In Search of Normality for Vitamin K1: Establishing Age-Dependent Reference Intervals in the Danish Population

2020 ◽  
Vol 5 (3) ◽  
pp. 531-543
Author(s):  
Ida Boegh Andersen ◽  
Claus Lohman Brasen ◽  
Anne Schmedes ◽  
Ivan Brandslund ◽  
Jonna Skov Madsen
Keyword(s):  
Vitamin K ◽  
Serum Vitamin ◽  
Reference Intervals ◽  
Specific Reference ◽  
Vitamin K1 ◽  
Serum Samples ◽  
Lower Serum ◽  
Limit Of Quantitation ◽  
Significant Difference ◽  
Age Dependent

Abstract Background A growing body of evidence suggests that vitamin K has beneficial effects on human health, especially cardiovascular and bone health. Vitamin K1 (phylloquinone), the predominant form of vitamin K in blood, is regarded as an indicator of vitamin K status, but to our knowledge no reference intervals (RIs) have been established for vitamin K1. Methods In this population-based study, vitamin K1 was measured in serum from 3808 Caucasian individuals without diabetes from 26 to 78 years of age. The need for gender- and age-partitioned vitamin K1 reference intervals was evaluated using Lahti’s method, and exclusion criteria were defined to obtain as healthy a study group as possible. The excluded subgroups were tested for differences in mean serum vitamin K1 levels. Serum vitamin K1 levels were quantified using an in-house newly developed, validated, and highly sensitive online SPE-LC-MS/MS method with a limit of quantitation of (LOQ) 0.05 nmol/L. Results The reference interval for serum vitamin K1 was 0.22 to 3.95 nmol/L for individuals aged 26 to 44 years and 0.35 to 3.70 nmol/L for individuals aged 45 to 78. Similar age-specific reference intervals were established for vitamin K1-triglyceride ratio being 0.20 to 3.16 and 0.31 to 3.44, respectively. No significant difference was found between genders. Serum vitamin K1 was detectable in all serum samples. Individuals with known comorbidity were found to have significantly lower serum vitamin K1 compared to those without comorbidity. Current smokers had lower serum vitamin K1 compared to nonsmokers. Conclusion Age-dependent reference intervals were established for serum vitamin K1 and vitamin K1-triglyceride ratio in a well-defined, healthy Caucasian population. Lower serum vitamin K1 levels were found in individuals with known comorbidity, suggesting an association between serum vitamin K1 and disease status. Further studies are needed to determine an optimal serum vitamin K1 level.

scholarly journals Nomogram of age-specific anti-Müllerian hormone levels in healthy Egyptian females

PLoS ONE ◽  
2021 ◽  
Vol 16 (7) ◽  
pp. e0254858
Author(s):  
Eman Ahmed El-Attar ◽  
Tamer A. Hosny ◽  
Kiyoshi Ichihara ◽  
Rania N. Bedair ◽  
Ahmed Salah El-Din Tork
Keyword(s):  
Reference Interval ◽  
Reference Intervals ◽  
Specific Reference ◽  
Clinical Settings ◽  
Power Transformation ◽  
Serum Samples ◽  
Female Age ◽  
Age Related ◽  
Age Dependent ◽  
Age Range

Background Anti-Müllerian hormone (AMH) is an important determinant of ovarian reserve in fertility workups in many clinical settings. Thus, we investigated the age dependent decline in AMH specific to the Egyptian population and sought to establish an age dependent reference interval parametrically. Methods Serum samples were collected from 841 apparently healthy women. AMH was measured using an electro-chemiluminescent technique. Box-Cox power transformation was used to make the AMH distribution Gaussian for parametric derivation of reference intervals. Results Power of 0.4 was found optimal for Gaussian transformation of AMH reference values. We demonstrate the strong negative relation between circulating AMH and female age with Spearman’s correlation coefficient of rS = −0.528. Age-specific reference interval was determined for every 5 years of age from 16 to 49, and nomogram was constructed by smoothing the lines connecting adjacent lower and upper reference limits. Conclusion The age-specific reference intervals and the age-AMH nomogram could be valuable in the clinical practice of in reproductive medicine. To our knowledge, this is the first study to confirm AMH levels in Egyptian females. We were able to explore age-related AMH levels specific to Egyptian females in the fertile age group and to treat skewed AMH data in a multi-step scheme using power transformation. Thus, a more accurate nomogram was constructed accommodating a profile delineated for a wide age range and a rescaled AMH axis improving its usability.

