Risk factors for first-time acute myocardial infarction patients in Trinidad

Background

The relative importance of coronary artery disease (CAD) risk varies globally. The aim of this study was to determine CAD risk factors for acute myocardial infarction (AMI) among patients in public health care institutions in Trinidad using a case–control type study design.

Methods

The sample comprised 251 AMI patients hospitalized between March 1, 2011 and April 30, 2012 and 464 age- and sex-matched non-AMI patients with no terminal or life-threatening illness and who did not undergo treatment for CAD. SPSS version 19 was used for data analysis that included chi-square tests, unadjusted and adjusted odds ratios (OR) and conditional multiple binary logistic regression.

Results

There was no difference in age between AMI and non-AMI patients (p = 0.551). Chi-square test revealed that clinical and lifestyle variables including stressful life, diabetes, hypertension, hypercholesterolaemia, ischaemic heart disease (IHD), a family history of IHD (p ≤ 0.001), smoking (p = 0.007) and alcohol consumption (p = 0.013) were associated with AMI; sex (p = 0.441), ethnicity (p = 0.366), age group (p = 0.826) and renal failure (p = 0.487) were not.

Both unadjusted and adjusted (for age) ORs showed that the odds of hypertension, IHD and alcohol consumption were greater among AMI patients than among non-AMI patients for males; diabetes and IHD for females; and that the odds of a stressful life was greater among non-AMI patients and were the same for both groups with respect to sex, age > 45 years, hypercholesterolemia, renal insufficiency, and family history of IHD.

Conditional multiple logistic regression showed that smoking [OR: 0.274, p ≤ 0.001, 95% CI for OR (0.140, 0.537)], a stressful life [OR: 2.697, p ≤ 0.001, 95% CI for OR (1.585, 4.587)], diabetes [OR: 0.530, p = 0.020, 95% CI for OR (0.310, 0.905)], hypertension [OR: 0.48, p = 0.10. 95% CI for OR (0.275, 0.837)] and IHD [OR: 0.111, p ≤ 0.001, 95% CI for OR (0.057, 0.218)] were the only useful AMI predictors.

Conclusions

Smoking, diabetes, hypertension, IHD and decrease stress are useful AMI predictors.

Relation of serum total cholesterol and other factors to risk of cerebral infarction in Japanese men with hypercholesterolemia

BACKGROUND

Risk factors for cerebral infarction have not been well clarified, except for hypertension (HT), and few studies have examined the risk factors in the elderly.

METHODS AND RESULTS

Clinical and behavioral risk factors for cerebral infarction were examined in 4,349 Japanese men aged 45-74 years with a serum total cholesterol (TC) concentration of 220 mg/dl or greater who participated in the Kyushu Lipid Intervention Study. A total of 81 men developed definite cerebral infarction in a 5-year follow-up period. The Cox proportional hazards model was used with serum TC at baseline and during the follow-up, serum high-density lipoprotein-cholesterol (HDL-C), HT, diabetes mellitus (DM), and other factors as covariates. Serum TC during the follow-up, not at baseline, was positively associated with cerebral infarction, showing a stronger association in the elderly (>or=65 years old) than in the middle-aged (<65 years old). Statin use was related to a moderate decrease in the risk of cerebral infarction when follow-up TC was not considered, but the decrease was almost nullified after adjustment for follow-up TC. A low concentration of serum HDL-C, diabetes mellitus, hypertension, and angina pectoris were each related to an increased risk. No clear association was observed for body mass index, smoking or alcohol use.

CONCLUSIONS

Lowering cholesterol is important in the prevention of cerebral infarction in men with moderate hypercholesterolemia. A low concentration of HDL-C, DM, and HT are independent predictors of cerebral infarction.

Past history of obesity (overweight by WHO criteria) is associated with an increased risk of nonfatal acute myocardial infarction: a case-control study in Japan

BACKGROUND

Obesity is an important risk factor for the occurrence of coronary artery disease (CAD) in Western countries and furthermore, it often coexists with other CAD risk factors such as hypertension, dyslipidemia and diabetes mellitus. However, it is uncertain whether obesity is a CAD risk factor in Japan because Japanese are relatively thin on average.

METHODS AND RESULTS

The CAD risk associated with obesity (body mass index > or =25.0) 10 years before as well as at the time of the survey was assessed in a case - control study of acute myocardial infarction (AMI), which compared 660 AMI patients aged 40-79 years and 1,277 community controls, matched to each case by sex, year of birth, and residence. The prevalence of current obesity did not show any material difference between cases and controls, but compared with controls, past obesity was much more frequent in cases. Even after controlling for other CAD risk factors, past obesity was associated with a 2-fold increase in the risk of AMI. Past obesity was associated with an increased risk of AMI even without current obesity.

CONCLUSION

Past obesity is a CAD risk, even after weight reduction.

