A Meta-analysis On Evidence Of Platelet-rich Plasma for Androgenetic Alopecia.

Platelet-rich plasma (PRP) treatment has gained popularity among different surgical specialities for improving various conditions. Androgenetic alopecia (AGA) is a common disorder, with possible psychosocial implications. Plastic surgeons have increased the practice of PRP injections for hair restoration. A meta-analysis on this topic was performed comparing local injection of PRP versus control to investigate the efficacy of local PRP injections in AGA. We performed a systematic literature search. The increase in number of hairs was the primary outcome. Secondary outcomes were the increase of hair thickness and the percentage increase in hair number and thickness. Seven studies involving 194 patients were retrieved and included in the present analysis. A significantly locally increased hair number per cm <sup>2</sup> was observed after PRP injections versus control (mean difference [MD] 14.38, 95% confidence interval [CI] 6.38-22.38, P < 0.001). Similarly, a significantly increased hair thickness cross-section per 10 <sup>-4</sup> mm <sup>2</sup> (MD 0.22, 95% CI 0.07-0.38, P = 0.005) favoring PRP group. The pooled results did not show a significant percentage increase in hair number (MD 18.79%, 95% CI - 8.50-46.08, P = 0.18), neither hair thickness (MD 32.63%, 95% CI - 16.23-81.48, P = 0.19) among patients treated with PRP. Local injection of PRP for androgenic alopecia might be associated with an increased number of hairs in the treated areas with minimal morbidity, but there is clearly a lack of scientific evidence on this treatment modality. Further studies are needed to evaluate the efficacy of PRP for AGA