Platelet-rich plasma for androgenetic alopecia: Does it work? Evidence from meta analysis

The use of platelet-rich plasma (PRP) has increased among different surgical specialities for the treatment of various conditions. Androgenetic alopecia is a common condition, with severe attendant psychosocial implications. PRP injections for hair restoration have become a popular practice among plastic surgeons. We performed a meta-analysis comparing local injection of platelet-rich plasma versus control to evaluate this issue in order to investigate the effectiveness of PRP local injections for androgenetic alopecia.

A systematic literature search was performed. Primary outcome was the increase in number of hairs. Secondary outcomes were the increase in hair thickness and the percentage increase in hair number and thickness. We performed random-effect analysis.

Six studies involving 177 patients were retrieved and included in the present analysis. A significantly locally increased hair number per cm² was observed after PRP injections versus control (mean difference (MD) 17.90, 95%CI 5.84-29.95, P=.004). Similarly, a significantly increased hair thickness cross section per 10^-4  mm² (MD 0.22, 95%CI 0.07-0.38, P=.005) favoring PRP group. The pooled results did not show statistically significant differences in percentage increase in hair number (MD 24.12%, 95%CI -12.76-60.99, P=.20) and 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 and some hair thickness improvement in the treated areas with minimal morbidity. The results of this meta-analysis should be interpreted with caution as it consists of pooling many small studies. Larger randomized studies can verify this perception.