People with psoriatic arthritis (PsA) are at increased risk of cardiovascular disease (CVD) compared with people who don’t have PsA, according to a meta-analysis published in the April issue of Arthritis Care and Research. Lead investigator Lihi Eder, MD, PhD, says the study is among the first to quantify the relationship between heart disease and psoriatic arthritis – a form of inflammatory arthritis that usually develops in people who have the skin disease psoriasis.
“There were many studies of other chronic inflammatory conditions, such as psoriasis and rheumatoid arthritis (RA), but it was unclear whether patients with PsA are at increased risk of developing cardiovascular diseases. Furthermore, the extent of this risk was unknown. Studies from different parts of the world that were published in the last two or three years allowed us to perform this meta-analysis and quantify the risk,” Dr. Eder explains.
For their review, Dr. Eder and colleagues at the University of Toronto in Canada obtained information from three large medical databases and from recent presentations at rheumatology conferences. They eventually focused on 11 high quality studies, mostly from North America and Europe, involving nearly 33,000 patients with psoriatic arthritis.
To be included, the studies had to take into account the ordinary risk factors for CVD, including age, sex and health conditions such as high blood pressure and diabetes. The selected studies also had to include a control group of people who did not have psoriasis or a rheumatic disease.
All the studies showed a significantly increased risk of cardiovascular disease in people with PsA, although the level of risk varied slightly, depending on the study type. Overall, people with psoriatic arthritis were 43% more likely to have or to develop heart disease compared to the general population. They also had a 31% increased risk of heart failure and a 22% increased risk of cerebrovascular disease – conditions, such as stroke, that affect blood flow to the brain. The degree of risk is similar to that found in people who have severe psoriasis without PsA.
Psoriasis, in fact, has long been associated with an increased risk of heart attack and stroke, but the reason wasn’t clear. It’s now known that the inflammatory processes in cardiovascular disease and conditions such as PsA, psoriasis and rheumatoid arthritis have much in common.
Atherosclerosis is the fatty buildup on blood vessel walls that can lead to cardiovascular disease (including heart attack, stroke and coronary artery disease). It results from chronic low-grade inflammation in the innermost layer of blood vessels. Studies have shown that people with psoriatic arthritis have higher rates of atherosclerosis than the general population and that those who develop it have more inflammation overall. Thus, Dr. Eder says, PsA should be considered a risk factor for heart disease.
Learning the factors that contribute to heart disease is important. For one thing, it will help doctors identify and treat high-risk patients early, before they develop symptoms.
Current cardiovascular risk assessments, which use medical history and lifestyle information to predict a person’s chance of having a heart attack, were developed for the general population, so they underestimate the risk in people with PsA.
Dr. Eder says more research is needed to find the best way to help doctors identify patients with psoriatic arthritis who are at high risk of cardiovascular disease.
In the meantime, she says all patients with PsA should be screened for factors that put them at risk of heart disease, such as diabetes and high cholesterol, and that these should be aggressively treated.
“There is need to increase the awareness of primary care physicians and specialists to the high cardiovascular risk associated with psoriatic disease. Studies have shown that a significant proportion of patients with psoriatic disease are underdiagnosed and undertreated for traditional cardiovascular risk factors,” she says. “I hope the results of this study will increase this awareness.”
New PsA treatment guidelines from The Group for Research and Assessment of Psoriasis and Psoriatic Arthritis (GRAPPA) released this year stress the importance of screening for cardiovascular disease and other common comorbidities.
Petros Efthimiou, MD, associate chief of rheumatology at New York Methodist Hospital and an associate professor at Weill Cornell Medical College, says the meta-analysis is useful because some of the original studies had conflicting results.
“While skin psoriasis, especially severe psoriasis, has been well established through independent meta-analyses as a cardiovascular risk factor, this study represents the first systematic analysis of the literature for psoriatic arthritis,” he says. “The findings confirm that, indeed, patients with PsA have a higher risk of developing [heart attack], heart failure and stroke. Furthermore, the formulas that have been developed for the general population and used until now to measure cardiovascular risk in PsA patients may have underestimated the true risk.”
But Dr. Efthimiou, who was not involved in the study, also points out that it was “not possible to ascertain whether PsA disease activity influences the magnitude of the additional risk.” This is important because if higher disease activity means greater risk, targeting the underlying inflammatory process in PsA may decrease the risk.
In the meantime, he says “primary care physicians and cardiologists should treat PsA patients as higher risk patients, similar to those with psoriasis, rheumatoid arthritis, lupus and diabetes mellitus, and modify traditional risk factors [such as] high cholesterol, smoking and high blood pressure.”
Author: Linda Rath for the Arthritis Foundation