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

Pre-clinical diabetic cardiomyopathy: prevalence, screening, and outcome

AIMS

Diabetic cardiomyopathy, characterized by left ventricular (LV) dysfunction and LV hypertrophy independent of myocardial ischaemia and hypertension, could contribute to the increased life-time risk of congestive heart failure seen in patients with diabetes. We assessed prospectively the prevalence, effectiveness of screening methods [brain natriuretic peptide (BNP) and C-reactive protein in combination with clinical parameters], and outcome of pre-clinical diabetic cardiomyopathy.

METHODS AND RESULTS

We studied 100 adults (mean age 57.4 +/- 10.2 years, 44% females) with diabetes and no previous evidence of structural heart disease. By echocardiography, diabetic cardiomyopathy was present in 48% of patients. Screening with combinations of clinical parameters (gender, systolic blood pressure, and body mass index), but not BNP, resulted in high negative predictive values for diabetic cardiomyopathy. During a mean follow-up of 48.5 +/- 9.0 months, in the groups with and without diabetic cardiomyopathy, 12.5 vs. 3.9% (P < 0.2) patients died or experienced cardiovascular events and 37.5 vs. 9.6% (P < 0.002) had a deterioration in NYHA functional class. Overall event-free survival was 54 vs. 87% (P = 0.001) in the groups with and without diabetic cardiomyopathy, respectively. Brain natriuretic peptide was an independent predictor of events [odds ratio 3.5 (1.1-10.9), P = 0.02].

CONCLUSION

Pre-clinical diabetic cardiomyopathy is common. Screening with combinations of simple clinical parameters, but not BNP, can be useful to identify those patients needing further evaluation. Patients with pre-clinical diabetic cardiomyopathy are at increased risk for functional deterioration and possibly cardiovascular events during follow-up. Brain natriuretic peptide was shown to be an independent predictor of future events.

Impaired flow-mediated vasodilatation is associated with increased left ventricular mass in a multiethnic population. The Northern Manhattan Study

BACKGROUND

Increased left ventricular (LV) mass and endothelial dysfunction are important risk factors for cardiovascular mortality and morbidity. However, it is not clear whether endothelial dysfunction is associated with increased LV mass. We tested the hypothesis that impaired flow-mediated vasodilatation (FMD) is associated with increased LV mass in a population-based multiethnic cohort.

METHODS

As a part of the Northern Manhattan Study (NOMAS), we performed two-dimensional echocardiography and FMD assessment during reactive hyperemia by high-resolution ultrasonography in 867 stroke-free community participants. LV mass was calculated according to an established method. LV hypertrophy was defined as the 90th percentile of sex-specific LV mass indexed for body surface area among normal subjects. Multivariable models were used to test the association of FMD with LV mass.

RESULTS

In multiple linear regression analysis adjusting for age, sex, body mass index, systolic blood pressure, antihypertensive medications, low-density lipoprotein cholesterol, diabetes, smoking, hematocrit, and race-ethnicity, FMD was inversely associated with LV mass (beta = -1.21 +/- 0.56, P = 0.03). The association persisted after further adjustment for any component of blood pressure (systolic, mean, and pulse pressure). In univariate logistic regression analysis, each 1% decrease in FMD was associated with an 8% higher risk of LV hypertrophy (odds ratio 1.08, 95% confidence interval 1.03-1.13 per each FMD point P < 0.01).

CONCLUSIONS

Impaired FMD is associated with LV mass, independent of other factors associated with increased LV mass. Endothelial dysfunction might be a potential risk factor for LV hypertrophy.

Prevalence of non-diabetic renal disease in patients with type 2 diabetes

It is important to differentiate proteinuria from non-diabetic renal diseases (NDRD) or diabetic nephropathy in diabetic patients. The purpose of our study was to evaluate the prevalence of NDRD. A retrospective analysis was performed on diabetic patients who had undergone renal biopsy during a 6-year period. Our study revealed a high prevalence of NDRD in the diabetic population. Sixty-nine patients were investigated, 52.2% were diagnosed as NDRD and 47.8% as DN. Focal segmental glomerulosclerosis was the most common lesion found in patients with NDRD. We found a relationship between DN and fasting blood glucose level, systolic blood pressure, diastolic blood pressure, LVMI, intima-media thickening (IMT), and the presence of carotid plaques. Patients with NDRD had a lower incidence of diabetic retinopathy (DR). The absence of DR to differentiate NDRD had a sensitivity of 72.7%, a specificity 91.7%, and an ROC=0.822. Fasting blood glucose level had a sensitivity and specificity of 93.9% and 75%, respectively. Similarly, the use of IMT had sensitivity and specificity of 90% and 75.8%, respectively. In this study, we determined that the absence of DR, a lower fasting blood glucose level, and IMT is useful in differentiating NDRD from DN in diabetic patients with overt proteinuria.

