24S-Hydroxycholesterol Is Associated with Agitation Severity in Patients with Moderate-to-Severe Alzheimer's Disease: Analyses from a Clinical Trial with Nabilone.

Abstract

BACKGROUND:

Agitation is a prevalent and difficult-to-treat symptom of Alzheimer's disease (AD). The endocannabinoid system (ECS) has been a target of interest for the treatment of agitation. However, ECS signaling may interact with AD-related changes in brain cholesterol metabolism. Elevated brain cholesterol, reflected by reduced serum 24-S-hydroxycholesterol (24S-OHC), is associated with reduced membrane fluidity, preventing ligand binding to cannabinoid receptor 1.

OBJECTIVE:

To assess whether 24S-OHC was associated with agitation severity and response to nabilone.

METHODS:

24S-OHC was collected from AD patients enrolled in a clinical trial on nabilone at the start and end of each phase. This allowed for the cross-sectional and longitudinal investigation between 24S-OHC and agitation (Cohen Mansfield Agitation Inventory, CMAI). Post-hoc analyses included adjustments for baseline standardized Mini-Mental Status Exam (sMMSE), and analyses with CMAI subtotals consistent with the International Psychogeriatric Association (IPA) definition for agitation (physical aggression and nonaggression, and verbal aggression).

RESULTS:

24S-OHC was not associated with CMAI scores cross-sectionally or longitudinally, before and after adjusting for baseline sMMSE. However, 24S-OHC was associated with greater CMAI IPA scores at baseline (F(1,36) = 4.95, p = 0.03). In the placebo phase only, lower 24S-OHC at baseline was associated with increases in CMAI IPA scores (b = -35.2, 95% CI -65.6 to -5.0, p = 0.02), and decreases in 24S-OHC were associated with increases in CMAI IPA scores (b = -20.94, 95% CI -57.9 to -4.01, p = 0.03).

CONCLUSION:

24S-OHC was associated with agitation severity cross-sectionally, and longitudinally in patients with AD. However, 24S-OHC did not predict treatment response, and does not change over time with nabilone.

• Authors: Myuri Ruthirakuhan, Nathan Herrmann, Ana C Andreazza, Nicolaas Paul L G Verhoeff, Damien Gallagher, Sandra E Black, Alex Kiss, Krista L Lanctôt
• Journal: Journal of Alzheimer's disease : JAD (J Alzheimers Dis) Vol. 71 Issue 1 Pg. 21-31 ( 2019) ISSN: 1875-8908 [Electronic] Netherlands
• PMID: 31322567 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Anti-Anxiety Agents
• Hydroxycholesterols
• nabilone
• 24-hydroxycholesterol
• Dronabinol

Topics

• Aged, 80 and over
• Alzheimer Disease (complications, psychology)
• Anti-Anxiety Agents (therapeutic use)
• Cross-Sectional Studies
• Dronabinol (analogs & derivatives, therapeutic use)
• Female
• Humans
• Hydroxycholesterols (blood, metabolism)
• Longitudinal Studies
• Male
• Psychomotor Agitation (blood, drug therapy, metabolism)
• Treatment Outcome