.18; hazard ratio [95% CI], 0.71 [0.42-1.18]) and was better than the cardiomyopathy-unmatched cohort ( P =0.004; hazard ratio [95% CI], 0.53 [0.34-0.82]). Among the types of MD, no statistical difference was observed in posttransplant survival of Becker MD versus non-Becker MD ( P =0.12; hazard ratio [95% CI], 2.17 [0.79-6.01])., Conclusions: Patients with MD undergoing HTx had similar long-term posttransplant survival compared with matched cardiomyopathy-related HTx recipients. HTx appears to be an effective treatment for a select group of muscular dystrophy patients with end-stage heart failure.

Background/aims: Duchenne Muscular Dystrophy (DMD) has childhood onset, primarily affects males, and is usually fatal before the age of 40 years. Previous studies have indicated that this X-linked condition is more prevalent in whites than in blacks, but those were based on active surveillance, and limited to smaller populations and younger ages., Methods: US death data were used to calculate mortality rates by race and ethnicity, with MD as either the underlying or multiple cause of death (MCD). Poisson approximation was used for confidence intervals; chi-square was used to compare rates., Results: From 2006 to 2015, there were 3,256 deaths in males <40 years with MD as MCD, and 71% of these were aged 15-29 years. For whites, the average annual death rate was 0.43/100,000, which was significantly higher (p < 0.0001) that that of blacks (0.28), American Indian/Alaska Natives (0.20), and Asian/Pacific Islanders (0.21). The rate for non-Hispanic whites (0.46) was significantly higher (p < 0.0001) than the rates for Hispanic whites (0.31), Hispanic blacks (0.07), and non-Hispanic blacks (0.29)., Conclusion: Since DMD is the primary cause of deaths in young males with MD, mortality rates are a reasonable proxy for the relative difference in racial prevalence. It appears that DMD is significantly more common in white males than in males of other races., (© 2018 S. Karger AG, Basel.)

Long-term non-invasive ventilation (NIV) was introduced in the 1980s, initially mainly for patients with poliomyelitis, muscular dystrophy (MD) or scoliosis. The obesity-hypoventilation syndrome has since become the commonest reason for referral to most centres providing home-NIV. Patients with MD are numerically a much smaller part of the workload, but as their disease progresses the need for ventilatory support changes and they require regular comprehensive assessment of their condition. We have examined the trend in MD use of home-NIV in our unit over the last 25 years. The number of new referrals appears to be stabilizing at around 20-25 over a 5-year period, equivalent to approximately 0.5 per 100,000 of population per year. The mean age at commencement of home-NIV is now 37.5 years, with 5-year survival rates of 70-75%. Ten-year survival rates are just over 40%. The distance of usual place of residence from our unit is fairly stable, currently at a mean of 27 km. Excellent survival rates mean that patients with MD, while numerically small, are likely to remain an important part of the workload of centres providing home-NIV. Our data should prove useful in the planning of future services for this group of patients.

Background: In France, referral centres in teaching hospitals were created 10 years ago to provide MD patients with treatments and follow-up designed to prevent complications and improve outcomes. Respiratory failure is a major cause of death among subjects with MD, and its prevention and treatment can serve as a touchstone for assessing the effectiveness of MD care pathways., Objective: We report data from a preliminary study of admissions of MD patients in France and of factors associated with mortality, with special emphasis on respiratory failure [RF]., Methods: Retrospective analysis of the data from the French nationwide hospital database [Programme de M é dicalisation des syst é mes d'information, PMSI] for 2009 and 2010., Results: 7187 admissions of patients with MD were included in the study. Most admissions were to teaching hospitals [5913/7187, 82.3%]. 302 [4.2%] patients were admitted for RF requiring invasive ventilation, 924 [12.9%] for RF requiring only NIV or high-flow oxygen therapy, and 5961 [82.9%] required no respiratory assistance. 494 [6.9%] admissions occurred on an emergency basis. 77/7187 [1.1%] patients died while hospitalised. Teaching-hospital admission was associated with lower frequencies of emergency admission [3.08% vs. 24.5%, p < 0.01] and in-hospital death [0.71% vs. 2.75%, p < 0.01]., Conclusions: Our data suggest that there is room for improvement in care pathways for MD patients requiring admission. Admission to referral centres may provide the best outcomes.Further studies are needed to assess associations between healthcare pathways and outcomes of MD subjects.

Phosphorodiamidate morpholino oligomer (PMO)-mediated exon skipping is among the more promising approaches to the treatment of several neuromuscular disorders including Duchenne muscular dystrophy. The main weakness of this approach arises from the low efficiency and sporadic nature of the delivery of charge-neutral PMO into muscle fibers, the mechanism of which is unknown. In this study, to test our hypothesis that muscle fibers take up PMO more efficiently during myotube formation, we induced synchronous muscle regeneration by injection of cardiotoxin into the tibialis anterior muscle of Dmd exon 52-deficient mdx52 and wild-type mice. Interestingly, by in situ hybridization, we detected PMO mainly in embryonic myosin heavy chain-positive regenerating fibers. In addition, we showed that PMO or 2'-O-methyl phosphorothioate is taken up efficiently into C2C12 myotubes when transfected 24-72 h after the induction of differentiation but is poorly taken up into undifferentiated C2C12 myoblasts suggesting efficient uptake of PMO in the early stages of C2C12 myotube formation. Next, we tested the therapeutic potential of PMO for laminin-α2 chain-null dy(3K)/dy(3K) mice: a model of merosin-deficient congenital muscular dystrophy (MDC1A) with active muscle regeneration. We confirmed the recovery of laminin-α2 chain and slightly prolonged life span following skipping of the mutated exon 4 in dy(3K)/dy(3K) mice. These findings support the idea that PMO entry into fibers is dependent on a developmental stage in myogenesis rather than on dystrophinless muscle membranes and provide a platform for developing PMO-mediated therapies for a variety of muscular disorders, such as MDC1A, that involve active muscle regeneration.

