Statins, or cholesterol-lowering drugs, are prescribed with for many individuals with elevated cholesterol levels. As is the case with any medication, untoward side-effects can occur. A new study found that some cholesterol-lowering medications posed a risk for Parkinson’s disease if a patient discontinued taking them. The results of the study were published in the July 24 online issue of Neurology, the medical journal of the American Academy of Neurology.
The authors note that previous studies on the relationship between statins and the risk of Parkinson’s disease have had inconsistent results. The current study comprised 43,810 people in Taiwan who were taking statins and did not have Parkinson’s disease. Taiwan’s compulsory national health insurance program reimbursement policy requests that doctors stop prescribing statins once the patient’s cholesterol reaches the treatment goal, which is contrary to standard treatment in the United States. “This policy allowed us to see whether there was any difference in the risk of Parkinson’s in people who stopped taking statins compared to the ones who kept taking them,” said study author Jou-Wei Lin, MD, PhD, of National Taiwan University in Taipei.
The researchers found that one type of statin was associated with Parkinson’s disease, while another was not. The use of lipophilic, or fat-soluble, statins such as simvastatin (Zocor) and atorvastatin (Lipitor) was associated with an increased risk of Parkinson’s disease, while no such association was found for hydrophilic, or water-soluble, statins such as pravastatin (Pravachol or Selektine) and rosuvastatin (Crestor).
The investigators found that the individual who stopped taking the fat-soluble statins were 58% more likely to develop Parkinson’s disease than those who kept taking the drugs: an absolute risk of 2.65 cases per one million person-days. This result was consistent even after adjusting for other conditions such as diabetes and high blood pressure.
The researchers also examined how many people taking the two types of statins developed Parkinson’s disease, compared to the number of person-days spent on the medication to come up with an incidence rate. A total of 25 people taking fat-soluble statins developed Parkinson’s from a total of nearly 15 million person-days on the drugs, for a rate of 1.68 cases per one million person-days on the drugs. For the water-soluble statins, 14 people developed Parkinson’s from nearly four million person-days on the drugs, for a rate of 3.52 cases per one million person-days on the drugs. Dr. Lin explained, “The fat-soluble statins are better able to cross the blood-brain barrier than the water-soluble statins.”
Take home message:
This study illustrates the point that all medications have both risks and benefits. Thus, one should consider the risks versus benefits and discuss them with a healthcare provider. A study released last April found an increased risk of diabetes among individuals taking statins. Also, a book released earlier this year discusses the pros and cons of statin therapy. “The Great Cholesterol Myth: Why Lowering Your Cholesterol Won’t Prevent Heart Disease-and the Statin-Free Plan That Will” by Nutritionist Jonny Bowden, PhD and cardiologist Stephen Sinatra, MD. The book notes that the only individuals that may benefit from statins are middle-aged men that have suffered a heart attack. In addition, statins do not reduce the risk of death for men of any age who have not suffered a heart attack, women, or children. It explains that statins increase the risk of diabetes, cancer, erectile dysfunction, mental confusion, and memory loss.