Stress-related Problems
Conditions
Keywords
aromatherapy, stress, older adults, stress-related change
Brief summary
The study purpose is to evaluate efficacy of stress-reducing aromatherapy and learn about how aromatherapy works.
Detailed description
The study purpose is to evaluate efficacy of stress-reducing aromatherapy and learn about how aromatherapy works by comparing participants' physiologic responses to laboratory challenge tasks with and without experiencing aromatherapy.
Interventions
OTHERaroma
Comparison of known stress reducing aroma to placebo aromas without stress-reducing effects
Sponsors
Oregon Health and Science University
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
PREVENTION
Masking
SINGLE (Outcomes Assessor)
Eligibility
Sex/Gender
ALL
Age
50 Years to 85 Years
Healthy volunteers
Yes
Inclusion criteria
* in good physical and cognitive health * reporting moderate level of stress * able to perceive aromas * able to understand and follow study instructions
Exclusion criteria
* taking medications affecting central nervous system (CNS) function or physiologic measures (e.g. steroids or neuroleptics) * reporting smell sensitivities or allergies * smoking presently or in the past less than one year prior to enrollment
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Percent of Baseline Level of Salivary Cortisol | assessed at baseline (60 min prior to aroma exposure and stress), stress battery (30 min after aroma exposure and during stress), post-stress (60 min after completing stress battery) | Percent of baseline level of salivary cortisol (values greater than baseline indicate increased stress) |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Electroencephalography (EEG) Frontal Asymmetry | assessed at baseline (60 min prior to aroma exposure and stress), at the onset of aromatherapy exposure, stress battery (30 min after aroma exposure and during stress), post-stress (60 min after completing stress battery) | EEG frontal asymmetry (FA) is used to assess emotional state. EEG FA processing was completed by averaging local reference EEG filtered offline from 0.1 to 70 Hz (with 60 Hz notch filter). 5-min data periods during each time were segmented into 2 seconds epochs, and the semi-automatic artifact rejection was applied. The remaining artifact-free epochs were subjected to Fast Fourier Transform (FFT) . The power spectra for individual epochs were averaged, and the measures of EEG spectral density were obtained for alpha band (8 -12.99 Hz). Square root values of power were used, and frontal hemispheric asymmetry was calculated as ((L-R)/(L+R))\*100, where L and R are square root values at the homologous left and right hemisphere sites (using local average reference values at F3 and F4). With this calculation, FA negative values reflect lower alpha power (higher activation) in the left hemisphere linked to a more positive mood. This is a unit-free measure. |
| Cognitive Performance: Percent Change From Baseline in Digit Span Backward Task Score | Baseline (60 min prior to aroma exposure and stress), post-stress (60 min after completing stress battery) | Percent change from baseline in cognitive performance score on the Digit Span Backward (DSB) task. DSB scores range from 0 to 16, with greater scores indicative of better cognitive function. Positive change from baseline indicates better functioning. |
Countries
United States
Participant flow
Recruitment details
212 people potentially interested in the study were evaluated for eligibility between 2010 and 2012. The potential participants were referred by clinicians from the university sleep clinic or learned about the study from the IRB-approved study information posted around the university, or published on social media.
Participants by arm
| Arm | Count |
|---|---|
| Stress Reducing Aroma aroma with reported stress reducing effects
aroma: Comparison of known stress reducing aroma to placebo aromas without stress-reducing effects | 31 |
| Placebo Aroma 1 aroma: Comparison of known stress reducing aroma to placebo aromas without stress-reducing effects.
Coconut aroma with pleasant odor but no reported stress-reducing effects | 31 |
| Placebo Aroma 2 aroma: Comparison of known stress reducing aroma to placebo aromas without stress-reducing effects.
Distilled water: substance with no odor or stress-reducing effects | 30 |
| Total | 92 |
Baseline characteristics
| Characteristic | Stress Reducing Aroma | Placebo Aroma 1 | Placebo Aroma 2 | Total |
|---|---|---|---|---|
| Age, Continuous | 58.9 years STANDARD_DEVIATION 6.6 | 57.9 years STANDARD_DEVIATION 6 | 57.3 years STANDARD_DEVIATION 5.9 | 58.0 years STANDARD_DEVIATION 6 |
| Region of Enrollment United States | 31 participants | 31 participants | 31 participants | 92 participants |
| Sex: Female, Male Female | 24 Participants | 26 Participants | 23 Participants | 73 Participants |
| Sex: Female, Male Male | 7 Participants | 5 Participants | 7 Participants | 19 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk | EG002 affected / at risk |
|---|---|---|---|
| deaths Total, all-cause mortality | 0 / 31 | 0 / 31 | 0 / 30 |
| other Total, other adverse events | 1 / 31 | 0 / 31 | 0 / 30 |
| serious Total, serious adverse events | 0 / 31 | 0 / 31 | 0 / 30 |
Outcome results
Primary
Percent of Baseline Level of Salivary Cortisol
Percent of baseline level of salivary cortisol (values greater than baseline indicate increased stress)
Time frame: assessed at baseline (60 min prior to aroma exposure and stress), stress battery (30 min after aroma exposure and during stress), post-stress (60 min after completing stress battery)
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Stress Reducing Aroma:Lavender | Percent of Baseline Level of Salivary Cortisol | stress battery | 170.8 percentage of baseline cortisol level | Standard Error 31.3 |
| Stress Reducing Aroma:Lavender | Percent of Baseline Level of Salivary Cortisol | post-stress | 106.4 percentage of baseline cortisol level | Standard Error 70.6 |
| Detectable Placebo Aroma: Coconut | Percent of Baseline Level of Salivary Cortisol | stress battery | 224.7 percentage of baseline cortisol level | Standard Error 30.8 |
| Detectable Placebo Aroma: Coconut | Percent of Baseline Level of Salivary Cortisol | post-stress | 187.3 percentage of baseline cortisol level | Standard Error 69.5 |
| Undetectable Placebo Aroma: Water | Percent of Baseline Level of Salivary Cortisol | stress battery | 274.7 percentage of baseline cortisol level | Standard Error 31.9 |
| Undetectable Placebo Aroma: Water | Percent of Baseline Level of Salivary Cortisol | post-stress | 131.2 percentage of baseline cortisol level | Standard Error 71.9 |
Comparison: The null hypothesis stated that there were no differences between the groups in cortisol level trajectory over time.p-value: 0.005ANCOVA
Secondary
Cognitive Performance: Percent Change From Baseline in Digit Span Backward Task Score
Percent change from baseline in cognitive performance score on the Digit Span Backward (DSB) task. DSB scores range from 0 to 16, with greater scores indicative of better cognitive function. Positive change from baseline indicates better functioning.
