TY - JOUR
T1 - Measurements of 25-hydroxyvitamin D concentrations in archived dried blood spots are reliable and accurately reflect those in plasma
AU - Heath, Alicia K
AU - Williamson, Elizabeth Jane
AU - Ebeling, Peter Robert
AU - Kvaskoff, David
AU - Eyles, Darryl W
AU - English, Dallas R
PY - 2014
Y1 - 2014
N2 - Context: Recognition that vitamin D might be associated with many chronic diseases has led to large-scale epidemiological and clinical studies. Dried blood spots (DBS) are a useful resource for these studies. Consequently, accurate, efficient, and inexpensive assays to quantify 25-hydroxyvitamin D (25OHD) in DBS are required. Copyright
Objective: This study evaluated the validityandreliability of a liquid chromatography-tandem mass spectrometry assay for measuring 25OHD in archived DBS and compared measurements of 25OHD in DBS with those in plasma.
Design and Participants: Sixty-two participants in the Melbourne Collaborative Cohort Study who had plasma and matching DBS stored since study entry in the early 1990s were randomly selected for a study calibrating 25OHD concentrations in DBS with plasma. As part of a study of vitamin D and mortality, cancer, and diabetes, we also assessed the reliability of measurements from DBS using 500 replicates placed randomly within 31 batches run over 15 months.
Outcome Measure: 25OHD concentrations were measured by liquid chromatography-tandem mass spectrometry.
Results: There was good agreement between measurements of 25OHD from DBS and plasma; R2= 0.73 from a regression of plasma concentration on DBS concentration. The within-batch and between- batch intraclass correlations from the 500 replicate measurements were 0.82 (95 confidence interval, 0.80, 0.85) and 0.73 (95 confidence interval, 0.68, 0.78), respectively.
Conclusions: Measuring 25OHD in DBS is a valid and reliable alternative to measuring 25OHD in sera or plasma. A simple calibration model was developed to convert measurements from DBS to equivalent plasma measurements, thus enabling comparisons against clinical reference ranges and with studies using sera or plasma samples.
AB - Context: Recognition that vitamin D might be associated with many chronic diseases has led to large-scale epidemiological and clinical studies. Dried blood spots (DBS) are a useful resource for these studies. Consequently, accurate, efficient, and inexpensive assays to quantify 25-hydroxyvitamin D (25OHD) in DBS are required. Copyright
Objective: This study evaluated the validityandreliability of a liquid chromatography-tandem mass spectrometry assay for measuring 25OHD in archived DBS and compared measurements of 25OHD in DBS with those in plasma.
Design and Participants: Sixty-two participants in the Melbourne Collaborative Cohort Study who had plasma and matching DBS stored since study entry in the early 1990s were randomly selected for a study calibrating 25OHD concentrations in DBS with plasma. As part of a study of vitamin D and mortality, cancer, and diabetes, we also assessed the reliability of measurements from DBS using 500 replicates placed randomly within 31 batches run over 15 months.
Outcome Measure: 25OHD concentrations were measured by liquid chromatography-tandem mass spectrometry.
Results: There was good agreement between measurements of 25OHD from DBS and plasma; R2= 0.73 from a regression of plasma concentration on DBS concentration. The within-batch and between- batch intraclass correlations from the 500 replicate measurements were 0.82 (95 confidence interval, 0.80, 0.85) and 0.73 (95 confidence interval, 0.68, 0.78), respectively.
Conclusions: Measuring 25OHD in DBS is a valid and reliable alternative to measuring 25OHD in sera or plasma. A simple calibration model was developed to convert measurements from DBS to equivalent plasma measurements, thus enabling comparisons against clinical reference ranges and with studies using sera or plasma samples.
UR - http://press.endocrine.org.ezproxy.lib.monash.edu.au/doi/pdf/10.1210/jc.2014-1269
U2 - 10.1210/jc.2014-1269
DO - 10.1210/jc.2014-1269
M3 - Article
SN - 0021-972X
VL - 99
SP - 3319
EP - 3324
JO - The Journal of Clinical Endocrinology & Metabolism
JF - The Journal of Clinical Endocrinology & Metabolism
IS - 9
ER -