Age-Specific Sex Differences in Magnetic Resonance Imaging-Depicted Carotid Intraplaque Hemorrhage
Navneet Singh1, Alan R Moody2, Bowen Zhang1
1From the Department of Medical Imaging, Faculty of Medicine (N.S., A.R.M., B.Z., I.K., S.C., P.N.T.) and Department of Statistical Sciences (P.N.T.), University of Toronto, Ontario, Canada; and Department of Neurology, Boston Children's Hospital, Harvard Medical School, MA (K.K.).
Insights
Men have significantly higher odds of carotid intraplaque hemorrhage (IPH) compared to women across all age groups. This difference in IPH, an unstable plaque component, may contribute to higher stroke rates in men.
Area of Science:
- Cardiovascular Imaging
- Cerebrovascular Disease Research
- Atherosclerosis Studies
Background:
- Stroke incidence is higher in men than women, particularly between the 40s and 70s.
- Carotid intraplaque hemorrhage (IPH) is an unstable atherosclerotic plaque feature linked to stroke risk.
Purpose of the Study:
- To investigate age-specific sex differences in the prevalence of carotid intraplaque hemorrhage (IPH).
- To explore the association between male sex, age, and the presence of carotid IPH.
Main Methods:
- A cross-sectional study analyzed magnetic resonance imaging (MRI) data from 906 patients with low-grade carotid stenosis.
- Carotid IPH was assessed between 2005 and 2014.
- Multivariable logistic regression was used to determine the odds of IPH based on sex and age.
Main Results:
- Overall, 6.95% of patients had carotid IPH, with significantly higher prevalence in men (11.43%) than women (3.09%).
- Men consistently had greater odds of carotid IPH across all age brackets (45-54, 55-64, 65-74, and ≥75 years).
- Male sex was found to modify the effect of age on the presence of carotid IPH (P=0.0411).
Conclusions:
- Men exhibit higher age-specific odds of developing carotid IPH compared to women.
- The odds of carotid IPH in women approach those of men after menopause, suggesting a delayed onset.
- This delayed onset of IPH in women may partially explain sex-based differences in stroke rates, warranting further investigation.
Background And Purpose:
Stroke rates are higher in men compared with women in the fourth through seventh decades of life, and higher rates may result from differences in carotid intraplaque hemorrhage (IPH), an unstable atherosclerotic plaque component. We report age-specific sex differences in the presence of magnetic resonance imaging-depicted carotid IPH.
Methods:
Patients (n=1115) underwent magnetic resonance imaging for carotid IPH between 2005 and 2014. Low-grade carotid stenosis patients (n=906) without prior endarterectomy were eligible for this cross-sectional study.
Results:
Of the 906 patients included (mean age±SD in years, 66.98±15.15), 63 (6.95%) had carotid IPH. In men and women, carotid IPH was present in 11.43% (48 of 420) and 3.09% (15 of 486), respectively (P<0.0001). Multivariable logistic regression analysis confirmed greater odds of carotid IPH in men for all ages: 45 to 54 (odds ratio=45.45; 95% confidence interval, 3.43-500), 55 to 64 years (odds ratio=21.74; 95% confidence interval, 3.21-142.86), 65 to 74 years (odds ratio=10.42; 95% confidence interval, 2.91-37.04), and ≥75 years (odds ratio=5.00; 95% confidence interval, 2.31-10.75). Male sex modified the effect of age on the presence of carotid IPH (β=0.074; SE=0.036; P=0.0411).
Conclusions:
Men have greater age-specific odds of magnetic resonance imaging-depicted carotid IPH compared with women. With increasing age post-menopause, the odds of carotid IPH in women becomes closer to that of men. Delayed onset of carotid IPH in women, an unstable plaque component, may partly explain differential stroke rates between sexes, and further studies are warranted.
