Burning Sensation and Facial Blood Flow in Rosacea Patients: An Exploration of an Invisible Symptom That Cannot Be Overlooked.

Background: Rosacea presents with visible symptoms and subjective symptoms like burning and itching; among these, burning may seriously impairs patients' quality of life. Current research has focused primarily on visible manifestations, with insufficient attention given to studying subjective symptoms such as burning. The aim of this study is to investigate the characteristics of burning, as well as the potential changes in facial blood flow of patients. Methods: A questionnaire survey and retrospective study were employed. 177 patients answered questions related to their burning sensation. Laser speckle contrast imaging was used to investigate the differences in facial blood perfusion. Results: Among 177 patients, 87.0% reported that the subtype of rosacea associated with burning was ETR, 58.8% experienced burning before their diagnosis, and the most commonly associated symptom was exacerbated erythema (85.3%). Dietary habits and behavioural practices can trigger burning. The onset of burning exhibits a certain seasonality, being most prevalent in winter (December, January, and February), and it is more likely to occur in the afternoon and during significant temperature fluctuations. Among five groups of patients matched by baseline characteristics and disease severity, four groups displayed higher facial blood perfusion in burning patients compared to non-burning patients within the same timeframe. Conclusion: Burning sensation can be influenced by specific dietary or lifestyle habits and changes in external temperature. Burning may be related to increased facial blood perfusion.