Serum homocysteine, creatinine, and glucose as predictors of the severity and extent of coronary artery disease in asymptomatic members of high-risk families

MTHFR C677T gene polymorphism and the severity of coronary lesions in acute coronary syndrome

The association between methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism, circulating levels of homocysteine (Hcy), and the severity of coronary lesion in patients with acute coronary syndrome (ACS) remains unknown.Consecutive ACS patients were included. MTHFR C677T polymorphisms were determined via amplification refractory mutation system-polymerase chain reaction (ARMS-PCR). Gensini scores were used to evaluate the severity of coronary lesions.Three hundred ten ACS patients were included, and grouped according to the MTHFR C677T polymorphism variant: CC (n = 78, 25.2%), CT (n = 137, 44.2%), and TT (n = 95, 30.6%) groups. No significant differences were detected with respect to baseline characteristics. Patients in TT group had significantly higher Hcy, and significantly lower folic acid (FA) levels as compared with those in the other 2 groups (P < .05 for both). More importantly, patients with TT had more severe coronary lesions as compared with those from the other 2 groups, as evidenced by higher Gensini scores (P < .05 for both); however, no significant differences were observed with respect to the numbers of affected coronary arteries, or the number, length, and diameter of stents implanted in each group (P > .05 for all). On multivariate logistic regression analysis, presence of a T allele in MTHFR C677T was found to be independently associated with higher circulating Hcy (odds ratio [OR] = 1.06, 95% confidence interval [CI]: 1.01-1.12, P = .024), and higher Gensini scores (OR: 1.01, 95% CI: 1.00-1.02, P = .046).MTHFR C677T TT polymorphism was associated with higher Hcy levels and more severe coronary lesions in patients with ACS.

Glycosylated haemoglobin and coronary atherosclerosis in non-diabetic patients: is it a prognostic factor?

BACKGROUND

Some studies aimed to evaluate the relationship between HbA1c and coronary artery disease (CAD). However, it is well known that long-term glycometabolic disorders put the heart at risk for CAD. Considering the inconsistencies between previous studies, this study aimed to investigate the relationship between HbA1c and coronary artery atherosclerosis.

METHODS

A cross-sectional study was conducted on 411 non-diabetic patients who underwent their first coronary angiography between November 2013 and December 2014 in Baqiyatallah Hospital. Blood samples were taken before angiography. Coronary angiograms were reported and reviewed by two cardiologists according to the Gensini score. They were not aware about the patients' HbA1c level. Severity of CAD was determined through ascertaining the prevalence of multi-vessel disease, extent of CAD (single-, two- or three-vessel disease or left main stem stenosis (>50%)). Data analysis was performed by using SPSS software.

RESULTS

A total of 411 patients (252 men and 159 women) were evaluated. Angiography was normal in 67 patients (16.3%), 30.7% had single-vessel disease (SVD), and 29.1%, 20.7% and 3.2% had two-, three- and multivessel disease, respectively. Based on the ROC curve, the HbA1c was able to differentiate between patients with and without coronary atherosclerosis (p < .001, cut-off point = 5.45). The cut-off points for differentiation of severe CAD and patients with 75-100% stenosis of coronary artery were 5.55 (p < .001) and 5.65 (p < .001), respectively.

CONCLUSIONS

The present study demonstrated that HbA1c might be an independent diagnostic factor in non-diabetic patients with severe coronary atherosclerosis.

A new coronary artery disease grading system correlates with numerous routine parameters that were associated with atherosclerosis: a grading system for coronary artery disease severity

Background

Several scoring systems have tried to determine the severity of coronary artery disease (CAD) to investigate the connection between CAD severity and laboratory parameters.

Methods

In total, 189 male (mean age: 61.86±10.77 years) and 75 female CAD patients (mean age: 67.84±7.70 years) were recruited and underwent angiography, which determined stenosis grade, of 17 coronary segments: no points for each nonstenosed segment or only calcified segments, one point for each stenosis from <30% to <50%, two points for each stenosis from 50% to <70%, and three points for each stenosis >70%. The points were added and should represent the severity of patients’ CAD.

Results

The coronary score correlated positively with systolic blood pressure, creatinine, blood urea nitrogen, lipase, glucose, glycated hemoglobin, triglycerides, C-reactive protein, fibrinogen Clauss, and leukocytes, and correlated negatively with Cl⁻, iron, and high-density lipoprotein cholesterol. Stepwise multiple regression analysis with backward elimination revealed diabetes status, sex, and fibrinogen Clauss as significant predictors of coronary score.

Conclusion

The coronary score delivers a quite simple but very precise tool for the quantification of CAD severity. These results show plainly the connection between CAD severity and the lipid, glucose, coagulation, and immunologic status of CAD patients, and substantiate the importance of sufficient treatment in this group of patients – in particular, CAD patients suffering from type 2 diabetes mellitus. The coronary score would offer a suitable tool for the investigation of the connection between CAD and new biomarkers. Further studies are needed to investigate the correlation of the coronary score with outcome parameters (eg, death).

