Frontal Fibrosing Alopecia and Sunscreen Use: A Cross-sectional Study of Actinic Damage.

Patients with frontal fibrosing alopecia report higher rates of sunscreen use than control subjects. However, it is not known whether the higher use of sunscreens is a cause or a consequence of the alopecia. A greater use of sunscreens should be associated with a lower incidence of signs of actinic damage. The aim of this study is to assess the presence of actinic damage in patients with frontal fibrosing alopecia. A cross-sectional study was carried out on 101 patients with frontal fibrosing alopecia and 40 control subjects. The presence of actinic damage, in the form of solar lentigines, actinic keratoses, and basal and squamous cell carcinomas, was recorded in both groups, together with sunscreen use. Trichoscopy and skin biopsy were performed on patients. Actinic damage was present more frequently in patients with frontal fibrosing alopecia (69.3%) than in control subjects (50%) (p = 0.031). Patients used sunscreens more frequently than did control subjects (83.2% vs 62.5%, p = 0.008). However, the prevalence of trichoscopic inflammatory signs, peripheral alopecia, and inflammatory infiltrate and sebaceous gland involvement in skin biopsy, were similar in patients who used sunscreens and those who did not use them. In conclusion, patients with frontal fibrosing alopecia had greater actinic damage than did control subjects, and this is hypothesized as a reason for the higher use of sunscreens among patients. Thus, use of sunscreens may not be the trigger for frontal fibrosing alopecia that dermatologists have proposed.

Frontal Fibrosing Alopecia: A Histopathological Comparison of the Frontal Hairline with Normal-Appearing Scalp.

Frontal fibrosing alopecia is characterized by the presence of a lymphocytic inflammatory infiltrate around the upper follicle and by perifollicular fibrosis, which results in the destruction of the hair follicle. Recent reports have also found the presence of those findings in clinically unaffected areas. The aim of this report is to perform a deeper analysis of the histopathological features of this apparently unaffected scalp. A cross-sectional study including 52 women with frontal fibrosing alopecia was performed. Two areas were biopsied: the frontal hairline and a normal-appearing scalp area. Sebaceous glands were reduced/absent in 80.8% of the frontal hairline samples compared to 42.3% of the "healthy scalp" samples (p = 0.001). Inflammatory infiltrate was observed in 92.3% of patients in the frontal hairline and in 86.5% of them in the "healthy scalp" area (p = 0.508), although the severity was higher in the former (p = 0.013). Follicular epithelium changes were seen in 70.6% of the frontal hairline biopsies compared to 48.1% of the "healthy scalp" biopsies (p = 0.012). Fibrous tissular changes were noted in 80.8% and 53.8% of the frontal hairline and "healthy scalp" biopsies, respectively (p = 0.003). In conclusion, the histopathological features of frontal fibrosing alopecia are shared by both affected and clinically unaffected areas.