Past studies have shown that people with psoriasis—a chronic skin disease—have a higher risk for heart attack and stroke. And that seemed curious. But now researchers have figured out a potential connection, and the answer could help people with psoriasis live healthier, “longer lives.

For more information, I called lead researcher Nehal N. Mehta, MD, director of the inflammatory risk clinic in the preventive cardiology program at University of Pennsylvania’s Perelman School of Medicine in Philadelphia. He and his colleagues reported their findings at the November 15, 2011 annual meeting of the American Heart Association in Orlando, Florida.

THE CHOLESTEROL CONNECTION

It turns out that abnormal cholesterol levels, composition and function may be what links psoriasis, heart attack and stroke. But before we see why, it’s important to review some basics about how cholesterol works. There are three major components of your total cholesterol level: LDL cholesterol, HDL cholesterol and triglycerides (blood fats). You need all three of these components to be at appropriate levels for good health. But high LDL cholesterol can cause heart disease, and people with high triglycerides tend to have high LDL, so they are both referred to as “bad”—while HDL cholesterol helps clear the arteries of LDL cholesterol, so it is referred to as “good.”

So why does this matter? Well, Dr. Mehta told me that previous research has suggested, anecdotally, that HDL “good” cholesterol, specifically, may be lower in people who have psoriasis. He and his colleagues wanted to confirm this scientifically—but they also wanted to dig deeper into the topic. They wanted to see whether cholesterol composition was different among those with psoriasis. And they also wanted to see if HDL cholesterol actually functions differently in people with psoriasis.

In studying 78 adults with psoriasis and a control group of 84 people without the disease, Dr. Mehta and his team found that…

  • People with psoriasis did, in fact, have lower HDL levels. Their LDL levels and even their total cholesterol levels were actually considered lower and healthier than the control group’s, and the triglyceride levels in both groups were in healthy ranges. But, as suspected, their HDL measure, in particular, fell into an unhealthy range. They scored a 47, which was significantly lower than the control group’s 55.

  • Cholesterol composition was different among those with psoriasis. The particles were smaller and denser among people with the skin disease, compared with the control group, which puts them at increased risk for cardiovascular problems.

  • HDL function was significantly lower in people with psoriasis. In people with psoriasis, HDL was 25% less effective in removing LDL cholesterol from artery walls compared with HDL in the control group.

What’s intriguing about this finding if you have psoriasis is that it shows that knowing your total cholesterol level and even the breakdown of your HDL, LDL and triglycerides doesn’t come close to giving you the full picture of your heart health. The way your cholesterol is composed and works within your body can also be a factor—possibly even more important than simply knowing your HDL level—when it comes to your cardiovascular risk. But the tests for composition and function are newer—the latter, for example, is used only in research labs and is difficult to perform—so unfortunately it’s not possible to ask your doctor for all of these measurements.

So why would psoriasis affect the level, composition and function of HDL cholesterol? Dr. Mehta suspects that the inflammation generated by psoriasis—specifically, inflammation in the liver—may negatively affect all of those things. He added that further studies are needed to validate these findings and confirm cause and effect.

USE THIS FOR YOUR OWN HEART

Dr. Mehta isn’t sure whether treating psoriasis would help improve the level, composition and function of HDL—more research needs to be done to answer that question, he said. But he did tell me that past studies have shown that consuming omega-3 fatty acids (from fish and/or supplements, for example), losing weight and exercising more all can improve your level of HDL, its composition and its function. Good advice for everyone… and even more crucial for those with psoriasis.