Contraceptives and cerebral thrombosis: a five-year national case-control study

Area of Science:

• Neurology
• Cardiovascular Research
• Pharmacology

Background:

• Cerebral thromboembolic attacks (CTA), including thrombotic stroke and transient ischemic attacks, pose significant health risks.
• The influence of oral contraceptives (OCs) on CTA risk requires thorough investigation due to widespread use.

Purpose of the Study:

• To assess the association between oral contraceptive use and the risk of cerebral thromboembolic attacks (CTA).
• To evaluate the impact of different estrogen doses and progestin generations in OCs on CTA risk.

Main Methods:

• A 5-year case-control study conducted in Danish hospitals.
• Inclusion of women aged 15-44 with a first-ever CTA, with controls matched by age.
• Multivariate analysis adjusting for confounders like smoking, hypertension, and OC use duration.

Main Results:

• Current OC users had an increased risk of CTA, with risk decreasing significantly as estrogen dose lowered.
• OCs with 50 microg ethinyl estradiol (EE) showed an odds ratio (OR) of 4.5, while 20 microg EE had an OR of 1.7.
• Second-generation progestin OCs (20-30 microg EE) had an OR of 2.2, compared to 1.4 for third-generation progestins, with a risk ratio of 0.6 after dose correction.

Conclusions:

• High-dose oral contraceptives and those with second-generation progestins are linked to an elevated risk of CTA.
• A 2.5-fold increase in CTA risk was observed with increasing estrogen dose from 20 to 50 microg EE.
• Low-dose OCs with second-generation progestins presented a 61% higher CTA risk compared to third-generation progestin users.