RESUMO
Abstract Background: Most international studies on epidemiology of transient loss of consciousness (TLC) were performed many years ago. There are no data about the lifetime prevalence of TLC in Russia. Objective: To identify the lifetime prevalence and presumed mechanisms of TLC in an urban Russian population. Methods: 1796 individuals (540 males [30.1%] and 1256 females [69.9%]) aged 20 to 69 years (mean age 45.8 ± 11.9 years) were randomly selected and interviewed within the framework of multicentre randomised observational trial. Results: The overall prevalence of TLC in the studied population was 23.3% (418/1796), with the highest proportion (28%) seen in 40-49 year age group. TLC was significantly more common in women than in men (27.5% vs 13.5%). The mean age of patients at the time of the first event was 16 (11; 23) years, with 333 (85%) individuals experiencing the first episode of TLC under 30 years. The average time after the first episode of TLC was 27 (12; 47) years. The following mechanisms of TLC were determined using the questionnaire: neurally-mediated syncope (56.5%), arrhythmogenic onset of syncope (6.0%), nonsyncopal origin of TLC (1.4%), single episode during lifetime (2.1%). Reasons for TLC remained unidentified in 34% cases. 27 persons (6.5%) reported a family history of sudden death, mainly patients with presumably arrhythmogenic origin (24%). Conclusion: Our findings suggest that the overall prevalence of TLC in individuals aged 20-69 years is high. The most common cause of TLC is neurally-mediated syncope. These data about the epidemiology can help to develop cost-effective management approaches to TLC.
Resumo Fundamento: A maioria dos estudos internacionais sobre epidemiologia da perda de consciência temporária (PCT) foi realizada há muitos anos. Não há dados sobre sua prevalência ao longo da vida na Rússia. Objetivo: Identificar a prevalência ao longo da vida e os supostos mecanismos da PCT em uma população russa urbana. Métodos: 1.796 indivíduos (540 homens 30,1% e 1.256 mulheres 69,9%) com idade entre 20 e 69 anos (idade média, 45,8 ± 11,9 anos) foram selecionados aleatoriamente e entrevistados no contexto de um estudo multicêntrico randomizado observacional. Resultados: A prevalência global de PCT na população estudada foi 23,3% (418/1.796), sendo a mais alta proporção (28%) observada na faixa etária de 40-49 anos. PCT foi significativamente mais comum nas mulheres (27,5% vs 13,5%). A idade média dos pacientes por ocasião do primeiro evento foi 16 (11; 23) anos, com 333 (85%) indivíduos experienciando o primeiro episódio de PCT antes dos 30 anos. O tempo médio após o primeiro episódio de PCT foi 27 (12; 47) anos. Os seguintes mecanismos de PCT foram determinados usando-se um questionário: síncope neuromediada (56,5%), síncope de origem arritmogênica (6,0%), PCT de origem não sincopal (1,4%), episódio único durante a vida (2,1%). A causa de PCT não foi identificada em 34% dos casos, sendo que 27 pacientes (6,5%) relataram história familiar de morte súbita, principalmente aqueles com PCT de suposta origem arritmogênica (24%). Conclusão: Nossos achados sugerem uma alta prevalência global de PCT em indivíduos com idade entre 20 e 69 anos. A causa mais comum de PCT é a síncope neuromediada. Esse dado sobre a epidemiologia pode contribuir para o desenvolvimento de abordagem custo-efetiva para PCT.
Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Inconsciência/etiologia , Inconsciência/epidemiologia , Doenças Cardiovasculares/complicações , Arritmias Cardíacas/complicações , População Urbana , Doenças Cardiovasculares/genética , Prevalência , Inquéritos e Questionários , Federação Russa/epidemiologia , Distribuição por Sexo , Distribuição por Idade , Síncope Vasovagal/diagnóstico , Predisposição Genética para Doença , Morte Súbita/etiologiaRESUMO
BACKGROUND: Most international studies on epidemiology of transient loss of consciousness (TLC) were performed many years ago. There are no data about the lifetime prevalence of TLC in Russia. OBJECTIVE: To identify the lifetime prevalence and presumed mechanisms of TLC in an urban Russian population. METHODS: 1796 individuals (540 males [30.1%] and 1256 females [69.9%]) aged 20 to 69 years (mean age 45.8 ± 11.9 years) were randomly selected and interviewed within the framework of multicentre randomised observational trial. RESULTS: The overall prevalence of TLC in the studied population was 23.3% (418/1796), with the highest proportion (28%) seen in 40-49 year age group. TLC was significantly more common in women than in men (27.5% vs 13.5%). The mean age of patients at the time of the first event was 16 (11; 23) years, with 333 (85%) individuals experiencing the first episode of TLC under 30 years. The average time after the first episode of TLC was 27 (12; 47) years. The following mechanisms of TLC were determined using the questionnaire: neurally-mediated syncope (56.5%), arrhythmogenic onset of syncope (6.0%), nonsyncopal origin of TLC (1.4%), single episode during lifetime (2.1%). Reasons for TLC remained unidentified in 34% cases. 27 persons (6.5%) reported a family history of sudden death, mainly patients with presumably arrhythmogenic origin (24%). CONCLUSION: Our findings suggest that the overall prevalence of TLC in individuals aged 20-69 years is high. The most common cause of TLC is neurally-mediated syncope. These data about the epidemiology can help to develop cost-effective management approaches to TLC.