Background: To investigate the cross-sectional and longitudinal relationships between vascular function and circulating progenitor cell (CPC) counts with respect to aging and exposure to risk factors. Methods: In 797 adult participants, CPCs were enumerated by flow cytometry as CD45med mononuclear cells expressing CD34 epitope and its subsets co-expressing CD133, and chemokine C-X-C motif receptor 4 (CXCR4+). Arterial stiffness was evaluated by tonometry-derived pulse wave velocity (PWV) and microvascular function was assessed as digital reactive hyperemia index (RHI). Results: In cross-sectional analyses, for every doubling in CD34+ cell counts, PWV was 15% higher and RHI was 9% lower, after adjusting for baseline characteristics and risk factors (p for all < 0.01). There were significant CPC-by-age-by-risk factor interactions (p <0.05) for both vascular measures. Among younger subjects (< 48 years), CPC counts were higher in those with risk factors and vascular function was better in those with higher compared to those with lower CPC counts (p for all < 0.0l). In contrast, in older participants, CPCs were not higher in those with risk factors, and vascular function was worse compared to the younger age group. A lower CPC count at baseline was an independent predictor of worsening vascular function during 2-year follow-up. Conclusion: A higher CPC count in the presence of risk factors is associated with better vascular function among younger individuals. There is no increase in CPC count with risk factors in older individuals who have worse vascular function. Moreover, a higher CPC count is associated with less vascular dysfunction with aging.
Stress may contribute to progression of coronary heart disease (CHD) through inflammation, especially among women. Thus, we sought to examine whether increased inflammatory response to stress among patients with CHD is associated with a greater risk of cardiovascular events and whether this risk is higher in women. We examined inflammatory biomarkers known to increase with mental stress (speech task), including interleukin-6 (IL-6), monocyte chemoattractant protein-1 (MCP-1), and matrix metallopeptidase-9 (MMP-9) among 562 patients with stable CHD. Inflammatory response, the difference between post-stress and resting values, was examined as a predictor of major adverse cardiovascular events (MACE) using subdistribution hazards models for competing risks adjusting for demographics, cardiovascular risk factors, and medications. MACE was defined as a composite endpoint of cardiovascular death, myocardial infarction, unstable angina with revascularization, and heart failure. All biomarkers were standardized. The mean age was 63 years (range 34–79) and 24% were women. During a median follow-up of 3 years, 71 patients experienced MACE. Overall, there was no significant association between inflammatory response to stress and risk of MACE, but there were sex-based interactions for IL-6 (p = 0.001) and MCP-1 (p = 0.01). The risk of MACE increased 56% (HR: 1.56; 95% CI: 1.21, 2.01; p = 0.001) and 30% (HR: 1.30; 95% 1.09, 1.55; p = 0.004) for each standard deviation increase in IL-6 and MCP-1 response to mental stress for women, respectively, while there was no association among men. Increased inflammation in response to stress is associated with future adverse cardiovascular outcomes among women with CHD.
Objective: To investigate differences in sleep quality by race in participants with and without a prior myocardial infarction (MI). Design: Case-control study. Setting: Emory-affiliated hospitals in Atlanta, Georgia. Participants: Two hundred seventy-three individuals (190 Black) ≤60 years of age with a verified MI in the previous 8 months, and 100 community controls (44 Black) without a history of MI. Measurements: Sleep quality was assessed using the Pittsburgh Sleep Quality Index (PSQI). Psychological factors were assessed using standardized questionnaires and clinical risk factors through medical history and chart review. Results: A significant interaction existed between race and MI status on sleep quality (P= .01), such that Black individuals with a history of MI, but not controls, reported worse sleep quality than their non-Black counterparts. Among MI cases, being Black was independently associated with higher PSQI scores after adjusting for baseline demographics (B = 2.17, 95% confidence interval 1.17, 3.17, P = .006). Clinical risk factors, psychological factors and socioeconomic status (household income and years of education) all contributed equally to explain race-related disparities in sleep among MI cases. After further adjustment for these factors, the association was attenuated and no longer significant (B = 0.70, 95% confidence interval = −0.10, 1.21, P = .26). Conclusion: Black post-MI patients, but not healthy controls, have significantly poorer sleep quality than non-Blacks. This difference is driven by a combination of factors, including clinical risk factors, psychological factors as well as adverse socioeconomic conditions among Black individuals with MI.
