Most Frequent Comorbidities in Patients With Lichen Planopilaris: A Cross-Sectional Study

Objective: Lichen planopilaris (LPP) is a rare skin disorder, but it is also the most common cause of scarring alopecia in adults. The main cause of this disease is unknown, but it is considered to be related to the immune status of the body. Several comorbidities are reportedly associated with LPP, such as hypertension, depression, thyroiditis, diabetes, and vitiligo. In the present study, we aimed to investigate the frequency of comorbidities in patients with LPP who were referred to Razi Hospital in Rasht, Iran, from 2016 to 2019.Methods: This cross-sectional study involved 60 patients with cicatricial alopecia patches (scarring and irreversible) and clinical signs and symptoms consistent with active LPP. The association between demographic data and comorbidities in patients with LPP was evaluated with the chi-square test andt test.Results: The results showed that the most common comorbidities were vitamin D deficiency (24.3%), hypothyroidism (17.6%), anemia (16.2%), asthma and allergy (14.8%), hypertension (13.5%), diabetes (9.5%), and vitiligo (4.5%). There was no statistically significant association of sex, age, or body mass index with LPP according to the presence or absence of underlying disease (P = 0.440,P = 0.108, andP = 0.340, respectively); however, there was a statistically significant difference in the presence of comorbidities according to age (P = 0.018).Conclusion: The results illustrated that women with vitamin D deficiency are more prone to LPP than are patients with other pre-existing underlying diseases.