Relation of Serum Total Cholesterol and Other Risk Factors to Risk of Coronary Events in Middle-Aged and Elderly Japanese Men With Hypercholesterolemia-The Kyushu Lipid Intervention Study-

BACKGROUND

The role of serum total cholesterol (TC) in the development of coronary heart disease (CHD) may differ in different age groups.

METHODS AND RESULTS

The relation of serum TC and other risk factors to CHD events was examined in middle-aged (<65 years) and elderly (> or =65 years) men separately in the Kyushu Lipid Intervention Study (KLIS). Subjects were 4,349 men aged 45-74 years with serum TC of 220 mg/dl or greater who had no history of myocardial infarction, coronary angioplasty, or stroke. There were 123 CHD events (ie, myocardial infarction, coronary bypass surgery, coronary angioplasty, cardiac death, and sudden death) in a 5-year follow-up period. The Cox proportional hazards model was used with baseline and follow-up serum TC, baseline high-density lipoprotein (HDL) cholesterol, hypertension, diabetes mellitus, and other factors as covariates. Serum TC concentration during the follow-up, not at baseline, was associated with an increased risk of CHD events, especially in elderly men. High concentrations of serum HDL cholesterol were associated with a modest, statistically nonsignificant decrease in the risk among middle-aged men. An increased risk of CHD events associated with diabetes mellitus was greater in middle-aged men. Hypertension and smoking were not measurably related to the risk in either middle-aged or elderly men.

CONCLUSIONS

Both the serum TC concentration during follow-up and diabetes mellitus are important predictors of CHD events in Japanese men with moderately elevated serum TC.

Reduction in serum total cholesterol and risks of coronary events and cerebral infarction in Japanese men: the Kyushu Lipid Intervention Study

Lowering serum total cholesterol is shown to decrease the risk of coronary heart disease (CHD) in Western countries,but evidence is limited regarding cerebral infarction (CI). The present study used the Kyushu Lipid Intervention Study to examine the risks of CHD events and CI in relation to reduction in serum total cholesterol. Subjects were 4,615 men aged 45-74 years with serum total cholesterol of 220 mg/dl (5.68 mmol/L) or greater who had no history of CHD events or stroke. CHD events and CI numbered 125 and 92, respectively, in a 5-year follow-up. After adjustment for potential confounding factors, the relative risks of CHD events and CI for 15% or greater reduction in total cholesterol, compared with less than 5% reduction, were 0.78 (95% confidence limit [CL]0.46-1.32) and 0.39 (95% CL 0.22-0.69), respectively. As compared with on-treatment cholesterol levels of 240 mg/dl (6.20 mmol/L)or higher, the risk of CHD events was approximately 50% lower across 3 categories below 240 mg/dl (6.20 mmol/L), and that of CI was 70%lower at 2 categories below 220 mg/dl (5.68 mmol/L). Lowering serum total cholesterol below 220 mg/dl (5.68 mmol/L) seems desirable with regard to the prevention of CI.

Pravastatin Reduces the Incidence of Cardiac Events Among Patients With Myocardial Infarction

We retrospectively compared the incidence of cardiac events in myocardial infarction (MI) patients treated in our departments between 1990 and 1999 with pravastatin or without cholesterol-lowering agents. Our aim was to evaluate the efficacy of pravastatin in the secondary prevention of MI. Cardiac events--defined as fatal or nonfatal recurrent MI, sudden cardiac death, and death from congestive heart failure--occurred in 8 (2.2%) of 356 MI patients treated with pravastatin (17.1 cases/1.000 person x year) and in 39 (5.6%) of 700 MI patients not treated with cholesterol-lowering agents (54.3 cases/1000 person x year), which represented a significant decline among those taking pravastatin (P < 0.05, odds ratio: 0.39, 95% (CI: 0.18-0.84). Likewise, total mortality was significantly lower among patients treated with pravastatin (18 cases, 5.1%; 38.4 cases/1,000 person x year vs 77 cases, 11.0%; 107.2 cases/1,000 person x year, P < 0.01, odds ratio: 0.43, 95% CI: 0.25-0.73). Subgroup analysis revealed a significantly lower incidence or cardiac events in the pravastatin group for 6 of the items among 53 patient characteristics, and was lower but not significant for 45 items and was greater but not significant only for 2 items. Furthermore, multivariate analysis confirmed pravastatin to be a useful factor for preventing the occurrence of cardiac events in MI patients (P < 0.05, odds ratio: (0.44, 95% CI: 0.20-0.95), and Kaplan-Meier curves also showed pravastatin to significantly reduce the incidence of both cardiac events and total mortality. These findings are consistent with those previously reported by several large-scale clinical trials carried out in Western countries, and demonstrate that pravastatin is useful for secondary prevention of MI in Japanese patients.