Correlation between Serum Sialic Acid, Serum Lipids, Cardiac Troponin I and Myoglobin among Women on Combined Oral Contraceptives

Background: Women using combined oral contraceptives have an increased risk of developing cardiovascular disease. While the utility of biomarkers such as serum lipids have been well evaluated, serum sialic acid, which has shown some promise as a marker of cardiovascular disease progression has been poorly studied. This study aimed to determine the correlation between sialic acid and lipid profile as risk factors of cardiovascular disease in women on combined oral contraceptives. Materials and Methods: This was a cross-sectional study involving 143 women on combined oral contraceptive pill as the study group and 100 age and sex matched healthy controls. Serum levels of Total Sialic Acid (TSA), lipids, and some cardiac biomarkers (Myoglobin, Creatine Kinase-MB and Troponin-I) were measured, summarized as mean (±SD) and compared. Correlation between serum level of sialic acid and each of the measured serum lipid component was subsequently determined using correlation analysis. Results: Sialic acid (1.070±0.117 vs 0.837±0.272), Total cholesterol (3.944±0.918 vs 3.106±0.635), Low density lipoprotein cholesterol (2.408±1.085 vs 1.088±0.392), High density lipoprotein cholesterol (1.049±0.421 vs 0.902±0.542) & Triglycerides (1.620±0.703 vs 1.052±0.514) were all significantly (P<0.05) higher in the combined oral contraceptive group than controls respectively. Sialic acid demonstrated a weak but positive correlation with Myoglobin (r= +0.403), Creatine kinase-MB (r= +0.441) and Troponin-I (r= +0.424). While TGs and sialic acid were shown to have a very weakly positive association (r= +0.089), TC, LDL-C, and HDL-C all had very weakly negative correlations (r= -0.136, -0.146, and -0.006, respectively). Conclusion: Combined oral contraceptives use confers an artherogenic lipid profile imparting a positive cardiovascular disease risk. Although sialic acid is significantly higher among combined oral contraceptive users and shows a positive relationship with cardiac biomarkers, it correlates poorly with serum lipids suggesting its limited utility as a CVD marker.