An observational cross-sectional survey of rosacea: clinical associations and progression between subtypes

Summary Background Few studies have evaluated differences between rosacea subtypes in epidemiological associations and clinical features. The natural history of rosacea is unknown and progression between subtypes has been implied but not formally evaluated. Objectives To assess associations between the four rosacea subtypes [erythematotelangiectatic (ETR), papulopustular (PPR), phymatous (PHY) and ocular], including quantitative and qualitative details on primary and secondary features of rosacea. A secondary objective was to evaluate for the potential of progression between subtypes. Methods This cross‐sectional study recruited subjects with rosacea from Northern Germany and comprised clinical evaluation by a dermatologist and a survey of demographics and onset of rosacea‐associated signs and symptoms. Results A total of 135 subjects with rosacea were enrolled. PHY was more frequently associated with PPR than ETR (P