[Circadian rhythm of parasympathetic nervous function in asthmatic children]

We examined the circadian rhythm of parasympathetic nervous function in asthmatic children. The subjects were 80 patients with asthma (mild 54 patients, moderate 15 patients and severe 11 patients) and 90 individuals in healthy children. All the patients underwent 24-electrocardiography in normal condition. We measured the %RR50 for hour and analyzed the rhythm using the single cosine fitting method, comparing the values of the Amplitude, the MESOR and the Acrophase in terms of the therapy and also the severity of asthma. Circadian rhythm disappeared in 9 of the 80 asthmatic children and was observed in all the individuals in the healthy children. The value of MESOR was lower in the asthmatic children than in the healthy children. There was no significant difference between the different severity or therapies in each group. In some asthmatic children, the circadian rhythm of parasympathetic nervous function disappeared, the parasympathetic nervous function was low in remission. It is suggested that the disorder of biologic rhythm is related to the pathogenesis of asthma.