Background: Muscular dystrophies (MDs), characterized by progressive muscle wasting, are associated with 1 in 2,500 deaths in the United States. Although treatments slow the progression, these disorders lead to early death, usually due to cardiac or respiratory failure., Methods: We analyzed death record data from 18,315 MD-associated deaths that occurred in the United States in 1986 through 2005 to assess trends in the age at death of people with MDs., Results: From 1986 through 2005, the MD-associated mortality rate did not change among blacks, whites, males, or females. The median age at death among white females with MDs was 12 years higher than among black females. The frequency of reported cardiomyopathy increased among white but not black male decedents with MDs, although cardiomyopathy remained more commonly reported among black males. Among white males, the median age at death increased by 0.2 annually for those with and 1.3 for those without indications of cardiomyopathy. Among black males, the median age at death increased 0.3 years annually among those without reported cardiomyopathy. Among white males, the frequencies of pulmonary failure and pulmonary infection decreased significantly over time., Conclusions: Changes in age at death and reported clinical comorbidities reflect improvements in the treatment of MDs. White males with MDs have shown a greater increase in age at death over time than black males. Contributing factors to this difference might include differences in types of MDs, rates of genetic and environmental modifiers, natural history, socioeconomic factors, and access to and use of treatment options.

Major advances in the fields of medical science and physiology, molecular genetics, biomedical engineering, and computer science have provided individuals with muscular dystrophy (MD) with more functional equipment, allowing better strategies for improvement of quality of life. These advances have also allowed a significant number of these patients to live much longer. As progress continues to change management, it also changes patients' expectations. A comprehensive medical and rehabilitative approach to management of aging MD patients can often fulfill expectations and help them enjoy an enhanced quality of life.

This article deals with the neurological basis of brainstem-related symptoms in disabled children. Synaptic interactions of respiratory and swallowing centers, which are briefly reviewed in this study, highlight the significance of the nucleus of solitary tract (NTS) in the stereotyped motor events. Coordination mechanisms between these two central pattern generators are also studied with a focus on the inhibitory action of decrementing expiratory neurons that terminate the inspiratory activity and become activated during swallowing. Dorsal brainstem lesions in hypoxic-ischemic encephalopathy (HIE) affect the area including NTS, and result in symptoms of apneusis, facial nerve paresis, dysphagia, gastroesophageal reflux, and laryngeal stridor. Leigh syndrome patients with similar distributions of medullary lesions show increased sighs, post-sigh apnea, hiccups, and vomiting in addition to the symptoms of HIE, suggesting pathologically augmented vagal reflex pathways. The present article also discusses the pathophysiology of laryngeal dystonia in xeroderma pigmentosum group A, self-mutilation in Lesch-Nyhan syndrome, and sudden unexpected death in Fukuyama congenital muscular dystrophy. Close observation and logical assessment of brainstem dysfunction symptoms should be encouraged in order to achieve better understanding and management of these symptoms in disabled children.

Objective: To describe the course, complications, and prognosis of Ullrich congenital muscular dystrophy (UCMD), with special reference to life-changing events, including loss of ambulation, respiratory insufficiency, and death., Methods: Review of the case notes of 13 patients with UCMD, aged 15 years or older at last visit, followed up at a tertiary neuromuscular centre, London, UK, from 1977 to 2007. Data collected were age at onset of symptoms, presenting symptoms, mobility, contractures, scoliosis, skin abnormalities, respiratory function, and feeding difficulties., Results: The mean age at onset of symptoms was 12 months (SD 14 months). Eight patients (61.5%) acquired independent ambulation at a mean age of 1.7 years (SD 0.8 years). Nine patients (69.2%) became constant wheelchair users at a mean age of 11.1 years (SD 4.8 years). Three patients continued to ambulate indoors with assistance. Forced vital capacity (FVC) values were abnormal in all patients from age 6 years. The mean FVC (% predicted) declined at a mean rate of 2.6% (SD 4.1%) yearly. Nine patients (69.2%) started noninvasive ventilation at a mean age of 14.3 years (SD 5.0 years). Two patients died of respiratory insufficiency., Conclusion: In Ullrich congenital muscular dystrophy (UCMD), the decline in motor and respiratory functions is more rapid in the first decade of life. The deterioration is invariable, but not always correlated with age or severity at presentation. This information should be of help to better anticipate the difficulties encountered by patients with UCMD and in planning future therapeutic trials in this condition.

To identify trends and patterns associated with muscular dystrophy (MD)-associated deaths, we analyzed population-based data from death certificates in the Multiple Cause Mortality Files compiled by the National Center for Health Statistics. From 1983 to 1998, 14,499 deaths in the United States were associated with ICD-9 codes for MD. The mortality rate for MD in the general U.S. population over this time period was 0.365 per 100,000 persons per year. Stratification by age at death revealed a trimodal distribution with peaks at 0, 17, and 62 years. The male-to-female ratio varied with age at death, a pattern consistent with a mixture of autosomal and X-linked MDs with different prognoses. Deaths related to MD appeared to be equally divided between presumed autosomal and X-linked MDs. The mortality rate was higher in Whites than in Blacks, for both autosomal and X-linked MDs. The median age at death was lower in Blacks than Whites for both males and females. Cardiac complications were more commonly noted among MD-associated deaths in Blacks (38.9%) than Whites (28.6%). Respiratory infections were noted in about 20% of MD-associated deaths and were more common in winter than summer months. Potential reasons for the racial differences include differences in prevalence rates, rates of diagnosis, and reporting on death certificates. Additional studies are needed to resolve these issues. Challenges in the interpretation of these data include the lack of ICD-9 codes specific for individual MDs and potential recording biases in underlying cause of death and contributing factors. We also present a method for estimating autosomal and X-linked contributions to the overall mortality rate of a genetically heterogeneous condition such as MD.