Safety and feasibility of achieving lower systolic blood pressure goals in persons with type 2 diabetes: the SANDS trial

The Stop Atherosclerosis in Native Diabetics Study (SANDS) was a randomized open-label clinical trial in type 2 diabetics designed to examine the effects of intensive reduction of blood pressure, aggressive vs standard goals (< or =115/75 mm Hg vs < or =130/80 mm Hg), and low-density lipoprotein (LDL) cholesterol on the composite outcome of change in carotid intimal-medial thickness and cardiovascular events. The study demonstrated that in conjunction with a lower LDL cholesterol target of 70 mg/dL, aggressive systolic blood pressure-lowering resulted in a reduction in carotid intimal-medial thickness and left ventricular mass without measurable differences in cardiovascular events. The blood pressure treatment algorithm included renin-angiotensin system blockade, with other agents added if necessary. The authors conclude that both standard and more aggressive systolic blood pressure reduction can be achieved with excellent safety and good tolerability in patients with type 2 diabetes mellitus.

Increased urinary orosomucoid excretion: a proposed marker for inflammation and endothelial dysfunction in patients with type 2 diabetes

OBJECTIVE

In a previous study, urinary orosomucoid excretion rate (UOER) independently predicted cardiovascular mortality in patients with type 2 diabetes. The aim of the present study was to determine whether increased UOER is associated with cardiovascular risk factors such as inflammation, impaired left ventricular function and endothelial dysfunction in patients with type 2 diabetes.

MATERIAL AND METHODS

We performed a cross-sectional study of 41 patients with type 2 diabetes (17 patients with normal UOER and 24 with increased UOER) with no history of cardiovascular disease and 21 healthy controls. Urinary orosomucoid was measured using a particle-enhanced immunoturbidimetric assay. Plasma interleukin-6 (IL-6), tissue plasminogen activator (tPA) and soluble intercellular adhesion molecule-1 (sICAM) were measured using ELISA. Endothelial function measured as vasodilatory capacity of the brachial artery and echocardiography were done in all participants.

RESULTS

Patients with diabetes and increased UOER had subclinically increased serum orosomucoid (p<0.001), C-reactive protein (CRP) (p<0.001), IL-6 (p<0.001), tPA (p<0.003) and sICAM (p<0.003) compared with healthy controls. In patients with type 2 diabetes, UOER was independently associated with increasing values of IL-6 (1.43 (1.06-1.93)) and tPA (1.82 (1.20-2.77)). Measurements by echocardiography showed no signs of cardiac dysfunction.

CONCLUSIONS

Asymptomatic patients with type 2 diabetes and increased UOER displayed signs of chronic low-grade inflammation and endothelial dysfunction. UOER was independently related to markers of proinflammation and endothelial dysfunction in patients with type 2 diabetes. The previously shown relation between increased UOER and cardiovascular mortality is proposed to be caused by chronic low-grade inflammation and early endothelial dysfunction.

Inflammatory activation and left ventricular mass in essential hypertension

BACKGROUND

Inflammation is an independent risk factor for high blood pressure, and as a consequence inflammatory cytokines could be related with left ventricular hypertrophy (LVH). We sought to assess the association and predictive role of different cytokine levels with LVH in a group of patients with essential hypertension (HT).

METHODS

We studied 251 asymptomatic hypertensive patients (142 with LVH and 109 without LVH), referred from 11 hospitals. A routine physical examination, laboratory analyses, and echo-Doppler study were performed. Plasma soluble tumor necrosis factor (TNF) receptors (sTNF-R1 and sTNF-R2), interleukin-6 (IL-6), and interleukin-1 receptor antagonist (IL-1ra) were centrally determined.

RESULTS

Hypertensive patients with LVH had higher inflammatory cytokine levels than the group without hypertrophy (P < 0.001). Multivariate linear regression reported that sTNF-R1 (P < 0.01) was an independent predictor of left ventricular mass index (LVMI). All cytokines had significant area under the curves for detection of LVH, but sTNF-R1 has the highest area, 0.71 +/- 0.03 (P < 0.001). Finally, prevalence of LVH was increased in the group of patients with higher cytokine levels, and logistic regression analysis showed that sTNF-R1 (odds ratio = 2.59, 95% CI of 1.14-5.87) was an independent predictor of LVH.

