Biostimulants in aesthetic medicine: a systematic review and meta-analysis of efficacy, safety, and patient satisfaction

<p dir="ltr">Biostimulants, including calcium hydroxyapatite (CaHA), poly-L-lactic acid (PLLA), and polycaprolactone (PCL), have become popular in aesthetic medicine as they lead to long-term tissue rejuvenation. However, their efficacy (e.g. dermal, volume, and anatomic outcomes), satisfaction and safety remain unclear. This systematic review and meta-analysis collates and appraises the available data on biostimulants, examining their efficacy, adverse events and patient satisfaction. A comprehensive search was conducted in PubMed/Medline (National Library of Medicine, Bethesda, MD), Scopus (Elsevier, Amsterdam, the Netherlands), Embase (Elsevier), and Web of Science (Clarivate, Philadelpha, PA, USA), up to January 14^th, 2025. Studies were included that assessed the effects of biostimulants on efficacy, adverse events and patient satisfaction in observational studies. Meta-analyses using random-effects models were performed on individual proportions and applied to seven outcomes (satisfaction, bruising, ecchymosis, edema, erythema, nodules development, pain). A total of 197 articles were screened, and 25 studies were included in the systematic review. The results of meta-analyses indicate that the pooled satisfaction rate of biostimulants was estimated at 91% (95% CI: 67-98, <i>I</i>^<em>2</em>= 87.3%); bruising 27% (95% CI: 12-50, <i>I</i>^<em>2</em>= 96%), ecchymosis 22%; (95% CI: 11-40, <i>I</i>^<em>2</em>= 95.5%), edema 5%; (95% CI: 1-18, <i>I</i>^<em>2</em>= 93.6%), erythema 16% (95% CI: 4-47, <i>I</i>^<em>2</em>= 94.3%), nodules development 5% (95% CI: 2-10, <i>I</i>^<em>2</em>= 85.5%), pain 92% (95% CI: 63-99, <i>I</i>^<em>2</em>= 87.7%,). Among studies not included in the meta-analysis all parameters studied showed significant improvements in terms of dermal, volume, anatomic and satisfaction outcomes. Biostimulants demonstrate clinical promise and a favourable tolerability profile in aesthetic medicine, despite the common occurrence of minor adverse events, most notably pain</p>