From the Guidelines
The etiology of rosacea is multifactorial, involving a combination of genetic, environmental, and physiological factors, including abnormal immune response, vascular abnormalities, and neurovascular dysregulation. Rosacea is thought to involve:
- Abnormal immune response: An overactive immune system may cause inflammation in the skin.
- Vascular abnormalities: Blood vessels in the face dilate too easily, leading to flushing and visible blood vessels.
- Demodex mites: An overgrowth of these microscopic mites that naturally live on the skin may contribute to symptoms.
- Neurovascular dysregulation: Abnormal nerve signaling may cause blood vessels to dilate excessively.
- Gastrointestinal factors: Some research suggests a link between rosacea and H. pylori infection or small intestinal bacterial overgrowth (SIBO).
- Environmental triggers: Sun exposure, hot or cold temperatures, spicy foods, alcohol, and stress can exacerbate symptoms.
- Genetics: Family history is a risk factor, suggesting a genetic component. Although the study by Schaller et al. 1 does not directly address the etiology of rosacea, it provides guidance on the management of the condition, which implies that understanding the underlying causes is crucial for effective treatment. The study highlights the importance of a phenotype-led approach to rosacea management, considering disease activity, severity, and presenting features, as well as patient education and trigger factor avoidance 1. However, the exact etiology of rosacea remains unclear, and further research is needed to fully understand the underlying mechanisms. In clinical practice, a comprehensive approach to managing rosacea should take into account the potential causes and triggers, and patients should be advised to use gentle skincare products, protect their skin from sun exposure, and identify and avoid personal triggers to manage their condition effectively.
From the Research
Etiology of Rosacea
The etiology of rosacea is complex and not fully understood. Several factors are thought to contribute to the development of the disease, including:
- Genetic predisposition 2, 3
- Environmental factors such as exposure to ultraviolet (UV) radiation, climate, and cutaneous flora 4, 5
- Abnormal vascular reactivity and vascular mediating mechanisms 4, 3
- Infection with Helicobacter pylori and infestation with Demodex folliculorum 4, 3, 5
- Seborrhea, hypertension, and psychogenic factors 3
- Dysregulation of the innate and adaptive immune system, including the release of various mediators such as cathelicidin, vascular endothelial growth factor, and endothelin-1 2, 6
Pathophysiology
The pathophysiology of rosacea involves a complex interplay of factors, including:
- Vascular and inflammatory components 4
- Innate immune system anomalies, with an increase in the expression of epidermal proteases and production of pro-inflammatory cathelicidin peptides 4
- Facial hypersensitivity and neurovascular dysfunction 4, 6
- Skin barrier and permeability dysfunction 6
Trigger Factors
Trigger factors can contribute to the initiation and aggravation of rosacea, including: