Am. J. Respir. Crit. Care Med.,
Volume 162, Number 6, December 2000, 2048-2052
Effects of Specific Immunotherapy in Allergic Rhinitic
Individuals with Bronchial Hyperresponsiveness
ROSA D.
GREMBIALE,
LUIGI
CAMPOROTA,
SAVERIO
NATY,
CARMELINDO M. E.
TRANFA,
RATKO
DJUKANOVIC,
and
SERAFINO A.
MARSICO
Department of Experimental and Clinical Medicine, University of Catanzaro, Cantanzaro, Italy; and Division of University Medicine,
Southampton General Hospital, Southampton, United Kingdom
Allergic rhinitis can be associated with bronchial hyperresponsiveness (BHR), and carries an increased risk for the development of
asthma. The aim of this study was to evaluate the ability of specific
immunotherapy (SIT) to reduce the progression of allergic rhinitis
to asthma and prevent the associated increase in BHR. Forty-four
subjects monosensitized to Dermatophagoides pteronyssinus, with
perennial rhinitis and BHR to methacholine, were randomly assigned to receive SIT or placebo in a double-blind study conducted over a period of 2 yr. After 1 yr of treatment, a 2.88-fold increase in the provocative dose of methacholine producing a 20% decrease in FEV1 (PD20FEV1) was recorded in the SIT-treated group
(95% confidence interval [CI]: 3.98- to 2.09-fold; p < 0.001), with a further increase to fourfold at the end of Year 2 (95% CI: 2.9- to
5.7-fold; p < 0.001). At the end of the study, the methacholine PD20FEV1 was within the normal range in 50% of treated subjects (p < 0.0001), and was significantly higher in this group than in the
group receiving placebo (p < 0.0001). In contrast, no changes in
methacholine PD20FEV1 were found in the placebo group throughout the study. Although 9% of subjects given placebo developed
asthma, none of those treated with SIT did. This study suggests
that SIT, when administered to carefully selected, monosensitized
patients with perennial allergic rhinitis, reduces airway responsiveness in subjects with rhinitis, and may be an appropriate prophylactic treatment for rhinitic patients with hyperreactive airways.
