PMID: 2495906May 1, 1989Paper

Comparison of responses to methacholine and cold air in patients suspected of having asthma

Chest
R B FilukN R Anthonisen

Abstract

In 140 adult patients with FEV1 greater than or equal to 60 percent predicted referred because of suspected asthma, we compared responses to methacholine and isocapnic cold-air hyperventilation. Most challenges were accomplished on the same day, cold air always being done first. The cold-air test employed a single episode of hyperventilation (target, 30 times the FEV1), and subsequent FEV1 changes were noted, a decrease of 10 percent being defined as a positive test result. For methacholine, subjects inhaled aerosols of increasing concentrations and the dose associated with a 20 percent decline in FEV1 (PC20) was noted; positive tests were defined as a 20 percent decrease at concentrations less than or equal to 8 mg/ml. Of the 140 patients, 65 had negative results on both challenges. Twelve patients had positive results on cold-air testing but negative responses to methacholine, and 17 had the opposite result. Among patients with positive results to either test, there was a significant correlation (p less than 0.001) between change in FEV1 with cold air and log PC20, but there was considerable scatter, the results of one test accounting for 25 percent of the variability in the other. Some scatter may have been related to the me...Continue Reading

References

Dec 1, 1987·The American Review of Respiratory Disease·P TessierJ L Malo
Aug 20, 1987·The New England Journal of Medicine·E R McFadden
Sep 1, 1982·Thorax·N M WilsonM Silverman
Aug 1, 1983·The Journal of Allergy and Clinical Immunology·J W WeissR H Ingram
Nov 1, 1981·The Journal of Allergy and Clinical Immunology·F E HargreaveJ Dolovich

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Citations

Aug 4, 2009·Journal of Veterinary Internal Medicine·R D Nolen-WalstonA M Hoffman
Dec 31, 1997·American Journal of Respiratory and Critical Care Medicine·E LombardiF D Martinez
Mar 14, 2012·The Journal of Allergy and Clinical Immunology·Robert S TepperAlkis Togias
Jul 17, 2012·The Journal of Asthma : Official Journal of the Association for the Care of Asthma·Aaron B HolleyStuart Roop
Oct 24, 1997·Respiratory Medicine·H O KoskelaH O Tukiainen
Sep 24, 2005·Pediatric Allergy and Immunology : Official Publication of the European Society of Pediatric Allergy and Immunology·Hosne Ara FerdousiSten Dreborg

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