The atherogenic index of plasma is increased by hormonal contraception.

BACKGROUND/AIMS: Oral contraceptives are known to induce secondary dyslipidemia. The aim of this study was to determine if hormonal contraceptives affect the new atherogenic index of plasma (AIP) = log[triglycerides (TG)/high-density lipoprotein cholesterol (HDL-C)] together with the total cholesterol/HDL-C (TC/HDL-C) and the apolipoprotein B/apolipoprotein A1 (apoB/apoA1) ratios.

DESIGN AND

METHODS

This study included 43 healthy women. Blood lipids, apoA1, apoB and the high-sensitivity C-reactive protein (hsCRP) concentration were examined before the start of hormonal contraception and after 3, 6 and 9 months of its regular use. AIP, the apoB/apoA1 ratio and the TC/HDL-C ratio were calculated.

RESULTS

After 9 months of continued hormonal contraception, we found significantly increased levels of TC, HDL-C, low-density lipoprotein cholesterol (LDL-C), TG, apoA1 and apoB (p < 0.05 for all analytes). The TC/HDL-C and apoB/apoA1 ratios remained unchanged; however, the AIP and the hsCRP concentration increased significantly (p < 0.005 and p < 0.006). LDL-C increased slightly over the first three examinations (0, 3, 6 months), and the rest of the indices increased over the first two examinations (0, 3 months) and maintained stable values through the fourth examination (9 months).

CONCLUSIONS

The increased AIP and hs-CRP concentration after 9 months of hormonal contraception demonstrate that contraceptive-induced dyslipidemia has a proatherogenic nature, even when the TC/HDL-C and the apoB/apoA1 ratios are unchanged.