Objective: To compare pregnancy-associated plasma protein-A (PAPP-A) levels in individuals with and without coronary artery disease (CAD).
Study design: Cross-sectional comparative study.
Place and duration of study: Department of Chemical Pathology and Endocrinology, Armed Forces Institute of Pathology (AFIP), Rawalpindi, in collaboration with Armed Forces Institute of Cardiology (AFIC), from September 2008 to March 2010.
Methodology: One hundred and twenty five (125) individuals both male and female were included in the study. Blood for PAPP-A and lipid profile was collected, just before angiography. On the basis of angiography, the individuals were divided into those with and without CAD. PAPP-A was analyzed by using Diagnostic System Laboratories (DSL) Enzyme Linked Immunosorbent Assay (ELISA) kit and reading was taken by ELISA reader. Lipid profile was determined on automated analyzers Selectra-2 and Vitros 5.1.
Results: Amongst the 125 individuals, 41 individuals were without CAD whereas 84 individuals were having CAD. Mean PAPP-A levels were 0.74 ± 0.35 mIU/L in those without CAD whereas mean PAPP-A levels in those with CAD were 1.35 ± 0.57 mIU/L. The difference between the two groups was statistically significant (p < 0.001). A PAPP-A cut off level of 0.85 mIU/L had a sensitivity and specificity of 78% and 70% respectively for diagnosing atherosclerotic CAD.
Conclusion: PAPP-A is a potentially relevant marker of the presence and extent of coronary atherosclerosis as its levels are elevated in CAD as compared to individuals without CAD.