Clinical predictors of disease severity in oral lichen planus.

Background: The limited understanding of factors influencing the disease progression of oral lichen planus (OLP) poses challenges in delivering effective and personalized treatment for this condition, known to increase the risk of oral cancer and have an adverse impact on patients' quality of life.

Objectives: To systematically identify clinical predictors of disease severity in patients with OLP.

Methods: This cross-sectional and single-site prospective study was conducted between December 2021 and February 2024 in the Departments of Oral Medicine and Oral & Maxillofacial Surgery (Aberdeen Royal Infirmary, Aberdeen, UK). Patients presenting with OLP aged 18 years or older diagnosed using Van der Meij and Van der Waal criteria were eligible for the study. Out of a total of 270 eligible patients with OLP presenting consecutively to the outpatient clinics during the study period, 89 patients agreed to participate and were enrolled into the study. Participants demographic and relevant clinical data, namely medical history, smoking status, alcohol consumption, perceived stress levels, oral hygiene status and haematological and biochemical parameters, including full blood count, haematinics and vitamin D, were recorded. The outcome measure was OLP disease severity measured as the Oral Disease Severity Score (ODSS), Gingival ODSS and the Reticular/hyperkeratotic, Erosive/erythematous, Ulcerative (REU scoring system).

Results: In total, 89 participants were recruited into the study. The median age of the study population was 66 (interquartile range 58-73) years, and 65 (73%) patients were women. The median total ODSS score was 10 (range 0-44). After adjustment for confounding factors, patients with lichen planus affecting skin or other mucosal sites had a 5.76-unit higher OLP severity score [B = 5.76, 95% confidence interval (CI) = 0.74-10.78, P = 0.03] than those without extraoral involvement as measured by the ODSS. Patients with insufficient vitamin D exhibited a 5.49-unit increase in disease severity (B = 5.49, 95% CI = 1.13-9.84, P = 0.01) compared with those with adequate vitamin D levels.

Conclusions: This study identified the importance of cutaneous and/or genital lichen planus in phenotyping OLP disease severity. We also highlight the role of vitamin D as a significant predictor of disease severity of OLP, suggesting the importance of adequate vitamin D levels in patient management.