Reference Intervals for Serum Alpha-Fetoprotein and Carcinoembryonic Antigen in Chinese Han Ethnic Males from the Fangchenggang Area Male Health and Examination Survey

2011 ◽  
Vol 26 (1) ◽  
pp. 65-71 ◽  
Author(s):  
Xue Qin ◽  
Liwen Lin ◽  
Zengnan Mo ◽  
Hui Lv ◽  
Yong Gao ◽  
...  
Keyword(s):  
Carcinoembryonic Antigen ◽  
Reference Intervals ◽  
Alpha Fetoprotein ◽  
Male Health ◽  
Significant Difference ◽  
Reference Limits ◽  
Age Dependent ◽  
Serum Alpha Fetoprotein ◽  
Serum Cea ◽  
Normally Distributed

Objectives We calculated upper 95% reference limits for serum alpha-fetoprotein (AFP)and carcinoembryonic antigen (CEA) according to the CLSI/NCCLS C28-A3 guideline. Material and methods Serum samples from 1400 healthy male subjects were collected from the Fangchenggang Area Male Health and Examination Survey (FAMHES). Serum AFP and CEA values were measured by electrochemiluminescence immunoassay on COBAS 6000 system E601 (Elecsys module) immunoassay analyzers. Results Serum AFP and CEA values were not normally distributed but log normally distributed. The upper 95% reference limits of the reference intervals were ≤4.76 IU/mL (nonparametric) or ≤4.56 IU/mL (parametric) for AFP and ≤5.57 ng/mL (nonparametric) or ≤5.82 ng/mL (parametric) for CEA. The distribution of AFP levels was found to be consistent between the non-smoking and smoking (p=0.740) and non-drinking and drinking groups (p=0.698). The distribution of serum CEA levels was significantly higher in the smoking than the non-smoking group (p<105), whereas there was no significant difference in this respect between the non-drinking and drinking groups (p=0.147). A significant increase with age was found both for serum AFP and CEA levels, and the age-dependent reference intervals were calculated. Conclusions The reference intervals for serum AFP and CEA show a slight deviation compared to previously reported reference levels. Distinct reference intervals of serum CEA must be established for smoking and non-smoking populations. In addition, age-dependent reference intervals should be implemented in clinical laboratories.

Pediatric reference intervals for 1,25-dihydroxyvitamin D using the DiaSorin LIAISON XL assay in the healthy CALIPER cohort

2018 ◽  
Vol 56 (6) ◽  
pp. 964-972 ◽  
Author(s):  
Victoria Higgins ◽  
Dorothy Truong ◽  
Nicole M.A. White-Al Habeeb ◽  
Angela W.S. Fung ◽  
Barry Hoffman ◽  
...  
Keyword(s):  
Children And Adolescents ◽  
Critical Role ◽  
Reference Interval ◽  
Reference Intervals ◽  
Biologically Active ◽  
Specific Reference ◽  
Healthy Children ◽  
Serum Samples ◽  
Dihydroxyvitamin D ◽  
1,25 Dihydroxyvitamin D

Abstract Background: 1,25-dihydroxyvitamin D (1,25(OH)2D), the biologically active vitamin D metabolite, plays a critical role in calcium and phosphate homeostasis. 1,25(OH)2D is measured to assess calcium and phosphate metabolism, particularly during periods of profound growth and development. Despite its importance, no reliable pediatric reference interval exists, with those available developed using adult populations or out-dated methodologies. Using the fully automated chemiluminescence immunoassay by DiaSorin, we established 1,25(OH)2D pediatric reference intervals using healthy children and adolescents from the CALIPER cohort. Methods: Serum samples from healthy subjects (0 to <19 years) were analyzed for 1,25(OH)2D using the DiaSorin LIAISON XL assay and age-specific reference intervals were established. The Mann-Whitney U-test was used to determine seasonal differences. Pooled neonatal and infantile samples were quantified using liquid chromatography tandem mass spectrometry (LC-MS/MS) to determine if elevated concentrations during the first year of life may be attributed to cross-reacting moieties. Results: Three reference interval age partitions were required with highest levels in subjects 0 to <1 year (77–471 pmol/L), which declined and narrowed after 1 year (113–363 pmol/L) and plateaued at 3 years (108–246 pmol/L). 1,25(OH)2D concentration was not significantly affected by seasonal variation or sex. Elevated 1,25(OH)2D concentrations in neonatal and infantile samples may be the result of an interfering substance. The absence of 3-epi-1,25-dihydroxyvitamin D in the pooled samples makes it unlikely to be the interfering moiety. Conclusions: Pediatric reference intervals for 1,25(OH)2D were established to improve test result interpretation in children and adolescents. 1,25(OH)2D is elevated in a proportion of neonates and infants, which may be the result of a cross-reacting moiety.

