Do Statins Decrease Or Increase The Risk Of Parkinson’s Disease?

The Fine Print Behind The Misleading Headline

 Author: Dr. Stephen Chaney

 Human NeuronsI hadn’t paid much attention to the headlines saying “Statin Use May Decrease Parkinson’s Risk” until the other day when I happened to glance a couple of lines below the headline and spotted a statement saying “Study Shows That Discontinuation of Statin Therapy Increases Risk of Parkinson’s”.

 I immediately said to myself “That’s bizarre. There is a total disconnect between the headlines and the study.” If you really wanted to determine whether statin use reduced the risk of Parkinson’s, you would compare the incidence of Parkinson’s disease in a group of statin users and a matched group who did not use statins.

It turns out those studies have been done, and they were inconclusive – some studies showed a slight increase in Parkinson’s in statin users, some showed a slight decrease, and most showed no correlation between statin use and Parkinson’s.

In that context, this study could equally well have been interpreted as suggesting that statin use increased the risk of Parkinson’s, but somehow none of the headlines mentioned that possibility.

Are Both Possibilities Plausible?

 Let’s look at each possibility in detail. The reasoning is complex, but let me try to walk you through it.

 Could Statins Decrease The Risk Of Parkinson’s

 Parkinson’s is caused by the progressive degeneration of the brain neurons that produce a chemical messenger called dopamine that controls muscle movement. However, the causes of nerve degeneration in Parkinson’s patients are largely unknown.

Genetics may play a small role. Environmental toxins may play a role. But most experts feel that Parkinson’s patients produce an excess of free radicals, and it is the oxidative damage caused by those free radicals that results in the loss of the ability of neurons to produce dopamine.

But even that is not the whole answer. The brain is normally able to use coenzyme Q10, which is very abundant in brain, and other antioxidants to destroy free radicals before they damage brain neurons. Somehow in Parkinson’s patients free radical production and antioxidant production have gotten out of balance.

Advocates of the theory that statins may decrease the risk of Parkinson’s, point out that statins decrease oxidative damage. So if a person was predisposed to developing Parkinson’s and oxidative damage is a major cause of Parkinson’s, it is theoretically possible that statins could slow the progression to Parkinson’s while they were taking the drug. Of course, once they stopped taking the drug the oxidative damage to dopamine-producing neurons would resume and Parkinson’s would eventually develop.

In this model- Let’s call it Model A:

1)     Oxidative damage of dopamine-producing neurons was caused by some unspecified external agent.

2)     Statins protected the neurons from oxidative damage while they were being used.

3)     Once the statin drugs were discontinued oxidative damage resumed and the risk of developing Parkinson’s increased.

This is the model favored by the authors and repeated in all of the headlines you saw.

Could Statins Increase The Risk Of Parkinson’s?

Statins also interfere with the synthesis of cholesterol and coenzyme Q10, and these are both absolutely essential for brain function. Let’s start with cholesterol:

  •  20% of the body’s membrane cholesterol is found in the myelin sheath that coats the brain’s neurons (You can think of the myelin sheath as analogous to the plastic coating that insulates an electrical wire).
  • Cholesterol can’t cross the blood-brain barrier, which means that the brain cannot utilize cholesterol from the bloodstream . It has to make its own cholesterol.

As for coenzyme Q10:

  • It is not only a powerful antioxidant. It is also absolutely essential for cellular energy production.
  • The brain has tremendous energy requirements. The brain accounts for 20% of the energy utilization of our body. Neurons burn 2 times more energy than other cells in our body.

For both of these reasons, many experts have cautioned that statin drugs have the potential to cause neurodegenerative diseases such as Parkinson’s.  In this model – Lets call it model B:

1)     The statin drugs themselves are damaging the dopamine-producing neurons by inhibiting cholesterol and coenzyme Q10 synthesis in the brain.

2)     The antioxidant effects of the statin drugs were masking the damage caused by the statins while the drugs were being used.

3)     Once the statin drugs were discontinued the underlying damage was unmasked and the patients quickly developed Parkinson’s.

What Did The Study Actually Show?

The study (Lee et al, Neurology, 81: 410-416, 2013) looked at 43,810 statin users on the island of Taiwan. The Taiwanese Health System keeps extensive records of prescription use and health conditions of everyone on the island. It also requires that statin use be discontinued as soon as the patient reach their target of < 100 mg/dL LDL cholesterol, so they had the perfect population base to study what happens when you discontinue statin therapy.

