Demographic, anthropometric and intrasubject variations affect platelet-rich plasma formulation.

Abstract

The purpose of this study is to describe the inter- and intra-individual differences in the platelet concentration between blood and platelet-rich plasma (PRP) preparation, assess intersubject differences considering demographic and anthropometric variables, describe PRP code distribution and analyse intrasubject variability. A retrospective analysis was conducted using a single-centre patient database from November 2021 to November 2023. It included patients with musculoskeletal pathologies treated with PRP injections. Primary variables were demographic characteristics (sex, age, body mass index [BMI]) and platelet concentrations in blood and PRP during treatments. Secondary analysis focused on PRP code frequency distribution and intrasubject variability according to different coding systems. Here, 686 patients met the inclusion criteria. PRP exhibited significantly higher platelet concentrations compared to blood (378.01 ± 136.25 × 10³ platelets/µL vs. 221.97 ± 58.21 × 10³ platelets/µL, <i>p</i> < 0.001). Younger patients had higher platelet concentrations in both blood (<i>p</i> = 0.004) and PRP (<i>p</i> = 0.003), whereas female patients showed higher platelet concentrations only in blood (<i>p</i> < 0.001). The platelet concentration ratio was higher in males (<i>p</i> < 0.001) and those with higher BMI (<i>p</i> = 0.023). Significant differences were found between the existing and modified PRP coding systems (<i>p</i> < 0.001). Intrasubject variability was higher in PRP than in blood (coefficient of variance: 21.32 ± 17.36 in blood vs. 27.85 ± 19.10 in PRP, <i>p</i> < 0.001). Age, gender, BMI and intrasubject variations significantly affect PRP formulation, emphasizing the importance of addressing these variables for a more predictable, personalized and effective therapeutic approach. This is a retrospective study. Level IV.