In addition to the various drugs approved for use in treating Alzheimer’s disease, there is considerable interest in the use of other treatment therapies.
This page provides a brief summary of information about some of these.
Because of the possibility of side effects and drug interactions, people are strongly advised to consult with their doctor if considering using any of these therapies.
Finding evidence for the treatment of dementia
To date, much of the information we have about the treatment of dementia comes from epidemiological studies where individuals who have taken the therapy are compared with a control group of individuals who have not taken the therapy.
Other information comes from research using different methods. These include:
- Open label studies which have not had a control group or controlled trials which have not been large enough to definitely show an effect.
- Double blind studies in which neither the participant or the doctor is aware of which therapy is allocated to which person.
- Randomised controlled trials in which participants are allocated by random numbers either to a group receiving treatment or to a group with no active treatment.
Large prospective double blind randomised placebo controlled trials need to be undertaken to confirm the value of taking a drug or supplement for the treatment of dementia.
In the case of most of the therapies outlined in this Update Sheet, such trials are currently underway or have not yet been done.
Prospects for the treatment of Alzheimer’s disease and Vascular dementia
Oestrogen appears to have a number of beneficial effects on the brain and it is possible that it may protect the brain from deterioration in several ways.
It has been suggested that oestrogen replacement therapy for postmenopausal women might delay the onset of Alzheimer’s disease or prevent postmenopausal women from ultimately developing Alzheimer’s disease.
Data from several case control studies have found that oestrogen replacement may be associated with a 30% lower risk of developing Alzheimer’s disease. However, some of these studies are flawed because the individuals taking oestrogen have differed on basic variables such as education and social class from individuals not taking oestrogen.
No randomised controlled study has shown that oestrogen prevents Alzheimer’s disease or diminishes one’s chance of getting it. In the Women’s Health Initiative Memory Study, oestrogen (alone or with progestin) actually increased the chance of developing Alzheimer’s disease.
Two recent trials using oestrogen to treat Alzheimer’s disease have found absolutely no benefit for women who already have Alzheimer’s disease. In addition, some forms of hormone replacement therapy have been associated with an increased risk of dementia and may, by implication, worsen dementia already present.
Oestrogen has significant effects, both good and bad, if taken after the menopause.
Specialists treating patients with Alzheimer’s disease in Australia do NOT recommend the use of oestrogen as treatment for women at risk of Alzheimer’s disease or in women who have Alzheimer’s disease, although it is not contra-indicated in Alzheimer’s disease if used for another purpose such as treating post-menopausal symptoms.
Anti-inflammatory agents counteract or suppress the inflammatory process. They include non steroidal anti-inflammatory drugs (NSAIDs), which, as well as having pain-relieving effects, have the effect of reducing inflammation when used over a period of time. COX 2 inhibitors are the newest generation of NSAIDs, which are generally as effective as traditional NSAIDs, but with less risk of side effects.
All trials to date have indicated however that anti-inflammatory drugs have no useful effect in treating established Alzheimer’s disease.
Some case control studies have suggested that people taking anti-inflammatory drugs might be at lower risk of developing Alzheimer’s disease than people not taking such drugs, but these results have not been confirmed in prospective randomised placebo control trials of people at risk of Alzheimer’s disease. A drug trial in a large population without dementia, the ADAPT trial, was terminated due to concerns about the side effects of one of the anti-inflammatory agents.
Anti-inflammatory drugs have a wide range of potentially serious side effects and their use for treatment or prevention of Alzheimer’s disease is inappropriate at the present time.
Folate and Vitamin B12
Folate (folic acid) is a naturally occurring nutrient and is essential for the health of blood cells and nerve cells. It is found in green vegetables such as spinach and broccoli.
High levels of folic acid in the blood decrease the level of another sub-stance called homocysteine which is normally present in blood. High levels of homocysteine in the blood are associated with an increased risk of coronary artery disease and stroke.
At least two studies have suggested that high levels of homocysteine and/or low levels of folic acid may be associated with a higher rate of developing Alzheimer’s disease later on. One trial of folate supplementation in those with normal cognition showed a reduced risk of cognitive decline, but at this stage there is no evidence that folate prevents Alzheimer’s disease. Folic acid is safe and cheap, but anybody considering the use of folic acid for the prevention or treatment of Alzheimer’s disease should discuss this with their doctor.
Vitamin B12 deficiency, which also increases homocysteine levels, has also been associated with an increased risk of Alzheimer's disease. Again, prospective treatment trials are needed to show the benefits of B12 supplements.
Vitamin E is a naturally occurring fat soluble vitamin. Vitamin E may protect the body’s cells against the effects of ageing. One American study suggested that taking Vitamin E decreased the rate at which people with more severe Alzheimer’s disease deteriorated.
Currently the American Association of Neurology has a guideline suggesting that the use of Vitamin E should be considered for patients with established Alzheimer’s disease.
In Australia specialists treating Alzheimer’s disease vary in their assessment of the possible benefits of Vitamin E. Vitamin E can prolong bleeding time and make haemorrhage more likely. A recent analysis of several trials showed that daily doses of Vitamin E above 400mg increased mortality and other events such as stroke.
Anyone contemplating taking Vitamin E for the treatment or prevention of Alzheimer’s disease should discuss this with their doctor. No studies demonstrating that Vitamin E can prevent Alzheimer’s disease have been published, but more prospective randomised controlled trials are needed.
These cholesterol-lowering drugs have been associated with a lower risk of developing dementia, but to date no study has shown that these agents are effective in the treatment of dementia. One large trial is in progress using a statin and Aricept.
Ginkgo biloba, derived from the leaves of a Chinese tree, is said to have anti-inflammatory, anti-oxidant and anti-platelet properties. It is one of the more commonly used complementary medicines for cognitive problems and is licensed for the treatment of Alzheimer’s disease in Germany. To date, it is only the extract EGb 761 that has been suggested to be of possible benefit and such benefits are only mild (about half that of cholinergic therapies). It does not preserve memory in those with normal cognition.
Further research is needed before a definitive statement can be made about its effectiveness as a treatment.
This preparation is marketed as a herbal “memory booster”. There are however no clinical data to suggest that it is beneficial to people with dementia.
A large range of other agents have been trialed in the treatment, and often prevention, of dementia, but none have yet been shown to be effective. This includes curcumin (in curry powder), agents to treat diabetes, blood pressure lowering drugs, aspirin and agents to improve blood flow.
Trials are in progress assessing benefits of an Alzheimer’s vaccine (having a component of the amyloid protein found in plaques), inhibitors of the enzymes that produce amyloid and therapies using nerve growth factor. These approaches may prove to be effective, but much more work is needed.
What kinds of questions should you ask your doctor about any treatments being considered?
- What drugs (prescription and over-the-counter) might interact with the treatment?
- How might this treatment affect other medical conditions?
- What are the potential benefits of using this treatment?
- How long before improvement may be noticed?
- What are the known side effects?
- If there are side effects, should the treatment be reduced or stopped?
- If the treatment is stopped suddenly, what happens?
- Are there any changes that should be reported immediately?
- How often will a visit to the doctor who prescribed the treatment be needed?
This publication provides a general summary only of the subject matter covered. People should seek professional advice about the specific case. Alzheimer's Australia is not liable for any error or omission in this publication, even if negligent.