Atopy influences exhaled nitric oxide levels in adult asthmatics.
OBJECTIVE
To examine whether atopy influences exhaled nitric oxide (NO) levels in adults with established asthma.


METHODS
Specialist respiratory unit in a university teaching hospital.


METHODS
Twenty-eight asthmatics (mean FEV(1), 85.7%) receiving short-acting inhaled bronchodilators and a range of inhaled steroids (0 to 4,000 microg/d).


METHODS
Subjects were studied on two occasions, 5 to 7 days apart, between September and March.


RESULTS
On the first day, FEV(1), exhaled NO, and histamine challenge were performed. On the second day, exhaled NO, total IgE, and skin-prick testing to six common allergens were conducted. Exhaled NO was measured with the single exhalation method. We found exhaled NO levels to correlate positively with total IgE (r = 0.43, p = 0.02) and number of positive skin-prick tests (p = 0. 002). By contrast, there was no significant correlation between exhaled NO and FEV(1) or the provocative concentration causing a 20% fall in FEV(1). Subanalyses of steroid-treated and steroid-naive patients in this group revealed the same findings.


CONCLUSIONS
Exhaled NO levels in asthmatics correlate more closely with atopy than with bronchial hyperreactivity and lung function.
Ho
L P
LP
Respiratory Unit, Western General Hospital, Edinburgh, Oxford, United Kingdom.
Wood
F T
FT
Robson
A
A
Innes
J A
JA
Greening
A P
AP
D000280:Administration, Inhalation; D000328:Adult; D000485:Allergens; D000704:Analysis of Variance; D001249:Asthma / Q000188:drug therapy / Q000378:metabolism* / Q000503:physiopathology; D016535:Bronchial Hyperreactivity / Q000503:physiopathology; D001985:Bronchial Provocation Tests; D016085:Bronchoconstrictor Agents; D001993:Bronchodilator Agents / Q000008:administration & dosage / Q000627:therapeutic use; D005260:Female; D005541:Forced Expiratory Volume / Q000187:drug effects / Q000502:physiology; D006632:Histamine; D006801:Humans; D006969:Hypersensitivity, Immediate / Q000378:metabolism*; D007073:Immunoglobulin E / Q000097:blood; D008168:Lung / Q000503:physiopathology; D008297:Male; D009569:Nitric Oxide / Q000378:metabolism*; D012119:Respiration; D012882:Skin Tests; D018709:Statistics, Nonparametric; D013256:Steroids / Q000008:administration & dosage / Q000627:therapeutic use
D000485:Allergens; D016085:Bronchoconstrictor Agents; D001993:Bronchodilator Agents; D013256:Steroids; D009569:Nitric Oxide; D007073:Immunoglobulin E; D006632:Histamine