TY - JOUR T1 - Indoor, outdoor, and night work and blood concentrations of vitamin D and parathyroid hormone JO - Scandinavian Journal of Work, Environment & Health PY - 2018/11VL - 44 IS - 6 SP - 647 EP - 657 AU - Daugaard, Stine AU - Garde, Anne Helene AU - Hansen, Åse Marie AU - Vistisen, Helene Tilma AU - Rejnmark, Lars AU - Kolstad, Henrik Albert M3 - doi: 10.5271/sjweh.3745 UR - https://www.sjweh.fi/show_abstract.php?abstract_id=3745 KW - blood concentration KW - cross-sectional study KW - diet KW - indoor work KW - night work KW - occupation KW - occupational health KW - outdoor work KW - parathyroid hormone KW - risk factor KW - season KW - shift work KW - ultraviolet radiation KW - vitamin D N2 - '

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OBJECTIVES ': 'The aim of this study was to examine blood concentrations of 25-hydroxyvitamin D (25OHD) and parathyroid hormone (PTH) among indoor, outdoor, permanent and rotating night workers and the association with hours spent outdoors on and off work days.

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METHODS ': 'Blood samples were collected from 425 workers (162 indoor, 112 outdoor, 118 rotating night and 33 permanent night workers) throughout all seasons. Serum concentrations of 25-hydroxyvitamin D (25OHD) and parathyroid hormone (PTH) were analyzed by isotope dilution liquid chromatography-tandem mass spectrometry (LC MS/MS) and an automated immune analyzer, respectively. Personal light exposure levels were continuously recorded and used to estimate hours spent outdoors (all workers).

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RESULTS ': 'Permanent night workers had 25.3% (95% CI 11.9–36.6) lower 25OHD concentration, 4.55 (95% CI 1.39–14.94) higher odds of vitamin D insufficiency (<50 nmol/L) and 14.5% [95% confidence interval (CI) 0.1–31.1] higher PTH concentration than indoor workers. Outdoor workers had similar 25OHD concentrations but 7.5% (95% CI -0.5–14.9) lower PTH concentration compared to indoor workers. Rotating night workers 25OHD and PTH concentrations did not differ from indoor workers. Concentration of 25OHD increased by 5.2% (95% CI 1.1–9.5) per hour spent outdoor at workdays in the summer.

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CONCLUSION ': 'Clinicians should be aware that vitamin D insufficiency may be more prevalent among permanent night workers and human resources should consider the positive effect of allowing workers to spend time outdoor during work hours.

SN - 0355-3140 ER -