Aim: To establish the prevalence of diabetes mellitus (DM) and insulin resistance in patients with lichen planus (LP), and to examine whether diabetic status showed any relation with the type of LP.
Patients and methods: Thirty patients with LP and 30 age, weight, and sex matched volunteers were included. Serum fasting glucose, insulin, hemoglobin A1c levels were determined, a standard oral glucose tolerance test (OGTT) was performed.
Results: Of patients with LP, eight (26.7%) had DM (four newly diagnosed), however, only one (3.33%) diagnosed as DM in control group (p=0.007). Six patients (20.0%) with LP and four healthy persons (13.3%) had IGT (p>0.05). Glucose metabolism disturbance (DM+IGT) was detected in 14 (46.7%) of the patients and in 5 (16.7%) of the controls (p=0.026). HbA1c, fasting serum glucose, and insulin resistance (HOMA) were statistically higher in patients compared to controls.
Conclusion: Our finding documented that approximately one half of the patients with LP had glucose metabolism disturbance, and one fourth had DM. We believe that further studies are needed to explain this close relationship between DM and LP.