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Clinical scenario: A 67-year-old man presents with progressive development of symptoms of memory loss, apathy, decreased judgment, and change in mood during the past year. After physical examination and appropriate laboratory tests by a doctor, the patient in question is diagnosed with mild dementia and cognitive impairment, excluding organic or arteriosclerotic disorders. The patient would like to try phytotherapy and asks if herbal remedies might improve his condition. The provider searches The Cochrane Library and identifies the potentially relevant review "Ginkgo biloba for cognitive impairment and dementia," an abstract of which follows.
ABSTRACT
Background
Extracts of the leaves of the maidenhair tree, Ginkgo biloba, have long been used in China as a traditional medicine for various disorders of health. A standardized extract is widely prescribed in Germany and France for the treatment of a range of conditions, including memory and concentration problems, confusion, depression, anxiety, dizziness, tinnitus, and headache. The mechanisms of action are thought to reflect the action of several components of the extract and include increasing blood supply by dilating blood vessels, reducing blood viscosity, modification of neurotransmitter systems, and reducing the density of oxygen free radicals.
Objectives
The aim of the review is to assess the efficacy and safety of Ginkgo biloba for the treatment of patients with dementia or cognitive decline.
Search Strategy
Trials were identified on 26 june 2002 through a search of the CDCIG Specialized Register, which contains records from all main medical databases (MEDLINE, EMBASE, CINAHL, PsycINFO, SIGLE, LILACS), from ongoing trials databases such as Clinicaltrials.gov and Current Controlled Trials and many other sources. The search terms used were ginkgo*, tanakan, EGB-761, EGB761 and "EGB 761."
Selection Criteria
All relevant, unconfounded, randomized, double-blind controlled studies, in which extracts of Ginkgo biloba at any strength and over any period were compared with placebo for their effects on people with acquired cognitive impairment, including dementia, of any degree of severity.
Data collection and analysis
Data for the meta-analyses are based on reported summary statistics for each study. For the intention-to-treat analyses, we sought data for each outcome measure on every patient randomized, irrespective of compliance. For the analyses of completers we sought data on every patient who completed the study on treatment.
For continuous or ordinal variables, such as psychometric...