Effect of type 2 diabetes mellitus on left ventricular geometry and systolic function in hypertensive subjects: Hypertension Genetic Epidemiology Network (HyperGEN) study

The influence of lifestyle on cardiovascular risk factors. Analysis using a neural network

The cardiovascular pathologies are the most common causes of death in the elderly patient. To single out the main risk factors in order to effectively prevent the onset of the disease, the authors experimented a special computerized tool, the neural network, that works out a mathematical relation that can obtain certain data (defined as output) as a function of other data (defined as input). Data were processed from a sample of 276 subjects of both sexes aged 26-69 years old. The output data were: high/low cholesterolemia, HDL cholesterol, triglyceridemia with respect to an established cut-off; the input data were: sex, age, build, weight, married/single, number of children, number of cigarettes smoked/day, amount of wine and number of cups of coffee. We conclude that: (i) a relationship exists, deduced from a neural network, between a set of input variables and a dichotomous output variable; (ii) this relationship can be expressed as a mathematical function; (iii) a neural network, having learned the data on a sufficiently large population, can provide valid predictive data for a single individual with a high probability (up to 93.33%) that the response it gives is correct. In this study, such a result is found for two of the three cardiovascular risk indicators considered (cholesterol and triglycerides); (iv) the repetition of the neural network analysis of the cases in question after a "pruning" operation provided a somewhat less good performance; (v) a statistical analysis conducted on those same cases has confirmed the existence of a strong relationship between the input and the output variables. Therefore the neural network is a valid instrument for providing predictive in a single subject on cardiovascular pathology risks.

Diabetes mellitus and heart failure: basic mechanisms, clinical features, and therapeutic considerations

Diabetic cardiomyopathy encompasses the spectrum from subclinical disease to the full-blown syndrome of congestive heart failure. The prevalence of type 2 diabetes mellitus is increasing at an alarming rate in the western world. and with it, the frequency of diabetes-related heart failure. There is at least early suggestion that target-driven, long-term, intensified intervention that is aimed at multiple risk factors in patients who have type 2 diabetes and microalbuminuria may reduce the risk of macrovascular (cardiovascular) and micro-vascular complications by approximately 50%. Thus, it is imperative that patients, particularly those who are at risk for the cardiovascular dysmetabolic syndrome, be screened aggressively for the presence of glucose intolerance and diabetes. When detected, all metabolic and cardio-vascular parameters should be evaluated and treated aggressively to reach currently recommended clinical targets. Such action will result in great benefit for patients by reducing morbidity and mortality and improving quality of life and will reduce the financial burden that is associated with this epidemic disease.

Metabolic syndrome and target organ damage in untreated essential hypertensives

BACKGROUND

The prevalence and the relationship between metabolic syndrome, and target organ damage (TOD) in essential hypertensive patients has not been fully explored to date.

OBJECTIVE

To investigate the association between metabolic syndrome, as defined by the ATP III report, and cardiac and extracardiac TOD, as defined by the 2003 ESH-ESC guidelines for management of hypertension, in a large population of never-treated essential hypertensives.

METHODS

A total of 447 grade 1 and 2 hypertensive patients (mean age 46 +/- 12 years) who were attending a hypertension hospital outpatient clinic for the first time underwent the following procedures: (i) physical examination and repeated clinic blood pressure measurements; (ii) routine examinations; (iii) 24-h urine collection for microalbuminuria; (iv) 24-h ambulatory blood pressure monitoring; (v) echocardiography; and (vi) carotid ultrasonography. Metabolic syndrome was defined as involving at least three of the following alterations: increased waist circumference, increased triglycerides, decreased high-density lipoprotein cholesterol, increased blood pressure, or high fasting glucose. Left ventricular hypertrophy (LVH) was defined according to two different criteria: (i) 125 g/m in men and 110 g/m in women; (ii) 51 g/h in men and 47 g/h in women.

RESULTS

The 135 patients with metabolic syndrome (group I) were similar for age, sex distribution, known duration of hypertension and average 24-h, daytime and night-time ambulatory blood pressure to the 312 patients without it (group II). The prevalence of altered left ventricular patterns (LVH and left ventricular concentric remodelling) was significantly higher in group I (criterion a = 30%, criterion b = 42%) than in group II (criterion a = 23%, criterion b = 30%, P < 0.05 and P < 0.01, respectively). A greater urinary albumin excretion (17 +/- 35 versus 11 +/- 23 mg/24 h, P = 0.04) was also found in group I compared to group II. There were no significant differences between the two groups in the prevalence of carotid intima-media thickening and plaques.

CONCLUSIONS

These results from a representative sample of untreated middle-aged hypertensives show that: (i) the metabolic syndrome is highly prevalent in this setting and (ii) despite similar ambulatory blood pressure values, patients with metabolic syndrome have a more pronounced cardiac and extracardiac involvement than those without it.

How much echo left ventricular hypertrophy would be missed in diabetics by applying the Losartan Intervention For Endpoint Reduction electrocardiogram criteria to select patients for angiotensin receptor blockade?

OBJECTIVE

The Losartan Intervention For Endpoint Reduction (LIFE) study demonstrated a clear mortality benefit in treating hypertensive patients with electrocardiogram (ECG) evidence of left ventricular hypertrophy (LVH) with losartan rather than atenolol. Previous studies have also shown that identifying and treating echo LVH is associated with prognostic benefits in hypertensive subjects, and is independent of the presence of ECG LVH. We sought to determine how many cases of echo LVH would be missed by applying the ECG criteria for LVH used in the LIFE study.

DESIGN

A prospective study of 219 patients with type 2 diabetes recruited from the hospital diabetic clinic.

METHODS

Fifteen ECG criteria were assessed on each subject and compared with the presence or absence of LVH on echocardiography.

RESULTS

All the proposed ECG criteria are poor at identifying echo LVH in people with diabetes.

CONCLUSION

Using ECG LVH to select patients for angiotensin receptor blockade would lead to many diabetics with echo LVH missing out on the benefits of treatment. This assumes that the benefits seen in the LIFE study would also occur if the LIFE strategy were extended to echo LVH patients as well as to ECG LVH patients.

Left ventricular concentric geometry is associated with impaired relaxation in hypertension: the HyperGEN study

AIMS

We tested the hypothesis that abnormal left ventricular (LV) relaxation is associated with concentric LV geometry.

