Vessel resistance to blood flow in the nailfold in patients with psoriasis: a prospective case-control echo Doppler-based study.

ABSTRACT

BACKGROUND: Psoriasis is a disease in which endothelial cells seem to play an important pathogenic role. No report published to date has examined nail vascularity in patients with psoriasis. OBJECTIVES: To evaluate the vascularity in the nails of patients with psoriasis treated with classic and biologic therapies for comparison with disease-free controls, and to evaluate whether there are differences in nail vascularity among patients with and without nail involvement. METHODS: We performed a prospective study with two cohorts comprising 23 patients with moderate-to-severe psoriasis and 23 controls without psoriasis. We measured the nailfold vessel resistance index (NVRI) in each subgroup. RESULTS: We found significant differences in the NVRI between patients and controls (P<0·001). Among patients with psoriasis, those with nail involvement showed a higher mean±SD NVRI (0·58±0·10) than those without (0·52±0·45). CONCLUSIONS: Psoriasis decreases the blood flow in nails, suggesting that this skin disease confers an independent risk for microvascular changes. This outcome may be associated with greater risk of nail-related signs.