Prevalence of frontal fibrosing alopecia among Brazilian dermatologists: A cross-sectional survey

The Frontal Fibrosing Alopecia Treatment Dilemma

Frontal fibrosing alopecia (FFA) is a type of cicatricial alopecia predominantly observed in postmenopausal women, with the incidence rising since its initial description in 1994. The exact etiopathogenesis of the disease has not been completely elucidated. FFA is characterized by an inflammatory process affecting the hair follicles of the fronto-temporal hairline, leading to its gradual recession. Eyebrows, particularly the lateral parts, may also be affected. Early diagnosis and an implementation of effective therapy to limit the inflammatory process are crucial in halting disease progression. Various treatment possibilities have been reported, including anti-inflammatory and immunosuppressive agents, as well as 5-alpha-reductase inhibitors, retinoids, and antimalarial agents. The use of phototherapy and surgical procedures has also been described. However, most available data have been obtained retrospectively, frequently consisting of descriptions of case reports or small case series, and not from randomized controlled trials. In addition, the etiopathogenesis of FFA remains unclear and its course unpredictable, occasionally being linked with spontaneous stabilization. Hence, no precise guidelines exist regarding treatment modalities. Therefore, the aims of this study were to provide a comprehensive review of the efficacy of existing therapeutic modalities for FFA and to highlight novel therapeutic options.

Association between frontal fibrosing Alopecia and Rosacea: Results from clinical observational studies and gene expression profiles

Background

In recent years, frontal fibrosing alopecia (FFA), a type of scarring alopecia, has attracted increasing attention. Several studies have reported the frequent occurrence of rosacea in FFA; however, the association between FFA and rosacea and the underlying pathogenesis have not been thoroughly clarified. Thus, this study aimed to quantify these relationships and investigate their shared molecular mechanisms.

Methods

We evaluated the association between FFA and rosacea by analyzing clinical data from nine observational studies. We then analyzed the gene expression profiles of FFA and rosacea. First, differential expression analysis and weighted gene co-expression network analysis were used to identify the common differentially expressed genes (DEGs). Later, we conducted a functional enrichment analysis and protein-protein interaction network and used seven algorithms to identify hub genes. Then, we performed a correlation analysis between the hub genes and the gene set variation analysis scores of common pathways in the gene set enrichment analysis (GSEA). The results were validated using different datasets. Finally, transcription factors were predicted and verified, and CIBERSORT and single-sample GSEA were used to estimate the infiltrating immune cells.

Results

Patients with FFA had significantly higher odds for rosacea (pooled odds ratio [OR], 2.46; 95% confidence interval [CI], 1.78–3.40), and the pooled prevalence of rosacea in patients with FFA was 23% (95% CI, 14–23%). Furthermore, we identified 115 co-DEGs and 13 hub genes (CCR5, CCL19, CD2, CD38, CD83, CXCL8, CXCL9, CXCL10, CXCL11, CXCR4, IRF1, IRF8, and PTPRC). Seven pathways showed a high correlation with these hub genes. In addition, one TF, STAT1, was highly expressed in both diseases, and the results of the immune infiltration analysis indicated the importance of M1 macrophages and effector memory CD8+ T cells.

Conclusion

This study contributes to the understanding of the relationship between FFA and rosacea, and based on the hub genes, we reveal the potential pathologies shared by the two diseases. This finding provides new insights of underlying molecular mechanisms and it may inspire future research on this comorbidity.