Background: Nicotine is a cholinergic agonist that also has a presynaptic effect in releasing acetylcholine. In animal model has been shown to reverse spatial memory deficits produced by lesions in the medial septal nucleus of rats, and in aged monkeys nicotine administration improves memory and alertness to visual stimuli. Observational studies have claimed a protective effect of smoking against Alzheimer's disease (AD), but recent studies have called this into question. Smoking is a risk factor for stroke and so, possibly, for vascular dementia. Because nicotine has adverse effects, it is important to conduct a systematic review to assess the clinical efficacy and safety of nicotine for patients with AD OBJECTIVES: To evaluate the efficacy and safety of nicotine, administered in any way or form, for people with Alzheimer's disease.
Search strategy: The trials were identified from a search of the Specialized Register of the Cochrane Dementia and Cognitive Improvement Group on 24 January 2001 using the term nicotine.
Selection criteria: All unconfounded, double-blind, randomized trials in which treatment with nicotine patches or administration of nicotine intravenously or in any other way or form was administered for more than a day and compared with placebo for people with Alzheimer's disease.
Data collection and analysis: The one included trial did not present results suitable for inclusion in the review.
Main results: The poor quality of trials did not allow any synthesis of data across studies.
Reviewer's conclusions: This review is not able to provide any evidence that nicotine is a useful treatment for Alzheimer's disease.