METHODS AND RESULTS

Doppler LV filling properties were studied in 1384 hypertensive participants without cardiovascular disease, from the HyperGEN population (731 women, 784 obese, 236 diabetic) and compared in four LV geometry groups; normal, concentric remodelling (3.5%), eccentric (23%), and concentric LV hypertrophy (4%), based on echocardiographic LV mass index (in g/m(2.7)). Abnormal LV relaxation was identified by European Society of Cardiology criteria in 275 subjects (20%). After accounting for significant confounders, E/A ratio and isovolumic relaxation time were not related to the presence of LV hypertrophy, but indicated abnormal relaxation when LV geometry was concentric (both P<0.0001). Deceleration time of E velocity was prolonged with LV hypertrophy (P<0.03), but the behaviour in relation to concentric LV geometry differed in the presence (prolonged) or absence (reduced) of LV hypertrophy (P=0.05), a difference independently related to the magnitude of both transmitral gradients and stroke volume (all P<0.05). Logistic regression showed that, compared with normal LV geometry, the odds of abnormal LV relaxation was 2.3-fold greater when LV geometry was concentric and that LV hypertrophy conferred a borderline higher risk than normal LV mass.

CONCLUSIONS

In hypertensive individuals without prevalent cardiovascular disease from a multi-ethnic population-based sample, delayed LV relaxation is independently associated with concentric LV geometry.

A novel approach to treatment of hypertension in diabetic patients - a multicenter, double-blind, randomized study comparing the efficacy of combination therapy of Eprosartan versus Ramipril with low-dose Hydrochlorothiazide and Moxonidine on blood pressure levels in patients with hypertension and associated diabetes mellitus type 2 - rationale and design [ISRCTN55725285]

Hypertension and diabetes mellitus are closely interrelated and coexist in as many as two-thirds of patients with type 2 diabetes. The consequent risk of such an association is an accelerated development of atherosclerotic cardiovascular disease and nephropathy complications.In choosing an antihypertensive agent, effectiveness needs to be accompanied by favourable metabolic, cardioprotective, and nephroprotective properties. Given the multifactorial nature of hypertension, the approach that has gained widespread agreement is treatment with more than one agent. Agents with different mechanisms of action increase antihypertensive efficacy because of synergistic impacts on the cardiovascular system. Combination therapy allows the use of lower doses of each antihypertensive agent which accounts for the excellent tolerability of combination products.The aim of the present study is to quantify the efficacy of combination therapy of Eprosartan 600 mg respectively Ramipril 5 mg with low-dose Hydrochlorothiazide and Moxonidine on blood pressure levels in patients with essential hypertension and associated diabetes mellitus type 2.The use of monotherapy (Eprosartan or Ramipril) followed by addition of low-dose Hydrochlorothiazide as second agent and of Moxonidine as a third agent will be individualized to the severity of hypertension in the particular patient and to his/her degree of response to current treatment.

Elevated plasma levels of Nt-proBNP in patients with type 2 diabetes without overt cardiovascular disease

OBJECTIVE

The NH(2)-terminal portion of the precursor of brain natriuretic peptide (Nt-proBNP) has been reported to be elevated in left ventricular dysfunction. This peptide is a split product from the proBNP molecule, and its level in the circulation is not, as the mature BNP peptide, dependent on the peripheral number of BNP receptors. We aimed to test the hypothesis that asymptomatic left ventricular dysfunction (ALVD), as estimated by Nt-proBNP, would be more prevalent in patients with type 2 diabetes without overt cardiovascular disease in comparison with matched control subjects.

RESEARCH DESIGN AND METHODS

The study population consisted of 253 patients with type 2 diabetes and 230 matched control subjects aged 40-70 years without any overt heart disease from primary care centers in Western Finland and Southern Sweden. Nt-proBNP was measured in plasma by competitive enzyme immunosorbent assay.

RESULTS

Patients with type 2 diabetes were shown to have higher Nt-proBNP values (360.9 pmol/l [262.6-467.9]) than control subjects (302.7 pmol/l [215.4-419.2]) (P < 0.001). Nt-proBNP levels were independently related to diabetes after adjustment for age, sex, systolic and diastolic blood pressure, BMI, heart rate, drug treatment, serum creatinine, and cystatin C.

CONCLUSIONS

Our data suggest that the secretion of Nt-proBNP is increased in type 2 diabetic patients with no overt heart disease, suggesting that type 2 diabetes is associated with a higher prevalence of ALVD than hitherto thought. Nt-proBNP may thus serve as a screening instrument to select patients with type 2 diabetes who could benefit from an echocardiographical examination.

Comparison of effects of exercise and diuretic on left ventricular geometry, mass, and insulin resistance in older hypertensive adults

To compare the effects of exercise training and hydrochlorothiazide on left ventricular (LV) geometry and mass, blood pressure (BP), and hyperinsulinemia in older hypertensive adults, we studied 28 patients randomized either to a group (age 66.4 ± 1.3 yr; n = 16) that exercised or to a group (age 65.3 ± 1.2 yr; n = 12) that received hydrochlorothiazide for 6 mo. Endurance exercise training induced a 15% increase in peak aerobic power. The reduction in systolic BP was twofold greater with thiazide than with exercise (26.6 ± 12.2 vs. 11.5 ± 10.9 mmHg). Exercise and thiazide reduced LV wall thickness, LV mass index (14% in each group), and the LV wall thickness-to-radius ratio ( h/ r) similarly (exercise: before 0.48 ± 0.2, after 0.42 ± 0.01; thiazide: before 0.47 ± 0.04, after 0.40 ± 0.04; P = 0.017). The reductions in systolic BP and h/ r were correlated in the exercise group ( r = 0.70, P = 0.005) but not in the thiazide group. Exercise training reduced glucose-stimulated hyperinsulinemia (before: 13.65 ± 2.6 vs. 9.84 ± 1.5 mU·ml−1·min; P = 0.04) and insulin resistance. Thiazide did not affect plasma insulin levels. The results suggest that although exercise is less effective in reducing systolic BP than thiazide, it can induce regression of LV hypertrophy similar in magnitude to thiazide. Unlike hydrochlorothiazide, exercise training can improve insulin resistance and aerobic capacity in older hypertensive people.

Direct effects of high glucose and insulin on protein synthesis in cultured cardiac myocytes and DNA and collagen synthesis in cardiac fibroblasts

The present study examined the direct effects of high glucose and insulin on protein synthesis in cardiac myocytes and DNA and collagen synthesis in cardiac fibroblasts. Cultured rat cardiac myocytes and fibroblasts were grown in media containing normal glucose, high glucose, or osmotic control, and incubated with or without insulin. In cardiac myocytes, high glucose had no effect, but insulin increased protein synthesis and atrial natriuretic peptide (ANP) secretion and gene expression. The extracellular signal-regulated protein kinase (ERK)/mitogen-activated protein kinase (MAPK) inhibitor and the protein kinase C (PKC) inhibitor blocked insulin-induced protein synthesis. In cardiac fibroblasts, high glucose and osmotic control media increased DNA synthesis. Collagen synthesis and fibronectin and transforming growth factor-beta1 (TGF-beta1) mRNA expression were stimulated by high glucose, but not by osmotic control. Insulin increased DNA and collagen synthesis in fibroblasts, and the insulin-induced increase in DNA synthesis was blocked by the phosphatidylinositol 3 kinase (PI3K) inhibitor. Our findings suggest that cardiomyocyte protein synthesis is mainly regulated by insulin rather than high glucose and both high glucose and insulin contribute to fibroblast DNA and collagen synthesis. High glucose accelerates fibroblast DNA synthesis and collagen synthesis, and fibronectin and TGF-beta1 mRNA expression, dependent or independent of osmotic stress. Insulin regulates myocyte protein synthesis and fibroblast DNA synthesis through different intracellular mechanisms.

