Psoriasis patients may have increased risk of myocardial infarction

Philadelphia - It is estimated that psoriasis affects 1.5 percent to 2.5 percent of the general population, with more than 4.5 million adults affected here in the United States alone. Approximately 20 percent of patients afflicted with this disease are categorized as "moderate-to-severe".

Aside from affecting the skin, joints and nails, recent evidence has linked psoriasis to myocardial infarction, explains Joel M. Gelfand, M.D., M.S.C.E., medical director of the Dermatology Clinical Studies Unit and assistant professor of dermatology, and associate scholar at the Center for Clinical Epidemiology and Biostatistics at the University of Pennsylvania.

Most common

Inflammation plays a key role in coronary artery disease. Immune cells dominate early atherosclerotic lesions, and their effector molecules accelerate progression of the lesions, and activation of inflammation can elicit acute coronary syndromes. CD4 and CD8 cells as well as TH-1 cytokines have been implicated in the pathogenesis of atherosclerosis and plaque rupture. Also, measures of systemic inflammation such as CRP and IL-6 are elevated in patients with myocardial infarction and can be elevated in patients with psoriasis.

"Psoriasis has been associated with a higher prevalence of cardiovascular diseases and myocardial infarction in previous studies, Dr. Gelfand tells Dermatology Times. "These studies were hospital-based and did not control for confounding variables. Data is emerging that psoriasis is associated with smoking, obesity and dyslipidemia, which are also risk factors for myocardial infarction."

In order to determine whether psoriasis is a risk factor for myocardial infarction and to determine the impact of psoriasis severity on the risk of myocardial infarction while controlling for traditional cardiovascular risk factors, Dr. Gelfand and his team of researchers conducted a population based cohort study using data collected by general practitioners participating in the General Practice Research Database (GPRD) in the United Kingdom.

Psoriasis patients were classified as severe if they ever received a systemic therapy for psoriasis. Control patients (with no history of psoriasis) were selected from the same practices and start dates as the psoriasis patients. Cox proportional hazards models were estimated, adjusting for the major cardiovascular risk factors including age, gender, diabetes, hyperlipidemia, hypertension, BMI, history of myocardial infarction, as well as smoking.

Study parameters

The study included a total of 556,995 control patients and 127,139 and 3,837 patients with mild and severe psoriasis, respectively. Patient age ranged from 20 to 90 years of age, with a mean age of 45.72, 46.35 and 49.75 for the control, mild psoriasis and severe psoriasis groups, respectively. The systemic therapies received by those patients with severe psoriasis were methotrexate (58.95 percent), azathioprine (16.39 percent), psoralen/phototherapy (16.21 percent), cyclosporine (10.27 percent), etretinate or acitretin (9.02 percent), hydroxyurea (5.79 percent) and mycophenolate mofetil (0.23 percent).

The results showed that psoriasis patients are at increased risk for myocardial infarction, independent of traditional cardiovascular risk factors. Dr. Gelfand noticed that patient age significantly modified the risk of having a myocardial infarction, young psoriasis patients with severe disease being the most at risk. For a 30-year-old patient with a mild or severe psoriasis, the adjusted relative risk of having a myocardial infarction is 1.29 and 3.10, respectively compared to patients without psoriasis. For a 60-year-old patient with a mild or severe psoriasis, the adjusted relative risk of having a myocardial infarction is 1.08 and 1.36, respectively.

Dr. Gelfand says that, "Psoriasis may be an independent risk factor for myocardial infarction, similar to other Th-1 diseases such as rheumatoid arthritis. Therefore, patients with psoriasis should get counseling regarding management of traditional cardiovascular risk factors as part of routine medical care."