Positive Airway Pressure for the Treatment of Asthma
11 de maio de 2017 atualizado por: Robert L. Owens, Brigham and Women's Hospital
Asthma is an extremely common disorder, which is becoming more prevalent.
The purpose of this study is to examine how nocturnal lung volumes contribute to asthma severity, which may explain part of the link between asthma and obesity.
The investigators seek to test the hypothesis that raising lung volumes during the night will improve asthma symptoms.
The investigators work may lead to new targets for therapy.
Visão geral do estudo
Status
Concluído
Condições
Intervenção / Tratamento
Descrição detalhada
Asthma is a chronic respiratory disease characterized by airway inflammation and airway hyperresponsiveness, which causes airflow obstruction. It is extremely prevalent, affecting an estimated 22 million Americans, and costly with loss of productivity and direct healthcare costs in the billions of dollars. The incidence and prevalence of asthma are increasing, both in the US and around the world. This increase comes despite greater understanding of the inflammatory and allergic basis for asthma, and despite better antiinflammatory medications. One explanation for the increasing prevalence of asthma is the concomitant increase in obesity, with the majority of Americans now overweight or obese. Numerous studies have convincingly linked asthma and obesity, and demonstrated increased obstruction with weight gain and decreased obstruction with weight loss. However, the mechanisms that underlie this linkage are not known.
We believe that low lung volumes contribute to the pathogenesis and severity of asthma. End-expiratory lung volume is decreased in obesity, and likely falls further during sleep, particularly in overweight and obese patients. Both upper and lower airway resistance increase with decreasing lung volumes, as airways become smaller. However, prior work has shown that lower airway resistance increases out of proportion to the decrease in lung volume that occurs during sleep in asthma patients. This difference between controls and people with asthma has not been further explored, yet may provide insight into asthma pathogenesis and provide potential targets for therapy.
Therefore, we propose a series of experiments to define the impact of lung volumes during sleep on airway resistance. One of these experiments will be to to test the hypothesis that lung stretch can be used therapeutically by tonically and dynamically increasing lung volumes during sleep using bi-level positive airway pressure. This research can help delineate asthma pathogenesis and may help improve therapeutic options in this exceedingly common disease.
Tipo de estudo
Intervencional
Inscrição (Real)
31
Estágio
- Não aplicável
Contactos e Locais
Esta seção fornece os detalhes de contato para aqueles que conduzem o estudo e informações sobre onde este estudo está sendo realizado.
Locais de estudo
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Massachusetts
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Boston, Massachusetts, Estados Unidos, 02115
- Brigham and Women's Hospital
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Critérios de participação
Os pesquisadores procuram pessoas que se encaixem em uma determinada descrição, chamada de critérios de elegibilidade. Alguns exemplos desses critérios são a condição geral de saúde de uma pessoa ou tratamentos anteriores.
Critérios de elegibilidade
Idades elegíveis para estudo
18 anos a 75 anos (Adulto, Adulto mais velho)
Aceita Voluntários Saudáveis
Não
Gêneros Elegíveis para o Estudo
Tudo
Descrição
Inclusion Criteria:
- mild to moderate asthma, diagnosed by a physician, OR
- mild to moderate asthma and CPAP treated OSA. Must be compliant with CPAP therapy (greater than 4 hours per night, at least 4 nights/week)
Exclusion Criteria:
- lung disease other than asthma or OSA
- medications known to affect respiratory function (apart from asthma and rhinitis therapy)
- abnormal nasal anatomy
- current smokers and ex-smokers (quit within the last 3 months, or >10 pack-years)
- pregnant women - women of child bearing age will undergo a urine pregnancy test before enrollment and during the course of the study, as some of the study procedures cannot be performed during pregnancy and because pregnancy often changes asthma symptoms and severity.
- severe asthma - defined as a recent exacerbation (doctor or ER visit for asthma, or oral steroid use, within the previous 4 weeks) or frequent exacerbations (>4 exacerbations in the last year.
- severe obstructive sleep apnea requiring supplemental oxygen in addition to CPAP therapy.