Respiratory failure is an important terminal event in muscular dystrophy, but increasingly is effectively treated by non-invasive ventilation. This study was designed to assess mortality statistics in this patient group in order to get an indication of future demand. Mortality data for all deaths from muscular dystrophy registered by death certification in England and Wales between 1993 and 1999 were analysed. In total, 817 deaths from muscular dystrophy were registered between 1993 and 1999. Annual number of deaths was unchanged over this period. Median age at death (interquartile range) for all cause muscular dystrophy increased from 20 (17-42.5) years in 1993, to 26 (17.5-63) years in 1999. Respiratory failure was the primary or contributory cause of death in 82% of cases. Two thirds of these deaths were during acute infection. We can expect 100 patients with muscular dystrophy to develop respiratory failure in England and Wales each year, so non-invasive ventilation services probably need to be able to provide for 0.2 new patients per 100,000 population annually. Respiratory services also need to provide adequate monitoring and early treatment of infection in these patients.

Muscular dystrophies (MD) are a clinically and genetically heterogeneous disease group. In the last few years, remarkable progress has been made in understanding the close und various relations between skeletal muscle disease and heart muscle disease. Cardiac involvement has been documented in a number of primary MDs and is even the dominant feature in some of them. The myocardium can be affected in the form of a dilated cardiomyopathy while the conduction system can be affected resulting in arrhythmias and conduction defects. Many patients with MD die because of cardiac complications like sudden cardiac death or congestive heart failure. Detailed clinical data about cardiac involvement are available for Duchenne/Becker MD, Emery-Dreifuss MD, myotonic dystrophy, and the different limb girdle MDs. Cardiac manifestations were also found in congenital MD, central core disease, proximal myotonic myopathy, and nemaline myopathy. No data about cardiac abnormalities are available in oculopharyngeal MD and rippling muscle disease. The heart of patients with primary MD should be carefully investigated because of the life-threatening events caused by cardiac complications. There is a strong need for a close collaboration between neurologists and cardiologists in order to provide optimal disease management for the affected patients.

Myostatin is a TGF-beta family member and a negative regulator of skeletal muscle growth. It has been proposed that reduction or elimination of myostatin could be a treatment for degenerative muscle diseases such as muscular dystrophy. Laminin-deficient congenital muscular dystrophy is one of the most severe forms of muscular dystrophy. To test the possibility of ameliorating the dystrophic phenotype in laminin deficiency by eliminating myostatin, we crossed dy(W) laminin alpha2-deficient and myostatin null mice. The resulting double-deficient dy(W)/dy(W);Mstn(-/-) mice had a severe clinical phenotype similar to that of dy(W)/dy(W) mice, even though muscle regeneration was increased. Degeneration and inflammation of muscle were not alleviated. The pre-weaning mortality of dy(W)/dy(W);Mstn(-/-) mice was increased compared to dy(W)/dy(W), most likely due to significantly less brown and white fat in the absence of myostatin, and postweaning mortality was not significantly improved. These results show that eliminating myostatin in laminin-deficiency promotes muscle formation, but at the expense of fat formation, and does not reduce muscle pathology. Any future therapy based on myostatin may have undesirable side effects.

Objective: To quantitate prolongation of survival for patients with Duchenne muscular dystrophy with the use of noninvasive intermittent positive-pressure ventilation (IPPV) with and without access to a protocol involving mechanically assisted coughing., Design: In this retrospective review of all patients with Duchenne muscular dystrophy visiting a neuromuscular disease clinic, patients were trained to use mouth piece and nasal IPPV and mechanically assisted coughing to maintain oxyhemoglobin saturation >94% (protocol). Survival was considered prolonged when noninvasive IPPV was required full time., Results: Ninety-one of 125 patients used noninvasive IPPV part time for 1.9 +/- 1.3 yr, and 51 went on to require it full time for 6.3 +/- 4.6 yr. Of the 31 noninvasive IPPV users who died without access to the protocol, 20 died from respiratory causes and seven died from cardiac causes. None of the 34 full-time noninvasive IPPV users with access to the protocol underwent tracheotomy or died from respiratory complications during a period of 5.4 +/- 4.0 yr, whereas three died from heart failure. Five patients with no breathing tolerance were extubated or decannulated to continuous noninvasive IPPV., Conclusions: Noninvasive respiratory aids can prolong survival and permit extubation or decannulation of patients with Duchenne muscular dystrophy with no breathing tolerance.

