Lipoprotein-associated phospholipase A2 (Lp-PLA2) and future risk of type 2 diabetes: results from the Cardiovascular Health Study.

INTRODUCTION: Lipoprotein-associated phospholipase A2 (Lp-PLA(2)) has been consistently associated with cardiovascular disease (CVD) risk factors and predictive of CVD outcomes; furthermore, it is consistently higher among type 2 diabetics than nondiabetics. However, the relationships of circulating Lp-PLA(2) mass and activity with incident type 2 diabetes mellitus have not been examined. Therefore, the purpose of this study was to determine the association of Lp-PLA(2) mass and activity with type 2 diabetes among older adults. METHODS: We conducted analyses of Lp-PLA(2) and prevalent and incident diabetes among 5474 men and women from the Cardiovascular Health Study (1989-2007). Lp-PLA(2) mass and activity were measured in baseline plasma. Diabetes status was ascertained annually with medication inventories and repeated blood glucose measurements. Generalized linear and Cox proportional hazards models were used to adjust for confounding factors including body mass index and inflammation. RESULTS: At baseline, the top two quintiles of Lp-PLA(2) activity were significantly associated with prevalent type 2 diabetes with a multivariable relative risk = 1.35 [95% confidence interval (CI) = 1.11-1.63] for quintile 4, and relative risk = 1.33 (95% CI = 1.07-1.66) for quintile 5. Among participants free of diabetes at baseline, we found a significant positive association with both the homeostatic model assessment for insulin resistance and ß-cell function per SD increase in Lp-PLA(2) activity (P values for both <0.01). In prospective analyses, the risk of incident type 2 diabetes was significantly higher among those in the highest quintile of Lp-PLA(2) activity [multivariable hazard ratio = 1.45 (95% CI = 1.01-2.07)] compared with the lowest quintile. Lp-PLA(2) mass was not significantly associated with incident type 2 diabetes. DISCUSSION: Lp-PLA(2) activity is positively associated with insulin resistance and predicts incident type 2 diabetes among older adults independent of multiple factors associated with diabetes pathogenesis.

Apo B versus cholesterol in estimating cardiovascular risk and in guiding therapy: report of the thirty-person/ten-country panel.

There is abundant evidence that the risk of atherosclerotic vascular disease is directly related to plasma cholesterol levels. Accordingly, all of the national and transnational screening and therapeutic guidelines are based on total or LDL cholesterol. This presumes that cholesterol is the most important lipoprotein-related proatherogenic risk variable. On the contrary, risk appears to be more directly related to the number of circulating atherogenic particles that contact and enter the arterial wall than to the measured concentration of cholesterol in these lipoprotein fractions. Each of the atherogenic lipoprotein particles contains a single molecule of apolipoprotein (apo) B and therefore the concentration of apo B provides a direct measure of the number of circulating atherogenic lipoproteins. Evidence from fundamental, epidemiological and clinical trial studies indicates that apo B is superior to any of the cholesterol indices to recognize those at increased risk of vascular disease and to judge the adequacy of lipid-lowering therapy. On the basis of this evidence, we believe that apo B should be included in all guidelines as an indicator of cardiovascular risk. In addition, the present target adopted by the Canadian guideline groups of an apo B <90 mg dL(-1) in high-risk patients should be reassessed in the light of the new clinical trial results and a new ultra-low target of <80 mg dL(-1) be considered. The evidence also indicates that the apo B/apo A-I ratio is superior to any of the conventional cholesterol ratios in patients without symptomatic vascular disease or diabetes to evaluate the lipoprotein-related risk of vascular disease.

Effects of pravastatin on mortality in patients with and without coronary heart disease across a broad range of cholesterol levels. The Prospective Pravastatin Pooling project.

AIMS: To assess the effects of pravastatin on all-cause mortality and cause-specific mortality and to compare the effects for patients with prior coronary heart disease with those for patients without, using pooled data from the Long-Term Intervention with Pravastatin in Ischaemic Disease (LIPID) study, the Cholesterol and Recurrent Events (CARE) study, and the West of Scotland Coronary Prevention Study (WOSCOPS). METHODS AND RESULTS: 13 173 patients with coronary heart disease and 6595 men with elevated cholesterol and no prior coronary disease received pravastatin, 40 mg daily, or placebo for an average of 5 to 6 years. Data were analysed according to a pre-specified, published protocol. For all three trials combined, the mortality among patients assigned pravastatin was significantly lower, at 7.9%, than the 9.8% among those assigned placebo, a relative risk reduction of 20% (95% confidence interval (CI) 12-27%, P<0.0001). Active treatment was associated with a reduction in coronary mortality (24%, 95% CI 14-33%). Larger reductions in absolute risk were estimated in those with prior coronary heart disease than in those without. CONCLUSION: Treatment with pravastatin over 5 years reduces all-cause mortality and coronary mortality in patients with and those without a history of coronary heart disease. The size of the benefit was related principally to the baseline risk.

