title: Prevalence and progression of mitochondrial diseases: a study of 50 patients.
abstract: We report 50 patients with various clinical phenotypes of mitochondrial disease studied over the past 10 years in a large urban area (Madrid Health Area 5). The clinical phenotypes showed a large variety of abnormalities in molecular biology and biochemistry. The prevalence of mitochondrial diseases was found to be 5.7 per 100,000 in the population over 14 years of age. Clinical and electrophysiological assessment reveal signs of neuropathy in 10 patients. Electromyographic findings consistent with myopathy were obtained in 37 cases. Six patients died of medical complications. Disease phenotype influenced survival to some degree (P < 0.01). Age of onset and gender were not associated with differences in survival. Mitochondrial disease is thus far more common than expected and a common cause of chronic morbidity.
authors.affiliation: Department of Neurology, La Paz Hospital, Paseo de la Castellana 261, 28046 Madrid, Spain. jarpag@ctv.es
authors.forename: Javier
authors.initials: J
authors.lastname: Arpa
authors.forename: Antonio
authors.initials: A
authors.lastname: Cruz-Martínez
authors.forename: Yolanda
authors.initials: Y
authors.lastname: Campos
authors.forename: Manuel
authors.initials: M
authors.lastname: Gutiérrez-Molina
authors.forename: Francisco
authors.initials: F
authors.lastname: García-Rio
authors.forename: Concepción
authors.initials: C
authors.lastname: Pérez-Conde
authors.forename: Miguel A
authors.initials: MA
authors.lastname: Martín
authors.forename: Juan C
authors.initials: JC
authors.lastname: Rubio
authors.forename: Pilar
authors.initials: P
authors.lastname: Del Hoyo
authors.forename: Ana
authors.initials: A
authors.lastname: Arpa-Fernández
authors.forename: Joaquín
authors.initials: J
authors.lastname: Arenas
mesh_terms: D000293:Adolescent; D000328:Adult; D017668:Age of Onset; D000368:Aged; D004272:DNA, Mitochondrial / Q000235:genetics; D018450:Disease Progression; D004576:Electromyography; D004831:Epilepsies, Myoclonic / Q000453:epidemiology / Q000235:genetics / Q000473:pathology; D005260:Female; D006801:Humans; D019344:Lactic Acid / Q000097:blood; D017241:MELAS Syndrome / Q000453:epidemiology / Q000235:genetics / Q000473:pathology; D008297:Male; D008875:Middle Aged; D028361:Mitochondrial Diseases / Q000453:epidemiology* / Q000235:genetics / Q000473:pathology*; D018482:Muscle, Skeletal / Q000473:pathology; D009431:Neural Conduction / Q000502:physiology; D017246:Ophthalmoplegia, Chronic Progressive External / Q000453:epidemiology / Q000235:genetics / Q000473:pathology; D010641:Phenotype; D013030:Spain / Q000453:epidemiology; D016019:Survival Analysis
chemical_list: D004272:DNA, Mitochondrial; D019344:Lactic Acid