REM-related oxygen desaturation occurs in advanced Duchenne muscular dystrophy (DMD) and might be an independent predictor of disease progression. We have followed 18 patients for 10 yr after an initial respiratory sleep study or until death or onset of nasal ventilation. We measured baseline spirometry, blood gas tensions, maximal respiratory pressures, and body mass index. In 11 cases, VC was recorded serially. Median survival was 50 (range, 13 to 89) mo from initial study and unrelated to age at time of study, BMI, or mouth pressures but correlated with PaCO2 (r = -0.72, p < 0.005, n = 17), minimal nocturnal SaO2 (r = 0.62, p < 0.007, n = 18) and VC (r = 0. 65, p < 0.005, n = 17). Cox regression analysis showed a VC of less than 1 L at the time of study to be the best single predictor of subsequent survival. The only measure associated with age of death was the age at which the VC fell below 1 L (r = 0.79, p < 0.004). These data suggest measurement of PaCO2 or serial assessment of VC should be studied further as valid methods of assessing prognosis in DMD.

Purpose: To explore the use of neuroendocrine monitoring for more timely diagnosis of dilated cardiomyopathy (DCM) in Duchenne's muscular dystrophy (DMD) and to determine the effects of angiotensin-converting enzyme inhibitors (ACEI) and beta-blockers on neuroendocrine levels, left ventricular diastolic diameter (LVDd), ejection fraction, and mortality rate on DMD., Methods: Eighty-five patients with DMD underwent yearly cardiac monitoring including neuroendocrine screening. Eleven patients had symptoms of DCM develop once plasma neuroendocrine levels increased. At this point the patients received ACEI for 9 to 62 months (35.8 +/- 18.4 months) and beta-blockers for 7 to 60 months (31.6 +/- 20.1 months)., Results: The combination of ACEI and beta-blockers relieved symptoms and signs of heart failure in all 11 patients and significantly reduced atrial natriuretic protein (ANP) levels from 197.5 +/- 152.1 pg/mL to 25.5 +/- 16.2 pg/mL ( P <.002) at 15.5 +/- 8.2 months, brain natriuretic protein from 523.8 +/- 434.8 pg/mL to 59.3 +/- 24. 2 pg/mL ( P <.05) at 12.2 +/- 3.1 months (data complete for 5 patients), norepinephrine levels from 1114 +/- 689 pg/mL to 360 +/- 257 pg/mL at 20.5 +/- 9.6 months for 11 patients (P =.001), and LVDd from 65.9 +/- 9.2 mm to 63.3 +/- 6.3 mm (P =.15) at 15.0 +/- 7.4 months for 10 patients, including 3 for whom the LVDd increased by 2 to 6 mm. The combination increased left ventricular ejection fraction (LVEF) from 25.1% +/- 9.2% to 36.5% +/- 5.8% (P <.001) at 17.1 +/- 11.0 months for 10 patients. For 9 of the patients ANP levels remained lower throughout the 36.8 +/- 20.1 month course of the follow-up. Two patients had sudden severe re-elevations of ANP levels just before death from congestive heart failure after 44 and 23 months of therapy, respectively., Conclusion: Neuroendocrine level monitoring can assist in the diagnosis of DCM in patients with DMD. Combination therapy with ACEI and beta-blockers can significantly decrease neuroendocrine activation and LVDd and reverse symptoms and signs of congestive heart failure for patients with DMD.

Twenty-two patients (mean age = 67.9 years) with oculopharyngeal muscular dystrophy (OPMD) were referred for dysphagia from 1987 to January 1995. Six patients had suffered aspiration pneumonia, and three had significantly lost weight, while 19 complained of discomfort during swallowing but without weight loss. Swallowing was assessed by fiberscopy during swallowing (last eight patients), videofluoroscopy (12 cases) and manometry (19 cases). Twelve patients underwent a cricopharyngeal (CP) myotomy: 10 showed improvement, one had a partial improvement, and the procedure failed in one (mean follow-up = 29.6 months). In the other cases, CP myotomy was postponed, refused or contraindicated. Of the 22 patients, three died from OPMD consequences. Factors associated with favorable outcome were adequate residual pharyngeal propulsion and no weight loss. In a majority of cases, CP myotomy constitutes an effective treatment of dysphagia with adequate residual propulsion but does not modify the final prognosis and is contraindicated in cases with pharyngeal aperistalsis.

Within the last 30 years, sixty-five patients exhibiting the clinical symptoms of oculopharyngeal muscular dystrophy (OPMD) were studied at the Neuromuscular Diseases Unit of the Neurological Institute of Montevideo. They are members of five unrelated families which came from the Canary Islands to Uruguay between 1850 and 1900. In the three families examined, the typical inclusions characteristic of OPMD were found in the nuclei of muscle fibers. Treatment for ptosis and dysphagia was discussed. The particular migratory pattern of this group of patients could be of considerable interest in the study of molecular genetics.

A subset of patients with congenital muscular dystrophy (CMD) are deficient for the extracellular matrix protein, merosin. Although the aetiology of merosin-positive CMD is as yet unknown, abnormalities of other structural muscle-specific proteins are likely to be involved. The alpha-actinins are actin-binding proteins related to dystrophin. We studied expression of the skeletal muscle isoforms of alpha-actinin (alpha-actinin-2 and alpha-actinin-3) in muscle biopsies from 12 patients with pure CMD (including one with a merosin abnormality), two with unclassified CMD and central nervous system (CNS) involvement, and three with other neuromuscular disorders. Four specimens exhibited deficient alpha-actinin-3 staining by immunofluorescence and/or Western blot analysis. In one, this pattern may be a secondary consequence of marked type 1 fibre predominance, but the other three biopsies contained abundant type 2 fibres where alpha-actinin-3 is normally expressed. Three alpha-actinin-3-deficient patients had pure CMD and presented in the newborn period with muscle weakness, hypotonia and arthrogryposis. The fourth had a dystrophic muscle biopsy and CNS involvement. These results suggest that deficiency of alpha-actinin-3 may be a marker for a subset of patients with CMD. It remains to be determined whether the deficiency of alpha-actinin-3 reflects ACTN3 gene mutations or is a secondary phenomenon.

