Comparison of the extent and severity of coronary artery disease in patients with acute myocardial infarction with and without microalbuminuria

Microalbuminuria: Correlation With Prevalence and Severity of Coronary Artery Disease in Non-Diabetics

BACKGROUND

Previous studies have shown that microalbuminuria (MAU) is an independent risk factor for cardiovascular diseases in diabetics, hypertensive patients and in the general population. However, the correlation of MAU with the severity of coronary artery disease (CAD) in non-diabetic patients has not been addressed in detail. This study aimed to investigate the relationship between MAU and severity of angiographically confirmed CAD in non-diabetic patients.

METHODS

This was a cross-sectional study, which included 90 non-diabetic patients with documented CAD by coronary angiography. The ratio of urine albumin to creatinine was used to define MAU and severity of CAD was estimated using SYNTAX score. Patients were divided into two groups: group I that included patients without MAU and group II that included patients with MAU.

RESULTS

Out of 90 non-diabetic CAD patients, 62 (68.9%) were in group I (MAU negative) and 28 (31.1%) were in group II (MAU positive). There was statistically significant difference in the median SYNTAX score between the groups (21 vs. 28, P < 0.001). The prevalences of double vessel CAD and triple vessel CAD were significantly higher in MAU positive group. There was a strong relationship between the presence of MAU and the extent and complexity of CAD (r = 0.094; P < 0.001).

CONCLUSION

Thus, we conclude that patients with MAU have more severe angiographically detected CAD than those without MAU, and MAU exhibits a significant association with the presence and severity of CAD.

Microalbuminuria is Associated With the Severity of Coronary Artery Disease Independently of Other Cardiovascular Risk Factors

The potential early predictive value of microalbuminuria (MA) in the estimation of atherosclerosis and the relation between the degree of urinary albumin excretion and the extent of coronary artery disease (CAD) were investigated. Patients (n = 159) with stable angina pectoris and angiographically significant stenosis in at least 1 of the major coronary arteries were included. Microalbuminuria was measured by immunoturbidimetry. The extent of coronary artery stenosis was graded using the Gensini score. The Gensini score was significantly greater in patients who had MA. Also, the Gensini increased by 0.15 units with 1 unit increase in MA. In the groups who had diabetes mellitus and hypertension, there was no correlation between MA and Gensini score. The results of the present study suggest that MA is associated with the severity of CAD independent of other cardiovascular risk factors.

Prevalence of microalbuminuria in hypertensive patients and its associated cardiovascular risk in clinical cardiology: Moroccan results of the global i-SEARCH survey - a sub-analysis of a survey with 21,050 patients in 26 countries worldwide

Objectives

To determine the prevalence of microalbuminuria (MAU) in hypertensive outpatients visiting a cardiologist’s office or clinic and to describe the relationship between MAU and cardiovascular risk factors.

Methods

This was an international, observational, cross-sectional study of 22 282 patients, with 457 subjects from Morocco in 40 cardiology centres. Inclusion criteria were: male and female outpatients aged ≥ 18 years with currently treated or newly diagnosed hypertension (≥ 140/90 mmHg at rest on the day of the study visit) and no reason for false positive microalbuminuria dipstick tests.

Outcome measures

Prevalence of microalbuminuria assessed using a dipstick test, co-morbid cardiovascular risk factors or disease and their relationship with the presence of MAU, and role of pharmacotherapy in modulating the prevalence of MAU.

Results

The prevalence of microalbuminuria in hypertensive patients in Morocco (67.8%) was high compared to the worldwide prevalence (58.3%). Despite the fact that all physicians regarded MAU as important for risk assessment and therapeutic decisions, routine MAU measurement was performed in only 35% of the practices. In clinical cardiology, MAU is highly correlated with a wide variety of cardiovascular risk factors and cardiovascular disease.

While angiotensin receptor blockers (ARBs) appeared to be associated with the lowest risk of MAU, calcium channel blockers (CCBs) were more often used in this patient group.