CONCLUSIONS

Cytokine levels were significantly correlated with LVMI in hypertensive patients. The sTNF-R1 was an independent predictor of LVMI. Plasma sTNF-R1 concentrations could be a predictive factor of LVH in patients with essential HT.

Cardiac allograft remodeling after heart transplantation is associated with increased graft vasculopathy and mortality

The aim of this study was to assess the patterns, predictors and outcomes of left ventricular remodeling after heart transplantation (HTX). Routine echocardiographic studies were performed and analyzed at 1 week, 1 year and 3-5 years after HTX in 134 recipients. At each study point the total cohort was divided into three subgroups based on determination of left ventricle mass and relative wall thickness: (1) NG-normal geometry (2) CR-concentric remodeling and (3) CH-concentric hypertrophy. Abnormal left ventricular geometry was found as early as 1 week after HTX in 85% of patients. Explosive mode of donor brain death was the most significant determinant of CH (OR 2.9, p = 0.01) at 1 week. CH at 1 week (OR 2.72, p = 0.01), increased body mass index (OR 1.1, p = 0.01) and cytomegalovirus viremia (OR - 4.06, p = 0.02) were predictors of CH at 1 year. CH of the cardiac allograft at 1 year was associated with increased mortality as compared to NG (RR 1.87, p = 0.03). CR (RR 1.73, p = 0.027) and CH (RR 2.04, p = 0.008) of the cardiac allograft at 1 year is associated with increased subsequent graft arteriosclerosis as compared to NG.

Association between diabetes mellitus and left ventricular hypertrophy in a multiethnic population

It is still controversial whether type 2 diabetes mellitus (T2DM) is associated with increased left ventricular (LV) mass independent of body size. We tested the hypothesis that T2DM is independently associated with LV mass in a multiethnic cohort. In the Northern Manhattan Study (NOMAS) cohort sample, a total of 1,932 subjects (67.9+/-9.6 years, 769 men and 1,163 women, 443 with DM and 1,489 without DM) were studied by transthoracic echocardiography, and LV mass was calculated. LV hypertrophy was defined as the upper quartile of LV mass. Multivariable models were used to assess the association of T2DM with LV mass after adjusting for age, gender, race, body mass index (BMI), systolic blood pressure, education, history of coronary artery disease, physical activity, and alcohol consumption. LV mass (189+/-60 vs 174+/-59 g, p<0.0001), BMI, and systolic blood pressure were higher in the DM group than in the non-DM group, whereas age and gender distributions were similar between groups. In multivariable analysis, T2DM was independently associated with increased LV mass (p=0.03). Presence of T2DM was associated with increased risk of LV hypertrophy (adjusted odds ratio 1.46, 95% confidence interval 1.13 to 1.88, p=0.004). Although no interactions were observed between T2DM and BMI on LV hypertrophy (p=0.6), there was a significant interaction between T2DM and waist circumference on LV hypertrophy (p=0.01). In conclusion, T2DM was independently associated with increased LV hypertrophy independent of various covariates in this multiethnic sample. Presence of T2DM increased the risk of LV hypertrophy by about 1.5-fold, and it possibly interacted with central obesity.

Relation of left ventricular hypertrophy with systemic inflammation and endothelial damage in resistant hypertension

The relation between left ventricular hypertrophy (LVH) and unfavorable cardiovascular prognosis may involve systemic inflammation and endothelial dysfunction/damage. The aim of this study was to investigate in a cross-sectional design the relationships of LVH with C-reactive protein (CRP) levels (a marker of systemic low-grade inflammation) and with microalbuminuria (a marker of glomerular endothelial damage) in 705 patients with resistant hypertension. At baseline, all were submitted to a laboratory evaluation including 24-hour urinary albumin excretion, 2D echocardiogram, and 24-hour ambulatory blood pressure monitoring. A total of 463 patients also had high-sensitivity CRP levels determined. LVH was defined as an indexed left ventricular mass >110 g/m(2) in women and >125 g/m(2) in men. Microalbuminuria was evaluated in 3 categories: low normal (<15 mg/24 hours), high normal (between 15 and 29 mg/24 hours), and abnormal (between 30 and 299 mg/24 hours). CRP was dichotomized at the median value (3.7 mg/L). Associations with LVH were examined after adjustment for all of the potential confounders by multivariate logistic regression. A total of 534 patients (75.7%) had LVH. After full adjustment, both abnormal microalbuminuria (odds ratio: 1.97; 95% CI: 1.04 to 3.73) and high CRP (OR: 1.76; 95% CI: 1.06 to 2.93) were independently associated with LVH occurrence. The high-normal albuminuria was associated with a borderline significant 46% increased chance of having LVH. Furthermore, the association between high CRP and LVH was observed exclusively in the subgroup with normal albuminuria. In conclusion, both systemic inflammation and endothelial damage were associated with LVH occurrence. These relationships offer insight into the pathophysiological mechanisms linking LVH to atherosclerosis and to increased cardiovascular morbidity and mortality.

