Occupational Asthma Reference

Troyanov S, Ghezzo H, Cartier A, Malo JL, Comparison of circadian variations using FEV1 and peak expiratory flow rates among normal and asthmatic subjects, Thorax, 1994;49:775-780,

Keywords: FEV1, peak flow, cosinor

Known Authors

André Cartier, Hôpital de Sacré Coeur, Montreal, Quebec, Canada André Cartier

Jean-Luc Malo, Hôpital de Sacré Coeur, Montreal, Quebec, Canada Jean-Luc Malo

If you would like to become a known author and have your picture displayed along with your papers then please get in touch from the contact page. Known authors can choose to receive emails when their papers receive comments.

Abstract

BACKGROUND--Most studies that describe circadian variations in asthma have used maximum rate of peak expiratory flow (PEF) rather than forced expiratory volume in one second (FEV1) to assess airway calibre. This study was designed to assess circadian variations in PEF and FEV1 measured simultaneously and to compare variations in these measurements in normal and asthmatic subjects in a stable clinical state.

METHODS--Twenty nine subjects (nine asthmatic subjects on bronchodilators, 10 on inhaled steroids, and 10 normal controls) were asked to record their PEF and FEV1 with a new portable instrument every two hours during the day and once on waking at night for two weeks. Circadian variations were examined in different ways using arithmetical indices and cosinor analysis.

RESULTS--78% of PEF values and 75% of FEV1 values were considered to be reproducible and were included in the analysis. Variations obtained using PEF did not differ from those obtained using FEV1. Significant cosinor variations were found in at least 50% of recording days for most of the subjects and showed the same features as for arithmetical indices. Daily variations in PEF and FEV1 were significantly correlated with airway calibre and PC20 methacholine (r approximately 0.5 to approximately 0.6).

CONCLUSIONS--PEF is as satisfactory as FEV1 for describing circadian variations among normal subjects and stable asthmatic subjects

Full Text

Full text of this reference not available

Please Log In or Register to add the full text to this reference

Associated Questions

There are no associations for this paper.

Please Log In or Register to put forward this reference as evidence to a question.

Comments

Please sign in or register to add your thoughts.


Oasys and occupational asthma smoke logo