We studied 23 DMD and eight BMD patients using cardiac echo, 24 h ECG and positron emission tomography (PET) with the radiotracers N-13 ammonia and F-18 fluorine deoxyglucose. The ECG was abnormal in 23 cases with alterations in the PR and/or QT intervals, abnormal Q waves in the lateral leads and ST segment depression. Twenty-four hour ECG showed that patients were more likely to produce premature ventricular ectopic beats with advancing age and 17 patients had paroxysmal ST segment depression. LV function was normal or mildly reduced in 24 cardiac echoes. PET studies were visibly abnormal in 15 patients. Regional perfusion defects involving the apex, lateral or anterior left ventricular walls were present, nine cases demonstrated a corresponding increase in glucose metabolism. Three out of 15 demonstrated matched perfusion/metabolism defects. One BMD had severe LV dilation with globally poor perfusion and metabolism. The abnormalities seen with PET were confirmed with both quantitative and semi-quantitative analysis of radioactive counts. Similar results were obtained for both DMD and BMD, where both groups demonstrated significant regional perfusion/metabolism mismatches. We have shown a reduced uptake of N-13 ammonia which is indicative of a reduction in myocardial perfusion. The use of N-13 ammonia to measure perfusion has been validated in animal studies. PET with either N-13 ammonia- or oxygen labelled water can be used to measure myocardial perfusion. We chose N-13 ammonia as this was most readily available to us.

Sixty-five members of three families with limb girdle muscular dystrophy (LGMD) underwent neurological, cardiological, and ancillary investigations. Thirty-five individuals were diagnosed as having slowly progressive autosomal dominant LGMD. Symmetrical weakness started in the proximal lower limb muscles, and gradually upper limb muscles also became affected. Early contractures of the spine were absent. Contractures of elbows and Achilles tendons were either minimal or late. Serum creatine kinase activity was normal to moderately elevated. Electromyogram and muscle biopsy were consistent with a mild muscular dystrophy. Cardiological abnormalities, found in more than one-half the patients, included dysrhythmias and atrioventricular (AV) conduction disturbances presenting as bradycardia, syncopal attacks necessitating pacemaker implantation, and sudden cardiac death. There was a significant relation between the severity of AV conduction disturbances and age. In nearly all patients, neuromuscular symptomatology preceded cardiological involvement. The early recognition of this previously not described, autosomal dominant LGMD with life-threatening cardiac involvement offers an opportunity for therapeutic intervention.

The goals of this study were to describe the clinical course of skeletal, cardiac, and gastrointestinal muscle manifestations and trends in age at diagnosis and survival of Duchenne muscular dystrophy (DMD) patients. A retrospective cohort of 33 male patients with DMD, born between 1953 and 1983 and followed at the Mayo Clinic during their second decade of life, was studied. The mean age at DMD diagnosis was 4.6 years. Skeletal muscle weakness present in all patients at diagnosis progressed to wheelchair dependency in 32 patients (97%) by the age of 13 years (median age 10 years). Cardiac muscle failure developed in 5 patients (15%) (median age 21.5 years). Smooth muscle manifestations related to the digestive and urinary tracts occurred in 7 (21%) and 2 (6%) patients (median age 15 years), respectively. The gastrointestinal dilatations were primary in 2 patients or secondary to surgery or acute respiratory illness in 5 patients. By the end of the study period, 17 deaths had occurred (median age 17 years). Over time, there was a decrease in the time to DMD diagnosis (P = .05) but no significant change in survival (P = .44). Cardiac and smooth muscle manifestations occur late in the course of DMD. Clinical gastrointestinal symptoms related to smooth muscle function most often were secondary to surgery or a respiratory illness. In recent years, the diagnosis of DMD has been made at a younger age, but survival has not changed.

Background: The effect on subsequent respiratory function of spinal stabilisation for scoliosis in Duchenne muscular dystrophy is unclear. In order to clarify this clinical problem, changes in the forced vital capacity of a group of children with Duchenne muscular dystrophy who had undergone spinal surgery were measured and compared with a group of children with Duchenne muscular dystrophy who had not had surgery., Methods: In this retrospective study 17 boys with Duchenne muscular dystrophy who underwent spinal stabilisation at a mean age of 14.9 years (surgical group) were compared with 21 boys with Duchenne muscular dystrophy who had not had surgery (non-surgical group). The mean (SD) Cobb angle of the surgical group at 14.9 years was 57 (16.4) degrees, and of the non-surgical group at 15 years was 45 (29.9) degrees. Forced vital capacity expressed as percentage predicted (% FVC) was measured in total over a seven year period in the surgical group and over 6.5 years in the non-surgical group, and regression equations were calculated. Survival curves for both groups were also constructed., Results: No difference was found between spinal stabilisation (surgical group) and the non-surgical group in the rate of deterioration of % FVC which was 3-5% per year. There was no difference in survival in either group., Conclusions: Spinal stabilisation in Duchenne muscular dystrophy does not alter the decline in pulmonary function, nor does it improve survival.

The Becker's Muscular Dystrophy (BMD) is a disease with similar aspect and distribution to the Duchenne Muscular Dystrophy (DMD), although it is usually less severe. The main purpose of this investigation was to outline the most important clinical characteristics that can help in the differential diagnosis between these two diseases. Thirty eight patients were studied; 16 with BMD and 22 with DMD. Clinically both are very similar, and the best criteria for the differentiation of this two diseases is the inability to walk. The age of symptomatology onset was 10.5 +/- 7.2 years in BMD and 2.3 +/- 13 years in DMD showing an overlapping of 18.42% of DMD and DMB at the age of 4, this overlapping difficult the precise diagnosis between both diseases. The creatine kinase (CK) study was not relevant.