Hospitalization for heart failure in the presence of a normal left ventricular ejection fraction

OBJECTIVES

We conducted a prospective multicenter registry in a large metropolitan area to define the clinical characteristics, hospital course, treatment, and factors precipitating decompensation in patients hospitalized for heart failure with a normal ejection fraction (HFNEF).

BACKGROUND

The clinical profile of patients hospitalized for HFNEF has been characterized by retrospective analyses of hospital records and state data banks, with few prospective single-center studies.

METHODS

Patients hospitalized for heart failure (HF) at 24 medical centers in the New York metropolitan area and found to have a left ventricular (LV) ejection fraction of > or 50% within seven days of admission were included in this registry. Patient demographics, signs and symptoms of HF, coexisting and exacerbating cardiovascular and medical conditions, treatment, laboratory tests, procedures, and hospital outcomes data were collected. Analysis by gender and race was prespecified.

RESULTS

Of 619 patients, 73% were women, who were on average four years older than men (72.8 +/- 14.1 years vs. 68.6 +/- 13.8 years, p < 0.001). Black non-Hispanic patients comprised 30% of the study population. They were eight years younger than other patients (66.0 +/- 14.2 years vs. 74 +/- 13.5 years p < 0.001). Co-morbid conditions and their prevalence were: hypertension, 78%; increased LV mass, 82%; diabetes, 46%; and obesity, 46%. Before clinical decompensation that precipitated hospitalization, 86% of patients had chronic symptoms compatible with New York Heart Association functional classes II to IV. Factors precipitating clinical decompensation were identified in 53% of patients. In-hospital mortality was 4.2%.

CONCLUSIONS

Patients hospitalized for HFNEF are most often chronically incapacitated elderly women with a history of hypertension and increased LV mass. Reasons for clinical decompensation are identified in only one-half of patients.

Left ventricular mass increases with deteriorating glucose tolerance, especially in women: independence of increased arterial stiffness or decreased flow-mediated dilation: the Hoorn study

OBJECTIVE

Type 2 diabetes and impaired glucose metabolism (IGM) are associated with an increased cardiovascular disease (CVD) risk. Increased left ventricular mass (LVM) is thought to increase CVD risk through several unfavorable cardiac changes. Type 2 diabetes and IGM are associated with increased LVM, but the underlying mechanism is unclear. We investigated the association between glucose tolerance status (GTS) and LVM and explored whether any such association could be mediated through increased arterial stiffness, impaired endothelial function, or the presence of atherosclerosis.

RESEARCH DESIGN AND METHODS

We used ultrasound to measure LVM, carotid and femoral stiffness, carotid-femoral transit time, and flow-mediated vasodilation (FMD) and tonometry to estimate compliance and augmentation index. The study population (n = 780) consisted of 287 individuals with normal glucose metabolism (NGM), 179 with IGM, and 314 with type 2 diabetes, and the mean age was 68.4 years.

RESULTS

In women, after adjusting for age, height, BMI, and mean arterial pressure, LVM increased significantly with deteriorating GTS (LVM 157 g in NGM, 155 g in IGM, and 169 g in type 2 diabetes; P for trend <0.018). Additional adjustment for arterial stiffness, FMD, or the presence of atherosclerosis did not materially alter the results, even though these variables were significantly associated with both GTS and LVM. Indexes of hyperglycemia/-insulinemia or insulin resistance explained at most 7% of the association between GTS and LVM. In men, no statistically significant associations were observed.

CONCLUSIONS

Our data expand the conceptual view of the pathogenesis of GTS-related changes in LVM because we show that the increase in LVM in women is independent of increased arterial stiffness, impaired FMD, or the presence of atherosclerosis. In addition, we show that this increase in LVM is only minimally explained by indexes of hyperglycemia/-insulinemia or insulin resistance. Our data may, in part, explain the increased CVD risk seen in women with deteriorating GTS.

Increased prevalence of left ventricular hypertrophy in hypertensive women with type 2 diabetes mellitus

BACKGROUND

Left ventricular hypertrophy (LVH) is a powerful independent risk factor for cardiovascular morbidity and mortality among hypertensive patients. Data regarding relationships between diabetes and LVH are controversial and inconclusive, whereas possible gender differences were not specifically investigated. The goal of this work was to investigate whether gender differences in left heart structure and mass are present in hypertensive patients with type 2 diabetes.

METHODS

Five hundred fifty hypertensive patients with at least one additional cardiovascular risk factor (314 men and 246 women, age 52 to 81, mean 66 +/- 6 years), were enrolled in the present analysis. In 200 (36%) of them--108 men and 92 women--type 2 diabetes mellitus was found upon enrollment. End-diastolic measurements of interventricular septal thickness (IVS), LV internal diameter, and posterior wall thickness were performed employing two-dimensionally guided M-mode echocardiograms. LVH was diagnosed when LV mass index (LVMI) was > 134 g/m2 in men and > 110 g/m2 in women.

RESULTS

Mean LVMI was significantly higher among diabetic vs. nondiabetic women (112.5 +/- 29 vs. 105.6 +/- 24, p = 0.03). In addition, diabetic women presented a significantly higher prevalence of increased IVS thickness, LVMI and left atrial diameter on intra-gender comparisons. The age adjusted relative risk for increased LVMI in diabetics vs. nondiabetics was 1.47 (95% CI: 1.0-2.2) in females and only 0.8 (0.5-1.3) in males.

CONCLUSION

Type 2 diabetes mellitus was associated with a significantly higher prevalence of LVH and left atrial enlargement in hypertensive women.

Diabetes Mellitus and Heart Failure

The metabolic abnormalities associated with diabetes mellitus result in macrovascular and microvascular complications in multiple organ systems; it is the cardiovascular impact that accounts for the greatest morbidity and mortality associated with this disease. Heart failure, both with reduced and preserved systolic function, is a major complication, arising from the frequent associations with coronary atherosclerosis, hypertension, and a specific heart muscle dysfunction (cardiomyopathy) that occurs independently of coronary artery disease. Hyperglycemia, insulin resistance, and hypertension, together with activation of both the circulating and the tissue renin-angiotensin-aldosterone systems, contribute to structural fibrosis and autonomic neuropathy. Thus, it becomes imperative to identify cardiac abnormalities early in the course of both type 1 and type 2 diabetes to allow early and aggressive intervention to control glucose and blood pressure and to normalize blood lipid profiles. Patients with diabetes should be treated to secondary prevention targets, including blood pressure less than 130/80 mm Hg and low-density lipoprotein cholesterol level less than 100 mg/dL. Angiotensin-converting enzyme inhibitors, angiotensin-receptor blockers,beta blockers, calcium channel-blockers, statins, and aspirin have all been demonstrated to significantly reduce cardiovascular morbidity and mortality in patients with diabetes.

