Reference intervals for 12 clinical laboratory tests in a Danish population: The Lolland-Falster Health Study

Abstract

Reference intervals (RIs), developed as part of the Nordic Reference Interval Project 2000 (NORIP) are widely used in most European laboratories. We aimed to examine the validity of the NORIP RIs by establishing RIs for 12 frequently used laboratory tests based on data from a local Danish population and compare these local RIs with the NORIP RIs. Using an a posteriori direct sampling approach, blood sample data were assessed from 11,138 participants aged 18þ years in the Lolland-Falster Health Study (LOFUS), of whom 2154 turned out to meet criteria for being healthy for inclusion in establishing RIs according to the NORIP methodology. The 2.5th and 97.5th percentiles were calculated for alanine aminotransferase (ALAT), albumin, alkaline phosphatase, bilirubin, creatinine, hemoglobin, highdensity lipoprotein cholesterol, iron, low-density lipoprotein cholesterol, thrombocytes, total cholesterol, and triglycerides. When comparing our estimates with the NORIP, the lower reference limits (RLs) for bilirubin and iron were lower, and higher for ALAT, thrombocytes and triglycerides. Upper RLs were lower for albumin (males and females !70 years), bilirubin and iron, but higher for alkaline phosphatase, triglycerides and for creatinine in men. In LOFUS, approximately 20% of the participants were healthy and qualified for inclusion in the establishment of RIs. Several of the local RIs differed from the NORIP RIs.

Establishment of gender- and age-specific reference intervals for serum liver function tests among the elderly population in northeast China

“…The main findings included the facts that RIs for serum TP and ALB didn't require gender partitioning, which was consistent with national standard, Canada and Denmark (23,24). The downward tendency in serum TP concentrations may be due to the decrease in the volume and number of liver cells with age.…”

“…The Supplemental table lists the RIs obtained in this study and RIs derived from national standards (20)(21)(22). Studies in Canada, Denmark and Asmara, Eritrea were also used to compare the differences in RIs among regions (23)(24)(25). The relative deviations of the LL and UL of each analyte's RIs with the national standard and other studies were also included.…”

Lifestyle and demographic associations with 47 inflammatory and vascular stress biomarkers in 9876 blood donors

“…Although the effect of sex, age, and body mass index (BMI) on specific biomarkers has been examined in large studies 4 – 6 , these studies have reported on the presence of associations between biomarkers and various traits and not on absolute biomarker concentrations in specific subgroups. Further, studies with concentration levels for reference and comparison are relatively limited in sample sizes 7 – 9 , or only include limited numbers of biomarkers (<30) 10 – 12 . Consequently, information on expectable concentrations is scarce for plasma concentrations of biomarkers stratified by sex, age, BMI, and common lifestyle factors such as smoking, i.e., phenotypes that are not exclusive to the criteria defining a healthy individual.…”