Myocardial Infarction Odds Ratio Research Articles

Folate, homocysteine levels, methylenetetrahydrofolate reductase (MTHFR) 677C → T variant, and the risk of myocardial infarction in young women: effect of female hormones on homocysteine levels

In young women data are limited about the association between myocardial infarction (MI) and hyperhomocysteinemia, low folate or methylenetetrahydrofolate reductase (MTHFR) genotypes. The effect of oral contraceptive (OC) use on plasma homocysteine levels is not clear. We assessed the association between hyperhomocysteinemia, low folate, MTHFR 677TT mutation and risk of MI, and we investigated the effect of OC use on homocysteine levels in controls. In 181 patients with a first MI and 601 controls 18-49 years of age from a population-based case-control study, non-fasting blood samples were available. The homozygote mutant allele (TT) was detected in 12% of the patients and in 10% of controls. The odds ratio (OR) for MI in TT patients compared with the wild-type (CC) controls was 1.3 [95% confidence interval (CI) 0.8, 2.3]. For all MTHFR genotypes combined, the OR for MI in the lowest quartile of folate (<5.4 nmol L-1) compared with the highest quartile (>10.4 nmol L-1) was 3.0 (95% CI 1.7, 5.1). A 2-fold increased risk of MI was found in women with the TT genotype who had folate levels below the median of 7.4 nmol L-1 compared with CC genotype and folate levels above the median (OR = 2.0; 95% CI 1.0, 3.7). Mean homocysteine levels were 12.2 micromol L-1 in OC users and 12.3 micromol L-1 in non-users. Only at the 97.5 percentile (cut-off 21.0 micromol L-1) was the adjusted OR for higher vs. lower homocysteine levels increased by 2.8-fold (95% CI 1.2, 6.8). Low folate is a risk factor for MI, particularly in women with the MTHFR 677TT genotype. Homocysteine levels were not influenced by OC use.

LOW JOB CONTROL AS A RISK FACTOR OF MYOCARDIAL INFARCTION FOR SENIOR OFFICIALS AND MANAGERS IN KAUNAS, LITHUANIA

Introduction Studies in Western societies have demonstrated that low job control according to the Karasek's demand-control model predicts myocardial infraction among men. Traversing the East-West boundaries we used the Swedish version of the demand-control questionnaire to assess the effect of low job control on first myocardial infarction risk in the male occupational categories in Kaunas, Lithuania, a country with quite different socioeconomic structure. Methods We conducted a case-control study among men aged 25–64 in Kaunas in 2001–2002. Cases were 203 men with a first non-fatal myocardial infarction and controls were 287 men in the same age group randomly selected from the study base. We used the International Standard Classification of Occupations (ISCO)-1991 to classify various occupations into 10 occupational categories. Logistic regression analysis was used for an estimation of the odds of developing myocardial infarction in relation to self-reported job demands and job control and the contribution of these factors together with standard risk factors to the estimated myocardial infarction risk in differnt occupational categories. Results We found that senior officials and managers (1-st ISCO category) were at increased myocardial infarction risk as compared to craft and related trades workers (7th ISCO category) (OR = 1.93 95% CI 1.07–3.49). The age-adjusted odds ratio of myocardial infarction in relation to low job control for the 1-st ISCO category was 2.61 (95% CI 1.70–4.01). Further adjustment for standard risk factors as smoking, arterial hypertension, obesity, and socioeconomic status decreased the risk to 2.02 (95% CI 0.89–4.52). Conclusions Low job control was a risk factor of myocardial infarction for the occupational category of senior officials and managers (1-st ISCO category) in Kaunas, Lithuania, a country in a transition market economy. Our study showed that the relation between psychosocial factors at work in terms of low job control is not restricted to Western societies but applies equally to Central and Eastern European societies that are currently subject to rapid socioeconomic transformation.

