OBJECTIVE: The aim of this study was to investigate the seasonal and age-related variation of vitamin D and PTH serum concentrations in a large general patient population in Western Norway. DESIGN: A retrospective study was conducted at the Hormone laboratory, Haukeland University Hospital, Bergen, Norway. All analyses of 25-hydroxyvitamin D (25(OH)D) (n = 8325), 1,25-dihydroxyvitamin D (1,25(OH)2D) (n = 4509) and PTH (n = 4203) requested from private practitioners from 2005 to 2008 were included. All three analytes were available in 1551 subjects. Subjects. Mean age of the study population was 49.8 years and 70.9% of the samples were from women. RESULTS: The highest concentrations of 25(OH)D and 1,25(OH)2D were observed in July-September. In April 43% of the studied population had 25(OH)D concentrations below 50 nmol/L. There was a positive correlation between 25(OH)D and 1,25(OH)2D (p < 0.001). The levels of 25(OH)D and PTH were negatively correlated (p < 0.001) while 1,25(OH)2D and PTH showed a weak positive correlation (p = 0.015). We observed higher concentrations of 25(OH)D (p = 0.003) and lower 1,25(OH)2D levels (p < 0.001) in the older age groups. PTH increased throughout the whole age span (p < 0.001). CONCLUSION: We observed a seasonal variation in 25(OH)D and 1,25(OH)2D with low serum concentrations during winter/early spring while PTH showed an inverse pattern. Higher levels of PTH in winter and the elderly may reflect an impaired vitamin D status that may affect calcium homeostasis and bone health.
OBJECTIVE: The aim of this study was to investigate the seasonal and age-related variation of vitamin D and PTH serum concentrations in a large general patient population in Western Norway. DESIGN: A retrospective study was conducted at the Hormone laboratory, Haukeland University Hospital, Bergen, Norway. All analyses of 25-hydroxyvitamin D (25(OH)D) (n = 8325), 1,25-dihydroxyvitamin D (1,25(OH)2D) (n = 4509) and PTH (n = 4203) requested from private practitioners from 2005 to 2008 were included. All three analytes were available in 1551 subjects. Subjects. Mean age of the study population was 49.8 years and 70.9% of the samples were from women. RESULTS: The highest concentrations of 25(OH)D and 1,25(OH)2D were observed in July-September. In April 43% of the studied population had 25(OH)D concentrations below 50 nmol/L. There was a positive correlation between 25(OH)D and 1,25(OH)2D (p < 0.001). The levels of 25(OH)D and PTH were negatively correlated (p < 0.001) while 1,25(OH)2D and PTH showed a weak positive correlation (p = 0.015). We observed higher concentrations of 25(OH)D (p = 0.003) and lower 1,25(OH)2D levels (p < 0.001) in the older age groups. PTH increased throughout the whole age span (p < 0.001). CONCLUSION: We observed a seasonal variation in 25(OH)D and 1,25(OH)2D with low serum concentrations during winter/early spring while PTH showed an inverse pattern. Higher levels of PTH in winter and the elderly may reflect an impaired vitamin D status that may affect calcium homeostasis and bone health.
Authors: Victoria Zigmont; Amy Garrett; Jin Peng; Michal Seweryn; Grzegorz A Rempala; Randall Harris; Christopher Holloman; Thomas E Gundersen; Anders Ahlbom; Maria Feychting; Tom Borge Johannesen; Tom Kristian Grimsrud; Judith Schwartzbaum Journal: Nutr Cancer Date: 2015-08-28 Impact factor: 2.900
Authors: M Kox; M J W van den Berg; J G van der Hoeven; J P M Wielders; A J van der Ven; P Pickkers Journal: Clin Exp Immunol Date: 2013-02 Impact factor: 4.330
Authors: Amie L Peterson; Charles Murchison; Cyrus Zabetian; James B Leverenz; G Stennis Watson; Thomas Montine; Natasha Carney; Gene L Bowman; Karen Edwards; Joseph F Quinn Journal: J Parkinsons Dis Date: 2013 Impact factor: 5.568
Authors: A L Darling; K H Hart; M A Gibbs; F Gossiel; T Kantermann; K Horton; S Johnsen; J L Berry; D J Skene; R Eastell; R Vieth; S A Lanham-New Journal: Osteoporos Int Date: 2013-08-28 Impact factor: 4.507