Although developmental disabilities are among the major chronic health problems affecting children in the United States, the contribution of developmental disabilities to childhood mortality is unknown. To investigate the magnitude of this contribution, multiple cause-of-death data were examined for US children, aged 1-19 years, for 1980 and 1983-1989. The following conditions were included as developmental disabilities: autism, attention deficit disorder, learning disorders, mental retardation, cerebral palsy, epilepsy, muscular dystrophy, blindness and deafness. Based on underlying cause only, it was found that developmental disabilities were the fifth leading cause of nontraumatic death for children between 1 and 14 years of age and the third leading cause of non-traumatic death for children between 15 and 19 years. When a multiple cause approach was used to define developmental disability-related deaths (i.e. when contributing as well as underlying cause was considered), the number of such deaths nearly doubled. On the basis of both underlying- and multiple-cause analyses, cerebral palsy was the developmental disability most frequently cited as a cause of death. Mental retardation ranked second according to the multiple-cause approach but only fourth according to the underlying-cause approach. The least frequent causes of death (autism, attention deficit disorder, learning disorders, blindness, and deafness) were the ones most likely to be coded as contributing rather than underlying causes. Developmental disability-related mortality rates were highest among children aged 1-4 and 15-19 years, highest among blacks and lowest among racial groups other than blacks and whites, and higher among males than females. Although results of multiple-cause-of-death analyses more accurately reflect the proportion of deaths related to developmental disabilities, even this approach may underestimate the degree to which mortality is associated with a developmental disability.

We describe eleven mid-western Canadian aboriginal infants with a unique, progressive muscle disorder. All except one had muscle biopsy and/or autopsy. The infants were normal newborns who rapidly developed rigidity of all skeletal muscles, with early, respiratory insufficiency. Death occurred before 18 months of age. Electromyography showed increased insertion activity and profuse fibrillation potentials; motor unit potentials and interference pattern are normal until late in the course. Pathologic features include progressive, granular to powdery Z-band transformation, myofibrillar loss, and muscle regeneration. SDS-gel electrophoresis of one muscle sample revealed increased 54kDa and reduced 80kDa protein fractions. This disease differs from other conditions with Z-band alterations because of continuous muscle activity and relentless clinical progression. The clinical features, elevated serum creatine kinase, electromyographic and muscle biopsy findings suggest a dystrophic process. The recognition of this condition as an autosomal recessive disorder allows appropriate genetic counselling.

Congenital muscular dystrophy (CMD) comprises a heterogeneous group of muscle disorders. We report on two stillborn sibs with early lethal CMD and a prematurely born boy who died within minutes after birth. The pregnancies were complicated by polyhydramnios. All presented with arthrogryposis multiplex congenita, severe muscle wasting, lung hypoplasia, and hydrops. The muscle biopsies showed fibrosis, variation in fiber size, and extensive fat replacement compatible with muscular dystrophy. Fatal CMD seems to be distinct from CMD with survival after birth and is probably autosomal recessively inherited.

The case cards for autopsied patients with Fukuyama type congenital muscular dystrophy (FCMD) which included clinical data and pathological findings were filled in 10 national hospitals and 2 other institutes in Japan. The cards of 24 patients who died between 1978 and 1991 were collected and analysed for this study. The ages at death ranged from 2 to 27 years with a mean of 14.29 +/- 6.18 years and represented a nearly unimodal distribution. The age at death in the 12 patients who died before 1983 ranged from 2 to 21 years and averaged 11.58 +/- 5.11 years, whereas the 12 patients who died after 1984 ranged from 3 to 27 years of age and averaged 17.00 +/- 6.44 years. The latter group lived significantly longer than the former (p < 0.05). Pulmonary infection was a more frequent cause of demise in the group of patients who died before 1983 than in those who died after 1984 (83.3% vs 25.0%). On the other hand, cardiac failure was a more common cause of death in the latter group (8.3% vs 50.0%). These data on the life spans and cause of death of FCMD were similar to those studied of Duchenne muscular dystrophy by Mukoyama et al (1984, 1986, 1987).(ABSTRACT TRUNCATED AT 250 WORDS)

Eighteen boys with Duchenne muscular dystrophy (DMD) were assessed for their ability to perform tasks involving wrist and hand function. Each subject was assessed using the Jebsen Test of Hand Function, range of motion measurements, and muscle strength tests. Writing and simulated page turning were performed successfully by boys in all age groups. Boys over age 15 had difficulty completing simulated feeding and picking up large and small objects. The muscle strength of the wrist extensors and the radial deviation range of motion at the wrist were found to be strongly correlated with six of the seven tasks assessed. These two clinical assessments appear to be good indicators of overall wrist and hand function. Life expectancy with DMD is increasing with advances in respiratory care making preservation of wrist and hand function, the major activity remaining with advanced disease, increasingly important.

