Neutrophil‐to‐lymphocyte ratio and the systemic immune‐inflammation index as potential biomarkers of effective treatment and subclinical atherosclerotic cardiovascular disease in patients with psoriasis

The objective of this retrospective study is to assess neutrophil to lymphocyte ratio (NLR) and platelet to lymphocyte ratio (PLR) as inflammatory markers in patients with psoriasis and psoriatic arthritis (PsA). A hundred and eleven psoriasis patients and 25 PsA patients were compared with 94 healthy controls. Demographic, clinical and laboratory information were collected and analyzed. NLR and PLR were calculated. White blood cell (WBC), neutrophils, eosinophils and NLR were increased in psoriasis patients compared with controls. WBC, neutrophils, NLR, monocytes, platelets and PLR were increased in PsA patients compared with both controls and psoriasis patients. Erythrocyte sedimentation rate (ESR) and C-reactive protein were significantly higher in PsA patients compared with psoriasis patients. Among psoriasis patients, Psoriasis Area and Severity Index (PASI) score correlated positively with platelets, NLR and PLR. These parameters were all significantly higher in moderate to severe psoriasis patients (PASI ≥ 10) compared with mild patients (PASI < 10). Elevated platelets, NLR and PLR were significantly associated with the increased PASI scores in multivariate analysis. NLR, PLR and ESR were statistically significant predictors for the presence of PsA in psoriasis patients. NLR was the strongest predictor (odds ratio = 3.351, P = 0.005). In conclusion, elevated NLR and PLR were significantly associated with psoriasis and PsA. Both NLR and PLR were strong predictors for the presence of PsA among psoriasis patients.

Psoriasis is a chronic inflammatory skin disease that affects 2% to 3% of the U.S. population. The immune response in psoriasis includes enhanced activation of T cells and myeloid cells, platelet activation, and up-regulation of interferons, tumor necrosis factor-α, and interleukins (ILs) IL-23, IL-17, and IL-6, which are linked to vascular inflammation and atherosclerosis development. Patients with psoriasis are up to 50% more likely to develop cardiovascular disease (CV) disease, and this CV risk increases with skin severity. Major society guidelines now advocate incorporating a psoriasis diagnosis into CV risk prediction and prevention strategies. Although registry data suggest treatment targeting psoriasis skin disease reduces vascular inflammation and coronary plaque burden, and may reduce CV risk, randomized placebo-controlled trials are inconclusive to date. Further studies are required to define traditional CV risk factor goals, the optimal role of lipid-lowering and antiplatelet therapy, and targeted psoriasis therapies on CV risk.