Relationship between extent of coronary artery disease and correlative risk factors

Prevalence of conventional risk factors and lipid profiles in patients with acute coronary syndrome and significant coronary disease

BACKGROUND

Among patients with coronary artery disease (CAD), 80%-90% present at least one conventional risk factor. On the other hand, lipid profile modification after a cardiovascular event related to acute coronary syndrome (ACS) has been recognized. The prevalence of conventional risk factors and the lipid profile at the time of admission in patients with ACS and significant CAD (stenosis ≥50%) determined through coronary angiography is not well described.

METHODS

We studied 3,447 patients with a diagnosis of ACS and significant CAD with stenosis ≥50%, as shown o n angiography. We recorded the presence of conventional risk factors, including smoking, hypertension, dyslipidemia, and diabetes. In addition, we analyzed the lipid profiles within the first 24 hours of admission. We analyzed the studied population and compared findings according to sex.

RESULTS

Most patients (81.7%) were male. ST-elevation myocardial infarction was present in 51.3% of patients, and non-ST-elevation acute coronary syndrome was present in 48.7%. The most frequent risk factor was smoking, which was present in 68% of patients, followed by hypertension (57.8%), dyslipidemia (47.5%), and diabetes (37.7%). In women, the most frequent risk factors were hypertension, diabetes, and dyslipidemia, whereas in men, smoking was the most frequent. We identified at least one risk factor in 95.7% of all patients, two or three risk factors in 62%, and four risk factors in 8.6% of patients. The lipid profile analysis revealed that 85.1% of patients had some type of dyslipidemia, and the most frequent was low levels of high-density lipoprotein cholesterol (68.6% of cases).

CONCLUSION

We found at least one conventional risk factor in 95.7% of patients with ACS and significant CAD. The lipid profile analysis revealed that two thirds of cases had low high-density lipoprotein cholesterol levels.

Traditional cardiovascular risk factors and severity of angiographic coronary artery disease in the elderly

Over 80% of annual coronary heart disease mortality occurs in the elderly, a rapidly expanding subset of the population. The authors retrospectively examined the relationship between traditional cardiovascular risk factors and atherosclerotic coronary artery disease burden in a cohort of 631 elderly patients undergoing angiography. Age and male sex but not hypertension or dyslipidemia were predictors of presence of obstructive coronary artery disease (Duke score >or=2). Only diabetes mellitus emerged as an independent predictor of obstructive coronary artery disease burden. Smoking was found to be predictive of left main coronary artery disease. In summary, severity of angiographic disease in the elderly as assessed by Duke Myocardial Jeopardy scoring appears to correlate poorly with prevalence of established traditional cardiovascular risk factors.

Obesity, body fat and coronary atherosclerosis

BACKGROUND

Recent prospective studies have provided compelling evidence that obesity is a risk factor for the occurrence of clinical coronary events. However, the link between angiographically determined coronary atherosclerosis and obesity still remains controversial. We conducted this cross-sectional study in a clinical setting to investigate the relation of the obesity and body fat (BF) with angiographically defined coronary atherosclerosis.

PATIENTS AND METHODS

Six hundred and seventy-three men (median age 64 years) and four hundred and twenty-eight women (median age 69 years) who underwent coronary angiography for suspected or known coronary heart disease were analyzed. The body mass index (BMI) and the BF were used as main exposure variables, and either the presence of significant (> or =50%) coronary diameter stenosis or a coronary artery disease severity score were defined as outcome variables, in a sex-specific logistic regression analysis.

RESULTS

Among male patients, BF was slightly higher with increasing number of vessels involved (adjusted P for trend <0.05). In contrast, BMI showed no association with presence and severity of coronary artery disease (CAD). The odds ratios (ORs) for the presence of significant stenosis across quartiles of BMI were 1.0 (reference), 0.9, 1.1 and 0.7 (adjusted P for trend 0.61). This result did not differ between younger and older men. Among females, however, both BF and BMI were not significantly associated with an increasing number of vessels involved.

CONCLUSION

These results suggested that BF may be predictive of an increasing number of coronary vessels involved among male patients, but not among female patients. This study failed to detect a positive association of presence and severity of CAD with BMI.

Obesity, body fat distribution and coronary atherosclerosis among Japanese men and women

OBJECTIVE

To investigate the relation of the obesity and body-fat distribution with angiographically defined coronary atherosclerosis.

DESIGN

Cross-sectional study in a clinical setting.

SUBJECTS

Three hundred and twenty men (median age, 59 y) and 212 women (median age, 67 y) who underwent coronary angiography for suspected or known coronary heart disease at 5 cardiology departments between September 1996 and August 1997. Patients with disease duration >1 y were excluded.