Time frame: Baseline (60 min prior to aroma exposure and stress), post-stress (60 min after completing stress battery)
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Stress Reducing Aroma:Lavender | Cognitive Performance: Percent Change From Baseline in Digit Span Backward Task Score | 15.24 Percent change from baseline in DSB task | Standard Deviation 4.09 |
| Detectable Placebo Aroma: Coconut | Cognitive Performance: Percent Change From Baseline in Digit Span Backward Task Score | -.37 Percent change from baseline in DSB task | Standard Deviation 4.09 |
| Undetectable Placebo Aroma: Water | Cognitive Performance: Percent Change From Baseline in Digit Span Backward Task Score | 0.92 Percent change from baseline in DSB task | Standard Deviation 4.15 |
p-value: 0.01ANCOVA
Secondary
Electroencephalography (EEG) Frontal Asymmetry
EEG frontal asymmetry (FA) is used to assess emotional state. EEG FA processing was completed by averaging local reference EEG filtered offline from 0.1 to 70 Hz (with 60 Hz notch filter). 5-min data periods during each time were segmented into 2 seconds epochs, and the semi-automatic artifact rejection was applied. The remaining artifact-free epochs were subjected to Fast Fourier Transform (FFT) . The power spectra for individual epochs were averaged, and the measures of EEG spectral density were obtained for alpha band (8 -12.99 Hz). Square root values of power were used, and frontal hemispheric asymmetry was calculated as ((L-R)/(L+R))\*100, where L and R are square root values at the homologous left and right hemisphere sites (using local average reference values at F3 and F4). With this calculation, FA negative values reflect lower alpha power (higher activation) in the left hemisphere linked to a more positive mood. This is a unit-free measure.
Time frame: assessed at baseline (60 min prior to aroma exposure and stress), at the onset of aromatherapy exposure, stress battery (30 min after aroma exposure and during stress), post-stress (60 min after completing stress battery)
Population: All participants had EEG recordings during their visit. However, some EEG data were lost due to electrode malfunction or unusable due to presence of too much noise. The data loss was similar in all study groups.
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Stress Reducing Aroma:Lavender | Electroencephalography (EEG) Frontal Asymmetry | Aromatherapy exposure onset | .005 unitless | Standard Error 0.028 |
| Stress Reducing Aroma:Lavender | Electroencephalography (EEG) Frontal Asymmetry | Stress battery | .031 unitless | Standard Error 0.027 |
| Stress Reducing Aroma:Lavender | Electroencephalography (EEG) Frontal Asymmetry | Baseline | .013 unitless | Standard Error 0.027 |
| Stress Reducing Aroma:Lavender | Electroencephalography (EEG) Frontal Asymmetry | Post-stress | .009 unitless | Standard Error 0.026 |
| Detectable Placebo Aroma: Coconut | Electroencephalography (EEG) Frontal Asymmetry | Aromatherapy exposure onset | -.014 unitless | Standard Error 0.027 |
| Detectable Placebo Aroma: Coconut | Electroencephalography (EEG) Frontal Asymmetry | Baseline | .006 unitless | Standard Error 0.026 |
| Detectable Placebo Aroma: Coconut | Electroencephalography (EEG) Frontal Asymmetry | Stress battery | -.001 unitless | Standard Error 0.026 |
| Detectable Placebo Aroma: Coconut | Electroencephalography (EEG) Frontal Asymmetry | Post-stress | .037 unitless | Standard Error 0.025 |
| Undetectable Placebo Aroma: Water | Electroencephalography (EEG) Frontal Asymmetry | Stress battery | .066 unitless | Standard Error 0.029 |
| Undetectable Placebo Aroma: Water | Electroencephalography (EEG) Frontal Asymmetry | Baseline | .036 unitless | Standard Error 0.028 |
| Undetectable Placebo Aroma: Water | Electroencephalography (EEG) Frontal Asymmetry | Aromatherapy exposure onset | .064 unitless | Standard Error 0.029 |
| Undetectable Placebo Aroma: Water | Electroencephalography (EEG) Frontal Asymmetry | Post-stress | .089 unitless | Standard Error 0.027 |