Effect of olfactory stimulation with essential oils on cardiovascular reactivity during the moving beans task in stroke patients with anxiety

Objective To investigate the effect of olfactory stimulation with essential oils on cardiovascular reactivity during the “moving beans” rehabilitation task in stroke patients with anxiety. Methods Twenty-eight stroke patients participated in this study. Blood pressure and heart rate were measured before and after finger movement tasks (e.g., moving beans and the Purdue pegboard test). Olfactory stimulation with lavender oil, grapefruit oil, and distilled water were conducted during finger tasks. Anxiety was assessed using the State Trait Anxiety Inventory (STAI)-Y2 before the finger movement tasks. Results There were no significant changes in blood pressure or heart rate activity in both finger movement tasks when stimulation of lavender oil, grapefruit oil, and distilled water was applied. However, the change values of Δ diastolic blood pressure (DBP) associated with the moving beans task indicated a significant interaction between olfactory stimulations and the groups of STAI-Y2 scores (high vs low) (p = 0.03), without main effects in the olfactory stimulations and the groups of STAI-Y2 scores. Conclusion Olfactory stimulation with lavender and grapefruit oil may repress the exaggerated DBP response during the moving beans task in stroke patients with higher levels of trait anxiety symptoms.