The study protocol of a blinded randomised-controlled cross-over trial of lavender oil as a treatment of behavioural symptoms in dementia

The agitated behaviours that accompany dementia (e.g. pacing, aggression, calling out) are stressful to both nursing home residents and their carers and are difficult to treat. Increasingly more attention is being paid to alternative interventions that are associated with fewer risks than pharmacology. Lavandula angustifolia (lavender) has been thought, for centuries, to have soothing properties, but the existing evidence is limited and shows mixed results. The aim of the current study is to test the effectiveness of topically applied pure lavender oil in reducing actual counts of challenging behaviours in nursing home residents. We will use a blinded repeated measures design with random cross-over between lavender oil and placebo oil. Persons with moderate to severe dementia and associated behavioural problems living in aged care facilities will be included in the study. Consented, willing participants will be assigned in random order to lavender or placebo blocks for one week then switched to the other condition for the following week. In each week the oils will be applied on three days with at least a two-day wash out period between conditions. Trained observers will note presence of target behaviours and predominant type of affect displayed during the 30 minutes before and the 60 minutes after application of the oil. Nursing staff will apply 1 ml of 30% high strength essential lavender oil to reduce the risk of missing a true effect through under-dosing. The placebo will comprise of jojoba oil only. The oils will be identical in appearance and texture, but can easily be identified by smell. For blinding purposes, all staff involved in applying the oil or observing the resident will apply a masking cream containing a mixture of lavender and other essential oils to their upper lip. In addition, nursing staff will wear a nose clip during the few minutes it takes to massage the oil to the resident's forearms. If our results show that the use of lavender oil is effective in reducing challenging behaviours in individuals with dementia, it will potentially provide a safer intervention rather than reliance on pharmacology alone. The study's findings will translate easily to other countries and cultures. Australian New Zealand Clinical Trials Registry - ACTRN 12609000569202.