Oral Candidiasis in Patients With Oral Lichen Planus Receiving Topical Corticosteroids: A Retrospective Cohort Study.

OBJECTIVE: To estimate the incidence and predictors of oral candidiasis in patients with oral lichen planus (OLP) treated with topical corticosteroids. METHODS: Retrospective cohort study of 312 adults with OLP followed for 487.5 person-years. The primary outcome was the first microbiologically confirmed episode of oral candidiasis. Adjusted incidence rate ratios (IRRs and rinses) were estimated using Poisson regression; Cox proportional hazards models were used for sensitivity analysis. RESULTS: Oral candidiasis occurred in 78 patients (25.0%; incidence rate 0.160 per person-year), with a median onset of 4 months. Risk peaked within the first 2 months and declined thereafter (IRR = 0.33 for 4-8 months; IRR = 0.08 for > 8 months). Higher disease severity predicted infection (highest vs. lowest quartile: IRR = 1.61; 95% CI: 1.02-2.54). Poor oral hygiene (IRR = 1.88; 95% CI: 1.13-3.13) and removable partial dentures (IRR = 1.68; 95% CI: 1.07-2.63) were independently associated. Clobetasol propionate showed a higher risk than triamcinolone acetonide (IRR = 1.48; 95% CI: 0.96-2.28); these associations remained consistent in sensitivity analysis. No associations were observed for age, sex, alcohol use or xerostomia. CONCLUSIONS: Oral candidiasis is common in corticosteroid-treated OLP. Risk is driven by disease severity and modifiable local factors, supporting targeted prevention and monitoring.