Multivitamin Supplements Are Inversely Associated with Risk of Myocardial Infarction in Men and Women—Stockholm Heart Epidemiology Program (SHEEP)

Epidemiologic data relating multivitamin supplement use to the risk of cardiovascular disease are sparse and inconsistent. We examined the association between self-selected use of low dose multivitamin supplements and the risk of myocardial infarction (MI). Our results are based on data from a large population-based, case-control study of subjects aged 45-70 y residing in Sweden, a country in which consumption of fruits and vegetables is relatively low and foods are not fortified with folic acid. The study included 1296 cases (910 men, 386 women) with a first nonfatal MI and 1685 controls (1143 men, 542 women) frequency-matched to the cases by sex, age and hospital catchment area. Odds ratios (OR) and 95% CI were calculated from unconditional logistic regression models. Among controls, 57% of the women and 35% of the men used dietary supplements; corresponding figures for the cases were 42 and 27%, respectively. Of those taking supplements, 80% used multivitamin preparations. After adjustment for major cardiovascular risk factors, the OR of MI comparing regular users of supplements with nonusers were 0.79 (95% CI 0.63-0.98) for men and 0.66 (95% CI 0.48-0.91) for women. This inverse association was not modified by such healthy lifestyle habits as consumption of fruits and vegetables, intake of dietary fiber, smoking habits and level of physical activity, although never smoking appeared to outweigh the association in women. Findings from this study indicate that use of low dose multivitamin supplements may aid in the primary prevention of MI.

Prothrombotic coagulation defects and cardiovascular risk factors in young women with acute myocardial infarction.

We investigated the effect of prothrombotic coagulation defects in combination with smoking and other conventional risk factors on the risk of myocardial infarction in young women. In 217 women with a first myocardial infarction before the age of 50 years and 763 healthy control women from a population-based case-control study, factor V Leiden and prothrombin 20210A status were determined. Data on major cardiovascular risk factors and oral contraceptive use were combined with the presence or absence of these prothrombotic mutations, and compared between patients and controls. The overall odds ratio for myocardial infarction in the presence of a coagulation defect was 1.1 [95% confidence interval (CI) 0.6-1.9]. The combination of a prothrombotic mutation and current smoking increased the risk of myocardial infarction 12-fold (95% CI 5.7-27) compared with non-smokers without a coagulation defect. Among women who smoked cigarettes, factor V Leiden presence versus absence increased the risk of myocardial infarction by 2.0 (95% CI 0.9-4.6), and prothrombin 20210A presence versus absence had an odds ratio of 1.0 (95% CI 0.3-3.5). We conclude that factor V Leiden and prothrombin 20210A do not add substantially to the overall risk of myocardial infarction in young women. However, in women who smoke, the presence of factor V Leiden increased the risk of myocardial infarction twofold.

Effect of antidepressants and their relative affinity for the serotonin transporter on the risk of myocardial infarction.

Antidepressants, particularly selective serotonin reuptake inhibitors (SSRIs), attenuate platelet activation by depleting serotonin storage and may decrease risk of myocardial infarction (MI). These drugs differ in their affinity for the platelet serotonin transporter and therefore may vary in their effects on MI protection. A case-control study of first MI in patients aged 40 through 75 years was conducted among 36 hospitals in a 5-county area during a 3-year period. Case subjects were patients hospitalized with a first MI, and control subjects were randomly selected from the same geographic area. Detailed information regarding medication use and other clinical and demographic data were obtained by telephone interview. Among the 1080 cases and 4256 controls who participated, there were 223 users of antidepressants with high serotonin transporter affinity, all of which were SSRIs (paroxetine, fluoxetine, and sertraline). After adjustment with multivariable logistic regression for age, gender, race, education, physical activity, quantity of cigarettes smoked per day, body mass index, aspirin use, family history of MI, and history of diabetes, hypertension, or hypercholesterolemia, the odds ratio for MI among current users of antidepressants with high serotonin transporter affinity compared with nonusers was 0.59 (95% CI 0.39 to 0.91; P=0.02). Increasing serotonin transporter affinity was associated with reduced odds of MI among users of all SSRIs (P for trend <0.01) but not tricyclic (P=0.77) or atypical (P=0.70) antidepressants. There was no association detected between non-SSRI antidepressant use and MI. Increasing serotonin transporter affinity correlates with greater MI protection with SSRI but not other antidepressant exposure.

