Excess Risk Of Cardiovascular Events Research Articles

Prognostic value of nocturnal blood pressure and reverse-dipping status on the occurrence of cardiovascular events in hypertensive diabetic patients

Aim To assess whether reverse-dipping status is associated with cardiovascular (CV) events such as CV death, myocardial infarction (MI) or stroke in diabetic patients with hypertension. Methods A total of 97 diabetic patients underwent their first ambulatory blood pressure monitoring (ABPM 1). “Reverse dippers” were defined as patients with a nighttime systolic and/or diastolic blood pressure (BP) greater than daytime systolic and/or diastolic BP. Other patients were called “others”. A second ABPM (ABPM 2) was done after a median delay of 2.6 years. Patients were then followed for a further 2.9-year median period (total median follow-up: 5.5 years). Results After ABPM 1, CV events occurred in 53% of the reverse dippers ( n = 15) and in 29% of the others ( n = 82). Kaplan-Meier curves showed significant differences between the two groups ( P = 0.003). Mean nighttime systolic BP on ABPM 1 was 148 ± 23 mmHg and 142 ± 19 mmHg in patients who did and did not experience a CV event, respectively. With Cox analysis adjusted for confounders, a 10 mmHg increase in nighttime systolic BP was associated with a 35% increase in the risk of a CV event (hazard ratio [HR]: 1.35, P = 0.003). The HR for a CV event in reverse- versus nonreverse-dipping status was 2.79 ( P = 0.023). After ABPM 2, the relationship between the reverse-dipping status and occurrence of CV events was no longer evident ( P = 0.678). Nighttime systolic BP remained predictive of CV events ( P = 0.001) . Conclusion These findings suggest that nighttime systolic BP per se appeared to be a stronger predictor of an excess risk of CV events compared with reverse-dipping status.

Exercise Reduces Resistin and Inflammatory Cytokines in Patients With Type 2 Diabetes

Type 2 diabetes is associated with an excessive risk of cardiovascular events (1). On the other hand, physical activity reduces cardiovascular morbidity in diabetic patients (2). Resistin and numerous inflammatory markers (e.g., high-sensitivity C-reactive protein [hsCRP], interleukin [IL]-6, and IL-18) have emerged as novel predictors of cardiovascular diseases (3–5). We hypothesized that exercise could afford pleiotropic cardioprotective actions by modifying these factors in type 2 diabetic patients. The study included 60 overweight/obese patients (BMI >25 kg/m2) with type 2 diabetes who consented to participate. All patients were on a stable antidiabetes regimen (sulfonylureas and/or metfromin) but with inadequate glycemic control (A1C >6.5%). Smokers and patients receiving lipid-lowering medications, insulin, or thiazolidinediones were rejected. Those with diabetic vascular complications, life-threatening diseases, orthopedic problems, or liver and renal impairment were also excluded. Participants retained their eating patterns, and they were randomly assigned to either the exercise group ( n = 30) or control group ( n = 30). ### Exercise training All subjects were inactive, and none reported engaging in systemic (more than one time per week) sport activities before the study. Patients in the exercise group underwent a 16-week aerobic exercise training program consisting of four 45–60 min sessions per week (50–85% maximum oxygen consumption [ V o2max]). Exercise modality was based on the recent recommendations of the American Diabetes Association (6). The workload was individualized according to the initial physical fitness assessment and gradually increased with continuous electocardiographic measurement. Aerobic exercise consisted mainly of walking or running on a treadmill, cycling, and calisthenics involving upper and lower limbs. Moreover, subjects in the exercise group were encouraged to increase daily physical activities (brisk walking, …

Relationship between metabolic syndrome and platelet responsiveness to leptin in overweight and obese patients