Clinical Implications of Recent Findings from the Antihypertensive and Lipid-Lowering Treatment To Prevent Heart Attack Trial (ALLHAT) and Other Studies of Hypertension.

Several recent comparative trials in hypertension have reported that similar blood pressure reductions may not necessarily translate into similar reductions in risk for cardiovascular complications. Thus, the method used to lower blood pressure may be important. In the Antihypertensive and Lipid-Lowering Treatment To Prevent Heart Attack Trial (ALLHAT), low-dose chlorthalidone as the first-line drug was superior to doxazosin. The 25% higher risk for major cardiovascular events associated with doxazosin was attributed primarily to a doubling in the risk for heart failure. A meta-analysis of patients with type 2 diabetes mellitus suggested that despite achieving similar blood pressure reductions, angiotensin-converting enzyme inhibitors are superior to other antihypertensive drugs in reducing the risk for acute myocardial infarction and cardiovascular events, but not stroke. Although individual comparative trials have failed to show conclusively that calcium-channel blockers differ from other antihypertensive drugs, a meta-analysis that included all published trials concluded that calcium-channel blockers are inferior to other classes of drugs in reducing the risk for acute myocardial infarction and heart failure. These observations suggest not only that antihypertensive drugs may have important mechanisms of action apart from blood pressure lowering but also that effective treatment is not a matter of simply lowering blood pressure. These findings have potential implications for the regulatory approval of antihypertensive agents, revisions of treatment guidelines, the design of future randomized trials comparing different antihypertensive drugs and, most important, the selection of drugs for the treatment of hypertensive patients.

Hypertension, heart rate, use of antihypertensives, and incident prostate cancer.

PURPOSE: Recent studies have reported conflicting results on a possible relationship between hypertension, heart rate, and prostate cancer. A model has been developed suggesting that high blood pressure and high heart rate may both be markers for increased central sympathetic nervous activity, which may result in androgen-mediated stimulation of prostate cancer growth. METHODS: In this study we examined the associations between hypertension, heart rate, use of antihypertensive medications, and incident prostate cancer in a cohort of 2442 men. Data from the Cardiovascular Health Study (CHS), an NHLBI-sponsored observational study of adults age 65 or older in four U.S. communities, were analyzed using Cox proportional hazards regression. Seated systolic and diastolic blood pressures were measured using a standardized protocol at the initial clinical examination and annually at follow-up visits. Medications data were transcribed by trained interviewers from prescription medication containers brought into the clinic by participants. RESULTS: A total of 209 cases of incident prostate cancer were identified from either an ICD-9 code of 185 in hospital medical records (n = 130) or by self-report from annual surveillance interviews (n = 79). An average of 5.6 years of follow-up was available for analyses. No associations between blood pressure measures at entry into the study and prostate cancer were found, although these results may have been affected by subsequent treatment of hypertension. An association between resting heart rate (HR) equal to or greater than 80 beats per minute and incident prostate cancer was found compared to men with a rate of less than 60 beats per minute (HR: 1.6, 95% confidence interval [CI]: 1.03-2.5). An inverse association was found between risk of incident prostate cancer and use of any antihypertensive medication (HR: 0.7, 95% CI: 0.5-0.9). A test of heterogeneity found no difference between use of the specific classes of antihypertensive medication and the association with prostate cancer risk. CONCLUSIONS: These data tend to support the hypothesized causal pathway between vascular disease markers and prostate cancer.

Treatment of isolated systolic hypertension is most effective in older patients with high-risk profile.

BACKGROUND: Although present guidelines suggest that treatment of hypertension is more effective in patients with multiple risk factors and higher risk of cardiovascular events, this hypothesis was never verified in older patients with systolic hypertension. METHODS AND RESULTS: Using data from the Systolic Hypertension in the Elderly Program, we calculated the global cardiovascular risk score according to the American Heart Association Multiple Risk Factor Assessment Equation in 4,189 participants free of cardiovascular disease (CVD) and in 264 participants with CVD at baseline. In the placebo group, rates of cardiovascular events over 4.5 years were progressively higher according to higher quartiles of CVD risk. The protection conferred by treatment was similar across quartiles of risk. However, the numbers needed to treat (NNTs) to prevent one cardiovascular event were progressively smaller according to higher cardiovascular risk quartiles. In participants with baseline CVD, the NNTs to prevent one cardiovascular event were similar to those estimated for CVD-free participants in the highest-risk quartile. CONCLUSIONS: Treatment of systolic hypertension is most effective in older patients who, because of additional risk factors or prevalent CVD, are at higher risk of developing a cardiovascular event. These patients are prime candidates for antihypertensive treatment.