MEASUREMENTS

The body mass index (BMI) and the waist to hip circumference ratio (WHR) were used as main exposure variables, and either the presence of significant coronary stenosis or the Gensini's score (> or =10 vs<10) as an outcome variable, in a sex-specific multiple logistic regression analysis controlling for age, hospital, and other coronary risk factors.

RESULTS

Among male patients, BMI was progressively higher with an increasing number of vessels involved (P trend=0.05); the adjusted odds ratios for the presence of significant stenosis across quartiles of BMI were 1.0 (reference), 1.1, 1.9 and 2.5 (P trend=0.02), and the positive association was more pronounced for younger patients. Among females, however, such associations were not evident. Employing the Gensini's score as an outcome gave similar results. WHR was not significantly associated with either outcome regardless of sex.

CONCLUSION

These results suggested that BMI was predictive of coronary stenosis among male patients, but not among female patients. Unlike most previous studies, this study failed to detect a positive association with WHR.

The number of stenotic coronary arteries and passive smoking exposure from husband in lifelong non-smoking women in Xi'an, China

The relationship between the number of stenotic coronary arteries and passive smoking exposure from the husband was examined in a retrospective study of 78 cases with stenotic coronary arteries and 83 controls with normal coronary arteries. All the 161 subjects were examined by coronary arteriography and were Chinese women who had never smoked cigarettes (i.e. lifelong non-smokers). The Pearson's and Spearman's correlation coefficients between the number of stenotic coronary arteries and passive smoking exposure indices were 0.27-0.29 and 0.25-0.28 (all with P < 0.01), respectively. The linear prediction equations from multiple regression analysis showed that passive smoking exposure, after adjustment for other major risk factors, was a significant predictive variable for the number of stenotic coronary arteries. The multiple response logistic regression model was used to estimate the odds ratio of stenotic coronary arteries for passive smoking exposure categories. The crude and adjusted odds ratios showed that the number of stenotic arteries increased with the amount of exposure to passive smoking from the husband. These results provide new evidence to support that passive smoking is causally associated with coronary heart disease.

Relation of angiographically defined coronary artery disease to serum lipoprotein levels

The relationship of coronary artery disease to plasma lipoproteins was examined in 43 men admitted to our unit with suspected ischemic heart disease. Coronary arteriography was performed, and a score reflecting the severity of disease was assigned to the angiogram. Plasma, obtained after a 12-h overnight fast, was assayed for triglycerides, total cholesterol, high-density lipoprotein (HDL) cholesterol, and HDL-3 cholesterol. HDL-2 cholesterol was found by subtraction. The cholesterol contents of very low-density lipoprotein (VLDL) and low-density lipoprotein (LDL) were quantitated by the Freidwald equation. Men with high coronary scores tended to be older, and subjects with moderate coronary disease had significantly higher total and LDL cholesterol values than those with minimal disease. Age was the only factor to be significantly associated with coronary score and there was no significant association between coronary score and total LDL and HDL cholesterol or its subfractions when the age factor was taken into account.

The significance of psychosocial factors in predicting coronary disease in patients with valvular heart disease

Several prognostic indices for predicting various aspects of coronary artery disease were significantly improved by the inclusion of psychosocial factors. 218 patients with valvular heart disease who had undergone routine coronary arteriography before valve replacement were studied in terms of cigarettes smoked, family history of ischaemic heart disease, HDL:cholesterol ratio, angina, sex, blood pressure and four psychosocial characteristics (i.e. social support, work stress, life events and Type A behavior). It was found that the psychosocial factors improved the preoperative predictive power of significant coronary artery disease on four criteria: previous history of hypertension, previous history of myocardial infarction, signs of peripheral vascular disease and ECG evidence of myocardial infarction.

Preoperative prediction of significant coronary artery disease in patients with valvular heart disease

A prognostic index for predicting significant coronary artery disease was established using multiple logistic regression analysis of clinical data from 643 patients with valvular heart disease who had undergone routine coronary arteriography before valve replacement. The index or equation obtained incorporated the presence of angina, a family history of ischaemic heart disease, age, cigarette smoking habits, mitral valve disease, sex, and electrocardiographic evidence of myocardial infarction. The equation was validated using prospective data from 387 patients with valvular disease and shown to enable almost a third of routine coronary arteriograms to be omitted while maintaining 95% sensitivity for patients with coronary artery disease. Similar analysis of the more detailed prospective data produced a second discriminant function incorporating diastolic blood pressure, total cigarettes smoked in life, the severity of angina, family history of ischaemic heart disease, age, current cigarette smoking habits, and the ratio of total to high density lipoprotein cholesterol. This method improved the discrimination between patients with and without coronary artery disease, allowing omission of 30% of routine coronary arteriograms with 100% sensitivity for patients with coronary disease and omission of 41% with a 96% sensitivity level.