Female-specific risk factors of parity and menopause age and risk of carotid plaque: the multi-ethnic study of atherosclerosis

Background: Female-specific factors of grand multiparity (≥5 births) and early menopause age are associated with an increased risk of cardiovascular disease (CVD). However, mechanisms are incompletely understood. Carotid plaque is a marker of subclinical atherosclerosis and associated with increased CVD risk. We evaluated the association of female-specific factors with plaque burden.

Methods: We included 2,313 postmenopausal women in the Multi-Ethnic Study of Atherosclerosis, free of clinical CVD, whose parity and menopause age were ascertained by questionnaires and carotid plaque measured by ultrasound at baseline and 10 years later. Parity was categorized as nulliparity (reference), 1-2, 3-4 and ≥5 live births. Menopause age was categorized as <45, 45-49, 50-54 (reference) and ≥55 years. Multivariable regression was performed to evaluate the association of parity and menopause age with carotid plaque presence (yes/no) and extent [carotid plaque score (CPS)].

Results: The mean age was 64±9 years; 52.3% had prevalent carotid plaque at baseline. Compared to nulliparity, grand multiparity was significantly associated with prevalent carotid plaque after adjustment for CVD risk factors (prevalence ratio 1.17 (95% CI 1.03-1.35)) and progression of CPS over 10 years [percent difference 13% (95% CI 3-23)]. There was not any significant association of menopause age with carotid plaque presence or progression in fully-adjusted models.

Conclusion: In a multiethnic cohort, grand multiparity was independently associated with carotid plaque presence and progression. Early menopause, a known risk factor for CVD, was not captured by carotid plaque in this study. These findings may have implications for refining CVD risk assessment in women.