The Effect of Lavender Aromatherapy on Cognitive Function in Older Adults With Mild Cognitive Impairment

The intervention protocol was established as follows: Based on the elderly participant's usual bedtime, the time of going to bed was recorded. The participant was instructed to assume a comfortable sleeping position, use the graduated dropper provided with the essential oil bottle to measure 0.15 ml (approximately 3 drops; theoretically, 0.05 ml per drop) of diluted lavender essential oil, and drip it vertically onto the upper center of a cotton pad. The cotton pad was then pinned to the collar with a safety pin, and the participant was instructed to inhale the scent evenly for 30 minutes. Afterward, the intervention staff or caregiver will remove the cotton pad. The intervention will be conducted 5 days a week for 12 weeks.

Inclusion criteria

• The MCI mentioned in this study meets the diagnostic criteria proposed by the *Chinese Expert Consensus on the Diagnosis and Treatment of Alzheimer's Disease-Derived Mild Cognitive Impairment (2021)*: cognitive impairment reported by the patient or an informant, or identified by an experienced clinician; objective evidence of impairment in one or more cognitive domains, with episodic memory impairment being the most common; complex instrumental activities of daily living may be mildly impaired, but the ability to perform basic activities of daily living remains independent; the diagnostic criteria for dementia are not met.
• MoCA-Beijing version scores were adjusted for education level: ≤13 for junior high school education or below, ≤19 for high school education, and ≤24 for university education or above; MMSE score >24; ADL score <23.
• Age between 60 and 79 years.
• Normal olfactory function assessed using the "Sniffin' Sticks" test.
• Ability to communicate normally and complete cognitive assessments.
• Residing in a senior care facility with no plans to leave within the next 12 weeks.

Exclusion criteria

• Presence of other conditions known to affect cognitive function, such as psychiatric disorders (e.g., schizophrenia, depression).
• History of asthma or any allergic conditions.
• Use of any prescription medications that may impact cognitive function (including psychotropic drugs and others)