TNF Inhibitors Reduce Myocardial Infarction in Psoriasis Patients

New Orleans—A large retrospective cohort study found that taking tumor necrosis factor (TNF) inhibitors to treat psoriasis was associated with a significant reduction in the risk of myocardial infarction (MI) compared with not taking TNF inhibitors. In addition, patients who took TNF inhibitors were 28.2% less likely to experience MI compared with patients who took oral therapies or phototherapies, although the difference was not statistically significant. The results were presented at the AAD meeting during a poster discussion session titled The Effect of Tumor Necrosis Factor-Alpha Inhibitors on the Risk of Myocardial Infarction in Patients with Psoriasis. Jashin J. Wu, MD, founding director of clinical research and founding associate program director in the dermatology department at the Kaiser Permanente Los Angeles Medical Center, was the study’s lead author. Psoriasis, a chronic skin condition, affects approximately 2% to 3% of the US population and has been associated with a risk of cardiovascular events. Patients who have psoriasis have a few therapeutic options, including methotrexate, which has been found to reduce cardiovascular events. However, oral retinoids and cyclosporine may exacerbate dyslipidemia and hypertension, according to the authors. The authors were interested in determining if TNF inhibitors were beneficial in reducing the risk of cardiovascular events in psoriasis patients. They examined >24,000 patients who had psoriasis and were members of Kaiser Permanente Southern California (KPSC), a managed healthcare plan. They used data from January 1, 2004, through December 31, 2008, during which KPSC provided health services to >3.6 million patients. Patients were included in the study if they had International Classification of Diseases, Ninth Revision codes for psoriasis or psoriatic arthritis ≥3 times before December 31, 2008, had been enrolled in Kaiser Permanente for ≥2 years, and had ≥1 medical encounter per year. They were excluded if they had MI before January 1, 2004. The authors divided the 24,081 patients into 3 categories. Baseline characteristics for the groups were similar. The TNF cohort included 1877 patients who received ≥2 consecutive months of the same TNF inhibitor (either adalimumab, etanercept, infliximab, or golimumab). The oral/photo cohort included 2961 patients who received oral therapies (cyclosporine, acitretin, or methotrexate) or phototherapies (broadband ultraviolet B, narrowband ultraviolet B, or psoralen plus ultraviolet A). The mild cohort included 19,243 patients who were not treated with TNF inhibitors, oral therapies, or phototherapies. The patient outcomes were followed until November 30, 2010, and concluded when patients developed the outcome, died, or stopped enrolling at KPSC. The authors examined the following cardiac risk factors: type 2 diabetes, hypertension, dyslipidemia, smoking, and body mass index. They also examined statins, beta-blockers, and methotrexate, which are known to reduce MI. In addition, they implemented univariate and multivariate analyses to determine the variables that are associated with MI. Patients in the TNF group had a significant reduction in MI (P<.05). When compared with the mild group, the TNF group also had a 44.3% reduction in MI incidence, which was statistically significant (P=.0016). Patients taking oral therapies or phototherapies were 22.4% less likely to have an incidence of MI compared with the mild group, but the difference was not statistically significant (P=.0709). The authors noted a few limitations to the study. It was not a prospective trial, so the authors could not determine a causal effect. In addition, the relatively short follow-up period could have contributed to a decreased ability to determine a significant reduction in MI between the TNF group and patients taking oral therapies and phototherapies. Finally, the small number of people (4838) used to compare incidence rate ratios in the TNF group and the oral therapies/phototherapies cohort led to a loss of power to detect statistical significance.