Hemoglobin A1C in non-diabetic patients: an independent predictor of coronary artery disease and its severity

AIMS

To determine the association between glycated hemoglobin (HbA1c) and angiographically proven coronary artery disease (CAD) and its severity in nondiabetic individuals.

METHODS

We enrolled 299 consecutive individuals undergoing coronary angiography for suspected ischemia. Patients were included if they had no history of prior revascularization or diabetes mellitus and had fasting blood glucose<126mg/dl (7.0mmol/l) and HbA1c<6.5% (47mmol/mol). The severity of the CAD was also evaluated using the Gensini score. Serum HbA1c (NGSP certified Method), highly sensitive C-reactive protein (hsCRP), lipid profile, insulin and APO lipoprotein A1 and B100 levels were measured.

RESULTS

Mean age was 58.8±10.4 year; 60.9% men. One hundred forty seven patients had significant CAD (≥50% stenosis in any major vessel). With increasing HbA1c levels, there was a significant increase in the prevalence of CAD and number of vessels involved. In multivariate analysis, HbA1c emerged as an independent predictor of significant CAD (OR: 2.8, 95% CI: 1.3-6.2, p=0.009). Adjusted ORs for the occurrence of CAD were highest in subjects with both hsCRP and HbA1c in the upper 2 quartiles (OR: 4.183; 95% CI: 1.883-9.290, p<0.0001). There was a significant association between Gensini score and increasing HbA1c tertiles (p=0.038). The ideal cut-off value of HbA1c for prediction of the occurrence of CAD was 5.6% 38mmol/mol) (sensitivity: 60.5%, specificity: 52%).

CONCLUSIONS

In non-diabetic subjects, HbA1c could be utilized for risk stratification of CAD and its severity, independent of traditional cardiovascular risk factors, insulin resistance and inflammatory markers.

Renal function is related to severity of coronary artery calcification in elderly persons: the Rotterdam study

Background

Coronary artery calcification (CAC) has been proposed to be the underlying mechanism of the increased risk of coronary heart disease with reductions in glomerular filtration rate (GFR). Since renal function diminishes with aging we examined the association between GFR and CAC in the Rotterdam Study, a population-based study of elderly individuals.

Methods

The study was performed in 1703 subjects without a history of coronary heart disease. GFR was estimated using the modification of diet in renal disease equation. We used analysis of covariance to test for mean differences in CAC between GFR tertiles.

Results

The mean CAC scores in the middle and lowest GFR tertile did not significantly differ from the mean CAC score in the highest GFR tertile (geometric mean CAC score 4.1 and 4.3 vs 4.2). In a multivariable model the mean CAC score did also not differ between the GFR tertiles. As the interaction term between age and GFR was significant (P = 0.037), we divided the population in two age categories based on median age of 70 years. Below 70 years, the mean CAC scores did not differ between the GFR tertiles. Above median age, mean CAC score in the lowest GFR tertile was significantly higher than the mean CAC score in the highest tertile in a multivariable model (CAC 4.9 vs 4.5, p = 0.010).

Conclusion

In this population-based study we observed that the association between CAC and GFR is modified by age. In participants at least 70 years of age, a decrease in GFR was associated with increased CAC.

The Relationship between Glucose Tolerance and Severity of Coronary Artery Disease Using the Gensini Score

Consecutive patients (n = 235) with coronary ischemia were studied; 69 patients (29%) had diabetes. An oral glucose tolerance test (OGTT) was administered to the 166 patients without diabetes; 76 (46%) had normal glucose tolerance (group I = NGT), 68 (41%) had impaired glucose tolerance ([IGT] group II = IGT), and 22 (13%) had diabetic glucose tolerance (DGT). The DGT patients were added to the known diabetics forming (Group III; n = 91). Multivessel disease was significantly more prevalent in group III; 30 patients (43%) in group I, 32 patients (51%) in group II, and 57 patients (69%) in group III ( P = .002). Gensini scores were 43.20 ± 24.92 in group I, 54.22 ± 42.61 in group II, and 60.59 ± 38.21 in group III. ( P = .037) The severity of coronary artery disease is related to abnormal glucose tolerance. Patients with IGT could be neglected in terms of interventions focused to improve risk factors.

Renal dysfunction is the most important predictor of the extent and severity of coronary artery disease in patients with diabetes mellitus

OBJECTIVES

Diabetic patients tend to have more extensive and diffuse coronary artery disease (CAD) that may contribute to the less favorable outcomes in them. The aim of this study was to elucidate the predictors of the angiographic severity and extent of CAD in patients with diabetes.

