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Flu Vaccination Exacerbates Asthma
"Randomized Placebo-Controlled Crossover Trial on Effect of
Inactivated Influenza Vaccine on Pulmonary Function in Asthma"
Lancet (01/31/98) Vol. 351, No. 9099, P. 326; Nicholson, Karl G.;
Nguyen-Van-Tam, Jonathan S.; Ahmed, Ala'eldin H.; et al.
British researchers report that there is a correlation
between pulmonary-function abnormalities and complications due to
flu vaccination, although the risk is quite small and the benefits
of vaccination outweigh the complications that may occur. The team
studied 262 adults in a double-blind, placebo-controlled crossover
study of 262 adults to evaluate the safety of flu vaccination in
asthma patients. Despite current guidelines, asthma patients often
do not receive annual flu shots, in part, due to concerns that the
vaccine will trigger exacerbations. For two weeks before the first
injection until two weeks after the second injection, the subjects
kept a record of daily peak expiratory flow (PEF), respiratory
symptoms, medication, medical consultations, and hospital
admissions. Of the 255 patients with paired data, 11 saw a
reduction in PEF greater than 20 percent, while eight had a decline
in PEF of more 30 percent. Only three of the placebo receiving
subjects had PEF reduction greater than 20 percent, and none had a
reduction greater than 30 percent. When the researchers excluded
subjects with colds--which can trigger exacerbations and may be
mistaken for vaccine-related adverse events--there was no
significant difference in PEF decline, although they said the
difference for PEF declines of more than 30 percent approached
significance.