The effects of osteopathy in the cranial field on stress as measured by salivary cortisol levels
Vreede, Jeanette Elizabeth
Permanent link to Research Bank record:http://hdl.handle.net/10652/1608
Introduction: Stress, both physical and psychological, has the ability to influence physical health outcomes. Within Osteopathy in the Cranial Field (OCF) there are claims that OCF can be used to effectively treat stress. The aim of this pilot study was to investigate the effect of an OCF session on salivary cortisol and subject selfreports of stress when compared to a sham procedure. Methods: A single blind, placebo-controlled, cross-over experimental design was used. At the same time on consecutive days, participants who were naïve to OCF received two 20-minute interventions, either cranial treatment or sham, administered in random order to which both practitioners and were blinded, following a mental computation task, given after initial measurements and before interventions, known to induce psychological stress. Salivary cortisol and self-reported stress scores (SRSS) were collected before and after the stress task (Initial and Pre-Intervention samples) and after each intervention (Post-Intervention sample). Results: Ten participants (5 male; 5 female) with a mean ± SD age of 36.9 ± 8.0 years completed the study. Group data analysis identified trivial differences in salivary cortisol levels between Initial, Pre-intervention and Post-intervention samples (p = 0.37) and between cranial and sham interventions (p = 0.64). Analysis of SRSS revealed large differences between Initial, Pre-intervention and Post-intervention samples (p<0.001), but trivial differences between sham and cranial interventions (p = 0.89). After the sham intervention five participants had a ‘moderate to large’ increase in salivary cortisol, two had a ‘trivial’ to ‘small’ change in cortisol, and five had a 55 ‘moderate’ to ‘large’ decrease in cortisol. For the cranial intervention three individuals experienced a ‘moderate’ to ‘large’ increase in cortisol, two had a ‘trivial’ to ‘small’ change in cortisol and five had a ‘moderate’ to ‘large’ decrease in cortisol. The mental computation task did not induce a consistent cortisol stress response for either intervention (Intraclass r = 0.04; Pearson’s r = 0.11), and there was a weak correlation between stress ratings and salivary cortisol levels (Pearson’s r = 0.25; p = 0.04). Conclusion: Preliminary data analysis indicates that whilst participants reported they were stressed by the computation task, the task failed to stress them reliably. Although participants reported less stress after both the sham and the OCF intervention, salivary cortisol levels did not change, nor was there any difference in either participant-reported stress rating or cortisol levels between the cranial and sham interventions. Individually, most participants had some change in salivary cortisol in response to both interventions (increase or decrease), but there was no evidence to indicate that the cranial intervention decreased cortisol levels more than the sham intervention. This study failed to find evidence to support claims that OCF can have a positive effect on psychological stress.