The importance of serum IgE for level and longitudinal change in airways hyperresponsiveness in COPD.
BACKGROUND
Airways hyperresponsiveness (AHR) is an important feature of patients with chronic obstructive pulmonary disease (COPD). Little is known about factors that modulate AHR in COPD.


OBJECTIVE
To study these factors, we performed a long-term, double-blind, parallel intervention study in 58 male, non-allergic patients with COPD.


METHODS
During a period of 2 years, patients were treated with inhaled budesonide (1600 microg/day), inhaled budesonide (1600 microg/day) plus oral prednisolone (5 mg/day), or placebo. PC20 histamine was measured at 4-monthly intervals. The influence of treatment, smoking, age, level of lung function, initial serum IgE level and peripheral blood eosinophils on level and longitudinal change of PC20 histamine was analysed.


RESULTS
During follow-up, PC20 decreased in our group, and this decrease was not influenced by treatment. PC20 tended to decrease faster in current smokers than in ex-smokers. PC20 was significantly associated with pre-challenge FEV1 at each time point. Level nor decline of PC20 were significantly related to age. A higher initial serum IgE level was independently associated with a lower PC20. Moreover, a higher initial serum IgE level was associated with a slower annual decline of PC20, regardless of treatment, pre-challenge FEV1, and other modulating factors. No significant associations were found between initial blood eosinophils and level or decline of PC20.


CONCLUSIONS
We conclude that AHR increases over time in non-allergic patients with COPD. Treatment with an inhaled corticosteroid alone or in combination with oral prednisolone does not change this increase. Our study suggests an important role for IgE in the course of the disease, since a higher initial serum IgE level predicts a more favourable course with regard to annual decline of PC20 histamine.
Renkema
T E
TE
Department of Pulmonology, University of Groningen, The Netherlands.
Kerstjens
H A
HA
Schouten
J P
JP
Vonk
J M
JM
Koëter
G H
GH
Postma
D S
DS
D000368:Aged; D000893:Anti-Inflammatory Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D016535:Bronchial Hyperreactivity / Q000276:immunology / Q000503:physiopathology*; D001985:Bronchial Provocation Tests; D019819:Budesonide / Q000008:administration & dosage / Q000627:therapeutic use*; D004311:Double-Blind Method; D004359:Drug Therapy, Combination; D005541:Forced Expiratory Volume; D006801:Humans; D007073:Immunoglobulin E / Q000097:blood*; D008137:Longitudinal Studies; D008173:Lung Diseases, Obstructive / Q000188:drug therapy / Q000276:immunology / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D011239:Prednisolone / Q000008:administration & dosage / Q000627:therapeutic use
D000893:Anti-Inflammatory Agents; D007073:Immunoglobulin E; D019819:Budesonide; D011239:Prednisolone