Relation of left ventricular hypertrophy to inflammation and albuminuria in adults with type 2 diabetes: the strong heart study

OBJECTIVE

To evaluate in adults with type 2 diabetes the extent to which the relation of left ventricular hypertrophy (LVH) to markers of systemic inflammation (fibrinogen and high-sensitivity C-reactive protein [hsCRP]) are affected by microangiopathy.

RESEARCH DESIGN AND METHODS

We selected adults with type 2 diabetes using American Diabetes Association criteria from a population-based cohort, excluding those with medical history or electrocardiographic evidence of coronary heart disease or dialysis-dependent renal failure. LVH was assessed by echocardiogram.

RESULTS

Of the 1299 eligible participants, 384 (29.6%) had LVH, which was associated with higher BMI, hsCRP, fibrinogen, and albuminuria in univariate analyses. After controlling for significant confounders, fibrinogen and albuminuria were higher in the presence of LVH (both P < 0.01), whereas hsCRP was not (P = 0.2), mostly because of the confounding effect of BMI. Adjustment for albuminuria abolished the relation of LVH to higher fibrinogen (P = 0.2). However, fibrinogen was significantly higher in participants with LVH among those without pathologic levels of albuminuria (<30 mg/g creatinuria), but not independent of BMI. Although hsCRP and fibrinogen were moderately correlated, fibrinogen, but not CRP, showed a significant relation with albuminuria.

CONCLUSIONS

In adults with type 2 diabetes, echocardiographic LVH is associated with susceptibility to atherothrombosis and increased albuminuria, which is a marker of microangiopathy and endothelial dysfunction that appears in turn to be a relevant pathogenetic link between LVH and inflammation. However, in the absence of significant microalbuminuria, elevated BMI is a relevant pathogenetic factor in the relation of LVH to increased levels of markers of inflammation, potentially preceding development of significant albuminuria. In the presence of microangiopathy, we found that the atherothrombotic risk profile associated with LVH was independent of BMI and possibly reflected the association of LVH with a higher degree of endothelial dysfunction.

Influence of fat-free mass on detection of appropriateness of left ventricular mass: the HyperGEN Study

OBJECTIVES

To evaluate the differences between using height(2.7) or fat-free mass for assessment of the appropriateness of left ventricular mass (LVM) in relation to hemodynamic load, and to evaluate the performance of Doppler as compared with M-mode-derived stroke volume for computation of predicted values of LVM.

DESIGN

Cross-sectional.

SETTING

Population-based.

PARTICIPANTS

We studied 2299 participants from the Hypertension Genetic Epidemiology Network Study (prevalent cardiovascular disease in 342).

OUTCOME MEASURES

Individual predicted values of LVM were generated by equations using sex, stroke work (systolic blood pressure x stroke volume by either Doppler or M-mode) and either height(2.7) or fat-free mass, as measures of body build, in 228 normotensive, non-obese, non-diabetic participants. Observed LVM was divided by the predicted value and evaluated as 'excess of LVM'.

RESULTS

Among 1957 participants without prevalent cardiovascular disease, obese individuals (n = 1008) were slightly younger than non-obese individuals, whereas diabetic participants (n = 294) were slightly older. Excess of LVM was positively related to body mass index (BMI), independently of echocardiographic method and measure of body build, especially when height(2.7) and m-mode stroke work were used, and was greatest in the presence of concentric left ventricular hypertrophy (P < 0.0001). Excess LVM by height(2.7) was progressively greater than that by fat-free mass, as BMI increased (P < 0.0001). In analyses of covariance of association of prevalent cardiovascular disease with age, sex, race, BMI, and excess of LVM (by each method), methods using height(2.7) were more associated with prevalent cardiovascular disease than were methods using fat-free mass (P < 0.02).

CONCLUSIONS

Deviation of LVM from values that compensate hemodynamic load can be similarly identified using different measures of body build and methods to generate stroke work. However, the use of height(2.7) to compute LVM as a percentage of that predicted appears to identify deviations from compensatory values that are independently related to prevalent cardiovascular disease more effectively than does the use of fat-free mass.

Prognostic implications of ejection fraction from linear echocardiographic dimensions: the Strong Heart Study

BACKGROUND

Although echocardiography is commonly used to assess left ventricular (LV) systolic function, few data are available concerning the prognostic significance of LV ejection fraction (EF) calculated from linear echocardiographic measurements or 2-dimensional (2-D) wall motion scores in population-based samples.

METHODS

Echocardiography was used in the second Strong Heart Study (SHS) examination to calculate LV EF in 2948 American Indians without prevalent coronary heart disease; 2923 had 2-D wall motion scores.

RESULTS

Mildly and severely reduced LV EF occurred in 10% and 2% of participants, was associated with older age, male sex, higher systolic pressure, heart rate and markers of renal disease and inflammation. During 37 +/- 9 months follow-up, cardiovascular death occurred in 2%, 5% and 12% of participants with normal, mildly reduced and severely reduced EF; all cause mortality rates were 6%, 10% and 32% (both P <.001). In Cox proportional hazards analyses, adjusting for covariates, cardiovascular death was higher with mildly reduced EF (risk ratio [RR] 2.9, 95% CI 1.6-5.4, P =.0007) and especially with severely reduced EF (RR 6.9, 95% CI 3.0-15.9, P <.0001); all-cause mortality was increased with severe LV dysfunction (RR 4.8, 95% CI 2.8-8.1, P <.001) and marginally with mildly reduced EF (odds ratio 1.4, 95% CI 0.95-2.15, P =.08). Segmental LV dysfunction and mildly and severely reduced EF from 2-D wall motion scores were associated with 3.3-fold (95% CI 1.1-9.4, P =.02), 3.5-fold (95% CI 2.1-5.8) and 3.8-fold (95% CI 1.9-7.6) (all P <.001) increased rates of cardiovascular death.

CONCLUSIONS

LV EF from linear echocardiographic measurements as well as segmental LV dysfunction and EF from 2-D wall motion scores strongly and independently predict cardiovascular mortality. Reduced EF by simple echocardiographic method has estimated population-attributable risks of about 35% for cardiovascular death and 12% for all-cause mortality in a population-based sample of middle-aged to elderly adults.

