Items in AFP with MESH term: Vitamin E
New Drugs for Alzheimer's Disease - Article
ABSTRACT: Alzheimer's disease is characterized by degeneration of various structures in the brain, with development of amyloid plaques and neurofibrillary tangles. Deficiencies of acetylcholine and other neurotransmitters also occur. Pharmacologic treatment of the disease generally seeks to correct the histopathology, the biochemical derangements or their effects. The only drugs labeled to date for the treatment of cognitive symptoms in patients with Alzheimer's disease are two cholinesterase inhibitors that prevent the breakdown of acetylcholine in the synapse. Both medications are associated with modest improvements in cognitive function. However, all benefit is lost when these drugs are discontinued; the disease then progresses to the level seen in placebo-treated patients. Tacrine, the first cholinesterase inhibitor to be so labeled, must be taken four times daily and is associated with hepatic toxicity. Donepezil is taken once daily. Side effects of the cholinesterase inhibitors include nausea, vomiting and diarrhea, which tend to subside after the titration period. Other drugs that have shown some promise in the treatment of Alzheimer's disease are vitamin E, estrogen, selegiline and a mixture of ergoloid mesylates. Anti-inflammatory drugs and nicotine are also being studied for their effects as neuroprotectors or neurotransmitter enhancers. The caregivers of patients with Alzheimer's disease may see little effect from these or other investigational agents, but nursing home placement may be delayed.
ABSTRACT: Management of the most common type of dementia--Alzheimer's disease--is becoming increasingly sophisticated. Differentiation of Alzheimer's disease from vascular dementia has become therapeutically important, since the choice of treatments depends on the diagnosis. Two cholinesterase inhibitors, donepezil and tacrine, are labeled for use in patients with Alzheimer's disease. Other therapies, such as estrogen, nonsteroidal anti-inflammatory drugs and vitamin E, are sometimes used and show promise in delaying the progression of this dementia. Behavior problems, which often accompany the disease, can be managed using environmental modification, alterations in caregiving and medication. In the terminal phase of the illness, quality care involves implementing advance directives, communicating with the family, individualizing care and attending to patient comfort.
ABSTRACT: Clinical use of antioxidant vitamin supplementation may help to prevent coronary heart disease (CHD). Epidemiologic studies find lower CHD morbidity and mortality in persons who consume larger quantities of antioxidants in foods or supplements. Clinical trials indicate that supplementation with certain nutrients is beneficial in reducing the incidence of CHD events. Recent studies show that supplementation with antioxidant vitamins E and C have benefits in CHD prevention; however, supplementation with beta-carotene may have deleterious effects and is not recommended. Current evidence suggests that patients with CHD would probably benefit from taking vitamin E in a dosage of 400 IU per day and vitamin C in a dosage of 500 to 1,000 mg per day. Clinicians may also want to consider vitamin supplementation for CHD prevention in high-risk patients. Folate lowers elevated homocysteine levels, but evidence for routine supplemental use does not yet exist. Other nutritional supplements are currently under investigation.
ABSTRACT: Alzheimer's disease is characterized by the development of senile plaques and neurofibrillary tangles, which are associated with neuronal destruction, particularly in cholinergic neurons. Drugs that inhibit the degradation of acetylcholine within synapses are the mainstay of therapy. Donepezil, rivastigmine, and galantamine are safe but have potentially troublesome cholinergic side effects, including nausea, anorexia, diarrhea, vomiting, and weight loss. These adverse reactions are often self-limited and can be minimized by slow drug titration. Acetylcholinesterase inhibitors appear to be effective, but the magnitude of benefit may be greater in clinical trials than in practice. The drugs clearly improve cognition, but evidence is less robust for benefits in delaying nursing home placement and improving functional ability and behaviors. Benefit for vitamin E or selegiline has been suggested, but supporting evidence is not strong. Most guidelines for monitoring drug therapy in patients with Alzheimer's disease recommend periodic measurements of cognition and functional ability. The guidelines generally advise discontinuing therapy with acetylcholinesterase inhibitors when dementia becomes severe.