Sensory Enrichment for Older Adults

This study evaluates the efficacy of multi-odorant enrichment on cognitive skills, olfactory function, and quality of life.

Study Overview

• Status: Terminated
• Conditions: Cognitive Function
• Intervention / Treatment: Other: olfactory enrichment (essential oils)

Detailed Description

The purpose of this study is to explore sensory stimulation as a potential means of enhancing cognitive abilities. In mice, multi-odorant enrichment has been shown to increase neurogenesis in a critical memory pathway and thereby improve memory. In this clinical study, we will determine if a nightly sensory enrichment regimen using scents for 6 months can improve cognitive skills, as measured using a series of cognitive assessments and brain imaging in older adults. We also will determine if mood/mental state of mind or olfactory functioning improve following scent stimulation.

This study will enroll approximately 200 participants. Of the 200 participants in the study, 50 individuals, who are interested in participating, will have a functional Magnetic Resonance Imaging (fMRI) scan at the beginning and end of the study, which will be used to examine changes in the brain.

Participants will undergo cognitive assessments, computerized cognitive assessments, and olfactory function assessments. They will be randomly assigned to either an experimental or an active control group, and will be exposed to either a higher or lower concentration of essential oils nightly using a nebulizing fragrance diffuser, rotating through seven different scents, one per night. The exposures will continue for 6 months, after which the participants will return and undergo the same assessments conducted at the beginning of the study.

• Study Type: Interventional
• Enrollment (Actual): 110
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Blake A Miranda, BS; Phone Number: 949-824-0904; Email: bamirand@uci.edu
• Study Contact Backup: Name: Michael Leon, PhD; Phone Number: 949-237-3026; Email: mleon@uci.edu

Study Locations

• United States
  • California
    • Irvine, California, United States, 92697
      • University of California Irvine

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 60 years to 85 years (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

Description

Inclusion Criteria:

1. Are age 60-85, male or female
2. Have normal cognition (determined at first assessment with cognitive testing)
3. Speak/read/understand English fluently
4. Have visual and auditory acuity adequate for neuropsychological and computerized testing
5. Are in good general health with no disease(s) expected to interfere with the study
6. Are willing and able to participate for the duration of the study and in all study procedures
7. Are able to smell scents
8. Are willing to refrain from using scented candles, scented oils, or air fresheners while participating in the study

9. Are willing to travel to the research site for testing

   If interested in functional Magnetic Resonance Imaging (fMRI),

10. Are willing and able to participate in the fMRI scan.

Exclusion Criteria:

1. Have known fragrance sensitivities
2. Have asthma, allergies, or a fragrance sensitivity, which produces symptoms similar to those of an allergy, including runny nose, watery eyes, sneezing, or skin rash
3. Have a neurologic disease such as Parkinson's disease, multiple sclerosis, brain cyst, tumor or aneurysm
4. Have major health conditions such as uncontrolled diabetes mellitus, uncontrolled hypertension, nutritional deficiency or thyroid disease
5. Have significant psychiatric disorders such as schizophrenia, bipolar disorder, anxiety disorder, or attention-deficit hyperactivity disorder
6. Have cognitive impairment when tested at baseline (defined as a score on any neuropsychological test of 1.5 standard deviations or more outside the age norm)
7. Have had alcohol or substance abuse or dependence within the past 2 years (DSM-IV criteria)

8. Smoke cigarettes, e-cigarettes, cigars, marijuana, or any other substance that could produce an interfering odor for the study.

   If interested in functional Magnetic Resonance Imaging (fMRI),

9. MRI contraindications, (e.g. pacemakers, aneurysm clips, artificial heart valves, ear implants, metal fragments or foreign objects in the eyes, skin or body).

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Double

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Experimental group; Individuals in this group receive exposure to a higher concentration of essential oil fragrances nightly.	Other: olfactory enrichment (essential oils); Participants will be exposed to either a higher or lower concentration of essential oils nightly for two hours as they are going to sleep, using a nebulizing fragrance diffuser, rotating through seven different scents, one per night.
Placebo Comparator: Active control group; Individuals in this group receive exposure to a lower concentration of essential oil fragrances nightly.	Other: olfactory enrichment (essential oils); Participants will be exposed to either a higher or lower concentration of essential oils nightly for two hours as they are going to sleep, using a nebulizing fragrance diffuser, rotating through seven different scents, one per night.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Evaluation of behavioral pattern separation ability	Change in lure discrimination index on a computerized mnemonic discrimination task.	1) at Baseline and 2) after 6 months of intervention

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Evaluation of cognition	Change in cognitive ability will be measured using scores from a neuropsychological battery. For each subsection, a change score will be calculated using the difference between baseline and 6-month scores, and the change score will be compared between groups. Higher values indicate a better outcome.	1) at Baseline and 2) after 6 months of intervention
Evaluation of depression	Change in depression status using the Beck Depression Inventory.	1) at Baseline and 2) after 6 months of intervention
Evaluation of quality of life	Change in quality of life using the Farage Quality of Life questionnaire.	1) at Baseline and 2) after 6 months of intervention
Evaluation of olfactory function	Change from baseline score on the Sniffin' Sticks instrument to assess olfactory system functioning.	1) at Baseline and 2) after 6 months of intervention
Evaluation of change in brain structural connectivity	Change in perforant path integrity using functional Magnetic Resonance Imaging.	1) at Baseline and 2) after 6 months of intervention
Evaluation of change in brain structures	Change in thickness of entorhinal cortex using functional Magnetic Resonance Imaging.	1) at Baseline and 2) after 6 months of intervention

Collaborators and Investigators

• Sponsor: University of California, Irvine
• Collaborators: Procter and Gamble

Study record dates

Study Major Dates

• Study Start (Actual): March 8, 2019
• Primary Completion (Actual): June 30, 2021
• Study Completion (Actual): June 30, 2021

Study Registration Dates

• First Submitted: April 10, 2019
• First Submitted That Met QC Criteria: April 11, 2019
• First Posted (Actual): April 16, 2019

Study Record Updates

• Last Update Posted (Actual): March 24, 2023
• Last Update Submitted That Met QC Criteria: March 22, 2023
• Last Verified: February 1, 2023

More Information

Terms related to this study

• Keywords: Intervention; Life quality; Olfaction; Memory preservation; Age-related memory disorders
• Other Study ID Numbers: 2014-1078

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No