Clinical Briefs: Common Sage for Alzheimer’s Disease
With Comments from Russell H. Greenfield, MD
Source: Akhondzadeh S, et al. Salvia officinalis extract in the treatment of patients with mild to moderate Alzheimer’s disease: A double blind, randomized and placebo-controlled trial. J Clin Pharm Ther 2003;28: 53-59.
Goal: To assess the safety and efficacy of an extract of Salvia officinalis for people with Alzheimer’s disease (AD).
Design: Double-blind, randomized, placebo-controlled parallel study.
Subjects: Thirty-nine Iranian subjects (aged 65-80 years) randomized to trial intervention over four months (30 included in final analysis); all met criteria for the diagnosis of AD and had experienced a gradual decline in cognitive function over at least six months. All subjects had a score of ³ 12 on the cognitive subscale of the Alzheimer’s Disease Assessment Scale (ADAS-cog) and £ 2 on the Clinical Dementia Rating Sum of Boxes scale (CDR-SB).
Methods: All medications being used to treat dementia were discontinued. Subjects were randomized to receive 60 drops per day of either an extract of S. officinalis (1 kg dried leaf to 1 L of alcohol) or placebo. ADAS-cog and CDR-SB were administered to patients at baseline and every two weeks by a neurologist.
Results: There were no significant differences between the two groups at baseline. At trial’s end, those who received S. officinalis had significantly better scores on ADAS-cog and CDR-SB than subjects in the placebo group. While not objectively measured, agitation appeared to be more prevalent in those receiving placebo. Side effects related to use of S. officinalis were related to cholinergic stimulation.
Conclusion: An extract of S. officinalis may benefit people with mild-to-moderate AD.
Study strengths: Statistics employed; close follow-up; the study was coordinated by and the herb obtained from The Institute of Medicinal Plants.
Study weaknesses: The alcoholic extract and volatile oil of S. officinalis both contain thujones, ingestion of which can be associated with significant side effects (including tachycardia, confusion, and seizures), a point not made in the article; small number of subjects with significant dropout rate (9/39); 103 patients were initially screened for entrance into the study, but it is unclear why the other 64 people were not enrolled; unknown whether subjects had been exposed to agents like donepezil in the past and for how long; inexact reporting of method of administration (60 drops per day—all at once or divided doses?); short trial duration.
Of note: Five people dropped out of the placebo arm, and four dropped out of the active arm of the trial.
Did you know? AD affects close to 20 million people worldwide and is the leading cause of disability in the elderly. The incidence of AD increases from 0.5% at age 65 to 8.0% by age 85. Salvia officinalis also is known as common sage.
Clinical import: This study, although intriguing, has significant methodologic shortcomings that limit applicability. Most importantly, it does little to quell concerns over the safety of taking an extract of sage internally for a prolonged period of time. It is far too early to recommend the use of S. officinalis to patients with mild-to-moderate AD either alone or in combination with other agents.
An increase in the prevalence of AD can be expected in our aging population, and although any intervention that offers hope for slowing the disease process merits further study, safety must first be established.
What to do with this article: Remember that you read the abstract.
Dr. Greenfield is Medical Director, Carolinas Integrative Health, Carolinas HealthCare System, Charlotte, NC.