Effects of diet treatment on some biochemical and physiological parameters in patients with type 2 diabetes mellitus

The aim of the present study was to investigate the effect of diet treatment on serum glucose, triglyceride (TG), total cholesterol (TC), high density lipoprotein-(HDL) cholesterol, low density lipoprotein-(LDL) cholesterol and very low density lipoprotein-(VLDL) cholesterol levels, systolic and diastolic blood pressure and electrocardiograms (ECGs) in patients with type 2 diabetes mellitus (DM). Twenty healthy subjects (mean age 45.9 +/- 3.7 years) and newly diagnosed patients with type 2 diabetes prior to receiving diet treatment (mean age 47.6 +/- 6.2 years) were included in this study. Diabetic patients were given a standard dietary treatment that was composed of 50% to 55% carbonhydrate and 30% fat (1200 kcal for women and 1600 kcal for men) for 2 months. No diet treatment was applied for control. For both groups serum glucose, TG, TC, HDL-cholesterol, LDL-cholesterol and VLDL-cholesterol levels, systolic and diastolic blood pressure and ECGs were measured at the beginning and end of the diet treatment. Although diet treatment decreased the elevated serum glucose in diabetic patients, it still remained higher than that in the controls. Diet treatment also decreased the elevated TG and VLDL-cholesterol in diabetic patients to control values. Although heart rate and systolic blood pressure were higher, diastolic blood pressure was not different in diabetic patients than those in controls. Ventricular hypertrophy was also observed in ECGs of 10% of diabetic patients. Diet treatment normalized all of these findings, except systolic blood pressure. This study showed that diet treatment could not normalize the high systolic blood pressure in type 2 DM. Thus, an effective way of controlling blood pressure should be taken to improve healing in DM.

The determinants of left ventricular hypertrophy defined by Sokolow-Lyon criteria in untreated hypertensive patients

Left ventricular hypertrophy (LVH) measured by electrocardiography (ECG LVH) in hypertensive patients has been shown to be associated with an increased risk of cardiovascular sequelae. Analysis of the determinants predisposing to ECG LVH may be helpful in the prevention of LVH. The Department of Health and Social Security Hypertension Care Computer Project studied 2994 hypertensive patients in whom an electrocardiogram was recorded while not on treatment. LVH was determined as the voltage sum SV1+RV5 or RV6>or=35 mm using Sokolow-Lyon voltage criteria. The relations were determined between the presence of LVH or voltage sum and different variables. Untreated systolic (SBP) and diastolic (DBP) blood pressure and pulse pressure were positively related to the increasing ECG voltage, while body mass index (BMI) and serum cholesterol were inversely related. Blood glucose and age did not correlate significantly. Patients with the presence of ECG LVH were more often men, black people, smokers and users of alcohol. In multiple logistic regression analyses, SBP, DBP, male gender and black race were positively, whereas BMI was negatively related to the presence of LVH. The positive relation of smoking and negative relation of serum cholesterol concentration to the presence of ECG LVH were apparent in men but not in women. This study confirms the adverse association between ECG LVH and SBP and DBP, male gender, black race and decreased BMI. It also addresses the less well-known associations of blood glucose, cholesterol, smoking and alcohol consumption.

Development of congestive heart failure in type 2 diabetic patients with microalbuminuria or proteinuria: observations from the DIABHYCAR (type 2 DIABetes, Hypertension, CArdiovascular Events and Ramipril) study

OBJECTIVE

The DIABHYCAR (type 2 DIABetes, Hypertension, CArdiovascular Events and Ramipril) study allowed investigators to analyze factors leading to the development of congestive heart failure (CHF) in type 2 diabetic patients with abnormal urinary albumin concentration.

RESEARCH DESIGN AND METHODS

Type 2 diabetic subjects of both sexes aged >or=50 years who had a urinary albumin concentration >or=20 mg/l were randomly allocated to 1.25 mg/day ramipril or placebo in addition to their usual treatment and treated for 3-6 years in a double-blind fashion. Major outcomes including hospitalization for CHF were recorded during the follow-up.

RESULTS

Of the 4912 included patients, 187 developed CHF during the study. There was no significant difference in the incidence of CHF between the two treatment groups. Using a multivariate analysis, independent risk factors for the occurrence of CHF were age, history of cardiovascular disease, baseline urinary albumin concentration, baseline HbA(1c), and smoking habits. A total of 68 of the 187 patients (36.4%) died during the 12 +/- 11-month period after the first hospitalization for CHF, whereas the annual mortality rate of the population who did not develop CHF was 3.2%.

CONCLUSIONS

Presence of atherosclerotic disease, baseline urinary albumin concentration, and HbA(1c) level were indicators for further development of CHF. Occurrence of CHF is a major prognostic turn in a diabetic patient's life.

Pharmacotherapy of diabetes mellitus: implications for the prevention and treatment of cardiovascular disease

Diabetes mellitus in adults is associated with an increased risk of premature vascular disease and a higher mortality rate. The presence of other risk factors, often seen in diabetic patients, such as systemic hypertension, augments the rate of vascular diseases. Evidence is growing that tight control of hyperglycemia using insulin and/or oral hypoglycemic agents will modify this risk. More aggressive control of concomitant hypertension and/or hyperlipidemia is also required. Diabetic patients who have myocardial infarctions do worse than nondiabetic patients. Various strategies to improve outcomes include the use of tight blood glucose control, and various coronary interventions are currently under clinical study.

Prevalence, awareness, treatment and control of hypertension in a Canarian population. Relationship with glucose tolerance categories. The Guía Study

OBJECTIVE

To estimate the prevalence, awareness, treatment and control of hypertension in a Canarian population; and their relationship with the glucose tolerance categories.

DESIGN

From a population of 6355 subjects over 29 years old, 690 were chosen in a random sampling. Blood pressure measurements, a standard oral glucose tolerance test (excluding known diabetic patients), and a questionnaire on diabetes and hypertension history and medication use was performed.

RESULTS

The total prevalence of hypertension was 50.3%; 62.0% of the hypertensive subjects were aware of their condition; 60.6% had their diastolic and 11.0% their systolic blood pressure controlled and 8.6% had both. For diabetic, glucose intolerant and normoglycemic subjects, the respective prevalences of hypertension were 79.4, 60.2 and 43.1% (higher in diabetic subjects, P < 0.001); the awareness of hypertension was 66.7, 61.8 and 59.5% (differences not significant); systolic blood pressure control was 4.8, 14.7 and 13.7% (lower in diabetic subjects, P = 0.017 versus glucose intolerant and P = 0.011 versus normoglycemic subjects); diastolic blood pressure control was 50.4, 72.1 and 63.2% (lower in diabetic subjects, P = 0.004 versus glucose intolerant and P = 0.025 versus normoglycemic subjects). There were no differences in the number and type of antihypertensive drugs among the different glucose tolerance categories.

CONCLUSIONS

Blood pressure was comparable in our population and in other European populations. The prevalence of hypertension was higher, the awareness was similar, and control was worse in diabetic than in non-diabetic subjects; the drug treatment pattern was not different.

Insulin resistance syndrome and left ventricular mass in healthy young people

BACKGROUND

Findings of atherosclerotic plaques in adolescents, in the context of current epidemics of obesity and type 2 diabetes in youth, demand investigation into early cardiovascular risk development. Left ventricular hypertrophy has been linked to hypertension, obesity, and insulin resistance.