Greater psychological distress is associated with cognitive impairment in healthy adults. Whether such associations also exist in patients with coronary artery disease (CAD) is uncertain. We assessed cognitive function in 496 individuals with CAD using the verbal and visual memory subtests of the Wechsler Memory Scale and executive functioning measured by the Trail Making Test Parts A and B. We used a composite score of psychological distress derived through summation of Z-transformed psychological distress symptom scales (depression, posttraumatic stress, anxiety, anger, hostility and perceived stress) and scores for each individual psychological scale. Multivariable linear regression models were used to determine the association between memory scores (as outcomes) and the psychological distress scores (both composite score and individual scales). After adjusting for demographic and cardiovascular risk factors, a higher psychological distress score was independently associated with worse memory and executive functioning. Each standard deviation increase in psychological distress score was associated with 3% (95% confidence interval [CI], 1%–5%) to 5% (95% CI, 3–7%) worse cognitive performance (higher Trail A and Trail B, and lower verbal and visual memory scores). Among individuals with CAD, a higher level of psychological distress is independently associated with worse cognitive performance. These findings suggest that psychological risk factors play a role in cognitive trajectories of persons with CAD.
Objective: In patients with stable coronary artery disease (CAD), the risk of major adverse cardiovascular events (MACE) remains elevated despite treatment. The role of microvascular dysfunction on MACE beyond traditional risk indicators and inflammation is not well established. We examined whether peripheral microvascular dysfunction is associated with MACE in patients with CAD. Approach and Results: Microvascular function was measured with the Reactive Hyperemia Index (RHI) using digital peripheral arterial tonometry in 546 patients with CAD, who were followed 7 years for incident MACE. The primary end point included cardiovascular death or myocardial infarction; the secondary end point included cardiovascular death, myocardial infarction, or heart failure hospitalization. Hazard models for competing risk were used to estimate the association between RHI and MACE adjusting for age, sex, race, traditional risk factors, medications, and CAD severity. We also examined the association of baseline interleukin-6, C-reactive protein, monocyte chemoattractant protein-1, and matrix metallopeptidase-9 with RHI. Mean age was 62±9 years. Mean RHI was 2.1±0.63. After adjustment, for each 1-SD decrease in RHI, there was a 40% increase in the primary end point (hazard ratio, 1.4 [95% CI, 1.1-1.9], P=0.01) and a similar increase in the secondary end point (HR, 1.3 [95% CI, 1.1-1.7], P=0.006). Inflammatory biomarker levels were associated with greater RHI impairment (P<0.05) but did not affect the relationship between RHI and MACE. Conclusions: Peripheral microvascular dysfunction is associated with increased risk of MACE in patients with stable CAD, implicating the role of microvascular disease in the pathogenesis of adverse outcomes in patients with CAD.
Objective Mental stress-induced myocardial ischemia (MSIMI), a transient myocardial ischemic response to mental stress, is associated with poorer outcomes among patients with coronary heart disease and is more likely to occur among women. However, predictors of MSIMI are not well explored. The current study investigated the association between experiences of everyday discrimination and MSIMI among patients with recent myocardial ischemia and contrasted the results with conventional stress-induced myocardial ischemia (CSIMI). We examined sex differences in associations. Methods We studied 295 post-MI patients (145 women, 150 men). Provocation of myocardial ischemia with mental stress (speech task) and conventional stress (exercise or pharmacologic) was assessed by myocardial perfusion imaging. Frequency of exposure to everyday discrimination was assessed via questionnaire using the Everyday Discrimination Scale (EDS). Results The mean age was 51 years in both women and men, and the EDS score ranged from 10 to 38 (mean [standard deviation] = 17 [6] years). After multivariable analysis, each standard deviation increase in the EDS score (more frequent exposure) was associated with an increased odds of MSIMI (odds ratio [OR] = 1.57 [1.10-2.23]). The EDS score was not associated with CSIMI (OR = 0.86 [0.64-1.17]). Women demonstrated a twofold increase (OR = 1.96 [1.13-3.38], p =.02) in the adjusted odds of MSIMI, with each standard deviation increase in the EDS score compared with a 1.4-fold increase (OR = 1.40 [0.80-2.44], p =.24) among men; however, interaction was not statistically significant. Conclusions Among post-MI patients, everyday discrimination was positively associated with occurrence of MSIMI, but not with CSIMI; associations were more pronounced among women.
Approximately 1 in 3 US adults has hypertension, but only half have their blood pressure controlled. We identified characteristics of health care practices and systems (hereinafter practices) effective in achieving control rates at or above 70% by using data collected via applications submitted from April through June 2017 for consideration in the Million Hearts Hypertension Control Challenge. We included 96 practices serving 635,000 patients with hypertension across 34 US states in the analysis. Mean hypertension control rate was 77.1%; 27.1% of practices had a control rate of 80% or greater. Although many practices served large populations with multiple risk factors for uncontrolled hypertension, high control rates were achieved with implementation of evidenced-based strategies.