Italian patients with oral lichen planus: A cross-sectional study from the SIPMO

Aim: Oral Lichen Planus (OLP) is an immune-mediated inflammatory chronic disease of the oral mucosa, with different patterns of clinical manifestations. The aim of the study was to analyse the differences in the clinical and psychological profile of keratotic oral lichen planus (K-OLP) and non-keratotic oral lichen planus (nK-OLP) patients from the North vs Central-South regions in Italy. Methods: OLP patients were recruited in 15 Italian universities joined with the Italian Society of Oral Pathology and Medicine (SIPMO- Società Italiana di Patologia e Medicina Orale). The Numeric Rating Scale (NRS), Total Pain Rating Index (T-PR1), Hamilton Rating Scales for Depression and for Anxiety (HAM-D and HAM-A), Pittsburgh Sleep Quality Index (PSQl), and Epworth Sleepiness Scale (ESS) were administered. Results: a total of 540 participants were included, 270 OLP patients from the North Italian area and 270 OLP patients from the Central-South. Both groups were equally composed of 135 K-OLP and 135 nK-OLP patients. The Central-South K- OLP (CS-K-OLP) patients reported a higher frequency of pain/burning compared with the K-OLP patients of the North (N-K-OLP) {NRS and T-PRI p-values < 0.001). The CS-OLP patients showed higher levels of anxiety, depression and a poor quality of sleep compared to the Northern patients (HAM-D, HAM-A, PSQl, p-value < 0.001). Regression analyses revealed that the NRS and TPR1 showed the greatest increase in the R2 value for the CS-K-OLP (DR2 = 9.6 %; p-value < 0.001"; DR2=9.7% p-value < 0.001; respectively) and that the oral symptoms and PSQl showed the greatest increase in the R2 value for the CS-nK-OLP (DR2 = 5.6 %; p-value < 0.001; DR2 = 4.5 % p-value < 0.001). Conclusions: OLP patients from the Central-South regions present higher levels of pain and a greater impact of mood di-sorders compared to patients coming from the North. Clinicians should consider that the geographical living area may explain the differences in oral symptoms and psychological profile in OLP.