Showing posts with label placebo therapy. Show all posts
Showing posts with label placebo therapy. Show all posts

Monday, 15 April 2013

Aromatherapy: A pseudoscience ?

Aromatherapy usually involves the application of diluted essential (volatile) oils via a gentle massage of the body surface. The chemist Rene-Maurice Gattefosse (1881-1950) coined the term ‘aromatherapy’ after experiencing that lavender oil helped to cure a severe burn of his hand. In 1937, he published a book on the subject: Aromathérapie: Les Huiles Essentielles, Hormones Végétales. Later, the French surgeon Jean Valnet used essential oils to help heal soldiers’ wounds in World War II.
Aromatherapy is currently one of the most popular of all alternative therapies. The reason for its popularity seems simple: it is an agreeable, luxurious form of pampering. Whether it truly merits to be called a therapy is debatable.
The authors of this systematic review stated that they wanted to critically assess the effect of aromatherapy on the psychological symptoms as noted in the postmenopausal and elderly women. They conducted electronic literature searches and fount 4 trials that met their inclusion criteria. The findings demonstrated that aromatherapy massage significantly improves psychological symptoms in menopausal, elderly women as compared to controls. In one trial, aromatherapy massage was no more effective than the untreated group regarding their experience of symptoms such as nervousness.
The authors concluded that aromatherapy may be beneficial in attenuating the psychological symptoms that these women may experience, such as anxiety and depression, but it is not considered as an effective treatment to manage nervousness symptom among menopausal women. This finding should be observed in light of study limitations.
In the discussion section, the authors state that to the best of our knowledge, this is the first meta-analysis evaluating the effect of aromatherapy on the psychological symptoms. I believe that they might be mistaken. Here are two of my own papers (other researchers have published further reviews) on the subject:
  1. Aromatherapy is the therapeutic use of essential oil from herbs, flowers, and other plants. The aim of this overview was to provide an overview of systematic reviews evaluating the effectiveness of aromatherapy. We searched 12 electronic databases and our departmental files without restrictions of time or language. The methodological quality of all systematic reviews was evaluated independently by two authors. Of 201 potentially relevant publications, 10 met our inclusion criteria. Most of the systematic reviews were of poor methodological quality. The clinical subject areas were hypertension, depression, anxiety, pain relief, and dementia. For none of the conditions was the evidence convincing. Several SRs of aromatherapy have recently been published. Due to a number of caveats, the evidence is not sufficiently convincing that aromatherapy is an effective therapy for any condition.
  2. Aromatherapy is becoming increasingly popular; however there are few clear indications for its use. To systematically review the literature on aromatherapy in order to discover whether any clinical indication may be recommended for its use, computerised literature searches were performed to retrieve all randomised controlled trials of aromatherapy from the following databases: MEDLINE, EMBASE, British Nursing Index, CISCOM, and AMED. The methodological quality of the trials was assessed using the Jadad score. All trials were evaluated independently by both authors and data were extracted in a pre-defined, standardised fashion. Twelve trials were located: six of them had no independent replication; six related to the relaxing effects of aromatherapy combined with massage. These studies suggest that aromatherapy massage has a mild, transient anxiolytic effect. Based on a critical assessment of the six studies relating to relaxation, the effects of aromatherapy are probably not strong enough for it to be considered for the treatment of anxiety. The hypothesis that it is effective for any other indication is not supported by the findings of rigorous clinical trials.
Omitting previous research may be odd, but it is not a fatal flaw. What makes this review truly dismal is the fact that the authors fail to discuss the poor quality of the primary studies. They are of such deplorable rigor that one can really not draw any conclusion at all from them. I therefore find the conclusions of this new paper unacceptable and think that our statement (even though a few years old) is much more accurate: the evidence is not sufficiently convincing that aromatherapy is an effective therapy for any condition.