title: Prevalence of vitamin D deficiency and consequences for PTH reference values.
abstract: Reference values of PTH depend on vitamin D status of the reference population. This is often not described in package inserts. The aim of the present study was therefore to calculate assay specific PTH reference levels in EDTA plasma for the Architect (Abbott) in relation to 25-hydroxyvitamin D (25OHD) levels. The relation between PTH levels, 25OHD, BMI, age, gender and kidney function was determined in a cohort of older individuals from the Longitudinal Aging Study Amsterdam (LASA, n = 738, age 55-65 years) and in a cohort of healthy individuals from the Netherlands Study of Depression and Anxiety (NESDA, n = 633, 18-65 years). The LASA cohort is a representative sample of the Dutch older population. As expected, PTH reference values were significantly lower in 25OHD sufficient subjects (25OHD>50 nmol/L) than in 25OHD deficient and insufficient subjects. The 97.5th percentile of PTH in 25OHD sufficient subjects was 10 pmol/L (94.3 pg/mL), which was higher than the upper limit stated by the manufacturer (7.2 pmol/L or 68.3 pg/mL). The relation between vitamin D and PTH was independent of age, gender, BMI and kidney function. In conclusion, we have shown that it is important to establish PTH reference values in a local reference population taking 25OHD status into account.
authors.affiliation: Dept. Clinical Chemistry Saint Lucas Andreas Hospital, Amsterdam, The Netherlands. Electronic address: m.deckers@slaz.nl.
authors.forename: M M L
authors.initials: MM
authors.lastname: Deckers
authors.forename: R T
authors.initials: RT
authors.lastname: de Jongh
authors.forename: P T A M
authors.initials: PT
authors.lastname: Lips
authors.forename: B W J H
authors.initials: BW
authors.lastname: Penninx
authors.forename: Y
authors.initials: Y
authors.lastname: Milaneschi
authors.forename: J H
authors.initials: JH
authors.lastname: Smit
authors.forename: N M
authors.initials: NM
authors.lastname: van Schoor
authors.forename: M A
authors.initials: MA
authors.lastname: Blankenstein
authors.forename: A C
authors.initials: AC
authors.lastname: Heijboer
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010281:Parathyroid Hormone / Q000097:blood*; D015995:Prevalence; D012016:Reference Values; D014808:Vitamin D Deficiency / Q000097:blood* / Q000453:epidemiology*; D055815:Young Adult
chemical_list: D010281:Parathyroid Hormone
keywords: 25-hydroxyvitamin D; 25OHD; BMI; CKD; CKD-MBD; Chronic Kidney Disease; Chronic Kidney Disease Mineral and Bone Disorder; GFR; Glomerular filtration rate; KDIGO; KDOQI; Kidney Disease: Improving Global Outcomes; LASA; Longitudinal Aging Study Amsterdam; NESDA; National Kidney Foundation-Kidney Disease Outcomes Quality Initiative; Netherlands Study of Depression and Anxiety; PTH; Reference value; Vitamin D; body mass index; parathyroid hormone