Behavior symptoms may return if people with Alzheimer's disease stop taking a medicine that has helped them, a new study suggests. Some people with Alzheimer's disease have symptoms of psychosis. For example, they may hear or see things that aren't there or have false beliefs (delusions). Some may become anxious, angry or violent. Some people get symptom relief from risperidone (Risperdal) or other anti-psychotic drugs. But other research has found that Alzheimer's patients taking such drugs may die sooner. U.S. drug guidelines recommend careful monitoring of these patients. The new study included 110 people with Alzheimer's. All of them had taken risperidone for 4 months and had responded well. They were randomly divided into 3 groups. One group kept taking the drug for 8 months. One continued for 4 months, then switched to placebo (fake) pills. One switched to placebo for 4 months. Symptoms came back in 60% of those who switched right away and 48% of those who switched after 4 months. About 15% of those who stayed on the drug had a relapse. The New England Journal of Medicine published the study. HealthDay News and WebMD wrote about it October 17.

By Robert H. Shmerling, M.D.
Harvard Medical School

What Is the Doctor's Reaction?

Sometimes the only way to know if a medicine is working is to stop it.

Of course, this should only be done with a doctor's approval. But the issue comes up often with my patients who have arthritis. When rheumatoid arthritis first develops, the aim is to suppress inflammation quickly. Treatment is usually quite effective. But it can be hard to know whether the medicines are still needed months or even years later.

When a patient asks me "Do I still need this medicine?" I often recommend a bit of an experiment. We will gradually reduce and eventually stop one or more of the treatments. In this way, we can figure out how much or how little medicine is still necessary.

A new study performed a similar experiment. Researchers looked at the effect of continuing or stopping a drug called risperidone for people with Alzheimer's disease. This medicine can be quite effective for some Alzheimer's patients. It is used to treat symptoms of psychosis (including hallucinations or delusions or both), agitation or aggression.

These are important symptoms to treat effectively. They can be quite unpleasant for the patient. And they can make it hard for family, friends and health care workers to provide care.

The study included 180 people with Alzheimer's disease. They had been taking risperidone for psychosis, agitation or aggression. About 60% of these patients had improved on the drug. After 4 months of treatment, people who had improved were divided into 3 treatment groups:

• Continue risperidone for 8 months.
• Continue risperidone for 4 months, then switch to placebo pills that look the same for 4 months.
• Stop treatment and switch to placebo for 8 months.

People who quit the drugs were more likely to get worse. Symptoms came back for:

• 60% of those switched to placebo right away
• 48% of those switched to placebo after 4 months
• 15% of those who continued taking risperidone

Most side effects were minor and similar between those receiving risperidone and placebo.

This study provides some important information for Alzheimer's disease patients, their loved ones and their caregivers. If risperidone helps to control symptoms, it's probably better to continue it. However, this study did not try to find out the ideal length of treatment.

It's also worth noting that the Food and Drug Administration has not approved risperidone to treat people who are elderly and demented with behavior symptoms such as those in this study. In fact, antipsychotic drugs (including risperidone) come with a warning that their use for dementia-related psychosis is linked with an increased risk of death. However, they are sometimes used for this purpose, especially when other options don't work. Regular monitoring is essential.

The study was small, so it needs to be confirmed by others. But it should help to reassure caregivers who wonder if it's important for their patient to continue risperidone.

What Changes Can I Make Now?

There is no specific treatment proven to prevent Alzheimer's disease. However, changes in lifestyle may reduce the risk of developing this or other brain diseases. For example, high blood pressure (hypertension) increases the risk of stroke. Getting high blood pressure treated can lower stroke risk.

You also can make other changes to help keep your brain healthy.

• Increase exercise. The risk of Alzheimer's disease seems to be lower among people who are physically active.
• Improve your diet. Include more fruits, vegetables and omega-3 fatty acids. Eat less salt and saturated and trans fats.
• Keep your cholesterol in a good range. If your total or LDL ("bad cholesterol") is high or if your HDL ("good cholesterol") is low, talk to your doctor about how to improve them.
• Keep your weight in a healthy range. If your body mass index (BMI) is over 25 (and especially if it's over 30), try to lose excess weight by cutting calories and exercising more. People who are obese are more likely to develop dementia. Obesity also increases the risk of diabetes, high blood pressure and abnormal cholesterol. All of these factors increase the risk of stroke. Talk to your doctor about weight loss programs, especially if you are unable to lose weight on your own.
• Don't smoke. If you're a smoker, commit to quitting. Your doctor can recommend medicines and programs to help you quit.
• Keep your mind active. The overall benefit is uncertain, but some studies suggest that dementia is less common among those with hobbies and a busy social life. Activities that challenge your brain (such as board games) may also help.

If you already have Alzheimer's disease, several medicines may slow the progression of disease or treat symptoms.

Finally, review your medicines regularly with your doctor and pharmacist. It's worth asking whether all of them are necessary. You may find that some can be taken "as needed" rather than every day. Others may be less important now than when you started them. Reviewing your medicines regularly also helps to make sure there are no dangerous interactions between drugs.

What Can I Expect Looking to the Future?

As the U.S. population ages, you can expect to hear much more about rising rates of Alzheimer's disease. You'll also hear about the terrible toll it takes on patients and their families. I hope that researchers will soon discover the cause of Alzheimer's disease. This should lead to better ways to prevent and treat it.