End of life care for patients with Duchenne muscular dystrophy (DMD) has become increasingly complex because of new technologies, changes in medical personnel over periods of time, emergence of home health care systems, and increasing patient and family autonomy in decision-making. In this review, we discuss the medical problems, particularly respiratory and cardiac failure, faced by DMD patients. Current concepts concerning the evaluation and options for treatment of these problems are presented as well as the ethical issues involved in the care of the DMD patient. These issues include the medical indications for treatment, patient preferences, quality-of-life issues, and contextual features related to legal, institutional, religious, geographic, cultural, social, and financial factors. We also present our experience at Loma Linda University Medical Center over the past 10 years in the development of a home mechanical ventilation program for DMD patients and an algorithm for the evaluation of these patients. Many patients with DMD do well on long-term ventilation, but some find that their quality of life is less than desirable and choose to discontinue this method of life-prolongation. Many of these new options are very expensive, making the decision to use them a difficult one. Ultimately, these are societal issues that require clear reflection on matters of resource allocation that should be performed by health care professionals, citizens, and health planners.

We studied 27 Duchenne muscular dystrophy patients having spinal fusion for scoliosis. One patient died intraoperatively of cardiac arrest; all others have done well with no instances of malignant hyperthermia, postoperative ventilatory system dependence, pneumothorax, persisting infection, neurologic damage, nonunion, or pain. The anesthetic management included primarily intravenous general anesthetics with minimal myocardial depressant effects, avoiding succinylcholine and inhalation agents. Preoperative cardiac studies aided anesthetic management intra-operatively. There was an almost universal sinus tachycardia. Holter monitoring defined 4 of 16 with ventricular premature beats, 4 of 16 with atrial premature beats, and no ventricular tachycardia or atrial flutter or fibrillation. Echocardiogram demonstrated mitral prolapse in 2 of 22, frequent abnormal systolic performance with abnormal shortening fraction less than 28% in 7 of 16, and reduced rate-corrected velocity of fiber shortening in 9 of 15. Afterload was elevated in 7 of 15. The mean forced vital capacity (FVC) preoperatively was 45.3 +/- 15.9% with continuing diminution to 28.7 +/- 14.9% at 3.3 +/- 2.2 years after surgery. The main benefit of surgical stabilization is the relative ease and comfort of wheelchair seating compared with those nonoperated patients who develop progressive deformity. We have not seen lasting improvement or stabilization in FVC following surgery as decreasing function is related primarily to muscle weakness.

Of 55 patients with Duchenne muscular dystrophy offered surgical stabilisation of the spine, 32 accepted and 23 refused. We compared both groups pre-operatively and at six-month intervals in respect of survival, forced vital capacity, peak expiratory flow rate and severity of scoliosis. In the nonoperated patients, the forced vital capacity deteriorated by a mean of 8% per annum; in the operated group it remained static for 36 months and diminished slightly thereafter. Spinal stabilisation resulted in an improvement in the peak expiratory flow rate which was maintained for up to five years. In the nonoperated patients the scoliosis progressed from a mean of 37 degrees to a mean of 89 degrees at five years; in the stabilised spines it was improved from a mean of 47 degrees to a mean 34 degrees at five years. There was significantly improved survival in the patients who had undergone spinal stabilisation.

Mutations causing Duchenne muscular dystrophy (DMD) have a short survival. Therefore, birth and population prevalence are maintained by new mutations. The present inventory was made to estimate the birth and population prevalence rates of DMD in the Netherlands. Seven methods of case identification were used. Data on 496 definite, probable or possible DMD patients born since 1961, or alive on January 1, 1983, were obtained. Several methods gave an estimated ascertainment of more than 95%. The prevalence rate at birth of DMD was estimated at 23.7 x 10(-5) (1:4215) male live births (MLB) yearly. The prevalence rate in the male population on January 1, 1983 was 5.4 x 10(-5) (1:18496). About 1% of the males in this study may have autosomal recessive Duchenne-like muscular dystrophy. Until now there has been no convincing evidence for geographic differences in DMD prevalence at birth. A list of frequency studies of Duchenne muscular dystrophy is included. The DMD mutation rate calculated by the indirect method is 7.9 x 10(-5) genes per generation. However, this may well be an over-estimate, as this method does not account for germline mosaicism. Using a modified sex ratio method the proportion of sporadic DMD among all cases was estimated to be 0.106 (range 0-0.332). High frequency of germline mosaicism in DMD is a likely cause for the apparent lack of sporadic cases as found in previous studies, if mutation rates in male and female gametes are equal. Therefore, methods for estimating the proportion of new mutants in DMD should take germline mosaicism into account. The modified sex ratio method allows incorporation of data on germline mosaicism if available.

Cardiac involvement is common in patients with Duchenne type muscular dystrophy (DMD). However, published reports of long-term follow-up studies in the same patients are very rare. The purpose of this study was to clarify the natural course of cardiac dysfunction in DMD, and to analyze the relationship between the deterioration of cardiac function and skeletal muscular function. The cardiac function was serially evaluated for 2-12 years in 34 patients with DMD. The systolic time intervals and echocardiography were used for evaluating the cardiac function. The PEP/ET (pre-ejection period/ejection time) of systolic time intervals significantly deteriorated in 9-12 years (p less than 0.001). The maximal systolic and diastolic endocardial velocity (MSEV and MDEV) and the D/S ratio of echocardiography significantly deteriorated in 5 years (p less than 0.001). The D/S ratio is the ratio of the mean systolic velocity and the mean diastolic velocity of the left ventricular posterior wall. In almost half the patients, the deterioration of these parameters was correlated with that of Swinyard's stage. The Swinyard's functional ability stage demonstrates the grade of the skeletal muscular dysfunction. However, there was no correlation between the deterioration of cardiac function and Swinyard's stage in the other half of the patients. Correlation coefficient in the whole group was 0.32 (p = n.s.) between the PEP/ET and Swinyard's stage, and was -0.15 (p = n.s.) between the D/S ratio and Swinyard's stage. Although the mean left ventricular ejection fraction calculated using echocardiography was slightly decreased for 5 years, no significant change was detected in the whole group. One patient had progressive deterioration of left ventricular function despite mild skeletal muscular dysfunction, and died from congestive heart failure. The cardiac dysfunction was predominant. We named it 'cardiac type' DMD. Since deterioration of cardiac function was not always correlated with deterioration of skeletal muscular function (Swinyard's stage), cardiac function must be carefully monitored in patients with DMD.