Conclusions

Hypertensive, high-risk cardiovascular patients are common in clinical cardiology. Given the high prevalence detected, screening of MAU in addition to more aggressive multi-factorial treatment to reduce blood pressure as well as other cardiovascular risk factors is required.

Determining the relationship between metabolic syndrome score and angiographic severity of coronary artery disease

BACKGROUND

Cardiovascular disease is leading cause of mortality and morbidity in developed and developing countries. Metabolic syndrome (MS) is a risk factor for coronary artery disease (CAD). The effect of MS on angiographic severity of CAD is not well defined. The aim of this study was to examine the effect of MS on angiographic severity of CAD by using Gensini score.

METHODS

The total number of 1003 patients who underwent elective coronary angiography in catheter laboratory were included in the study. MS score based on National Cholesterol Education Program (NCEP) Adult Treatment Panel III (ATP III) criteria which ranged between zero and five were calculated for each subject. Gensini scores were determined by examining coronary angiograms of the patients.

RESULTS

The study population consisted of 634 (63%) male, and 369 (37%) female subjects. The mean age was 59 +/- 11. MS based on NCEP ATP III was present in 246 (25%) patients. CAD was present in 691 patients (69%). The median of Gensini score was five (0-192) in the total sample, 18 (1-192) in the patients with CAD and 25 (0-192) in the patients with MS. A positive correlation was found between MS score and Gensini score (r = 0.402, p < 0.001).

CONCLUSIONS

In this study, it was determined that as the severity of MS increases, the angiographic severity of CAD increases as well. Besides, the most important factor on Gensini score was diabetes mellitus in male and hypertension in female subjects.

Interleukin-18: a strong predictor of the extent of coronary artery disease in patients with unstable angina

The aim of this study was to confirm that plasma interleukin (IL)-18 level is associated with the extent of coronary artery disease in unstable angina patients. Previous studies have shown that patients with unstable angina have significantly higher plasma IL-18 levels than healthy volunteers. However, the association between IL-18 and the extent of coronary artery atherosclerosis in patients with unstable angina remains unclear. Plasma concentrations of IL-18 and high-sensitivity C-reactive protein (hs-CRP) were measured in 166 consecutive patients admitted for coronary arteriography. One hundred and eighteen patients with unstable angina had coronary artery disease (coronary artery disease group; severity score: 2.32 +/- 1.47; Gensini score: 31.3 +/- 25.9), and 48 patients with coronary risk factors and without coronary artery lesions served as the risk control group. Plasma levels of IL-18 were higher in the coronary artery disease group than in the risk control group (P = 0.062). Additionally, plasma levels of IL-18 were significantly higher in 77 coronary artery disease patients with severity score > or =2 than in the risk control group (242.3 +/- 110.6 vs 209.8 +/- 120.3 pg/ml, P = 0.016). By univariate analysis, log-transformed plasma IL-18 concentration was positively correlated with coronary artery disease severity score (r = 0.244, P = 0.009). By multiple regression analyses, the association between coronary artery disease severity score and IL-18 remained significant (beta = 0.733, P = 0.017) when controlling for age, diabetes mellitus and left ventricular ejection fraction. Additionally, coronary artery disease severity score was greater in the highest tertile (>246 pg/ml) of plasma IL-18 levels than in the middle (176-246 pg/ml) and the lowest (<176 pg/ml) tertiles (2.79 +/- 1.52 vs 2.05 +/- 1.08 vs 2.13 +/- 1.66, P = 0.028). Of note, plasma hs-CRP level had no significant correlation with coronary artery severity. Plasma IL-18 level is associated with the extent of coronary artery disease in unstable angina patients, suggesting the link between IL-18 and coronary artery atherosclerosis in these patients.

Genome-wide scans for microalbuminuria in Mexican Americans: the San Antonio Family Heart Study

PURPOSE

Microalbuminuria, defined as urine albumin-to-creatinine ratio of 0.03 to 0.299 mg/mg, is a major risk factor for cardiovascular disease. Several genetic epidemiological studies have established that microalbuminuria clusters in families, suggesting a genetic predisposition.

