[The effect of ageing on the active sweat gland density in the dorsum of foot].

Focal sweating in the dorsum of foot induced by iontophoresis of 1% pilocarpine was quantitatively evaluated using silastic impression mold technique in 111 control subjects (71 men & 40 women), aged 14 to 89 years, to reveal the effect of aging on the density of active sweat glands. The subjects were divided into four groups (group I: aged 14 to 29 years, group II: aged 30 to 49 years, group III: aged 50 to 69 years, group IV: aged 70 to 89 years), and the difference of the density of active sweat glands was evaluated among the groups with Wilcoxon's rank sum test. It was statistically significant (p less than 0.001) between group II and III, and between group III and IV, but not significant between group I and II. Therefore, it was concluded that the density of active sweat glands decreases prominently after 50 years of age. The density of active sweat glands was not significantly different between man and woman in each group. In the regression analysis of the density of active sweat glands on age, the relationship (Density = -0.0178.Age2 + 232.6 (R2 = 0.54), p less than 0.0001) was obtained. Based on such relationship, the predicted density and the upper and lower limits of 95% confidence interval of the predicted density for each age were obtained. These results indicate that decrease of the density of active sweat glands due to ageing should be taken into consideration in the evaluation of the density of active sweat glands in the dorsum of foot among the patients with various neurological diseases.(ABSTRACT TRUNCATED AT 250 WORDS)