Skeletal muscle maturation is impaired in children with congenital myotonic dystrophy. This immaturity is characterized at the light microscopy level by an abnormal presence of myotubes, small fascicles of muscle fibers, thin myofibers, and delayed muscle fiber type differentiation with a peripheral halo lacking mitochondrial oxidative enzyme activity. At an ultrastructural level, the characteristics are a paucity of myofibrils with a peripheral rim devoid of mitochondria and myofibrils in the fibers. In time the muscle is able to gain a certain degree of maturity as shown in one of our cases who had two successive muscle biopsies. The muscle, however, never becomes normal but retains discrepancies in fiber size and fiber type distribution and shows some fiber necrosis. Maturation of the motoneurons is normal, which may explain necrosis of immature muscle fibers. In an experimental study carried out to look for evidence of a circulatory factor in mothers of children with congenital myotonic dystrophy, it was found that sera from these mothers administered intra-peritoneally to newborn rats does in fact impair muscle maturation, whereas rats injected similarly with sera from control women showed normal muscle maturation.

Death in the late stage of Duchenne muscular dystrophy is most frequently a consequence of respiratory failure. Since muscles of ventilation become weakened the bellows mechanism fails insidiously. Patients exhibit symptoms of ventilatory insufficiency, the first to be noticed are those associated with CO2 retention: dyspnea, nightmares, increased heart rate, and increased blood pressure. Ten patients with late stage Duchenne muscular dystrophy have been supplied with mechanical aid for ventilatory assistance. The age of onset of respiratory distress needing mechanical assistance varied from 10 to 20 years. Meaningful survival after allegedly reaching the end stage has been from 2 to 7.5 years with an average of 3.4 years. With a caring family, these patients can have a meaningful life, even though they require continuous mechanical ventilatory aid.

Rate of advance of disability and age at death were studied in patients with Duchenne muscular dystrophy (DMD). A comparison was made between DMD patients under care in their own homes and those hospitalized in National Suzuka Hospital. In 45 patients with home care, rate of advance of disability was considerably high in their age of 6 to 12 years, the average being 0.83 stage per year after the N.Y. University-Ueda's rating stage of disability. In the age of 12 to 17 years, however, the disease progression was much slower, the average being 0.14 stage per year. Beyond 18 years old, the average stage of disability was constantly 7.7, meaning almost bedridden stage. On the contrary, in 56 patients with institutionalized care, the average rate of advance was lower, being 0.5 stage per year in the age of 7 to 15 years and 0.13 stage per year from 15 to 23 years of age. The result of statistical analysis indicated that the stage of disability was significantly higher in the patients under the home care than those with institutionalized care at the age of 12-16, 18 and 19 years. The age when the patients became unable to walk was 9.7 +/- 1.8 years (mean +/- SD) in those with home care and 10.9 +/- 2.3 years in those with institutionalized care. The difference was statistically significant (p less than 0.01). The age at death was 18.3 +/- 3.8 years in 19 DMD patients with home care and 20.4 +/- 3.6 years in 33 patients with institutionalized care. The difference was also statistically significant (p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Duchenne muscular dystrophy (DMD) is one of the most serious neuromuscular afflictions in childhood. The present analysis describes clinical, genetic and epidemiological features in a total of 675 DMD cases, 666 males and 9 females, reported from 20 national hospitals for muscle diseases in Japan. The results are as follows: 1) Average ages of milestones of progression were: onset at 3.6 +/- 1.7, Gower's sign 5.2 +/- 2.3, inability to walk 9.8 +/- 2.1, death 19.5 +/- 3.6 years old, respectively. The patients died 10.9 +/- 3.3 years after the age of inability to walk. 2) Proportion of selected abnormalities (knee contracture, ankle contracture, kyphoscoliosis) and abnormal findings in electrocardiograms increased with age, whereas pseudohypertrophy of the calves, abnormal findings of electromyograms, and mental retardation remained constant. 83-95% of patients were unable to turn the body in bed over 20 years old. 3) Survival rates at 20 and 27 years old were 63%, and 35%, respectively. The 50% survival rate was observed in 22-23 years of age. 4) The proportion of the sporadic cases was compatible with 1/3, as expected for on X-linked lethal trait assuming complete penetrance. 5) The incidence rate and prevalence rate among males were estimated to be 29.2 x 10(-5) and 6. 7 x 10(-5), respectively. The estimated mutation rates in egg and sperm were 9.2 x -5 and 10.9 x 10(-5)/gamete/generation, respectively.

The authors report a case of antenatal diagnosis which is original in that a maternal illness was discovered that had not been thought of until then. Steinert's myotonic dystrophy can show up in two types after birth, a congenital type and a lethal type. The antenatal diagnosis at present consists in a combination of hydramnios and lack of fetal movements on ultrasound. The obstetrical complications are the threat of premature labour and, often, breech presentation. The method of delivery will depend on how severely the fetus is affected; which is worked out by looking for features of poor prognosis. In the future it will be possible to make an antenatal diagnosis by villus biopsy with the discovery of the responsible gene.