Aroma therapy for dementia

BACKGROUND: In the realm of dementia treatment aroma therapy has received great interest. In a population of patients not served by many mainstream drugs with great efficacy, complementary therapies are among few other options. The perceived low side effect profile of aromatherapy is also attractive to practitioners and family of patients with reduced verbal communication. As such it has been tried for many symptoms of dementia; to reduce disturbed behaviour (e.g. Brooker 1997), promote sleep (e.g. Wolfe 1996), and stimulate motivational behaviour (e.g. MacMahon 1998). Amongst the most distressing facets of dementia are the 'Behavioural and psychological symptoms in dementia' (BPSD). This manifestation of dementia often stresses the relationships between the patient, carers and family. This area has received particular interest in the larger aroma therapy trials. OBJECTIVES: To assess the efficacy of aroma therapy as an intervention for people with dementia. SEARCH STRATEGY: The Cochrane Dementia and Cognitive Improvement Group's Specialized Register was searched on 23 March 2008 to find all relevant trials using the terms: aroma therap*, complementary therap*, alternative therap* and essential oil*. The CDCIG Register contains records from major health care databases, grey literature sources and is updated regularly. Additionally, relevant journals were hand searched, and 'experts' in the field of complementary therapies and dementia contacted. SELECTION CRITERIA: All relevant randomized controlled trials (RCTs) were considered. A minimum length of trial and requirements for a follow-up were not included, and participants in included studies had a diagnosis of dementia of any type and severity. The review considered all trials using fragrance from plants defined as aroma therapy as an intervention with people with dementia. Several outcomes were considered in this review, including cognitive function, quality of life, and relaxation. DATA COLLECTION AND ANALYSIS: Titles and abstracts extracted by the searches were screened for their eligibility for potential inclusion in the review, which revealed four RCTs of aroma therapy for dementia that have been included in this review. None of these had published results in a form that we could use. However, individual patient data from one trial were obtained (Ballard 2002) and additional analyses performed. Analysis of co-variance was used for all outcomes, using a random effects model. MAIN RESULTS: Four studies have been included in this review; but none had data in a form that could be used. The additional analyses conducted using individual patient data from Ballard 2002 revealed a statistically significant treatment effect in favour of the aroma therapy intervention on measures of agitation and neuropsychiatric symptoms. AUTHORS' CONCLUSIONS: Aroma therapy showed benefit for people with dementia in the only trial that contributed data to this review, but it is important to note there were several methodological difficulties with this study. More well designed large-scale RCTs are needed before clear conclusions can be drawn on the effectiveness of aroma therapy. Additionally, several issues need to be addressed, such as whether different aroma therapy interventions are comparable and the possibility that outcomes may vary for different types of dementia.