Cranial osteopathic treatment and stress-related effects on autonomic nervous system measured by salivary markers: A pilot study

Background: Variations in the concentration of salivary alpha amylase (sAA) may indicate a change in the autonomic nervous system functionality. In osteopathic medicine it has long been stated that the osteopathic manipulative treatment (OMT) can modulate the autonomic nervous system. Studies carried out on the compression of the fourth ventricle (CV4) have shown a positive effect in reducing the sympathetic tone. The goal of this pilot study is measuring the physiological response of the sAA levels after CV4 technique. Methods: 90 subjects were randomly assigned to a sham, a control or a CV4 group. Randomization accounted for sex and score in the STAI-2 (form Y) questionnaire. Each subject completed the STAI-1 (form Y) questionnaire to evaluate the anxiety of the moment. sAA activity and saliva flow rate were measured. Saliva was collected before, immediately after and 30 min after treatment. Results: Within group analysis revealed that sAA activity increased significantly immediately after the technique application only in the CV4 group (p = 0,05). Between groups analysis show a significant difference of the sAA activity in the CV4 group respect the control group (p < 0,05), but no significant difference between CV4 and sham group (p > 0,05). The effect in the CV4 group after the intervention is highly variable and appeared to be related to the level of stress measured with the STAI-Y1 questionnaire (p = 0,002). Conclusions: This study shows a positive effect of the CV4 procedure on sAA activity even if not significantly different from the sham procedure, probably due to the confounding effect of stress variability between groups. (C) 2020 Elsevier Ltd. All rights reserved.