METHODS

Insulin resistance syndrome characteristics (fasting glucose and insulin; systolic blood pressure; waist girth) were measured in 70 normotensive, normoglycemic young people (60% male, 62% black; included 13 twin pairs; age mean +/- SD, 19 +/- 2.6 years). Left ventricular mass indexed by height (2.7) (LVMI) was obtained via ultrasound. Twin pairs were clustered to satisfy the assumption for independent observations.

RESULTS

LVMI was regressed on insulin after controlling for race, gender, and systolic blood pressure. Insulin was a significant (P = 0.02) independent predictor of LVMI (R(2)change = 0.09, P < 0.01). Waist girth accounted for an additional 4% variance of LVMI (P = 0.05). A one-factor model comprising waist (factor loading = 0.83), insulin (0.59), glucose (0.42), and LVMI (0.46) showed good fit [chi2(2) = 0.41, P = 0.81; root-mean-square error of approximation = 0.0].

CONCLUSIONS

A subclinical metabolic syndrome is detectable early in life, before abnormal fasting glucose or high blood pressure appear. Evidence of excessive load on the heart is associated with the metabolic syndrome even after accounting for the effects of race, gender, and blood pressure. Cardiac structure seems as closely associated with this syndrome as fasting glucose level. Based on this evidence, we propose that increased left ventricular mass is a part of insulin resistance syndrome and adds to the need for preventive public health measures to improve health behaviors and cardiovascular risk status in US youth.

Progressive hypertrophy regression with sustained pressure reduction in hypertension: the Losartan Intervention For Endpoint Reduction study

OBJECTIVE

To examine the time course of left ventricular (LV) geometric response to blood pressure (BP) control during 2 years of systematic antihypertensive treatment.

DESIGN

A total of 754 hypertensive patients with left ventricular hypertrophy (LVH) by Cornell voltage-duration product or Sokolow-Lyon voltage criteria on a screening electrocardiogram had their LV mass measured by echocardiogram at enrolment in the Losartan Intervention For Endpoint Reduction (LIFE) trial, and after 12 and 24 months of blinded therapy with losartan-based or atenolol-based regimens.

SETTING

The LIFE trial, in which hypertensive patients with electrocardiographic LVH (Cornell voltage-duration product > 2440 mm x ms and/or Sokolow-Lyon voltage criteria SV1 + RV5-6 > 38 mm) were randomized to >or= 4 years double-blinded treatment with losartan or atenolol.

PARTICIPANTS

A total of 754 LIFE participants with serial echocardiographic measurements of LV geometry.

INTERVENTIONS

None.

MAIN OUTCOME MEASURES

LV wall thicknesses, diameter and mass, and its indices.

RESULTS

Mean systolic/diastolic BP fell from 173/95 to 150/84 mmHg after 1 year (P < 0.001) and to 148/83 mmHg at year 2 (P = not significant). Mean echocardiographic LV mass fell from 233 g at baseline to 206 g after 1 year (P < 0.001, adjusted for change in systolic BP) and to 195 g at year 2 (P < 0.001 versus year 1), with a parallel decrease in indexed LV mass [from 56.1 to 49.7 g/m2.7 (P < 0.001), to 47.1 g/m2.7 (P < 0.001 versus year 1)]. Relative wall thickness decreased from 0.41 at baseline to 0.37 at year 1 (P < 0.001), to 0.36 at year 2 (P < 0.001 versus year 1). As a result, there were serial decreases in prevalences of eccentric LVH [44 to 38%, and to 30% (P < 0.001 versus year 1)] and concentric LVH [24 to 7% (P < 0.001), to 2% (P < 0.05 versus year 1)], and increases in the proportion with normal LV geometry [22 to 50% (P < 0.001), and to 64% (P < 0.01 versus year 1)].

CONCLUSIONS

Sustained BP reduction in hypertensive patients with target organ damage causes continued decrease in echocardiographic LV mass and prevalence of anatomic LVH for at least 2 years despite only small BP decreases after the first year of blinded therapy. These data document cardiac benefit of sustained BP control and suggest that maximum LVH regression with effective antihypertensive treatment requires at least 2 years.

Appetite suppressants and valvular heart disease in a population-based sample: the HyperGEN study

PURPOSE

Previous studies of the association between the use of appetite suppressants and valvular heart disease have not accounted for the effects of valvular structure and aortic root diameter, which are associated with obesity. We assessed whether the use of the appetite suppressants fenfluramine/dexfenfluramine, either alone or with phentermine, was associated with aortic regurgitation while adjusting for these variables.

SUBJECTS AND METHODS

The sample included 2524 adult participants in the population-based Hypertension Genetic Epidemiology Network study. Information regarding current drug use was assessed during a clinical examination. Medication use was continued at the time of echocardiographic study. Expert readers blinded to current therapy read echocardiograms centrally at Cornell Medical Center. Analyses of the associations between use of fenfluramine/dexfenfluramine (alone or with phentermine) and aortic regurgitation adjusted for potential confounders, including aortic root dilatation and valve fibrocalcification.

RESULTS

Nineteen participants, all of whom had hypertension, were being treated with fenfluramine or dexfenfluramine (5 on these agents alone, 14 also with phentermine). Aortic regurgitation was present in 32% (n = 6) of those taking fenfluramine or dexfenfluramine versus 6% (162/2505) of remaining subjects (P = 0.001). In multivariate-adjusted analyses, treatment with fenfluramine or dexfenfluramine was associated with aortic regurgitation (odds ratio [OR] = 4.9; 95% confidence interval [CI]: 1.7 to 14) and aortic fibrocalcification (OR = 5.2; 95% CI: 1.9 to 15).

CONCLUSION

In a population-based sample, use of fenfluramine or dexfenfluramine, alone or in combination with phentermine, was associated with aortic regurgitation independent of aortic dilatation or fibrocalcification.

Fasting plasma glucose is an independent determinant of left ventricular diastolic dysfunction in nondiabetic patients with treated essential hypertension

Left ventricular (LV) hypertrophy and LV diastolic dysfunction are common cardiac changes in hypertensive patients, and these changes are modified by various factors other than blood pressure. The present study was conducted to investigate the influence of mild abnormalities in glucose metabolism on LV structure and function in essential hypertension. In 193 nondiabetic patients with treated essential hypertension, two-dimensional and Doppler echocardiographic examinations were performed, and relative wall thickness (RWT), LV mass index (LVMI), fractional shortening, and the ratio of the peak velocity of atrial filling to early diastolic filling (A/E) were calculated. Fasting plasma glucose (FPG) and HbA1c levels were positively correlated with the A/E ratio and the deceleration time of the E wave. However, these plasma levels had no correlation with RWT, LVMI, or fractional shortening. Peak A wave velocity and the A/E ratio were significantly higher in patients who had FPG of > or = 100 mg/dl (and <126 mg/dl) than those who had FPG of <100 mg/dl, although age, blood pressure, RWT, LVMI, and fractional shortening did not differ between the two groups. In a multiple regression analysis of all subjects, only FPG and age were independent determinants of the A/E ratio. These observations suggest that FPG is a sensitive predictor for LV diastolic dysfunction in nondiabetic patients with treated hypertension. Since a slight increase in plasma glucose levels is associated with abnormalities in diastolic function independent of LV hypertrophy, an early stage of impaired glucose metabolism in hypertensive patients may specifically deteriorate cardiac diastolic function.

