Complexity of the Airflow in COPD

Sponsor

Rio de Janeiro State University (Other)

Overall Status

Unknown status

CT.gov ID

NCT01888705

Collaborator

Conselho Nacional de Desenvolvimento Científico e Tecnológico (Other), Rio de Janeiro State Research Supporting Foundation (FAPERJ) (Other)

Enrollment

Location

Duration (Months)

Patients Per Site Per Month

Study Details

Study Description

Brief Summary

Recently, there has been a growing interest in the study of nonlinear dynamics as a methodology for complementary analysis to characterize the respiratory pattern. These methods are well established in studies of heart rate. The analyzes evaluate complex signals, including large-scale fractal correlations and distributions in time series, and can provide relevant clinical information.

Measures such as approximate entropy and sample entropy have shown great potential in the evaluation of the complexity of the respiratory system, providing information relevant to the understanding of physiological and pathophysiological processes. These measures are based on the concept of non-linearity in the presence of a high number of interconnections, resulting in the complex behavior exhibited by physiological systems.

The approximate entropy (ApEn) is related to the amount of clutter, complexity or unpredictability of a data series over time. In a complementary way, the sample entropy (SampEn), is a far more elaborate than the ApEn, to reduce possible biased estimates due to self-similarity.

A study conducted by our group in asthma patients with different levels of bronchial obstruction demonstrated a significant reduction in airflow approximate entropy (ApEnV´) in asthmatic subjects. Investigators believe that in COPD, similar to that which occurs in asthma disorders that are associated with complex changes in the pathophysiology triggering breath control, possibly resulting in changes in air flow (V´).

Considering the development "silent" changes of mechanical ventilation in COPD patients and its clinical relevance, as well as the difficulty of identifying such changes through conventional methods, we observed the need to obtain more detailed information, including the complexity of the system breathing for better understanding of factors that contribute to the illness.

In this context, the objectives of this study were: (1) analyze the influence of airway obstruction in the complexity of the patterns of airflow in patients with COPD, (2) evaluate the diagnostic power of the test in identifying the changes caused by COPD.

Condition or Disease	Intervention/Treatment	Phase
COPD

Study Design

Study Type:

Observational [Patient Registry]

Anticipated Enrollment :

90 participants

Time Perspective:

Cross-Sectional

Official Title:

Complexity of the Airflow at Different Levels of Bronchial Obstruction of COPD.

Study Start Date :

Mar 1, 2010

Anticipated Primary Completion Date :

Jul 1, 2013

Anticipated Study Completion Date :

Dec 1, 2013

Arms and Interventions

Arm	Intervention/Treatment
Control group Group of nonsmokers individuals without respiratory disease.
NE Smokers wiht normal spirometry.
LV Patients with COPD level I, mild.
MOD Patients with COPD level II, moderate.
GV Patients with COPD level III, severe.
MGV Patients with COPD level IV, very severe.

Outcome Measures

Primary Outcome Measures

Respiratory Impedance in Different Phases of the Cycle Ventilation in Patients with Chronic Obstructive Pulmonary Disease [up to 3 years]
The aim of the study was to analyze the changes in the respiratory system impedance (Zrs) in the different phases of the respiratory cycle of patients with Chronic Obstructive Pulmonary Disease (COPD). This research was conducted using a monofrequency version of the forced oscillation technique (mFOT) and consisted of a controlled observational study where 31 individuals were analyzed, 8 controls and 23 individuals with COPD. The patients presented different degrees of airway obstruction.

Eligibility Criteria

Criteria

Ages Eligible for Study:

40 Years to 90 Years

Sexes Eligible for Study:

All

Accepts Healthy Volunteers:

Yes

Inclusion Criteria:

volunteers with COPD for Patients Group;
volunteers without any respiratory disease for the control group.

Exclusion Criteria:

individuals with history of tuberculosis or other lung disease,
heart disease in general and
disability in the exams.

Contacts and Locations

Locations

	Site	City	State	Country	Postal Code
1	Laboratório de Instrumentação Biomédica	Rio de Janeiro		Brazil	21550-013

Sponsors and Collaborators

Rio de Janeiro State University
Conselho Nacional de Desenvolvimento Científico e Tecnológico
Rio de Janeiro State Research Supporting Foundation (FAPERJ)

Investigators

Study Director: Pedro L de Melo, DSc., State University of Rio de Janeiro

Study Documents (Full-Text)

None provided.

More Information

Publications

None provided.

Responsible Party:

Karla Dames, Professor, Rio de Janeiro State University

ClinicalTrials.gov Identifier:

NCT01888705

Other Study ID Numbers:

UERJ-DPOC-01

First Posted:

Jun 28, 2013

Last Update Posted:

Jun 28, 2013

Last Verified:

Jun 1, 2013

Keywords provided by Karla Dames, Professor, Rio de Janeiro State University

Respiratory Mechanics

FOT

Study Results

No Results Posted as of Jun 28, 2013