Establishing reference intervals for galectin-3 concentrations in serum requires careful consideration of its biological determinants.

BACKGROUND

Appropriately established reference intervals for laboratory biomarkers may help the interpretation of their results and facilitate clinical utilization.

OBJECTIVES

i) To determine reference intervals for serum galectin-3 measured using the Architect STAT immunoassay, and ii) to identify factors affecting galectin-3 concentrations.

METHODS

We recruited 533 questionnaire-identified apparently healthy individuals, in which laboratory biomarkers were used to detect asymptomatic myocardial injury and dysfunction, ongoing inflammation, hyperglycemia, dyslipidemia, and renal dysfunction. A final reference group of 180 subjects was selected.

RESULTS

2.5th and 97.5th percentiles of distribution of galectin-3 concentrations in the reference group (90% confidence interval) were 5.9 (5.0-6.8) and 18.1 (17.2-19.0) μg/L, respectively. Older age contributed to higher galectin-3 concentrations, but influenced derived reference intervals to a lesser extent. Other major determinants of galectin-3 concentrations observed in the questionnaire-screened population were not linked to galectin-3 in reference individuals. In aiming to decide if reference limits should be partitioned by age, we compared galectin-3 concentrations in subjects <40 (n=124) and ≥40years (n=56). Higher galectin-3 concentrations were found in older people (median, 12.4μg/L vs. 11.5μg/L, p=0.016). Accounting for manufacturer's declared imprecision at galectin-3 physiological concentrations of <10% (as CV) and the estimated URL for subjects ≥40 (18.8μg/L) and <40 (17.9μg/L), we recommend the adoption of a single URL for the overall adult population.

CONCLUSIONS

We established reference intervals for galectin-3 in which the effects of biological determinants were irrelevant. Although in healthy subjects age may affect galectin-3 release, this does not appear to necessitate age-related reference limits.