Gender difference in diastolic function in hypertension (the HyperGEN study)

Although several studies indicate that there are gender differences in left ventricular (LV) systolic function, it remains unclear whether similar differences exist with regard to diastolic function. Accordingly, Doppler echocardiograms were analyzed in 515 male and 839 female, mostly treated (95%) hypertensive participants enrolled in the Hypertension Genetic Epidemiology Network (HyperGEN) study with no evidence of abnormal wall motion or significant valvular heart disease. There was no difference in age between genders, but after adjusting for age and race, men had lower body mass indexes (29.8 +/- 5.2 vs 32.3 +/- 7.6 kg/m(2)) and heart rates (67 +/- 12 vs 69 +/- 11 beats/min) and higher systolic and diastolic blood pressures (BP) than women (134 +/- 20 vs 130 +/- 21 and 80 +/- 11 vs 72 +/- 11 mm Hg, all p <0.001). LV mass/height(2.7) was slightly greater in women than in men (43 +/- 10 vs 42 +/- 9 g/m(2.7), p <0.05). After adjusting for age, race, systolic BP, body mass index, heart rate, and LV hypertrophy, both mitral E-wave (70 +/- 18 vs 77 +/- 19) and A-wave (74 +/- 15 vs 79 +/- 17, both p <0.001) velocities were lower in men than in women, but the mitral E/A ratio and atrial filling fraction were nearly identical in both genders. Deceleration time (221 +/- 55 vs 214 +/- 46 cm/s, p = 0.018) and isovolumic relaxation time (IVRT) were longer in men than in women (85 +/- 18 vs 81 +/- 17 cm/s, p <0.001). Prolonged IVRT was present in more men than women (14% vs 7%, p <0.05). In analyses of covariance, adjusting for age, race, systolic BP, body mass index, heart rate, and medications, male gender remained related to prolonged deceleration time and IVRT. Thus, in this population-based sample of hypertensive adults, men had evidence of slower early diastolic LV filling than women. This gender difference in diastolic function may provide insight into gender differences in congestive heart failure and other specific cardiovascular diseases.

Cardiovascular morbidity and mortality in patients with diabetes in the Losartan Intervention For Endpoint reduction in hypertension study (LIFE): a randomised trial against atenolol

BACKGROUND

The most suitable antihypertensive drug to reduce the risk of cardiovascular disease in patients with hypertension and diabetes is unclear. In prespecified analyses, we compared the effects of losartan and atenolol on cardiovascular morbidity and mortality in diabetic patients.

METHODS

As part of the LIFE study, in a double-masked, randomised, parallel-group trial, we assigned a group of 1195 patients with diabetes, hypertension, and signs of left-ventricular hypertrophy (LVH) on electrocardiograms losartan-based or atenolol-based treatment. Mean age of patients was 67 years (SD 7) and mean blood pressure 177/96 mm Hg (14/10) after placebo run-in. We followed up patients for at least 4 years (mean 4.7 years [1.1]). We used Cox regression analysis with baseline Framingham risk score and electrocardiogram-LVH as covariates to compare the effects of the drugs on the primary composite endpoint of cardiovascular morbidity and mortality (cardiovascular death, stroke, or myocardial infarction).

FINDINGS

Mean blood pressure fell to 146/79 mm Hg (17/11) in losartan patients and 148/79 mm Hg (19/11) in atenolol patients. The primary endpoint occurred in 103 patients assigned losartan (n=586) and 139 assigned atenolol (n=609); relative risk 0.76 (95% CI 0.58-.98), p=0.031. 38 and 61 patients in the losartan and atenolol groups, respectively, died from cardiovascular disease; 0.63 (0.42-0.95), p=0.028. Mortality from all causes was 63 and 104 in losartan and atenolol groups, respectively; 0.61 (0.45-0.84), p=0.002.

INTERPRETATION

Losartan was more effective than atenolol in reducing cardiovascular morbidity and mortality as well as mortality from all causes in patients with hypertension, diabetes, and LVH. Losartan seems to have benefits beyond blood pressure reduction.

Relations of pulse pressure and other components of blood pressure to preclinical echocardiographic abnormalities

OBJECTIVE

To evaluate the extent to which pulse pressure (PP) is associated with echocardiographic abnormalities, and in particular to whether PP is related to LV hypertrophy taking into account other blood pressure (BP) components.

DESIGN

Cross-sectional.

SETTING

University hospital, hypertension outpatient unit.

PARTICIPANTS

A total of 275 adults (mean age 47 years, range 19-69, 3% aged > or = 65) with essential hypertension. Overt coronary artery disease, valvular disease and secondary hypertension were exclusion criteria. Subjects were divided in two groups with PP < or = 50 or PP > 50 mmHg.

OUTCOME MEASURES

Left ventricular (LV) mass, hypertrophy, LV systolic dysfunction.

RESULTS

Prevalence of LV hypertrophy was higher in subjects with clinic PP > 50 mmHg. Subjects with PP > 50 mmHg had higher clinic and ambulatory systolic than subjects with PP < or = 50 mmHg while diastolic BP did not differ between groups. PP and systolic BP, either clinic or ambulatory, showed similar correlation to LV hypertrophy in separate logistic multivariate models. Using different methodologies, PP was not related to LV mass index or hypertrophy when the effect of its component systolic BP was taken into account. In separate analyses, PP was not significantly related to ejection fraction or midwall mechanics.

CONCLUSION

Middle-aged clinically healthy hypertensives with PP > 50 mmHg had two-fold higher prevalence of LV hypertrophy than those with PP < or = 50 mmHg, which may contribute to the higher cardiovascular risk in subjects with higher PP. However, in our sample, PP was not related to LV hypertrophy independently of systolic BP, suggesting that systolic BP is the explanatory link of the relation between PP and LV hypertrophy.