Prognostic implications of relations of left ventricular systolic dysfunction with body composition and myocardial energy expenditure: the Strong Heart Study

OBJECTIVE

We sought to investigate prognostic implications of the relationships of estimated left ventricular (LV) myocardial energy expenditure (MEE) with LV systolic dysfunction, body composition, and inflammation in a population-based sample of adults without overt congestive heart failure.

METHODS

Echocardiography was used to assess LV ejection fraction (EF) and MEE. Body composition was evaluated by bioelectric impedance. Dietary recall was used to assess 24-hour calorie intake. Participants in the Strong Heart Study without prior congestive heart failure and with all needed data available (n = 3087) were divided based on LV EF (>55%, 54%-45%, or <45%).

RESULTS

Participants with EF less than 45% were older and they had lower body mass index, adipose mass, fat-free mass, and 24-hour calorie intake than participants with normal EF (>/=55%), and had greatest reductions of body mass index and physical activity in a time interval of 3.5 years, on average, elapsed between an initial clinical assessment and the evaluation at the time of the echocardiographic examination (P < .01). Lower EF was associated with male sex, hypertension, diabetes, coronary heart disease, and higher fibrinogen, C-reactive protein, and plasma creatinine levels (all P < .01). MEE was higher with lower EF (all P < .001). In Cox regression models, during approximately 8 years of observation, MEE comprised between 97 and 123 cal/min and MEE greater than 123 cal/min were associated with 2.5-fold and additional 3.3-fold higher rates of cardiac death, respectively, compared with MEE less than 97 cal/min, independently of EF, body composition, and other covariates. However, lower adipose mass predicted increased risk of cardiac death independent of MEE and EF.

CONCLUSION

In a population-based sample of adults including ambulatory individuals with depressed LV systolic function but without overt congestive heart failure, depressed EF was associated independently with higher MEE, lower adipose mass, and higher fibrinogen. However, increased MEE and lower adipose mass predicted cardiac death independently of EF and other covariates.

Differential impact of left ventricular mass and relative wall thickness on cardiovascular prognosis in diabetic and nondiabetic hypertensive subjects

BACKGROUND

Cardiovascular prognostic significance of relative wall thickness (RWT) in patients with diabetes has not been reported although concentric hypertrophy is common in diabetic patients.

PURPOSE

This study was conducted to test the hypothesis that the prognostic significance of different measures of left ventricular (LV) geometric change, principally LV mass index (LVMI) and RWT, would be different in diabetic patients compared with nondiabetic individuals among Japanese hypertensive subjects.

METHODS

Ambulatory blood pressure monitoring and echocardiography were performed in 400 uncomplicated hypertensive individuals at baseline, of whom 379 (157 with diabetes and 222 without diabetes; mean age 67.8 +/- 8.8 years) were successfully followed up for 63 +/- 26 months to document cardiovascular events. We dichotomized LVMI and RWT to the highest quartile vs other 3 quartiles for further categoric analyses in diabetic and nondiabetic patients.

RESULTS

Fifty-three cardiovascular events occurred during the follow-up period. With Kaplan-Meier analysis, both diabetic and nondiabetic patients with the highest quartile of LVMI showed a significantly higher incidence of cardiovascular vents. However, the highest quartile of RWT was associated with cardiovascular events only in diabetic subjects. With Cox regression analyses controlling for age, sex, body mass index, serum creatinine, triglycerides, and clinic systolic blood pressure, RWT (per 0.01 change), but not LVMI, was associated with cardiovascular events in diabetic patients (relative risk: 1.06, 95% confidence interval 1.02-1.11; P = .008), whereas LVMI (g/m2), but not RWT, was associated with cardiovascular events in nondiabetic patients (relative risk: 1.02, 95% confidence interval 1.01-1.03; P = .005).

CONCLUSION

In hypertensive subjects with type 2 diabetes mellitus, echocardiographic LV RWT is a predictor of cardiovascular events independent of LV mass and other confounders.

