Predictors of subclinical atherosclerosis and microalbuminuria in middle-aged women: a cross-sectional study

BACKGROUND

Cardiovascular disease is of increasing concern in women. The aim was to assess the role of clinical and anthropometric measures in the development of subclinical atherosclerosis.

METHODS

A cross-sectional study in 203 Europid females to determine the prevalence of abnormal carotid intima-media thickness (CIMT) and associated clinical parameters.

RESULTS

The study population had a mean age of the 38.3±5.4 years, a median Body Mass Index of 29.25 (IQR 25.06-36.11) kg/m2 and median waist index (WI) of 1.15 (IQR 1.06-1.34). Increased CIMT was present in 169 (83.25%) participants. Linear regression analysis revealed WI to be the sole predictor of increased CIMT (β=24.387, P<0.001). Post-hoc ROC analysis revealed a WI of 1.12 has 62% sensitivity and 53% specificity for predicting increased CIMT (AUC 0.63, 95% CI 0.55-0.72, P=0.016). The median urinary albumin-creatinine ratio (ACR) was 4.4 mg/g, and the prevalence of microalbuminuria was 8.9%; serum triglycerides were the only independent predictor of ACR.

CONCLUSIONS

Atherosclerosis, as detected by abnormal CIMT, is very prevalent in middle-aged women. Waist index is the major predictor of subclinical atherosclerosis in a contemporary premenopausal female population. A WI of 1.12 exhibits relatively good sensitivity and specificity in predicting the presence of atherosclerosis in this patient population.

Left ventricular hypertrophy contributes to Myocardial Ischemia in Non-obstructive Coronary Artery Disease (the MicroCAD study)

BACKGROUND

The underlying mechanisms causing myocardial ischemia in non-obstructive coronary artery disease (CAD) are still unclear. We explored whether left ventricular hypertrophy (LVH) was associated with myocardial ischemia in patients with stable angina and non-obstructive CAD.

METHODS

132 patients (mean age 63 ± 8 years, 56% women) with stable angina and non-obstructive CAD diagnosed as <50% stenosis by coronary computed tomography angiography (CCTA) underwent myocardial contrast stress echocardiography. Left ventricular (LV) hypertrophy (LVH) was identified by LV mass index >46.7 g/m^2.7 in women and >49.2 g/m^2.7 in men. Patients were grouped according to presence or absence of myocardial ischemia by myocardial contrast stress echocardiography. The number of LV segments with ischemia at peak stress was taken as a measure of the extent of myocardial ischemia.

RESULTS

Myocardial ischemia was found in 52% of patients, with on average 5 ± 3 ischemic LV segments per patient. The group with myocardial ischemia had higher prevalence of LVH (23 vs. 10%, p = 0.035), while age, sex and prevalence of hypertension did not differ between groups (all p > 0.05). In multivariable regression analyses, LVH was associated with presence of myocardial ischemia (odds ratio 3.27, 95% confidence interval [1.11-9.60], p = 0.031), and larger extent of myocardial ischemia (β = 0.22, p = 0.012), independent of confounders including age, hypertension, obesity, hypercholesterolemia, calcium score and segment involvement score by CCTA.

CONCLUSIONS

LVH was independently associated with both presence and extent of myocardial ischemia in patients with stable angina and non-obstructive CAD by CCTA. These results suggest LVH as an independent contributor to myocardial ischemia in non-obstructive CAD.

CLINICAL TRIAL REGISTRATION NUMBER

ClinicalTrials.gov, identifier NCT018535271.

Mental Stress-Induced-Myocardial Ischemia in Young Patients With Recent Myocardial Infarction: Sex Differences and Mechanisms

BACKGROUND

Mental stress-induced myocardial ischemia (MSIMI) is frequent in patients with coronary artery disease and is associated with worse prognosis. Young women with a previous myocardial infarction (MI), a group with unexplained higher mortality than men of comparable age, have shown elevated rates of MSIMI, but the mechanisms are unknown.

METHODS

We studied 306 patients (150 women and 156 men) ≤61 years of age who were hospitalized for MI in the previous 8 months and 112 community controls (58 women and 54 men) frequency matched for sex and age to the patients with MI. Endothelium-dependent flow-mediated dilation and microvascular reactivity (reactive hyperemia index) were measured at rest and 30 minutes after mental stress. The digital vasomotor response to mental stress was assessed using peripheral arterial tonometry. Patients received 99mTc-sestamibi myocardial perfusion imaging at rest, with mental (speech task) and conventional (exercise/pharmacological) stress.

RESULTS

The mean age of the sample was 50 years (range, 22-61). In the MI group but not among controls, women had a more adverse socioeconomic and psychosocial profile than men. There were no sex differences in cardiovascular risk factors, and among patients with MI, clinical severity tended to be lower in women. Women in both groups showed a higher peripheral arterial tonometry ratio during mental stress but a lower reactive hyperemia index after mental stress, indicating enhanced microvascular dysfunction after stress. There were no sex differences in flow-mediated dilation changes with mental stress. The rate of MSIMI was twice as high in women as in men (22% versus 11%, P=0.009), and ischemia with conventional stress was similarly elevated (31% versus 16%, P=0.002). Psychosocial and clinical risk factors did not explain sex differences in inducible ischemia. Although vascular responses to mental stress (peripheral arterial tonometry ratio and reactive hyperemia index) also did not explain sex differences in MSIMI, they were predictive of MSIMI in women only.

CONCLUSIONS

Young women after MI have a 2-fold likelihood of developing MSIMI compared with men and a similar increase in conventional stress ischemia. Microvascular dysfunction and peripheral vasoconstriction with mental stress are implicated in MSIMI among women but not among men, perhaps reflecting women's proclivity toward ischemia because of microcirculatory abnormalities.

Global Coronary Artery Plaque Area is Associated with Myocardial Hypoperfusion in Women with Non-ST Elevation Myocardial Infarction

BACKGROUND

Women with non-ST elevation myocardial infarction (NSTEMI) have similar extent of myocardial ischemia but less obstructive coronary artery disease (CAD) than their male counterparts. We tested the impact of global coronary artery plaque area and artery tortuosity on myocardial perfusion in NSTEMI patients.

METHODS

Coronary artery plaque area was determined by quantitative angiography in 108 patients (32% women) with NSTEMI. Myocardial perfusion was assessed by contrast echocardiography in the 17 individual left ventricular segments. Artery tortuosity was defined as ≥3 curves >45° in a main coronary artery.

RESULTS

Age, prevalence of hypertension, and diabetes did not differ between sexes (all nonsignificant). Women had lower prevalence of ≥50% coronary artery stenosis (74% vs. 91%, p<0.05), while global coronary plaque area (35±22 vs. 43±21mm(2)) and the number of segments with hypoperfusion (6.9±3.7 vs. 7.2±3.4) did not differ between sexes (both p>0.07). In multivariate analysis, larger coronary artery plaque area was associated with a 35% higher risk for having severe myocardial hypoperfusion (odds ratio 1.35 [95% confidence interval 1.01-1.80], p<0.05) in the total study population, while no association between artery tortuosity and myocardial ischemia was found. Similar results were obtained in separate analysis among women and men.

CONCLUSION

In women and men with NSTEMI, the global coronary artery plaque area was an important determinant of the severity of myocardial hypoperfusion at rest independent of presence of significant coronary stenoses. These findings may expand current understanding of NSTEMI in patients with nonobstructive CAD.