- the regular use of prescription (e.g. zolpidem) or over-the-counter sleep aids (e.g. Benadryl).
- Central sleep apnea
Plano de estudo
Esta seção fornece detalhes do plano de estudo, incluindo como o estudo é projetado e o que o estudo está medindo.
Como o estudo é projetado?
Detalhes do projeto
- Finalidade Principal: Tratamento
- Alocação: Randomizado
- Modelo Intervencional: Atribuição cruzada
- Mascaramento: Nenhum (rótulo aberto)
Armas e Intervenções
Grupo de Participantes / Braço |
Intervenção / Tratamento |
|---|---|
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Experimental: Usual Care first, then Bilevel PAP
Subjects will begin the study by continuing their usual care for 4 weeks.
They will complete questionnaires and breathing tests at the start and end of this 4 week period.
After a "Washout Period" of an additional 4 weeks of usual care, they will then start Bilevel PAP therapy for 4 weeks.
Just before and after the Bilevel PAP they will complete questionnaires and breathing tests.
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Subjects will use bilevel PAP each night for 4 weeks.
The pressure levels will be adjusted by the investigators to increase lung volumes during the night.
Outros nomes:
Subjects will continue with their usual asthma care.
Investigators will make no changes to their medications or other habits.
Subjects will continue with their usual asthma care in between the Usual Care and Bilevel PAP periods.
Investigators will make no changes to their medications or other habits.
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Experimental: Bilevel PAP first, then Usual Care
Subjects will begin the study by starting on Bilevel PAP for 4 weeks.
Just before and after the Bilevel PAP they will complete questionnaires and breathing tests.
After a 4 week "Washout Period" of usual care, they will start a Usual Care period for 4 weeks.
They will complete questionnaires and breathing tests at the start and end of this 4 week period.
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Subjects will use bilevel PAP each night for 4 weeks.
The pressure levels will be adjusted by the investigators to increase lung volumes during the night.
Outros nomes:
Subjects will continue with their usual asthma care.
Investigators will make no changes to their medications or other habits.
Subjects will continue with their usual asthma care in between the Usual Care and Bilevel PAP periods.
Investigators will make no changes to their medications or other habits.
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O que o estudo está medindo?
Medidas de resultados primários
Medida de resultado |
Descrição da medida |
Prazo |
|---|---|---|
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Asthma Control Test
Prazo: Every 4 weeks during the 12 week study (at the start and end of the Usual Care period, and at the start and end of the Bilevel PAP intervention period)
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Well validated questionnaire of asthma symptoms which includes 5 written questions.
Each question is answered on a scale of 1-5, which are summed to report a range of asthma control from 5 to 25 (higher score indicates better asthma control).
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Every 4 weeks during the 12 week study (at the start and end of the Usual Care period, and at the start and end of the Bilevel PAP intervention period)
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Airway Reactivity as Measured by Methacholine Challenge (PC20)
Prazo: Every 4 weeks during the 12 week study (at the start and end of the usual care period, and at the start and end of the Bilevel PAP intervention period)
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This is a physiological measurement derived from repeated breathing maneuvers which measures airway reactivity.
Subjects are exposed to higher and higher concentrations of an airway irritant (in this case methacholine), and between each dose perform spirometry.
The test is stopped after the forced expiratory volume in 1 second (FEV1) falls 20% below the baseline.
The concentration of methacholine at which this occurs is called the PC20.
Methacholine challenges are routinely used in the diagnosis of asthma, and in many asthma research studies to measure changes in airway reactivity.
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Every 4 weeks during the 12 week study (at the start and end of the usual care period, and at the start and end of the Bilevel PAP intervention period)
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Medidas de resultados secundários
Medida de resultado |
Descrição da medida |
Prazo |
|---|---|---|
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Epworth Sleepiness Scale (ESS)
Prazo: Every 4 weeks during the 12 week study (at the start and end of the usual care period, and at the start and end of the Bilevel PAP intervention period)
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8 item questionnaire to measure daytime sleepiness, with total score reported 0 (less sleepy) to 24 (most sleepy).