METHOD

We estimated heritability of microalbuminuria and performed a genome-wide linkage analysis to identify chromosomal regions influencing urine albumin-to-creatinine ratio in 486 Mexican Americans from 26 multiplex families.

RESULTS

Significant heritability was demonstrated for urine albumin-to-creatinine ratio (h = 24%, P < 0.003) after accounting for age, sex, body mass index, triglycerides, and hypertension. Genome scan revealed significant evidence of linkage of urine albumin-to-creatinine ratio to a region on chromosome 20q12 (LOD score of 3.5, P < 0.001) near marker D20S481. This region also exhibited a LOD score of 2.8 with diabetes status as a covariate and 3.0 with hypertension status as a covariate suggesting that the effect of this locus on urine albumin-to-creatinine ratio is largely independent of diabetes and hypertension.

CONCLUSION

Findings indicate that there is a gene or genes located on human chromosome 20q12 that may have functional relevance to albumin excretion in Mexican Americans. Identifying and understanding the role of the genes that determine albumin excretion would lead to the development of novel therapeutic strategies targeted at high-risk individuals in whom intensive preventive measures may be most beneficial.

Ascending aortic blood pressure-derived indices are not correlated with the extent of coronary artery disease in patients with impaired left ventricular function

BACKGROUND

Ascending aortic blood pressure-derived indices were shown to be related to coronary atherosclerosis. Unfortunately, most studies published so far included patients with preserved left ventricular function. Therefore, the aim of the present study was to investigate the relation between ascending aortic blood pressure-derived indices and the extent of coronary atherosclerosis in patients with impaired left ventricular function.

METHODS

The study group consisted of 375 patients (302 men and 73 women; mean age: 59.0+/-10.1 years) with angiographically confirmed coronary artery disease and ejection fraction < or =55%. Invasive ascending aortic blood pressure during catheterization and conventional sphygmomanometer measurements were taken.

RESULTS

None of the brachial or aortic blood pressure-derived indices differed between patients with one-, two- and three-vessel coronary artery disease. They were not independently related to the risk of having three-vessel coronary artery disease in none of the constructed models in logistic regression analysis. Moreover, none of the studied indices was correlated with Gensini or severity scores. We also did not find any significant correlation between blood pressure-derived indices and extent of coronary atherosclerosis in patients with ejection fraction < or =25%, 25-40% or >40%.

CONCLUSION

Ascending aortic blood pressure-derived indices are not correlated with the severity of coronary atherosclerosis in patients with coronary artery disease and impaired left ventricular function.

What is the evidence that microalbuminuria is a predictor of cardiovascular disease events?

PURPOSE OF REVIEW

This review describes recently published studies evaluating the association between microalbuminuria and the development of cardiovascular disease events either in the presence of diabetes or hypertension, or in the population as a whole.

RECENT FINDINGS

Prospective studies confirm that microalbuminuria is predictive, independently of classical risk factors, of cardiovascular disease events and all-cause mortality within groups of patients with diabetes or hypertension and in the general population. However, these studies suggest that levels of albuminuria below the conventional cutoff point definition of microalbuminuria are significantly associated with cardiovascular morbidity and mortality. The pathophysiological mechanism underyling this association is still uncertain. Data from recent intervention studies suggest that treatment with angiotensin-converting enzyme inhibitors or angiotensin II receptor blockers, as well as intensive multi-factorial intervention including behaviour modification and targeted pharmacotherapy in patients with microalbuminuria, offers significant reduction in cardiovascular and renal morbidity in people with albuminuria.

SUMMARY

Future absolute risk prediction scores for primary cardiovascular events could include microalbuminuria as a modifiable risk factor. The association between levels of albuminuria and cardiovascular outcomes in individuals within the normoalbuminuric range questions the current categorical definition of microalbuminuria. Intensive multifactorial interventions, including the use of agents that affect the renin-angiotensin pathway, are effective in reducing cardiovascular risk in patients with microalbuminuria and diabetes or hypertension.