Reference intervals for serum sphingosine-1-phosphate in the population-based Study of Health in Pomerania

BACKGROUND: The bioactive signaling lipid sphingosine-1-phosphate (S1P) is a potential biomarker for cardiovascular disease (CVD). To date, no reference intervals for S1P have been defined. This study aims to establish a reference range for serum S1P in healthy individuals.

METHODS: We determined reference intervals for S1P levels according to gender and age in a sample of 1339 healthy participants of the Study of Health in Pomerania (SHIP)-TREND cohort after exclusion of subjects with CVD, diabetes mellitus, hypertension, metabolic syndrome, elevated liver enzymes, chronic kidney disease stadium III or IV, or body mass index (BMI)>30kg/m(2). Serum S1P was measured by liquid chromatography-tandem mass spectrometry.

RESULTS: The median age of the participants was 41 (25th; 75th percentile 32; 51) years, 65% were women. The median serum concentration of S1P was 0.804 (0.694; 0.920) μmol/L. No association with gender and age was observed. The overall reference interval was 0.534-1.242μmol/L (2.5th; 97.5th percentile). Further exclusion of smokers, individuals with BMI>25kg/m(2) or elevated lipid levels did not significantly affect median S1P concentrations.

CONCLUSIONS: This study provides reference intervals for serum S1P in healthy individuals. Total serum S1P concentrations vary irrespectively of age, gender, BMI or smoking status.