psoriasis lesions on a hand

More than skin deep: NHLBI studies explore links between psoriasis and heart disease

Pair of studies show harmful changes to arteries, point way to possible treatment

For years, researchers have been studying the surprising link between psoriasis—an inflammatory skin disease—and an increased risk for heart disease. Now, a pair of recent studies funded by the National Heart, Lung, and Blood Institute (NHLBI) offer new insights into this connection and provide exciting evidence that aggressive treatment of psoriasis may keep heart disease at bay.  

Psoriasis, which is characterized by itchy patches of thick, scaly skin mostly on the elbows and knees, affects an estimated 7 million Americans, and another 3 million yet to be diagnosed. The medical community increasingly is recognizing the condition as a serious, chronic illness and acknowledges that in severe cases, it is difficult to treat. 
Yet researchers are making progress. In recent years, a growing body of evidence has shown psoriasis to be a risk factor for atherosclerosis, or hardening of the arteries, which is the major cause of heart attacks. For reasons still poorly understood, people with psoriasis experience heart attacks at a younger age than those without the condition. Other studies have shown a link between psoriasis and inflammation in the large blood vessels of the body.  

The new NHLBI-funded studies build on both these findings. They show that treatment of the skin disease improves both vascular (blood vessel) inflammation and coronary artery disease. 

“Psoriasis is more than skin deep—the data linking it to heart disease is strong,” said Nehal N. Mehta, M.D., a preventive cardiologist and chief of the Section of Inflammation and Cardiometabolic Diseases at NHLBI. “The good news,” added Mehta, the lead author of both journal studies, “is that there’s growing evidence that treating the skin condition may also help lower cardiovascular risk factors and early vascular diseases in these patients.”  

Coronary artery of psoriasis patient before and after treatment
Credit: Credit: Marcus Chen, MD and Nehal N. Mehta MD, NHLBI.

High-resolution imaging reveals reduction in plaque in the left coronary artery of heart after treatment of psoriasis for 1 year. Credit: Marcus Chen, MD and Nehal N. Mehta MD, NHLBI.

To find out whether treating psoriasis could lead to reduced vascular inflammation, Mehta and his colleagues conducted a study, later published in JAMA Cardiology, that used a combination of anti-inflammatory approaches, including medications and light therapy, on a group of 115 patients. After one year of treatment, most of the patients experienced a 33 percent reduction in skin inflammation severity and a six percent reduction in inflammation of their coronary arteries. Some patients even achieved a 75 percent reduction in skin inflammation and an 11 percent reduction in artery inflammation.  

“All types of treatments for psoriasis were included, which suggests that treating the disease itself may impart benefit beyond the skin,” Mehta said. 

In the second journal study, published in Circulation, Mehta and his team examined whether psoriasis directly affected the coronary arteries. The scientists found evidence that psoriasis patients have higher levels of a dangerous type of coronary-artery plaque associated with heart attacks when compared to a group of patients without psoriasis of a similar age and gender.  These higher plaque levels showed up in the psoriasis patients, regardless of the severity of their condition, the researchers said. 
Strikingly, when compared to non-psoriasis patients who were 10 years older and had high blood cholesterol, the patients with psoriasis still showed higher levels of this plaque, which can rupture and increase the likelihood of a heart attack.  

As in the other study, Mehta found that patients who experienced a reduction in the severity of their psoriasis, also experienced a reduction in coronary plaque.  

“These findings suggest that treating the skin of psoriasis patients may improve the health of the underlying blood vessels and thereby reduce the risk of heart disease,” Mehta said. “Importantly, patients with psoriasis should be aggressively screened for cardiovascular risk factors and should be educated about their elevated cardiovascular risk.”  
Mehta emphasized that clinical trials are needed to confirm these early observational findings. He pointed out that association does not prove causation: The underlying biological mechanisms linking a reduction in skin inflammation to a reduction in coronary artery plaque are unclear, he noted. Future studies should attempt to characterize these mechanisms in the ongoing effort to reduce the burden of cardiovascular disease, he said.