Developing an optimal approach to global drug safety.

An increasing number of media reports on a number of marketed drugs withdrawn because of harmful effects, a scientific report on epidemic proportions of serious adverse drug reactions in hospitalized patients, and a disturbing report on medical mistakes that includes medication errors have recently all brought drug safety into intense focus and placed it under greater scrutiny. Concerted efforts are now being made to understand the causes of drug safety problems and to find ways to reduce their frequency. An international symposium, 'Developing an Optimal Approach to Drug Safety' was held at Wake Forest University in the Fall of 2000 to identify the issues and solutions to extant problems in this area. This report summarizes the resulting discussions of global postmarketing surveillance initiatives and describes efforts to reduce medication errors, and improve global communication about drug safety.

Renal insufficiency and cardiovascular events in postmenopausal women with coronary heart disease.

OBJECTIVES: This study sought to determine the independent association of renal insufficiency with cardiovascular risk among women with known coronary heart disease (CHD). BACKGROUND: Although patients with end-stage renal disease and proteinuria are at high risk for cardiovascular events, little is known about the cardiovascular risk associated with moderate renal insufficiency. METHODS: The Heart and Estrogen/progestin Replacement Study (HERS) was a clinical trial among 2,763 women with coronary disease who were randomized to conjugated estrogen plus progestins or identical placebo and followed for a mean of 4.1 years. Women were categorized as having normal renal function (creatinine < 1.2 mg/dl; n = 2,012), mild renal insufficiency (1.2 mg/dl to 1.4 mg/dl; n = 567) and moderate renal insufficiency (>1.4 mg/dl; n = 182). We examined the independent association of renal function with incident cardiovascular events including CHD death, nonfatal myocardial infarction, hospitalization for unstable angina, stroke and transient ischemic attacks. RESULTS: Compared with women with normal renal function, those with mild and moderate renal insufficiency were older, more likely to be black, have a history of hypertension and diabetes and have higher serum levels of triglycerides and lipoprotein(a). After multivariate adjustment, both mild (relative hazards [RH] = 1.24; 95% confidence interval [CI]: 1.0 to 1.5) and moderate renal insufficiency (RH = 1.57; 95% CI: 1.2 to 2.1) were independently associated with increased risk for cardiovascular events compared with women with normal renal function. CONCLUSIONS: Renal insufficiency is an independent risk factor for cardiovascular events in postmenopausal women with known coronary artery disease. Renal function may add helpful information to CHD risk stratification.

Risk of recurrent coronary events in relation to use and recent initiation of postmenopausal hormone therapy.

BACKGROUND: The finding from the Heart and Estrogen/Progestin Replacement Study (HERS) of increased coronary risk restricted to the first year after starting postmenopausal hormone therapy raises new questions about the role of hormone therapy in women with coronary heart disease. We assessed the risk of recurrent myocardial infarction or coronary heart disease death associated with the use and recent initiation of hormone therapy in women who survived a first myocardial infarction. METHODS: The setting for this population-based inception cohort study was Group Health Cooperative, a health maintenance organization. We studied 981 postmenopausal women who survived to hospital discharge after their first myocardial infarction between July 1, 1986, and December 31, 1996. We obtained information on hormone use from the Group Health Cooperative computerized pharmacy database and identified recurrent coronary events by medical record review. RESULTS: During median follow-up of 3.5 years, there were 186 recurrent coronary events. There was no difference in the risk of recurrent coronary events between current users of hormone therapy and other women (adjusted relative hazard [RH], 0.96; 95% confidence interval [CI], 0.62-1.50). Relative to the risk in women not currently using hormones, there was a suggestion of increased risk during the first 60 days after starting hormone therapy (RH, 2.16; 95% CI, 0.94-4.95) and reduced risk with current hormone use for longer than 1 year (RH, 0.76; 95% CI, 0.42-1.36). CONCLUSION: These results are consistent with the findings from the HERS, suggesting a transitory increase in coronary risk after starting hormone therapy in women with established coronary heart disease and a decreased risk thereafter.