Plasma Osteoprotegerin Levels in the General Population

Osteoprotegerin, a member of the tumor necrosis factor receptor superfamily, has pleiotropic effects on bone metabolism, endocrine function, and the immune system. Myocardial expression and circulating levels of osteoprotegerin are increased in heart failure. The relationship between osteoprotegerin levels in the general population and indices of left ventricular structure and function is unknown. Plasma osteoprotegerin levels and cardiac MRI indices of left ventricular structure and function were available in 2715 subjects (median age: 44 years; 45% male) enrolled in the Dallas Heart Study. The associations between osteoprotegerin concentration and indices of left ventricular structure and function were assessed by linear regression analysis, adjusting for possible confounders. By gender-specific linear regression analysis, higher osteoprotegerin levels were significantly associated with higher left ventricular mass, left ventricular wall thickness, left ventricular concentricity index, and lower left ventricular ejection fraction (P<0.001 for all). After adjustment for age, race, fat-free mass, fat mass, hypertension, diabetes, coronary artery disease, estimated glomerular filtration rate, hypercholesterolemia, smoking status, hormone replacement therapy, coronary artery calcium score >10, and presence of aortic plaque, osteoprotegerin remained significantly associated with each of these left ventricular indices among male subjects (P<0.05 for each). Among female subjects, higher osteoprotegerin was independently associated with higher left ventricular end-systolic volume and lower ejection fraction (P<0.0001 for each) but not with indices of left ventricular hypertrophy. These findings are compatible with the theory that osteoprotegerin may play a pathophysiological role in the development of left ventricular hypertrophy and systolic dysfunction.

Association of low-grade urinary albumin excretion with left ventricular hypertrophy in the general population: the MONICA/KORA Augsburg Echocardiographic Substudy

BACKGROUND

Even mild renal dysfunction is a predictor of cardiovascular morbidity. We investigated whether sub-threshold microalbuminuria or mildly decreased estimated glomerular filtration rate (eGFR) are related to left ventricular hypertrophy (LVH) in the general population.

METHODS

Urinary albumin-to-creatinine ratio (UACR) served to determine albuminuria, eGFR was estimated using modification of diet in renal disease (MDRD) formula, and LV geometry was assessed echocardiographically in the third MONItoring of trends and determinants in CArdiovascular disease/Cooperative Health Research in the Augsburg Area (MONICA/KORA) Augsburg survey (n = 1187).

RESULTS

The prevalence of LVH increased in parallel with UACR. Compared with the first tertile of this normal population, the age, systolic blood pressure (SBP), body mass index, gender and diabetes adjusted odds ratio (OR) for LVH was elevated already in the second (4.32-8.75 mg/g in men; 4.60-9.48 mg/g in women; OR: 2.10, P = 0.001) as well as in the third UACR-tertile (> or =8.76 mg/g in men; > or =9.49 mg/g in women; OR: 1.63, P = 0.035). Likewise, adjusted SBP increased with UACR-tertiles [129 vs 132 (P = 0.036) and 137 mmHg (P < 0.001) in the first, second and third tertile, respectively], whereas diastolic blood pressure was significantly elevated only in the third UACR-tertile [79 vs 80 and 81 mmHg (P = 0.002) in the tertiles, respectively]. In contrast, tertiles of eGFR or mildly impaired eGFR (<90 ml/min/1.73 m(2)) were not associated with the prevalence of LVH in multivariate models.

CONCLUSIONS

At the general population level, even low-grade albuminuria is associated with LVH. Thus, the conventional UACR-threshold of microalbuminuria (30 mg/g) may be too conservative given that end organ damage such as LVH is observed with increased frequency at much lower levels.

High-sensitivity C-reactive protein is only weakly related to cardiovascular damage after adjustment for traditional cardiovascular risk factors

BACKGROUND

The independent prognostic value of high-sensitivity C-reactive protein (hsCRP) has been questioned, and consequently we decided to investigate whether hsCRP was associated with subclinical cardiovascular (CV) damage independently of traditional CV risk factors.

METHODS

In a population-based sample of 2028 apparently healthy individuals without prior stroke or myocardial infarction not receiving any CV, anti-diabetic or lipid-lowering treatment, aged 41, 51, 61 or 71 years, we measured in 1993 serum hsCRP, traditional CV risk factors (lifestyle, metabolic and hemodynamic) and assessed subclinical CV damage [atherosclerotic plaques in the carotid arteries, pulse wave velocity (PWV), urine albumin/creatinine ratio (UACR), left ventricular (LV) mass and ejection fraction].

