Onychogryphosis Is Associated with Dermatologic and Vascular Disease: A Case-Control Study of the All of Us Research Program.

Introduction: Onychogryphosis is a nail condition characterized clinically by a thickened, curved, yellow-brown, and opaque nail plate and may result in pain, paronychia, and onychogryphosis.

Methods: We performed a nested case-control study of 1,114 onychogryphosis patients and 3,423 matched controls to quantify the association between onychogryphosis and self-care limitations, chronic foot injury, dermatologic conditions, and vascular disease.

Results and conclusion: Onychogryphosis was positively associated with increased age, activity limitations (difficulty running errands alone, bathing, and concentrating), psoriasis, onychomycosis, hallux malleus, hallux valgus, peripheral vascular disease, lower extremity ulcers, venous varices, and type II diabetes mellitus. Therefore, physicians should screen patients presenting with onychogryphosis for these conditions.