Patient Assessments of Skin, Joint, and Nail Disease Activity in Psoriatic Arthritis

To the Editor: We read with great interest the report by Cauli, et al on patient assessments of disease activity in psoriatic arthritis (PsA)1. As part of an exercise validating an instrument to assess the activity of nail psoriasis2, the modified Nail Psoriasis Severity Index (mNAPSI), we collected detailed clinical information from a cohort of 20 patients with PsA. In addition to standard measures of peripheral arthritis, functional status, quality of life, and skin psoriasis activity, this included visual analog scales (VAS) with which patients separately assessed the global activity of their PsA, as well as the activity of skin involvement, joint involvement, and nail involvement. Pairwise correlations between various outcome measures were performed … E-mail: akavanaugh{at}ucsd.edu