METHODS

A total of 203 diabetic patients (116 men; mean age, 61.9+/-10.8) who were referred for a first coronary angiogram were included. The extent and severity of CAD was assessed in several ways. The first was a simple classification in one-vessel, two-vessel, and three-vessel disease scoring system. The total numbers of segments with > or = 20 and > or = 50% stenosis were calculated as CASS 20 and CASS 50 scores, respectively. Hamsten and Gensini scores were also calculated.

RESULTS

Of the 203 patients included in the study, 175 (86.2%) had CAD. Multivariate ordinal logistic regression analysis showed that age (Wald 5.741, P=0.017), glomerular filtration rate (Wald 5.032, P=0.025), previous myocardial infarction (Wald 10.955, P=0.001), and family history of CAD (Wald 7.236, P=0.007) were independent predictors of the severity of CAD, as assessed by the clinical zero-vessel to three-vessel disease scoring system. On stepwise multiple linear regression analysis, glomerular filtration rate was an independent predictor of the CASS 20 (r=-0.221, P=0.004), CASS 50 (r=-0.239, P=0.005), Gensini (r=-0.328, P<0.001), and Hamsten (r=-0.320, P<0.001) scores. Previous myocardial infarction was an independent predictor of the CASS 50 (r=0.355, P<0.001), Gensini (r=0.350, P<0.001), and Hamsten (0.256, P<0.001) scores. Age and sex were independent predictors for the CASS 50 (r=0.174, P=0.039; r=0.172, P=0.016, respectively) and Hamsten (r=0.212, P=0.011; r=0.244, P=0.001, respectively) scores.

CONCLUSION

Renal function is one of the most important factors associated with the extent and severity of coronary atherosclerosis, whereas classical coronary risk factors and the degree of metabolic control were not associated with the severity of coronary atherosclerosis in diabetic patients.

Homocysteine, Folate and Vitamin B12 in Patients with Coronary Heart Disease

BACKGROUND/AIMS

Homocysteine and possibly also folate and vitamin B(12) are involved in the pathogenesis of cardiovascular disease. We investigated the prevalence of hyperhomocysteinemia in patients with coronary heart disease (CHD), as well as folate and vitamin B(12), the main nutritional factors determining the level of homocysteine.

METHODS

Patients with angiographically documented CHD were prospectively investigated (n = 315, 70% male, mean age 61 [range 36-81] years). Fasting total serum homocysteine was determined by high-performance liquid chromatography and fluorescence detection. Folic acid and vitamin B12 were measured with AxSYMR Systems.

RESULTS

Median homocysteine concentrations for homocysteine, folate and vitamin B12 were 12.8 micromol/l, 6.8 ng/ml and 345 pg/ml, respectively. Homocysteine levels >10 micromol/l were found in 82% of men and 73% of women. In 19% of the patients serum folate was <3 ng/ml and 22% of the patients had serum vitamin B12 values <250 pg/ml. In a multivariate linear regression model, folate and vitamin B(12) showed significant negative correlations to homocysteine, explaining 5 and 3% of its variability. Age and creatinine were the most important determinants for serum homocysteine, contributing 12 and 7%, respectively.

DISCUSSION

The main determinants of total homocysteine in patients with CHD are higher age and increased creatinine. The association of lower levels of folate and vitamin B12 with higher levels of homocysteine may indicate poor dietary habits in these patients.

Plasma homocysteine levels and the left ventricular systolic function in coronary artery disease patients

BACKGROUND

Numerous studies have shown a relationship between hyperhomocysteinemia, atherothrombosis and cardiovascular mortality. However, an association between hyperhomocysteinemia and the extent of coronary artery disease (CAD) remains controversial whereas its relationship with left ventricular systolic function has not been established.

METHODS

One hundred and fifty-seven patients with angiographically defined CAD were included. The relationships between hyperhomocysteinemia, severity of CAD and left ventricular systolic function were studied. Left ventricular systolic function was determined primarily by ventriculography. The severity of CAD was determined through coronary angiography using the Gensini score and the number of vessels with > or = 50% stenosis.

RESULTS

The mean fasting plasma homocysteine level was 13.4 mumol/l+/-0.5 SE. Elevated levels of homocysteine correlated significantly with increased severity of CAD both by the Gensini scores (r-value = 0.344, P < 0.0005) and the total number of diseased vessels (r-value = 0.387, P < 0.0005). The patients with hyperhomocysteinemia were found to have significantly reduced left ventricular ejection fraction (r-value = -0.382, P < 0.0005). A multivariate regression analysis revealed homocysteine level to be an independent predictor of left ventricular systolic function. In addition, adjusted analysis revealed hyperhomocysteinemia to be associated with global left ventricular dysfunction.

CONCLUSION

In patients with CAD, homocysteine levels correlate independently with left ventricular systolic function. The mechanism of this association between homocysteine and left ventricular systolic function is unknown but may be due to a direct effect of homocysteine on myocardial function separate from its effects on coronary atherosclerosis.