Prevalence of nail changes in patients with psoriasis and correlation of NAPSI (Nail area psoriasis severity index) with BSA (Body surface area)

Introduction: Nail involvement is an often-overlooked clinical symptom of Psoriasis. It causes psychologic stress, pain, impairment of manual dexterity and a significant negative impact on a patient's quality of life. Objective: The present study was conducted to study the prevalence of nail changes in psoriasis patients, assessment of the severity of nail involvement using NAPSI score and to correlate the relationship between NAPSI and BSA in those patients. Materials and Methods: This was a cross sectional study, conducted in Dermatology department in a tertiary care hospital between January 2016-August 2017. A total of 100 psoriasis patients were included in the study. The severity of nail involvement was assessed with NAPSI. Cutaneous disease severity was assessed with BSA. Data were coded and analyzed. Results: Most common nail change in our study was Nail pitting (83.1%), followed by onycholysis (73.8%), subungual hyperkeratosis (23.1%), Longitudinal ridges (23.1%) and Beau's lines (21.5%). We observed that BSA showed a positive and statistically significant correlation with NAPSI, demonstrating worsening of nail involvement with increased severity of skin disease. Conclusion: Nail psoriasis seems to be an ignored feature of the disease and further research must focus on the effect of psoriasis treatment on the nails. This study is the first to compare NAPSI in correlation with body surface area (BSA), leading to lesser inter observer variability in assessing the severity of skin and nail involvement when compared with PASI.