Distribution of HOMA-IR in a population-based cohort and proposal for reference intervals

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Bassel Matli ◽  
Andreas Schulz ◽  
Thomas Koeck ◽  
Tanja Falter ◽  
Johannes Lotz ◽  
...  
Keyword(s):  
Insulin Resistance ◽  
Fasting Glucose ◽  
Reference Group ◽  
Reference Interval ◽  
Population Based ◽  
Reference Intervals ◽  
Health Study ◽  
Specific Reference ◽  
Model Assessment ◽  
Significant Difference

Abstract Objectives Insulin resistance (IR) is a hallmark of type 2 diabetes mellitus (DM). The homeostatic model assessment of insulin resistance (HOMA-IR) provides an estimate for IR from fasting glucose and insulin serum concentrations. The aim of this study was to obtain a reference interval for HOMA-IR for a specific insulin immunoassay. Methods The Gutenberg Health Study (GHS) is a population-based, prospective, single-center cohort study in Germany with 15,030 participants aged 35–74 years. Fasting glucose, insulin, and C-peptide were available in 10,340 participants. HOMA-IR was calculated in this group and three reference subgroups with increasingly more stringent inclusion criteria. Age- and sex-dependent distributions of HOMA-IR and reference intervals were obtained. In a substudy three insulin assays were compared and HOMA-IR estimated for each assay. Results Among the 10,340 participants analyzed there were 6,590 non-diabetic, 2,901 prediabetic, and 849 diabetic individuals. Median (interquartile range [IQR]) HOMA-IR was 1.54 (1.13/2.19), 2.00 (1.39/2.99), and 4.00 (2.52/6.51), respectively. The most stringently selected reference group consisted of 1,065 persons. Median (IQR) HOMA-IR was 1.09 (0.85/1.42) with no significant difference between men and women. The 97.5th percentile was 2.35. There was a non-significant trend towards higher values with older age. Comparison of three immunoassays for insulin showed an unsatisfactory correlation among the assays and systematic differences in calculated HOMA-IR. Conclusions We present HOMA-IR reference intervals for adults derived by more or less stringent selection criteria for the reference cohort. In addition we show that assay specific reference intervals for HOMA-IR are required.

scholarly journals Early pregnancy reference intervals; 29 serum analytes from 4 to 12 weeks’ gestation in naturally conceived and uncomplicated pregnancies resulting in live births

2019 ◽  
Vol 57 (12) ◽  
pp. 1956-1967 ◽  
Author(s):  
Jesper Friis Petersen ◽  
Lennart J. Friis-Hansen ◽  
Andreas Kryger Jensen ◽  
Anders Nyboe Andersen ◽  
Ellen C.L. Løkkegaard
Keyword(s):  
Pregnant Women ◽  
Early Pregnancy ◽  
Clinical Chemistry ◽  
Clinical Care ◽  
Local Population ◽  
First Trimester ◽  
Reference Intervals ◽  
Specific Reference ◽  
Cancer Antigen 125 ◽  
Serum Samples

Abstract Background Pregnancy introduces major physiological changes that also alter biochemical analytes. Maternal and perinatal health can be optimized by early intervention and therefore, pregnancy-specific reference intervals (RIs) for the local population are warranted. While the second and third trimester-specific changes are well described, the first trimester is less well characterized. We therefore wanted to facilitate early detection of abnormalities by generating first trimester reference values for 29 common analytes. Methods In a prospective early pregnancy (PEP) cohort (2016–2017), 203 pregnant women were recruited from 4 to 8 weeks’ gestation. Consecutive blood samples were drawn every 2 weeks until an ongoing second trimester pregnancy (n = 164) or a miscarriage (n = 39) occurred. After exclusion of women with complicated pregnancies or deliveries (n = 42), 122 women were included. The serum samples collected at <6, 6–8, 8–10, 10–12 and >12 weeks’ gestation were analyzed for 29 common analytes. Subsequently the RIs were calculated according to the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) recommendations (2.5–97.5th percentiles) and compared with the conventional RIs for non-pregnant women. Results Human chorionic gonadotropin (hCG), progesterone (P4), estradiol (E2), pregnancy-associated plasma protein A (PAPP-A), cancer antigen 125 (CA125), thyroid stimulating hormone (TSH), creatinine (CREA) and albumin (ALB) showed an early pregnancy-dependent change compared with conventional limits. For ALB the change was seen at 5.5 weeks’ gestation. Conclusions We report gestational age-specific RIs available from the early part of the first trimester applicable to everyday clinical care of pregnant women. Well-known alterations of RIs seen in later trimesters are also observed in the first.

