Comparison of dried blood spot to venous methods for hemoglobin A1c, glucose, total cholesterol, high-density lipoprotein cholesterol, and C-reactive protein

• Dried blood spots (DBS) can be collected by non-phlebotomists.
• DBS methods require less space and are more easily transported than venous assays.
• DBS methods need to be validated against venous methods and require small volumes.
• DBS compared well to venous methods for hemoglobin A1c, glucose and C-reactive protein.
• DBS did not compare well to venous methods for total and high-density lipoprotein cholesterol.

BackgroundCompared to venipuncture, dried blood spots (DBS) can be collected by non-phlebotomists in non-clinical settings, is relatively inexpensive, more easily transported and stored conveniently. Disadvantages of DBS include difficult assay development and validation. This study compared DBS to venous methods for hemoglobin A1c, glucose, total cholesterol, high-density lipoprotein cholesterol, and C-reactive protein (CRP).MethodsDBS collection and venipuncture were performed on 401 participants. The DBS were collected on Whatman 903 protein saver card. For analysis, 3.2 mm blood punches were placed into a 96-well microtiter plate for elution and then analyzed.ResultsThe Pearson squared correlation coefficients were high for hemoglobin A1c (0.92), CRP (0.84) and glucose (0.81) and low for total cholesterol (0.34) and high-density lipoprotein (HDL) cholesterol (0.30). Sensitivity (> 82%) and specificity (> 90%) were high for CRP, glucose and hemoglobin A1c at selected clinical cut-points. Low sensitivity (< 41%) and high specificity (> 87%) were seen for total and HDL cholesterol.ConclusionsThe hemoglobin A1c, glucose and CRP correlated well between DBS and venous methods (r2 > 0.80), but there was a poor correlation for total and HDL cholesterol (r2 < 0.34). This resulted in low sensitivity of DBS methods for total and HDL cholesterol.