FFA and Personal Care Product Use: A Systematic Review and Meta-Analysis

Background: Frontal fibrosing alopecia (FFA) is a cicatricial alopecia affecting the frontotemporal hairline. This scarring, immune-mediated follicular destruction most commonly affects postmenopausal Caucasian women, however the exact etiology of FFA is still unknown. Recent literature has reported cases of FFA as being potentially caused by personal care product. Therefore, this systematic review and meta-analysis intends to be the first to analyze the relationship between FFA and cosmetic/personal care products and treatments, including sunscreen, moisturizer, foundation, shampoo, conditioner, hair mousse, hair gel, hair dye, hair straightening/rebonding, chemical/laser facial resurfacing, aftershave, and facial cleanser. Methods The Cochrane, PubMed, EMBASE, and Medline (Ovid) databases were searched for the relevant studies from the date of inception to August 2022. Case-control, cross-sectional, and cohort studies examining the effects of cosmetic/personal care product use on FFA, available in English full-text, were included. Analyses were performed using Review Manager, version 5.4. Results Nine studies were included in our quantitative analyses, totaling 1,248 FFA patients and 1,459 controls. There were significant positive associations found for FFA and sunscreen (OR 3.02, 95% CI 1.67–5.47; p < 0.05) and facial moisturizer (OR 2.20, 95% CI 1.51–3.20; p < 0.05) use. Gender sub-analyses demonstrated a positive association for FFA and facial moisturizer in men (OR 5.07, 95% CI 1.40-18.32; p < 0.05), but not women (OR 1.58, 95% CI 0.83–2.98; p < 0.05). There was no association found for facial cleanser (OR 1.14, 95% CI 0.33–1.52; p < 0.05), foundation (OR 1.13, 95% CI 0.83–1.55; p < 0.05), shampoo (OR 0.49, 95% CI 0.22–1.10; p < 0.05), hair conditioner (OR 0.81, 95% CI 0.52–1.26; p < 0.05), hair mousse (OR 1.37, 95% CI 0.75–2.51; p < 0.05), and hair gel (OR 0.90, 95% CI 0.48–1.69; p < 0.05), hair dye (OR 1.07, 95% CI 0.69–1.64; p < 0.05), hair straightening/rebonding (OR 0.53, 95% CI 0.01–32.76; p < 0.05), hair perming (OR 1.41, 95% CI 0.89–2.23; p < 0.05), facial toner (OR 0.51, 95% CI 0.12–2.21), or aftershave (OR 1.64, 95% CI 0.28–9.49; p < 0.05). Conclusions This meta-analysis strongly suggests that the leave-on facial products, facial sunscreen and moisturizer, are associated with FFA. There was no significant relationship found with hair products or treatments. These findings suggest a potential environmental etiology in the development of FFA, particularly UV-protecting chemicals.