scholarly journals Age- and sex-specific reference intervals for the serum cystatin C/creatinine ratio in healthy children (0–18 years old)

2019 ◽  
Vol 47 (7) ◽  
pp. 3151-3159 ◽  
Author(s):  
Changjin Liu ◽  
Jing Wen ◽  
Jialin Xiang ◽  
Xuhong Ouyang ◽  
Yan Yang ◽  
...  
Keyword(s):  
Cystatin C ◽  
Pediatric Population ◽  
Age Groups ◽  
Serum Markers ◽  
Reference Intervals ◽  
Specific Reference ◽  
Healthy Children ◽  
Serum Samples ◽  
Serum Cystatin C ◽  
Age And Sex

Objective This study aimed to investigate serum levels of the cystatin C (CysC)/creatinine (Cr) ratio and renal serum markers (CysC, Cr, urea, and uric acid [UA]) for different ages and by sex. We also aimed to establish pediatric reference intervals for the serum CysC/Cr ratio. Methods Serum samples were collected from 4765 healthy children (0–18 years old). Serum markers of renal function were measured, and the CysC/Cr ratio of each participant was calculated and statistically analyzed. Results The renal marker CysC did not substantially change after 1 year old. Cr, urea, and UA levels generally increased with age. However, the serum CysC/Cr ratio steadily decreased with age. The CysC/Cr ratio showed significant differences in age among all age groups and varied with sex, except for in the 1 to 6-year-old groups. The overall serum CysC/Cr ratio in girls was higher than that in boys. Conclusion Reference intervals of the serum CysC/Cr ratio in the pediatric population were established. These intervals need to be partitioned by age and sex.

Serum vitamin K1 concentration and vitamin K-dependent clotting factor activity in maternal and fetal cord blood

1985 ◽  
Vol 153 (7) ◽  
pp. 771-774 ◽  
Author(s):  
Léon Sann ◽  
Michel Leclercq ◽  
Jacques Troncy ◽  
Marc Guillaumond ◽  
Marcel Berland ◽  
...  
Keyword(s):  
Cord Blood ◽  
Vitamin K ◽  
Serum Vitamin ◽  
Clotting Factor ◽  
Vitamin K1 ◽  
Factor Activity ◽  
Fetal Cord Blood

Age-specific reference values improve the diagnostic performance of AMH in polycystic ovary syndrome

2020 ◽  
Vol 58 (8) ◽  
pp. 1291-1301 ◽  
Author(s):  
Osman Evliyaoglu ◽  
Mathias Imöhl ◽  
Ralf Weiskirchen ◽  
Josef van Helden
Keyword(s):  
Polycystic Ovary Syndrome ◽  
Diagnostic Performance ◽  
Polycystic Ovary ◽  
Reproductive Hormones ◽  
Youden Index ◽  
Specific Reference ◽  
Reference Ranges ◽  
Ovary Syndrome ◽  
Significant Difference ◽  
Age Dependent

AbstractBackgroundThe increased secretion of anti-Müllerian hormone (AMH) by the growing follicles has been supposed as a determinative feature of polycystic ovary syndrome (PCOS). The diagnostic performance of AMH in PCOS is superior compared to the free androgen index (FAI) and luteinizing hormone (LH)/follicle-stimulating hormone (FSH) quotient. We established age-dependent reference ranges to further improve the diagnostic performance of AMH.MethodsIn a cross-sectional study, in samples of 4712 reproductive age patients, ranging from 14 to 50 years, BMI, AMH and other reproductive hormones were determined by immunoassay or tandem mass spectrometry (LC-MS/MS) to calculate age-specific reference ranges and the diagnostic performance.ResultsAge-specific diagnostic performances for Elecsys® AMH, FAI and LH/FSH ratio were established in the reference group. No significant difference in BMI was found between the groups. AMH values were significantly negatively correlated with age (r = −0.628, p < 0.001) in patients with normal ovarian function, but there was no correlation between age and AMH levels in PCOS patients (r = − 0.041, p < 0.174). In all the study groups, AMH showed a weak correlation between FAI and LH/FSH ratio (r = 0.302, p < 0.001 and r = 0.434, p < 0.001, respectively). The sensitivity/specificity for AMH, FAI and LH/FSH ratio were 89/96%, 71/69% and 75/72%, respectively, according to the Youden index.ConclusionsWe determined the age-dependent reference ranges for serum AMH levels in a large population-based study and calculated the age-specific diagnostic performance of FAI and LH/FSH ratio, which allows physicians to evaluate patients with PCOS who have normal AMH levels. AMH is suggested as the strongest diagnostic marker in patients with PCOS compared to FAI and LH/FSH ratio.

