Evaluation of the effect of aroma oil as a bath salt on cognitive function

Abstract

Background Aromatherapy is a non‐pharmacological therapy for the improvement of dementia symptoms. This study aimed to assess the effects of aroma oil as a bath salt on cognitive function, olfactory function and sleep quality. Methods This was a randomised controlled trial. Overall, 49 patients were able to provide consent, and 35 were finally analysed (Alzheimer's disease: 10, mild cognitive impairment: 25). The patients were randomly assigned to use 0.1%, 0.5% or 1% aroma bath salt. During daily bathing, bath salt was added to the bath water, and the subjects remained in the bathroom for ≥10 min. The intervention period was 24 weeks, and the observation periods were 4 weeks before and after using the aroma bath salt. We performed the Touch Panel‐type Dementia Assessment Scale (TDAS), the Odour Stick Identification Test for Japanese (OSIT‐J) and the Japanese version of the Pittsburgh Sleep Quality Index (PSQI‐J) five times during the before and after observation periods and after the 12‐week intervention. Results There were no significant changes in the TDAS, OSIT‐J and PSQI‐J scores before and after the intervention in all groups. Moreover, there were no significant differences in the TDAS, OSIT‐J and PSQI‐J scores between the groups before and after the intervention. In the correlation analysis of changes in the TDAS and other tests during the intervention period, significant associations between TDAS and sleep latency and sleep disturbances, which are sub‐items of PSQI‐J, were observed in the use of 0.1% aroma bath salt group. Conclusions The use of aroma bath salt was not associated with improvement in cognitive function, olfactory function or sleep quality. However, sleep‐related aspects were associated with changes in cognitive function before and after use of aroma bath salt, which suggested that there is a link between improvements in sleep and that in cognitive function.

Cinnamomum verum J. Presl. Bark essential oil: in vitro investigation of anti-cholinesterase, anti-BACE1, and neuroprotective activity

“…(Myristicaceae), and Crocus sativus L. (Iridaceae) has been traditionally recommended for the treatment of memory loss in Iranian traditional medicine (ITM) [ 19 ]. On the other hand, non-pharmacological approaches have been developed for the improvement of cognitive problems [ 20 , 21 ] and in this respect, aromatherapy has been widely considered as a strong tool [ 22 ]. In different studies, the combination of therapies has depicted significant results in improving memory, quality of life, and treatment of other complications in patients with AD [ 23 , 24 ].…”

Pharmacological and non‐pharmacological interventions to enhance sleep in mild cognitive impairment and mild Alzheimer's disease: A systematic review

“…Kouzuki et al. ( 2020 ) reported minor dermatological side effects following the use of bath salts. No significant adverse events were reported across the remaining included studies.…”

“…Kouzuki et al. ( 2020 ) conducted a randomised controlled trial of aroma oil as a bath salt, to determine its effect on cognition, olfactory function and subjective measures of sleep as determined by PSQI‐J (Japanese version of PSQI). 35 participants with MCI or AD were randomised to three strengths of aroma oils (0.1%, 0.5% and 1%) with bathing performed nightly after 18:00 hr for 24 weeks.…”

Non-Pharmacological Treatments of Neuropsychiatric Symptoms in Mild Cognitive Impairment

“…However, a study in individuals with MCI and dementia found no improvement in any measured outcomes, including sleep and cognition. 94 There are very few investigations in individuals with MCI and evidence in dementia is conflicting and of low-quality. 95 There is no convincing evidence to date that aromatherapy has an impact on NPS in MCI.…”