Varying Definitions of Carotid Intima-Media Thickness and Future Cardiovascular Disease: A Systematic Review and Meta-Analysis

BACKGROUND

Carotid intima-media thickness (cIMT) has been widely used as a predictor of future cardiovascular disease (CVD); however, various definitions of cIMT exist. This study provides a systematic review and meta-analysis of the associations between different cIMT definitions and CVD.

METHODS AND RESULTS

A systematic review of the different cIMT definitions used in prospective cohort studies was performed. The relationships between cIMT of different definitions (common carotid artery IMT [CCA-IMT], internal carotid artery IMT [ICA-IMT], combined segments [combined-IMT], mean CCA-IMT, and maximum CCA-IMT) with future stroke, myocardial infarction (MI), and CVD events were analyzed using random effects models. Among 2287 articles, 18 articles (14 studies) with >10 different cIMT definitions were identified and included in our meta-analysis. After adjusting for age and sex, a 1-SD increase in CCA-IMT was associated with future stroke (hazard ratio [HR], 1.32 [95% CI, 1.27-1.38]), MI (HR, 1.27 [95% CI, 1.22-1.33]), and CVD events (HR, 1.28 [95% CI, 1.19-1.37]). A 1-SD increase in ICA-IMT was related to future stroke (HR, 1.25 [95% CI, 1.11-1.42]) and CVD events (HR, 1.25 [95% CI, 1.04-1.50]) but not MI (HR, 1.26 [95% CI, 0.98-1.61]). A 1-SD increase in combined-IMT was associated with future stroke (HR, 1.30 [95% CI, 1.08-1.57]) and CVD events (HR, 1.36 [95% CI, 1.23-1.49]). Maximum CCA-IMT was more strongly related than mean CCA-IMT with risk of MI, and both measures were similarly associated with stroke and CVD events.

CONCLUSIONS

Combined-IMT is more strongly associated with CVD events compared with single-segment cIMT definitions. Maximum CCA-IMT shows a stronger association with MI than mean CCA-IMT. Further research is warranted to validate our findings and to standardize the cIMT measurement protocol, as well as to explore underlying mechanisms.

Early Midlife Cardiovascular Health Influences Future HDL Metrics in Women: The SWAN HDL Study

Background Utility of high-density lipoprotein cholesterol (HDL-C) in assessing the antiatherogenic properties of HDL may be limited in midlife women. Novel metrics of HDL function, lipid contents, and subclasses may better reflect the atheroprotective capacities of HDL, supporting the need to evaluate how cardiovascular health affects these metrics in women. We assessed the relationship of early midlife Life's Simple 7 (LS7) score and its health behavior components with future HDL function (HDL-cholesterol efflux capacity), HDL-phospholipid, HDL-triglyceride, HDL particles (HDL-P) and size, and the relationship between LS7 score and changes in HDL metrics over time. Methods and Results We analyzed 529 women (baseline age: 46.4 [2.6] years, 57% White) from the SWAN HDL (Study of Women's Health Across the Nation HDL) study who had baseline LS7 followed by future repeated HDL metrics. Multivariable linear mixed models were used. Higher LS7 score was associated with favorable future HDL profile (higher HDL-phospholipid, total HDL-P and large HDL-P, lower HDL-triglyceride, and larger overall HDL size). Ideal body mass index was associated with higher HDL-cholesterol efflux capacity, HDL-phospholipid, and large HDL-P, lower HDL-triglyceride and small HDL-P, and larger overall HDL size. Ideal physical activity was associated with higher HDL-phospholipid, and total, large, and medium HDL-P. Ideal smoking was associated with less HDL-triglycerides. Diet was not related to HDL metrics. Higher LS7 score and ideal body mass index were associated with slower progression of HDL size over time. Conclusions Novel HDL metrics may better reflect the clinical utility of HDL. Improving lifestyle at midlife, particularly maintaining ideal body mass index, is associated with better future HDL phenotype.

Childhood Maltreatment and Arterial Stiffness Among Midlife Women

Background Childhood maltreatment has been associated with arterial stiffness. This relationship has not been examined specifically among women at midlife, a time of increased arterial stiffness in women. This study tested whether childhood maltreatment is associated with arterial stiffness among a cohort of midlife women. Methods and Results A total of 162 nonsmoking perimenopausal and postmenopausal women free of clinical cardiovascular disease (mean age, 54 years; 72% White race, 23% Black race, and 5% Asian/Pacific Islander or Mixed race) completed the Child Trauma Questionnaire at baseline. At a follow-up visit 5 years later, blood pressure and carotid-femoral pulse wave velocity (a measure of arterial stiffness) were assessed. Relationships between childhood maltreatment and carotid-femoral pulse wave velocity were tested in linear regression models, adjusting for time between visits, age, race and ethnicity, education, body mass index, heart rate, hypertension medication, and diastolic blood pressure. Seventy-one women (44% of the sample) met criteria for a history of childhood maltreatment. Women with a history of childhood maltreatment had higher carotid-femoral pulse wave velocity (B [SE]=0.47 [0.21]; P=0.03) than women without this history, controlling for time between visits, age, race and ethnicity, education, body mass index, heart rate, hypertension medication, and diastolic blood pressure. Conclusions Among these midlife women, childhood maltreatment was associated with arterial stiffness, highlighting the potential long-term cardiovascular implications of childhood maltreatment.

Age at Menopause in Relationship to Lipid Changes and Subclinical Carotid Disease Across 20 Years: Study of Women's Health Across the Nation

Background Younger age at final menstrual period (FMP) is associated with increased risk for cardiovascular disease events. This paper evaluated whether older age at FMP is associated with more favorable patterns of lipid changes during the menopause transition and whether these changes are associated with less subclinical carotid disease in the postmenopausal years. Methods and Results Lipids and lipoproteins were measured repeatedly among 1554 premenopausal women who had a natural menopause during follow-up years (median=18.8 years); a subset of 890 women also had measures of carotid intima media thickness, adventitial diameter, and plaque. Women who had an older FMP age had less adverse changes in cholesterol from 1 to 3 years after FMP, and in triglycerides from FMP to 3 years after FMP, but they had more adverse changes in ApoB and Apo A1 from 3 years before to 1 year after the FMP. Increasing cholesterol and ApoB from 1 to 3 years after FMP were associated with greater intima media thickness and adventitial diameter, and the greater likelihood of a plaque score >2 the older the age at FMP. Conclusions Despite the epidemiological literature showing early age at FMP is associated with elevated risk for cardiovascular disease events, older age at FMP had inconsistent associations with less adverse lipid changes in midlife, which did not translate into less risk for subclinical carotid disease and in some cases more risk. These findings are restricted to women who experience FMP in the normative age range for the menopausal transition.