Isoprostane 8-epi-PGF2alpha is frequently increased in patients with muscle pain and/or CK-elevation after HMG-Co-enzyme-A-reductase inhibitor therapy.

BACKGROUND: Muscle pains with or without CK-elevation are among the most frequently observed side-effects in patients with hyperlipoproteinemia on various statins. The pathophysiological background, however, remains obscure. METHODS: We examined isoprostane 8-epi-PGF2alpha, a marker of in-vivo oxidation injury, in plasma, serum and urine in these patients at baseline, when muscle problems manifested and different time intervals after withdrawing the respective statin. A healthy control group and a group of untreated patients with hyperlipoproteinemia were run as controls. RESULTS: The majority of patients with muscular side-effects show elevated 8-epi-PGF2alpha in plasma and urine, whereas serum values were elevated only to a lesser extent. Stopping statin therapy or successfully changing to another member of this family of compounds resulted in a normalization of the values in all patients. CONCLUSION: These findings indicate a significant involvement of oxidative injury in the muscular side-effects of statins in patients suffering from hyperlipoproteinemia.

Usefulness of T-axis deviation as an independent risk indicator for incident cardiac events in older men and women free from coronary heart disease (the Cardiovascular Health Study).

T-axis shift has been reported to be an indicator of increased mortality risk. We evaluated the association of spatial T-axis deviation with incident coronary heart disease (CHD) events in older men and women free from clinically overt CHD. Spatial T-axis deviation was measured from the standard 12-lead electrocardiogram of a subgroup of 4,173 subjects considered free of CHD at baseline in the Cardiovascular Health Study, a prospective cohort study of risk factors for CHD and stroke in older men and women. Cox regression analysis was used to evaluate the association of altered repolarization with the risk of incident CHD events. The prevalence of marked T-axis deviation (> or =45 degrees ) was 12%. During the median follow-up of 7.4 years, there were 161 CHD deaths, 743 deaths from all causes, and 679 incident CHD events. Adjusting for demographic and clinical risk factors, including other electrocardiographic abnormalities, there was a nearly twofold excess risk of CHD death, and approximately a 50% excess risk of incident CHD and all-cause mortality for those with marked T-axis deviation. From other electrocardiographic abnormalities, only QT prolongation was associated with excess risk for incident CHD comparable to that for abnormal T-axis deviation. These results suggest that T-axis deviation is an easily quantified marker for subclinical disease and an independent indicator for the risk of incident CHD events in older men and women free of CHD.

Association between blood pressure level and the risk of myocardial infarction, stroke, and total mortality: the cardiovascular health study.

BACKGROUND: Recent reports have drawn attention to the importance of pulse pressure as a predictor of cardiovascular events. Pulse pressure is used neither by clinicians nor by guidelines to define treatable levels of blood pressure. METHODS: In the Cardiovascular Health Study, 5888 adults 65 years and older were recruited from 4 US centers. At baseline in 1989-1990, participants underwent an extensive examination, and all subsequent cardiovascular events were ascertained and classified. RESULTS: At baseline, 1961 men and 2941 women were at risk for an incident myocardial infarction or stroke. During follow-up that averaged 6.7 years, 572 subjects had a coronary event, 385 had a stroke, and 896 died. After adjustment for potential confounders, systolic blood pressure (SBP), diastolic blood pressure (DBP), and pulse pressure were directly associated with the risk of incident myocardial infarction and stroke. Only SBP was associated with total mortality. Importantly, SBP was a better predictor of cardiovascular events than DBP or pulse pressure. In the adjusted model for myocardial infarction, a 1-SD change in SBP, DBP, and pulse pressure was associated with hazard ratios (95% confidence intervals) of 1.24 (1.15-1.35), 1.13 (1.04-1.22), and 1.21 (1.12-1.31), respectively; and adding pulse pressure or DBP to the model did not improve the fit. For stroke, the hazard ratios (95% confidence intervals) were 1.34 (1.21-1.47) with SBP, 1.29 (1.17-1.42) with DBP, and 1.21 (1.10-1.34) with pulse pressure. The association between blood pressure level and cardiovascular disease risk was generally linear; specifically, there was no evidence of a J-shaped relationship. In those with treated hypertension, the hazard ratios for the association of SBP with the risks for myocardial infarction and stroke were less pronounced than in those without treated hypertension. CONCLUSION: In this population-based study of older adults, although all measures of blood pressure were strongly and directly related to the risk of coronary and cerebrovascular events, SBP was the best single predictor of cardiovascular events.

Are all angiotensin-converting enzyme inhibitors interchangeable?

