In a consensus statement recently published by the British Association for Psychopharmacology,1 the use of aromatherapy as an adjunct to the pharmacological treatment of dementia is supported by one of the highest level of scientific evidence – evidence from randomized controlled trials.
A number of recent, controlled studies have shown that aromatherapy (the therapeutic use of pure plant essential oils) can be useful in the management of patients with dementia: lavender (Lavandula angustifolia or Lavandula officinalis) and lemon balm (Melissa officinalis) are two essential oils of particular interest in this area. The aim of the article by Holmes & Ballard,2 summarized here, was to review published reports of the efficacy of aromatherapy for the treatment of behavioural problems in people with dementia.
The results of these studies are interesting as their findings cannot be dismissed as merely resulting from the placebo effect of a pleasant-smelling fragrance: as the authors note, most people with severe dementia will have lost any meaningful sense of smell because of the early loss of olfactory neurons.3 Indeed, the pharmacological mechanism by which aromatherapy produces its effects is not thought to involve any perception of odour. Instead, the active compounds are thought to enter the body (by absorption through the lungs or olfactory mucosa) and be delivered to the brain via the bloodstream, where they elicit direct actions.
Aromatherapy studies in patients with dementia A large number of small, uncontrolled case studies have demonstrated the efficacy of inhaled and/or topical lavender oil in this setting. In summary, these studies have shown lavender oil to improve sleep patterns,4-7 and to improve behaviour.8,9
Although only a few controlled studies have investigated the potential use of aromatherapy for the management of behavioural problems in people with dementia, the results have been positive. A single-blind, case-controlled study investigated the effects of lavender essential oil on disordered behaviour in patients with severe dementia.10,11 Patients (n=21) were randomized to receive massage only, lavender essential oil administered as massage or lavender oil administered via inhalation plus conversation. Of the three patient groups, those receiving the essential oil in a massage showed a significantly greater reduction in the frequency of excessive motor behaviour.
In a small (n=15) double-blind, placebo-controlled, crossover trial in patients with severe dementia on an NHS care ward,11,12 2% lavender oil was administered in an aroma diffuser on the ward for a 2-hour period, alternated with placebo (water) every other day, for a total of ten treatment sessions. According to the group median Pittsburgh Agitation Scale score, treatment with lavender aromatherapy reduced agitated behaviour significantly (p=0.016) in patients with severe dementia compared with placebo, with 60% of patients experiencing some benefit. No adverse events were reported and compliance with therapy was 100%.
In a crossover study,13 56 elderly patients with moderate to severe dementia were massaged with a cream containing a blend of four essential oils (lavender, sweet marjoram, patchouli and vetiver) or cream alone five times a day for 8 weeks. Behavioural problems and resistance to care were significantly lower in patients who received the cream containing the essential oils compared with those who received the cream alone.