To verify whether platelet responsiveness to leptin is associated with metabolic syndrome risk factors. Cross-sectional study. We studied 169 consecutive patients, mean age=43.6+/-9.9 years, with overweight (N=57) or obesity (N=112). Cluster analysis was used to generate three clusters based on platelet responsiveness to increasing doses of leptin. Profiles of metabolic syndrome risk factors of the three clusters were compared by discriminant analysis. Platelet responsiveness to leptin was absent in cluster 1, whereas cluster 3 had the greatest platelet aggregation response to leptin pre-incubation. Plasma leptin levels significantly decreased from cluster 1 to cluster 3 in both gender. Patients in cluster 2 had an intermediate profile of leptin responsiveness. Highest body mass index (BMI) values were more frequent in non-responders, whereas the prevalence of high waist circumference, as well as hypertriglyceridemia and hypertension, increased with increasing responsiveness to leptin from cluster 1 to cluster 3. Pattern of metabolic syndrome risk factors qualified as group specific in 69.0% of the cluster 1, 54.9% of the cluster 2 and 55.8% of the cluster 3. Circulating leptin, waist circumference, plasma triglycerides and BMI defined distinctive patterns of metabolic syndrome risk factors in the clusters. In overweight and obese outpatients, metabolic syndrome risk factors parallel to some extent platelet responsiveness to leptin. Such a correlation involves plasma leptin levels, waist circumference, plasma triglycerides and BMI, and may contribute to the excess risk of cardiovascular events in overweight and obese patients.

New perspectives on the role of aldosterone excess in cardiovascular disease.

1. Evidence from recent experimental and clinical studies suggests that excessive circulating levels of aldosterone can bring about adverse cardiovascular sequelae independent of the effects on blood pressure. Examples of these sequelae are the development of myocardial and vascular fibrosis in uninephrectomized, salt-loaded rats infused with mineralocorticoids and, in humans, an association of aldosterone with left ventricular hypertrophy, impaired diastolic and systolic function, salt and water retention causing aggravation of congestion in patients with established congestive cardiac failure (CCF), reduced vascular compliance and an increased risk of arrhythmias (resulting from intracardiac fibrosis, hypokalaemia, hypomagnesaemia, reduced baroreceptor sensitivity and potentiation of catecholamine effects). 2. These sequelae of aldosterone excess may contribute to the pathogenesis and worsen the prognosis of CCF and hypertension. 3. The heart and blood vessels may be capable of extra-adrenal aldosterone biosynthesis, raising the possibility that aldosterone may have paracrine or autocrine (and not just endocrine) effects on cardiovascular tissues. 4. The high prevalence of CCF, which is associated with secondary aldosteronism, and primary aldosteronism (PAL; recently recognized to be a much more common cause of hypertension than was previously thought) argue for an important role for aldosterone excess as a cause of cardiovascular injury. 5. The recognition of non-blood pressure-dependent adverse sequelae of aldosterone excess raises the question as to whether normotensive individuals with PAL, who have been detected as a result of genetic or biochemical screening among families with inherited forms of PAL, are at excess risk of cardiovascular events. 6. Provided that patients are carefully investigated in order to permit the appropriate selection of specific surgical (laparoscopic adrenalectomy for PAL that lateralizes on adrenal venous sampling) or medical (treatment with aldosterone antagonist medications) management and safety considerations for the use of aldosterone antagonists are kept in mind, the appreciation of a widening role for aldosterone in cardiovascular disease should provide a substantially better outlook for many patients with CCF and hypertension.

Cyclic and circadian variations in cardiovascular events

The incidence of many biologic phenomena displays a reproducible and cyclic variation. Cardiovascular disease, the most common cause of death in the United States and other developed countries, also has an intrinsic variation in events. These events are more common in winter, at the beginning of each month, on Mondays (in working people), and during the early morning hours of each day. Recent meta-analyses have quantitated the excess risk of cardiovascular events in the hours around and just after awakening. Between 6 am and noon, there is a 40% higher risk of heart attack, a 29% increased risk of cardiac death, and a 49% increased risk of stroke (compared with what would be expected if these events happened at random and were evenly distributed throughout the day). These observations have major consequences for emergency medical personnel and medical transport systems. The reasons for these observations are less clear. The circadian pattern of blood pressure (BP) and heart rate may be a major contributor, and long-term “hard endpoint” studies designed to test specific pharmacologic interventions targeting the early morning rise in BP and heart rate are underway. Individuals who work night shifts and those whose BP has a different circadian pattern have a higher risk of cardiovascular events, but may be less likely to have an increased risk of cardiovascular events in the morning.