Establishment of the reference interval for serum pro-gastrin-releasing peptide in healthy adults of Chinese Han ethnicity

Objective: The aim of this study is to establish the reference interval for serum pro-gastrin-releasing peptide (proGRP) determined by electrochemiluminescence immunoassay (ECLIA) in healthy Chinese Han ethnic adults. Methods: After screening, 9932 healthy Chinese Han adults (age range 18-95 years) were enrolled in this study, including 6220 men and 3712 women. Serum proGRP levels were measured by ECLIA. The reference interval was defined by non-parametric 95th percentile interval. Results: Serum proGRP levels conformed to a non-Gussian distribution. The reference interval for healthy Chinese Han adults calculated by the non-parametric method was 0-73.90 ng/mL in this study. Since serum proGRP levels were significantly correlated with age (r=0.226, P<0.001), the participants were divided into six age groups: 18-39, 40-49, 50-59, 60-69, 70-79, and > 80 years. No significant difference for serum proGRP levels was found between the sexes at each of six age groups. The reference intervals were gradually increased with age (65.35 ng/mL, 68.65 ng/mL, 74.10 ng/mL, 77.65 ng/mL, 84.57 ng/mL, and 98.03 ng/mL in 18-39, 40-49, 50-59, 60-69, 70-79, and > 80 years, respectively). Conclusions: We established the reference interval for serum proGRP, which was determined by ECLIA in the healthy Chinese Han population. Furthermore, our study suggests that it is necessary to establish the age-specific reference intervals for serum proGRP.