[The relationship between respiratory threshold to acetylcholine and prognosis for asthma]

Forty nine asthmatic children were studied to clarify the relationship between the respiratory threshold of acetylcholine (RT-Ach) and the prognosis for asthma. In those patients who had asthmatic attacks fewer than 60 days in the last year, there was a statistically significant relationship between RT-Ach and the number of the days of asthmatic attacks over the 6 and 12 month periods following the inhalation test. In the younger group (5-11 years old), there was a statistically significant relationship between RT-Ach and the number of the days of asthmatic attacks over the 6 and 12 month periods following the inhalation test. However, in the elder group (12-15 years old), no such relationship was recognized. In the elder group, the obstructive index, one of the indices of flow-volume curve, had a statistically significant correlation with the number of asthmatic attacks over the 6 and 12 month periods following the inhalation test. However in the younger group, no such relationship was recognized.