In the treatment of most medical conditions, there are many choices. A critical question for practicing clinicians is: "Are all drugs within a class interchangeable?" In the past decade, the market has seen a proliferation of drugs within popular drug classes. The original drugs within a class typically have better scientific documentation than the newer ones, which are often referred to as "me-too" drugs. Due to a lesser financial investment, the latter may be available at a lower cost. Good reasons exist for grouping drugs, however, there is no accepted definition of the term "class effect." Although members of a drug class share main actions, they may have clinically important differences in terms of efficacy and safety. There are many such examples in the literature. This article reviews the class effect concept as it applies to the angiotensin-converting enzyme (ACE) inhibitors. Only half of the 10 ACE inhibitors available in the U.S. have been shown to improve survival and reduce morbidity in patients with heart failure or myocardial infarction. It is unknown whether the other five have the same safety and efficacy profiles or what their optimal doses are. Thus, we do not know whether all ACE inhibitors are fully interchangeable. The practice of medicine ought to be based on solid scientific evidence, not on assumptions or extrapolations. For our patients, such practice is a legitimate expectation. Therefore, it seems prudent to recommend that patients requiring ACE inhibitor therapy be prescribed one that has been proven effective and safe.

Risk factors for hospitalized gastrointestinal bleeding among older persons. Cardiovascular Health Study Investigators.

OBJECTIVES: We sought to estimate the incidence of hospitalization for upper and lower gastrointestinal bleeding among older persons and to identify independent risk factors. DESIGN: Prospective cohort study. SETTING: The Cardiovascular Health Study (CHS). PARTICIPANTS: 5,888 noninstitutionalized men and women age 65 years or older in four U.S. communities enrolled in the CHS. MEASUREMENTS: Gastrointestinal bleeding events during the period 1989 through 1998 were identified using hospital discharge diagnosis codes and confirmed by medical records review. Risk-factor information was collected in a standardized fashion at study baseline and annually during follow-up. RESULTS: Among CHS participants (mean baseline age 73.3 years, 42% male), the incidence of hospitalized gastrointestinal bleeding was 6.8/1,000 person-years. In multivariate analyses, advanced age, male sex, unmarried status, cardiovascular disease, difficulty with daily activities, use of multiple medications, and use of oral anticoagulants were independent risk factors. Compared with nonsmokers, subjects who smoked more than half a pack per day had a multivariate-adjusted hazard ratio (HR) of 2.14 (95% confidence interval [CI] = 1.22-3.75) for upper gastrointestinal bleeding and a multivariate-adjusted HR of 0.21 (95% CI = 0.03-1.54) for lower gastrointestinal bleeding. Aspirin users did not have an elevated risk of upper gastrointestinal bleeding (HR = 0.76, 95% CI = 0.52-1.11), and users of other nonsteroidal anti-inflammatory drugs had a HR of 1.54 (95 % CI = 0.99-2.36). Low ankle-arm systolic blood pressure index was associated with higher risk of gastrointestinal bleeding among subjects with clinical cardiovascular disease but not among those without clinical cardiovascular disease. CONCLUSION: This study identifies risk factors for gastrointestinal bleeding, such as disability, that may be amenable to modification. The findings will help clinicians to identify older persons who are at high risk for gastrointestinal bleeding.

Frequency and predictors of stroke death in 5,888 participants in the Cardiovascular Health Study.

BACKGROUND: Few population-based studies have examined in detail issues of stroke-related deaths in elderly people. METHODS: Participants in the Cardiovascular Health Study (CHS) are 65 years of age or older, have had extensive baseline evaluations, and have been followed-up for fatal and nonfatal cardiovascular and cerebrovascular disease outcomes. Investigators adjudicated these outcomes and classified strokes by types and subtypes. RESULTS: Over 7 years, 1,310 (22.2%) of 5,888 participants died, and 455 (7.7%) experienced incident stroke. For the 5,888, stroke mortality was 3.2 per 1,000 person-years. For the 455, it was 36.1 per 1,000 person-years, with the most lethal type being hemorrhagic and the ischemic subtype being cardioembolic. After controlling for age and stroke type, the only other independent predictor of death after any stroke was poor performance on a timed walk measured before the incident stroke. Considering only ischemic stroke, the independent predictors of death were African American race and poor performance on timed walk. CONCLUSION: In CHS, death attributable to stroke is common. As in other studies, the most lethal stroke type was hemorrhagic, and ischemic stroke subtype, cardioembolic. Slow walking, possibly a measure of frailty, was associated with an increased risk of death of stroke. Finally, African Americans faced a greater risk of death than others after an ischemic stroke.