Autologous Platelet-Rich Plasma Treatment for Androgenic Alopecia: A Systematic Review and Meta-analysis of Clinical Trials on Patient Safety, Efficacy and Outcomes.

Background: Androgenic alopecia (AGA) is a common condition associated with hair loss both in men and women (female pattern hair loss, FPHL), causing considerable psychological distress. Ongoing research focuses on novel safe, cost-effective and efficient treatments with the best patient outcomes. Autologous platelet-rich plasma (PRP) has become increasingly popular in the treatment of AGA compared to hair transplantation techniques. The present study aims to evaluate the outcomes of PRP as a treatment for AGA/FPHL. Methods: A computerized literature search was conducted on PubMed, clinicaltrials.gov and Cochrane Library for articles published until November 2020. The online screening process was performed by two independent reviewers with the Covidence tool against set inclusion/exclusion criteria. The protocol was reported using PRISMA (Preferred Reporting Items for Systematic Review and Meta-Analyses), and it was registered at the International Prospective Register of Systematic Reviews (PROSPERO) of the National Institute for Health Research (NIHR). Meta-analyses were performed by employing the Random Effects Model using the RevMan software. Results: The initial search yielded 49 randomized controlled clinical trials (RCTs). Eleven RCTs were included in the study based on a priori criteria. PRP injections significantly increased the number of hair follicles, hair thickness and density compared to placebo interventions. Also, the patients reported high overall satisfaction with the PRP treatment. Only temporary minor side effects were noted, including localized pain, bleeding and itching. Conclusion: Autologous PRP significantly improves alopecia in select patients. Future research should focus on optimizing PRP treatment protocols and minimizing possible adverse reactions.