RESULTS

Adjusting for age and gender in multiple regression analyses, higher log(hsCRP) was associated with higher logPWV (beta = 0.15) and log(left ventricular mass index) (LVMI) (beta = 0.09, both P < 0.001), LV relative wall thickness (beta = 0.07, P < 0.01), logUACR (beta = 0.04, P = 0.06) and more atherosclerotic plaques (beta = 0.06, P < 0.05). However, higher log(hsCRP) was only weakly associated with higher logPWV(beta = 0.06, P < 0.05) and more atherosclerotic plaques (beta = 0.04, P = 0.06) when adjusting for other significant CV risk factors, such as daily smoking (beta = 0.18), female gender (beta = -0.17), older age (beta = 0.11), lower log(high density lipoprotein cholesterol) (beta = -0.11, all P < 0.001); wider waist (beta = 0.17), higher body mass index (beta = 0.14), higher heart rate (beta = 0.06, all P < 0.01); and higher log(plasma glucose) (beta = 0.05, P < 0.05) (adj. R2 = 0.19, P < 0.001).

CONCLUSION

After adjustment for traditional CV risk factors hsCRP was only associated with PWV and atherosclerotic plaques, indicating a possible effect of low-grade inflammation on macrovascular damage. The close relationship between traditional CV risk factors and hsCRP suggested that hsCRP was an integrated CV risk marker early in the development of atherosclerosis.

Optimized Heart Failure Therapy and Complete Anemia Correction on Left-Ventricular Hypertrophy in Nondiabetic and Diabetic Patients Undergoing Hemodialysis

BACKGROUND

According to new guidelines, diabetes mellitus per se can be considered as stage I chronic heart failure (CHF). Available evidence suggests that patients suffering from both diabetes mellitus and renal insufficiency have disproportionately high rates of left-ventricular hypertrophy (LVH).

METHODS

Optimized heart failure therapy, including beta-blockers, ACE-inhibitors and AT II-type-1-receptor-blockers, was prescribed in combination with complete anemia correction using epoetin beta (target hemoglobin: 13.5 g/dl for women; 14.5 g/dl for men) to 230 patients (55% male) with ambulatory hemodialysis, including 60 patients (52% male) with diabetes. Echocardiographic follow-up examinations were performed over a mean period of 4.4 +/- 1.2 years.

RESULTS

Mean hemoglobin levels at the study end significantly increased to target levels in the entire study population and in patients with diabetes (both p < 0.001). Compared with baseline, significant improvements were seen in hemodialysis patients - both without and with diabetes - in left-ventricular mass index (-28.8 g/m2 [p < 0.001] and 29.0 g/m2 [p < 0.005], respectively), left-ventricular ejection fraction (+7.0% [p < 0.001] and +8.3% [p < 0.01], respectively) and in NYHA class (-0.84 [p < 0.01] and -1.12 [p < 0.01], respectively). Similar to the results in the overall population, a highly significant reduction in LVH (p < 0.005) and significant improvements in LVEF (p < 0.01) and NYHA class (p < 0.01) were seen in the high-risk subgroup of diabetic patients.

CONCLUSIONS

Patients undergoing hemodialysis, with or without concomitant diabetes, benefit considerably from optimized, multifactorial heart failure therapy combined with complete anemia correction.

QT dispersion: comparison between participants with Type 1 and 2 diabetes and association with microalbuminuria in diabetes

BACKGROUND AND AIMS

The interlead variation of QT duration in surface electrocardiogram [ECG; QT dispersion (QTd)] has been shown to predict mortality in both diabetic and general population. Diabetic cardiac autonomic neuropathy (CAN) is a common complication of diabetes, and it is also associated with worse prognosis among the diabetic population. In this study, we investigated the association between QTd duration and CAN, as well as other complications of diabetes in participants with Types 1 and 2 diabetes.

METHODS

A total of 184 patients with either Type 1 (n=63) or 2 (n=121) diabetes, as well as 100 control participants, matched for age and sex with the diabetic individuals, were studied. QT and RR intervals were measured on 12 leads of resting ECG tracing. QTd was calculated semiautomatically using a computer program as the difference between the maximum and the minimum QT in any of the 12 leads. CAN was diagnosed when two out of the four classical tests were abnormal.

RESULTS

QTd was not significantly different between controls and patients with either Type 1 or 2 diabetes. Age-adjusted QTd intervals were not significantly different between patients with Types 1 and 2 diabetes (P=.86). For both types of diabetes, no significant differences were found in QTd between patients with and without CAN. Multivariable linear regression analysis, after adjustment for a number of confounding factors, demonstrated a positive association between QTd and duration of diabetes (P=.02) in the group of the patients with Type 1 diabetes. In those with Type 2 diabetes, QTd was associated with age (P=.006) and presence of microalbuminuria (P=.001). In addition, no significant association was found with retinopathy or blood pressure levels.

