The reasons for the asthma epidemic are poorly understood. As the asthma pr
evalence follows the geographical and temporal trend of antibiotic use into
clinical medicine, we examined a possible association in a population-base
d study of 2,512 children age 5-14 in East Germany.
Wheezing was associated with increasing number of antibiotic courses (never
versus one time odds ratio 1.9, P=0.012, 2 to 5 times odds ratio 3.0, P<0.
001 and more than 5 times, odds ratio 6.9, P<0.001) which was also seen for
asthma diagnosis. The risk increased with earlier administration (never ve
rsus second year odds ratio 4.6, month 7-12 odds ratio 5.4 and birth until
month 6 odds ratio 7.9, all P<0.001). Also non pulmonary treatment indicati
on was associated with later wheezing (odds ratio 3.9, P<0.001).
The most likely possible explanation is reverse causation indicating that f
requent upper respiratory infections, an early symptom of asthma, are treat
ed with antibiotics. Antibiotic therapy could also be a proxy of another cl
osely associated genetic or environmental factor. The high dose effect, the
time dependency of the administration and the effect by non-pulmonary indi
cations raises the possibility that early antibiotic treatment could itself
be related to later asthma.