Stopping your cholesterol-lowering drugs may increase your risk of Parkinson's disease, a new study suggests. The study involved 43,810 people in Taiwan who were taking statins and did not have Parkinson's disease when the study began. Researchers used pharmacy records to verify statin use. People who stopped taking certain statins had a 58% higher risk of Parkinson's disease than those who continued taking their statin medicine. Only statins such as simvastatin and atorvastatin were associated with a reduced risk of Parkinson's disease. These are "fat soluble." They tend to deposit in fat-containing tissues and are thought to get into brain tissue more easily than other statins. People who took water-soluble statins, such as pravastatin and rosuvastatin, did not have a lower risk of Parkinson's disease compared to those who stopped the drug. The article appeared in the July 24 online issue of Neurology.
By Robert H. Shmerling, M.D.
Harvard Medical School
What Is the Doctor's Reaction?
Did you ever wonder if your medication is working? It can be hard to know.
For example, I see many patients who take medicines for arthritis and aren't sure if they are helping much. I’ll often suggest they reduce or even stop the medicine. That may be the only way to find out if the medicine is working. In some cases, we learn that with or without the medicine, symptoms are about the same. For others, they only realize how well the medicine was working when their joint pain increased dramatically once the medicine was stopped.
A similar principle is behind a study just published in the latest issue of the medical journal, Neurology.
Previous research has hinted at the possibility that cholesterol-lowering statin medicine might reduce the risk of Parkinson’s disease, a degenerative brain disease that causes tremors, muscle rigidity or problems with movement.
Proving that statin treatment can reduce the risk of Parkinson's disease could provide hope for millions of people at risk for this debilitating disease. Those at high risk might take the medicine to prevent its development. And proving that statins lower the risk of Parkinson's disease could provide a better understanding about why the illness develops in the first place.
This new study took advantage of a national health insurance policy in Taiwan that encourages doctors to stop statin medicines once the cholesterol is sufficiently reduced. (In the United States, statin drugs are usually continued even after the cholesterol falls).
Among nearly 44,000 people taking statins and who were free of Parkinson's disease at the start of the study:
- Those who stopped taking certain statins had a 58% higher risk of Parkinson's disease than those who continued taking their statin medicine. The statins linked to a lower risk of Parkinson's disease, such as simvastatin and atorvastatin, are "fat soluble." That means they tend to deposit in fat-containing tissues and are thought to get into brain tissue more easily than other statins.
- Those who continued taking other statins ("water soluble" statins, such as pravastatin and rosuvastatin) did not have a lower risk of Parkinson's disease compared to those who stopped the drug.
- The actual rate of Parkinson's disease was about 1.7 cases per one million person-days on the fat-soluble statins and about 3.52 cases per one million person-days on other statins. (Person-days are simply units that multiply the number of people studied by the amount of time; so, 1,000 people taking statins for 20 years would equal 20,000 person-years of observation).
Why should statins reduce the risk of Parkinson's disease? No one knows for sure, but one possibility is that it reduces inflammation in the brain. Another is that the rising cholesterol that may accompany stopping a statin may harm the brain and trigger Parkinson's disease.
These findings are exciting and could lead to important advances in our understanding and treatment of Parkinson's disease. However, this study does not prove that statins can prevent Parkinson's disease or treat it once it develops.
What Changes Can I Make Now?
Currently, there is no reliable way to prevent Parkinson's disease. However, if you have a family history of Parkinson's disease – especially if someone in your family developed the disease before age 60 - talk to your doctor about this study and whether you should take a statin.
The biggest impact of this latest study may be for people with a family history of Parkinson's disease and borderline high cholesterol. For such individuals, the potential reduction in the risk of Parkinson's disease might be enough for your doctor to recommend statin treatment.
If you already have Parkinson's disease, talk with your doctors about your treatment options. For mild symptoms, no treatment may be necessary. For more severe symptoms, there are several medicines that can reduce symptoms and improve quality of life.
If standard medicines aren't effective, your doctor may recommend a "brain pacemaker," in which a small electric current is applied to tiny wires inserted into precise locations of the brain. Other treatments may be available in clinical trials of Parkinson's disease.
It's important to have regular follow-up to monitor treatment and to consider other options if current treatments is not working well or if you are experiencing significant side effects.
Remain as active as you can. Many people with Parkinson's disease maintain or even improve mobility and function by regular exercise, sometimes with the help of a physical therapist. Falling is a particularly common and serious problem for those with Parkinson's disease. Exercises to improve balance and aids (such as a cane or a walker) can help.
You can learn more about the condition by contacting the National Parkinson Foundation, The American Parkinson Disease Association or the Parkinson's Disease Foundation.
What Can I Expect Looking to the Future?
You can expect researchers to continue to identify innovative treatments for Parkinson's disease. However, as good as new treatments may be, prevention would be even better. In the future, statin treatment could become a common preventive therapy for this condition.
In addition, it is likely that researchers will identify genes that are connected to Parkinson's disease. The challenge will be figuring out the specifics of that connection and how to use that knowledge to prevent or treat Parkinson's disease.
Send this page to a friend