CONCLUSIONS

Age-adjusted QTd interval was not different between patients with Types 1 and 2 diabetes. CAN is not associated with QTd interval in both types of diabetes. Furthermore, microalbuminuria was found to be the strongest predictor of QTd in patients with Type 2 diabetes. Because long QTd interval predicts cardiac mortality in participants with diabetes, it is suggested that it may be a useful adjuvant index in the evaluation of cardiovascular risk in participants with Type 2 diabetes and microalbuminuria.

Coronary heart disease risk equivalence in diabetes depends on concomitant risk factors

OBJECTIVE

Diabetes has been defined as a coronary heart disease (CHD) risk equivalent, and more aggressive treatment goals have been proposed for diabetic patients.

RESEARCH DESIGN AND METHODS

We studied the influence of single and multiple risk factors on the 10-year cumulative incidence of fatal and nonfatal CHD and cardiovascular disease (CVD) in diabetic and nondiabetic men and women, with and without baseline CHD or CVD, in a population (n = 4,549) with a high prevalence of diabetes.

RESULTS

In both sexes, diabetes increased the risk for CHD (hazard ratio 1.99 and 2.93 for men and women, respectively). Diabetic men and women had a 10-year cumulative incidence of CHD of 25.9 and 19.1%, respectively, compared with 57.4 and 58.4% for nondiabetic men and women with previous CHD. The pattern was similar when only fatal events were considered. Diabetic individuals with one or two risk factors had a 10-year cumulative incidence of CHD that was only 1.4 times higher than that of nondiabetic individuals (14%). However, the 10-year incidence of CHD in diabetic subjects with multiple risk factors was >40%, and the incidence of fatal CHD was higher in these subjects than in nondiabetic subjects with previous CHD. Data for CVD showed similar patterns, as did separate analyses by sex.

CONCLUSIONS

Our results and comparisons with other available data show wide variation in the rate of CHD in diabetes, depending on the population and existing risk factors. Most individuals had a 10-year cumulative incidence >20%, but only those with multiple risk factors had a 10-year cumulative incidence that was equivalent to that of patients with CHD. Until more data are available, it may be prudent to consider targets based on the entire risk factor profile rather than just the presence of diabetes.

What does minor elevation of C-reactive protein signify?

Reports of the predictive value of minor elevation of serum C-reactive protein (CRP) levels (between 3 and 10 mg/L) for atherosclerotic events have generated considerable interest, as well as a degree of controversy and confusion. CRP concentrations in this range are found in about one third of the American population. To better understand the mechanisms underlying minor elevation of CRP, we have surveyed its reported associations with a variety of states and conditions. It has become clear that even minimal environmental irritants and inflammatory stimuli elicit a minor CRP response. Minor CRP elevation has been found associated with a number of genetic polymorphisms, with membership in different demographic and socioeconomic groups, with a variety of dietary patterns and with many medical conditions that are not apparently inflammatory. Finally, minor CRP elevation bears negative prognostic implications for many conditions, particularly age-related diseases, and predicts mortality in both diseased and apparently healthy individuals. In sum, minor CRP elevation is associated with a great many diverse conditions, some of which are, or may prove to be, causal. Many of these reported associations imply a mild degree of tissue stress or injury, suggesting the hypothesis that the presence of distressed cells, rather than a resulting inflammatory response, is commonly the stimulus for CRP production.

Usefulness of B-type natriuretic peptide and C-reactive protein in predicting the presence or absence of left ventricular hypertrophy in patients with systemic hypertension

The diagnosis of left ventricular (LV) hypertrophy, an independent predictor of death and cardiovascular events, is difficult without using echocardiography. This study tested the hypothesis whether C-reactive protein (CRP) and B-type natriuretic peptide (BNP) would be useful to exclude echocardiographic LV hypertrophy. Consecutive hypertensive outpatients were asked to participate. Exclusion criteria were overt heart failure, severe renal insufficiency or any other severe concomitant illness. A venous blood sample was taken to measure plasma CRP and BNP concentrations. Echocardiographic LV hypertrophy was defined as LV mass > or =125 g/m2 for men and > or =110 g/m2 for women. In total, 320 patients were studied, and 37 patients (12%) had echocardiographic LV hypertrophy. Patients with LV hypertrophy were significantly older and had higher CRP and BNP concentrations and higher systolic blood pressure than those without LV hypertrophy. The optimal cut-off points for the diagnosis of LV hypertrophy were 35 pg/ml for BNP (sensitivity 73%, specificity 72%) and 2.5 mg/L for CRP (sensitivity 68%, specificity 59%). Only 1 of 123 patients with values of BNP and CRP less than the optimal cut-off point had echocardiographic LV hypertrophy, resulting in a high negative predictive value of 99% for the 2 blood tests combined to exclude LV hypertrophy. In conclusion, in hypertensive patients, echocardiographic LV hypertrophy can be excluded on the basis of a single blood sample for the determination of BNP and CRP.