Immunoglobulin G (IgG) and IgG subclass reference intervals in children, using Optilite® reagents

2018 ◽  
Vol 56 (8) ◽  
pp. 1319-1327 ◽  
Author(s):  
Olivier Grunewald ◽  
Benjamin Lopez ◽  
Séverine Brabant ◽  
Stéphanie Rogeau ◽  
Antoine Deschildre ◽  
...  
Keyword(s):  
Immunoglobulin G ◽  
Age Groups ◽  
Reference Intervals ◽  
Igg Subclasses ◽  
Specific Reference ◽  
Igg Subclass ◽  
Serum Samples ◽  
Gender Specific Differences ◽  
Specific Igg ◽  
Changes Over Time

Abstract Background: Immunoglobulin G (IgG) and IgG subclass assays are indicated in patients with suspected primary immunodeficiency (PID). Commercially available assays for IgG subclass determination are calibrated against various preparations, and so specific reference values are required for each of them. Using Optilite® reagents from The Binding Site Group Ltd., we sought to determine the pediatric IgG and IgG subclass reference intervals with respect to the ERM-DA470k certified reference material. Methods: Levels of IgG and IgG subclasses were analyzed in serum samples collected from a large cohort of PID-free children and adolescents. Reference intervals were calculated for previously published age groups (6–12 months, 12–18 months, 18 months–2 years, 2–3 years, 3–4 years, 4–6 years, 6–9 years, 9–12 years and 12–18 years), according to the Clinical and Laboratory Standards Institute’s C28-A3c protocol. Results: A total of 456 serum samples were analyzed. The correlation between the total IgG and the sum of the IgG subclasses was good (r2=0.96). No statistically significant gender-specific differences were observed. Our results for the changes over time in IgG and IgG subclass levels are consistent with previous reports. The differences between our lower/upper reference limits and those in the literature are probably due to variations in calibration. Conclusions: Our present results provide a reliable basis for the diagnosis of PIDs in childhood and for the accreditation of laboratories using Optilite® immunoturbidimetric reagents for IgG subclass measurement. Laboratory scientists and clinicians should be aware of the need for manufacturer-specific IgG subclass reference intervals.

scholarly journals Pediatric Population Reference Value Distributions for Cancer Biomarkers and Covariate-Stratified Reference Intervals in the CALIPER Cohort

2014 ◽  
Vol 60 (12) ◽  
pp. 1532-1542 ◽  
Author(s):  
Victoria Bevilacqua ◽  
Man Khun Chan ◽  
Yunqi Chen ◽  
David Armbruster ◽  
Beth Schodin ◽  
...  
Keyword(s):  
Cancer Progression ◽  
Pediatric Population ◽  
Specific Antigen ◽  
Reference Value ◽  
Cancer Biomarkers ◽  
Reference Intervals ◽  
Specific Reference ◽  
Cancer Antigen 125 ◽  
Serum Samples ◽  
Free Psa

Abstract BACKGROUND Cancer biomarkers are commonly used in pediatrics to monitor cancer progression, recurrence, and prognosis, but pediatric reference value distributions have not been well established for these markers. The Canadian Laboratory Initiative on Pediatric Reference Intervals (CALIPER) sought to develop a pediatric database of covariate-stratified reference value distributions for 11 key circulating tumor markers, including those used in assessment of patients with childhood or adult cancers. METHODS Healthy community children from birth to 18 years of age were recruited to participate in the CALIPER project with informed parental consent. We analyzed serum samples from 400–700 children (depending on the analyte in question) on the Abbott Architect ci4100 and established reference intervals for α-fetoprotein (AFP), antithyroglobulin (anti-Tg), human epididymis protein 4 (HE4), cancer antigen 125 (CA125), CA15-3, CA19-9, progastrin-releasing peptide (proGRP), carcinoembryonic antigen (CEA), squamous cell carcinoma antigen (SCC), and total and free prostate specific antigen (PSA) according to CLSI C28-A3 statistical guidelines. RESULTS We observed significant fluctuations in biomarker concentrations by age and/or sex in 10 of 11 biomarkers investigated. Age partitioning was required for CA153, CA125, CA19-9, CEA, SCC, proGRP, total and free PSA, HE4, and AFP, whereas sex partitioning was also required for CA125, CA19-9, and total and free PSA. CONCLUSIONS This CALIPER study established a database of childhood reference intervals for 11 tumor biomarkers and revealed dramatic fluctuations in tumor marker concentrations between boys and girls and throughout childhood. In addition, important differences between the adult and pediatric population were observed, further highlighting the need for pediatric-specific reference intervals.

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