Scores greater than or equal to 10 are considered excessive daytime sleepiness.
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Every 4 weeks during the 12 week study (at the start and end of the usual care period, and at the start and end of the Bilevel PAP intervention period)
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Pittsburgh Sleep Quality Index (PSQI)
Prazo: Every 4 weeks during the 12 week study (at the start and end of the usual care period, and at the start and end of the Bilevel PAP intervention period)
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Well validated questionnaire used frequently to measure sleep quality over the prior 1 month.
It consists of 19 individual items that combine to form 7 components summed to create one global score.
The overall score is between 0 (better sleep) and 21 (worse sleep).
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Every 4 weeks during the 12 week study (at the start and end of the usual care period, and at the start and end of the Bilevel PAP intervention period)
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Short Form (SF-36) Health Survey
Prazo: Every 4 weeks during the 12 week study (at the start and end of the usual care period, and at the start and end of the Bilevel PAP intervention period)
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Well validated quality of life questionnaire that measures eight sub-sections, which are summed to yield a score from 0 (maximal disability) to 100 (no disability).
The eight subsections are: vitality, physical functioning, bodily pain, general health perceptions, physical role functioning, emotional role functioning, social role functioning, mental health.
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Every 4 weeks during the 12 week study (at the start and end of the usual care period, and at the start and end of the Bilevel PAP intervention period)
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FEV1 %Predicted
Prazo: Every 4 weeks during the 12 week study (at the start and end of the usual care period, and at the start and end of the Bilevel PAP intervention period)
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Performed as part of spirometry
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Every 4 weeks during the 12 week study (at the start and end of the usual care period, and at the start and end of the Bilevel PAP intervention period)
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Colaboradores e Investigadores
É aqui que você encontrará pessoas e organizações envolvidas com este estudo.
Patrocinador
Colaboradores
Investigadores
- Investigador principal: Robert L Owens, MD, Brigham and Women's Hospital
Datas de registro do estudo
Essas datas acompanham o progresso do registro do estudo e os envios de resumo dos resultados para ClinicalTrials.gov. Os registros do estudo e os resultados relatados são revisados pela National Library of Medicine (NLM) para garantir que atendam aos padrões específicos de controle de qualidade antes de serem publicados no site público.
Datas Principais do Estudo
Início do estudo
1 de julho de 2010
Conclusão Primária (Real)
1 de setembro de 2014
Conclusão do estudo (Real)
1 de dezembro de 2014
Datas de inscrição no estudo
Enviado pela primeira vez
18 de junho de 2010
Enviado pela primeira vez que atendeu aos critérios de CQ
29 de junho de 2010
Primeira postagem (Estimativa)
1 de julho de 2010
Atualizações de registro de estudo
Última Atualização Postada (Real)
17 de maio de 2017
Última atualização enviada que atendeu aos critérios de controle de qualidade
11 de maio de 2017
Última verificação
1 de maio de 2017
Mais Informações
Termos relacionados a este estudo
Termos MeSH relevantes adicionais
- Doenças do Sistema Nervoso
- Doenças Respiratórias
- Doenças do sistema imunológico
- Apnéia
- Distúrbios Respiratórios
- Distúrbios do Sono Intrínsecos
- Dissônias
- Distúrbios do Sono Vigília
- Doenças pulmonares
- Hipersensibilidade, Imediata
- Doenças brônquicas
- Doenças Pulmonares Obstrutivas
- Hipersensibilidade Respiratória
- Hipersensibilidade
- Síndromes da Apneia do Sono
- Asma
Outros números de identificação do estudo
- 2009-P-001733/1
- 1F32HL097578-01 (Concessão/Contrato do NIH dos EUA)
- 5K23HL105542 (Concessão/Contrato do NIH dos EUA)
Essas informações foram obtidas diretamente do site clinicaltrials.gov sem nenhuma alteração. Se você tiver alguma solicitação para alterar, remover ou atualizar os detalhes do seu estudo, entre em contato com register@clinicaltrials.gov. Assim que uma alteração for implementada em clinicaltrials.gov, ela também será atualizada automaticamente em nosso site .