The results were:

  • The patients who discontinued statin therapy were 42% less likely to develop Parkinson’s that those who continued on statin therapy. That result is consistent with both models A & B.
  • The increased risk of developing Parkinson’s when the drug was discontinued was only seen for the statin drugs like simvastatin and atorvastatin that are able to cross the blood brain barrier. That result is actually a bit more consistent with model B (Remember that the brain has to be able to make its own cholesterol and statins block cholesterol production).
  • When the study compared people using statin drugs to those not using statin drugs there was no significant difference in the prevalence of Parkinson’s – even for those statin drugs that cross the blood brain barrier. That means that merely being on a statin drug did not influence the risk of developing Parkinson’s. It was only when patients were on statin drugs for a period of time and were subsequently taken off statins that the risk of developing Parkinson’s was affected – and the effect was to increase risk! In the context of the first two findings, that result is also a bit more consistent with model B.

The Bottom Line:

If I were writing one of those medical blogs, I would have probably have gone with the party line and told you that statins decrease your risk of developing Parkinson’s. And if I were one of those health bloggers who never let the facts get in the way of a good story, I’d probably be scaring you with headlines saying that statins increase your risk of Parkinson’s.

But, I’m a scientist. I actually read the article, and I tell it to you like it is. Here’s your bottom line.

1)     Ignore the headlines. The study they are talking about can’t distinguish between statins increasing or decreasing the risk of Parkinson’s. Don’t let anyone tell you that reducing the risk of Parkinson’s is a side benefit of statin therapy. That simply has not been proven.

2)     The study does clearly show that discontinuing the statin drugs simvastatin and atorvastatin is associated with increased risk of developing Parkinson’s. That’s a big red flag for me, because 53% of patients discontinue statin therapy because of side effects, cost or other reasons.

3)     However, statin drugs do save lives, especially for people who have already had a heart attack, so talk with your doctor about the benefits and risks of statin drugs, and which statin drugs are best for you.

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure or prevent any disease.

How Much Exercise Do You Need?

“Exercise” Versus “Lifestyle Activity”: 

How Active Are You—Really?

Author: Dr. Pierre DuBois

canotThe most frequent questions I get are: “How much exercise do I need?” and “What’s the best way of getting that exercise?” If you are like most people, working out just for the sake of working out does not really appeal (although there are many dedicated gym buffs who couldn’t live without their daily workouts!).

We all know that it’s important to exercise regularly if we want to live a long and healthy life. However, if you find the idea of trotting along on a treadmill for 15 minutes and then spending half an hour of working out on Nautilus machines to be about as exciting as a trip to the dentist, then this article is for you!

What the Experts Recommend:

Experts recommend that we get at least 150 minutes of exercise each week to stay in shape. But many people find taking this much exercise at once (or in three 50-minute stretches) too daunting.

The good news is that a recent study conducted by researchers at Boston University that was published in the journal Medicine & Science in Sports & Exercise found that bouts of exercise lasting less than 10 minutes a couple of times daily, such as the kind you get when cleaning the house, were sufficient to meet your weekly exercise needs.

What the Study Showed

Over 2,000 participants were included in the study, more than half of whom were overweight. Motion detectors were attached to each of the subjects for eight days, and an average of half the participants met their weekly exercise quota of 150 minutes. The average participant met his or her quota with exercise that lasted less than 10 minutes at a time. The types of exercise ranged from moderate (heavy cleaning, walking briskly and sports such as golf and badminton) to vigorous (running, hiking, shoveling and farm work).

As long as the participants met their 150-minute per week quota, no matter the length of their exercise, they had lower body mass index, smaller waists, lower triglycerides and better cholesterol levels than those who did not meet the quota.

Assistant professor at Boston University’s School of Medicine, Nicole Glazer, says “This study really speaks to the idea that some activity is better than nothing. Parking a little bit farther away, getting off the bus one stop early—all of these little things can add up and are related to a healthier profile.”

For years, researchers have studied the effects of exercise from practicing sports or visiting the gym. However, according to Glazer, “This idea of lifestyle activity is one that is under-measured in research studies.” Activities such as taking the stairs instead of the elevator, using a push mower instead of a riding mower, etc. can add up to a significant amount of energy expenditure. Experts still stress that it’s important to also get in some traditional forms of exercise and not merely replace it with lifestyle activity. Still, any exercise is useful.

“The levels of sedentary behavior in this country are alarming. So the concern that someone’s going to stop exercising and instead just get off the bus a stop earlier, that’s not my concern,” Glazer says. “The real concern is, is this a stepping-stone? Is this the way we can get inactive people to do any sort of activity? People will come up with any excuse to not exercise. I don’t need to worry about my giving them one. They’ll be able to think of something.”

The Bottom Line:

  • Experts recommend 150 minutes of moderate intensity exercise a week
  • That doesn’t mean that you need to be a gym rat or marathoner. Ten minute exercise intervals centered around everyday lifestyle activities can be sufficient.
  • So you are out of excuses. You have the time. You have all the equipment you need. You don’t even need special workout clothes.

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure or prevent any disease.