Correlates of pulse pressure reduction during antihypertensive treatment (losartan or atenolol) in hypertensive patients with electrocardiographic left ventricular hypertrophy (the LIFE study)

In hypertensive patients, pulse pressure has been related to hypertension-induced target organ damage and risk of cardiovascular events. However, correlates of pulse pressure reduction during antihypertensive treatment have been less extensively investigated. We related pulse pressure changes to clinical and echocardiographic findings before and after 2 years of antihypertensive treatment in 767 patients aged 55 to 80 years (mean 66) in the Losartan Intervention For End point reduction in hypertension study. Over 2 years, blood pressure and pulse pressure were reduced from 173/98 to 147/84 mm Hg and from 75 to 63 mm Hg, respectively, both p <0.001. In linear multivariate analysis controlling for initial pulse pressure, 2-year reduction in pulse pressure correlated negatively with age and concomitant diabetes mellitus, and positively with body height and 2-year reduction in mean blood pressure (multiple R(2) = 0.42, p <0.01). When dividing the study population into 2 groups using a prognostically validated partition for pulse pressure, patients with pulse pressure > or =63 mm Hg after 2 years of antihypertensive treatment (n = 349) were older and shorter, included more women and patients with isolated systolic hypertension, diabetes mellitus, albuminuria, and echocardiographic left ventricular hypertrophy at baseline, and also had a smaller decrease in mean blood pressure and the urinary albumin/creatinine ratio over 2 years (all p <0.05). Thus, in hypertensive patients with electrocardiographic left ventricular hypertrophy, older age, less reduction in mean blood pressure, concomitant diabetes mellitus, and shorter stature are associated with attenuated pulse pressure reduction during antihypertensive treatment.

Left ventricular mass and systolic dysfunction in essential hypertension

A relation between left ventricular (LV) hypertrophy and depressed midwall systolic function has been described in hypertensive subjects. However, a strong confounding factor in this relation is concentric geometry, which is both a powerful determinant of depressed midwall systolic function and a correlate of LV mass in hypertension. To evaluate the independent contribution of LV mass to depressed systolic function, 1827 patients with never-treated essential hypertension (age 48 +/- 12 years, men 58%) underwent M-mode echocardiography under two-dimensional guidance. Relative wall thickness was the strongest determinant of low midwall fractional shortening (r = -0.63, P < 0.0001). The significant inverse relation observed between LV mass and midwall fractional shortening (r = -0.43, P < 0.0001) persisted after taking into account the effect of relative wall thickness (partial r = -0.27, P < 0.0001). Within each sex-specific quintile of relative wall thickness, prevalence of subnormal afterload-corrected midwall systolic function was greater in subjects with, than in subjects without, LV hypertrophy (P < 0.05 for the first, third, fourth and fifth quintile). In a multiple linear regression analysis, both LV mass (P < 0.0001) and relative wall thickness (P < 0.0001) were independent predictors of a reduced midwall fractional shortening. In conclusion, the inverse association between LV mass and midwall systolic function is partly independent from the effect of relative wall thickness. LV hypertrophy is a determinant of subclinical LV dysfunction independently of the concomitant changes in chamber geometry.

Association of left ventricular hypertrophy with metabolic risk factors: the HyperGEN study

OBJECTIVE

To determine whether combinations of metabolic risk factors (obesity, diabetes and hypercholesterolemia) influence the magnitude of left ventricular (LV) mass and prevalence of LV hypertrophy.

DESIGN

Cross-sectional, relational.

METHODS

A total of 1627 hypertensive (85.9% treated, 1036 women, 1041 African Americans) and 342 normotensive (180 women, 183 African Americans) participants in the Hypertension Genetic Epidemiology Network (HyperGEN) Study, without prevalent cardiovascular disease, were studied. Echocardiographic LV mass, normalized by height(2.7) or fat-free mass or body surface area (BSA) and the ratio of stroke volume to pulse pressure as a percentage of predicted (as a crude estimate of arterial compliance) were analyzed in relation to obesity [by body mass index (BMI)], central fat distribution (by waist circumference), diabetes (by ADA criteria) and hypercholesterolemia.

RESULTS

Obesity, hypercholesterolemia, and diabetes were more frequent among hypertensives than normotensives (all P < 0.001). After controlling for age, sex, race and type and combination of antihypertensive medication, LV mass/height(2.7), but not LV mass/fat-free mass and LV mass/BSA, increased with the number of metabolic risk factors, both in normotensive and hypertensive participants, also after further adjustment for blood pressure (all P < 0.001). Stroke volume/pulse pressure also decreased in hypertensive, but much less in normotensive subjects, with increasing number of metabolic risk factors, independently of relevant confounders (P < 0.0001). Prevalence of LV hypertrophy was predicted by older age, hypertension, central fat distribution, black race and independently increased with the number of associated metabolic risk factors (P < 0.0001).

CONCLUSIONS

The progressive addition of metabolic risk factors including central obesity, diabetes and hypercholesterolemia is associated with higher LV mass normalized by height(2.7), independently of hypertension and other important biological covariates. Obesity played a major role in this association. This finding indicates that LV mass is a potentially useful bioassay of strategies of global cardiovascular prevention.

Cardiomyopathy and heart failure in diabetes

Patients with insulin resistance or type 2 diabetes have a particularly high risk for heart failure and a poor prognosis once they develop heart failure. The choice of drugs for the management of heart failure in these patients should be directed at changing the natural history of the disease. The various drugs available for the treatment of heart failure, including ACE inhibitors and beta-adrenergic blockers, are known to be beneficial and should be given as first-line agents. Aggressive risk-factor modification and tight blood pressure and glycemic control are crucial. Much work is needed to establish the safety and efficacy of various oral antidiabetic agents, especially the TZDs, for which the theoretic benefits are substantial and overall morbidity and mortality impact remain ill-defined.

Separate and joint effects of systemic hypertension and diabetes mellitus on left ventricular structure and function in American Indians (the Strong Heart Study)

Although the association of systemic hypertension (SH) with diabetes mellitus (DM) is well established, the cardiac features and hemodynamic profile of patients with SH and DM diagnosed by American Diabetes Association criteria have not been elucidated. To address this issue, echocardiograms were analyzed in 1,025 American Indian participants of the Strong Heart Study with neither DM nor SH, 642 with DM alone, 614 with SH alone, and 874 with SH and DM. In analyses that adjusted for age, gender, body mass index, and heart rate, DM and SH were associated with increased left ventricular (LV) wall thicknesses, with the greatest impact of DM on LV relative wall thickness and of the combination of DM and SH on LV mass (both p <0.001). LV fractional shortening was reduced with SH and SH + DM, midwall shortening was reduced with DM, SH, and their combination, and was reduced in both diabetic groups compared with their nondiabetic counterparts (p <0.001). DM alone was associated with lower measures of LV pump performance (stroke volume, cardiac output, and their indexes) than SH alone. Pulse pressure/stroke index, an indirect measure of arterial stiffness, was elevated in participants with DM or SH alone and most in those with both conditions. There were progressive increases from the reference group to DM alone, SH alone, and DM + SH with regard to prevalences of LV hypertrophy (12% to 19%, 29% and 38%) and subnormal LV myocardial function (7% to 10%, 11% and 18%, both p <0.001). In conclusion, DM and SH each have adverse effects on LV geometry and function, and the combination of SH and DM results in the greatest degree of LV hypertrophy, myocardial dysfunction, and arterial stiffness.