Relation of left ventricular concentric remodeling to levels of C-reactive protein and serum amyloid A in patients with essential hypertension

In this study, we investigated possible relations between left ventricular (LV) concentric remodeling and plasma levels of high-sensitivity C-reactive protein (hs-CRP) and serum amyloid-A (SAA) in subjects who had essential hypertension; 65 consecutive subjects who had hypertension, did not have diabetes, and had normal LV mass were categorized as those whose LV relative wall thickness was <0.44 (n = 41) and those whose relative wall thickness was > or =0.44. Venous blood samples were collected for determination of metabolic profile and plasma levels of hs-CRP and SAA. Subjects whose relative LV wall thickness was > or =0.44 compared with those whose relative LV wall thickness was <0.44 had significantly increased systolic blood pressure by 4.5 mm Hg (p = 0.015) and higher levels of plasma hs-CRP (1.80 vs 1.39 mg/L, p = 0.001) and SAA (10.22 vs 4.86 mg/dl, p = 0.000), although the 2 groups did not differ with regard to age, gender, waist-to-hip ratio, and diastolic blood pressure (p = NS for all). In the entire study population, log hs-CRP and SAA exhibited positive relations with systolic blood pressure (r = 0.21 and r = 0.29, respectively; p <0.05 for the 2 markers) and relative wall thickness (r = 0.26 and r = 0.81, respectively; p <0.05 for the 2 markers). Multiple linear regression analysis showed that age, gender, and diastolic blood pressure were significantly associated with LV mass index (p <0.05), whereas gender, body mass index, log hs-CRP, and SAA were significantly associated with relative wall thickness (p <0.003). By analysis of covariance, log hs-CRP and SAA were significantly different between subjects whose relative LV wall thickness was > or =0.44 and those whose relative LV wall thickness was <0.44 after the adjustment for age, gender, body mass index, and systolic/diastolic blood pressure (p <0.005 for the 2 markers). In conclusion, alterations in LV geometry are associated with increased serum CRP and SAA levels in patients who are newly diagnosed with essential hypertension.

Diabetic cardiomyopathy: mechanisms, diagnosis and treatment

Independent of the severity of coronary artery disease, diabetic patients have an increased risk of developing heart failure. This clinical entity has been considered to be a distinct disease process referred to as 'diabetic cardiomyopathy'. Experimental studies suggest that extensive metabolic perturbations may underlie both functional and structural alterations of the diabetic myocardium. Translational studies are, however, limited and only partly explain why diabetic patients are at increased risk of cardiomyopathy and heart failure. Although a range of diagnostic methods may help to characterize alterations in cardiac function in general, none are specific for the alterations in diabetes. Treatment paradigms are very much limited to interpretation and translation from the results of interventions in non-diabetic patients with heart failure. This suggests that there is an urgent need to conduct pathogenetic, diagnostic and therapeutic studies specifically in diabetic patients with cardiomyopathy to better understand the factors which initiate and progress diabetic cardiomyopathy and to develop more effective treatments.

Prevalence of an abnormal ankle-brachial index in patients with primary antiphospholipid syndrome: preliminary data

OBJECTIVES

To evaluate the prevalence of abnormal ankle-brachial indexes (ABIs), their relationship with other cardiovascular risk factors and/or the presence of antiphospholipid antibodies (aPL), and the clinical use of the ABI in patients with primary antiphospholipid syndrome (primary APS).

METHODS

An 8 MHz Doppler probe was used in the arms and legs to assess the ABI in 43 patients with primary APS (mean (SD) age 40.2 (7.9) years) and 49 healthy subjects (aged 41.0 (11.7)) matched for age and sex. Data on traditional cardiovascular risk factors, such as hypertension, hypercholesterolaemia, presence of diabetes mellitus, nephrotic syndrome or renal failure, smoking, and other variables, were collected at that time for all subjects. A ratio of the highest blood pressure from the posterior tibial or pedal arteries of each leg to the highest blood pressure from the brachial arteries <1.00 was considered abnormal.

RESULTS

Abnormal ABIs were found in 8/43 (19%) patients with primary APS and 2/49 (4%) controls (p = 0.026). No correlation between abnormal ABI and traditional cardiovascular risk factors nor with the presence of aPL was found.

CONCLUSION

Abnormal ABIs are more common in primary APS than in healthy controls, possibly indicating a subclinical atherosclerotic process in these patients.