Myocardial infarction risk in relation to zinc concentration in toenails.

Zn is an essential mineral. The role of Zn in atherosclerosis is not clear. Epidemiological studies, which have reported contradictory results, are limited by the use of serum Zn levels as a marker of intake. We assessed the association of toenail Zn, which integrates dietary Zn intake over 3 to 12 months, with the risk of a first myocardial infarction. Toenail Zn concentrations were determined by neutron activation analysis in the European multi-centre case-control study on antioxidants, myocardial infarction and breast cancer. This multi-centre case-control study included 684 cases and 724 controls from eight European countries and Israel. Toenail Zn levels of controls (adjusted for age and study centre) were positively associated with age, alpha-tocopherol and Se, but not with additional dietary variables or with classical risk factors for CHD. Average toenail Zn was 106.0 mg/kg in cases (95 % CI 103.1, 108.9) and 107.5 mg/kg in controls (95 % CI 104.5, 110.7). After controlling for cardiovascular risk factors and for centre, the adjusted odds ratios of myocardial infarction for quintiles 2-5 of toenail Zn with respect to the first quintile were 0.97 (95 % CI 0.59, 1.58), 1.15 (95 % CI 0.72, 1.85), 0.91 (95 % CI 0.56, 1.50), and 0.85 (95 % CI 0.52, 1.39). The P for trend was 0.45. In conclusion toenail Zn levels (reflecting long-term dietary intake) were not significantly associated with acute myocardial infarction.

Calcium channel blockers and myocardial infarction: a case--control study in a Japanese hospital.

To examine the relationship of the use of calcium channel blockers (CCBs) in hypertensive patients to myocardial infarction in Japan, where CCBs are prescribed much more frequently than in Europe and America. We conducted a nested case-control study using a hospital information system in Japan. Cases were hypertensive patients who were repeat visitors to Tokyo University Hospital as of April 1996 and had an incidence of fatal or non-fatal myocardial infarction between 1996 and 1999. Controls were hypertensive patients individually matched to cases by sex, age and history of angina pectoris. The study consisted of 16 cases, who were matched to 80 controls. Of the 80 control patients, 54 (68%) received CCBs. On the other hand, all but one of 16 cases received CCBs and the crude odds ratio of myocardial infarction associated with the use of calcium channel blockers was as high as 7.0 (0.9-55.3). The odds ratio was reduced to 4.9 (0.6-42.4) when adjusted by diabetes and diastolic blood pressure. Although the crude odds ratio of myocardial infarction associated with CCBs was high, the ratio was reduced when adjusted by known confounding factors, suggesting a mechanism of confounding by indication. In addition, the results obtained in this study using records from a single hospital should not be generalized.

Mediterranean diet and reduction in the risk of a first acute myocardial infarction: an operational healthy dietary score.

Although an important secondary prevention trial reported an impressive protection by a Mediterranean dietary pattern on reinfarction and cardiovascular death, scarce direct epidemiologic evidence is currently available regarding the role of the Mediterranean diet in the aetiology of coronary heart disease. The aim of the study was to quantify the risk reduction of incident myocardial infarction provided by a Mediterranean dietary pattern. We included 342 subjects (171 patients who suffered their first acute myocardial infarction and 171 matched controls) in a case-control study. A validated semi-quantitative food frequency questionnaire (136 items) was used. We defined an a priori Mediterranean dietary pattern. We assessed six food items that we considered protective: 1) olive oil, 2) fiber, 3) fruits, 4)vegetables, 5) fish and 6) alcohol. For each of these six dietary factors, we calculated the distribution according to quintiles within the study and assigned each participant a score of 1 to 5 corresponding to the quintile of intake, with 1 representing the lowest and 5 representing the highest quintile. We also estimated the quintiles of two other elements assumed to be associated with a higher risk: 7) meat/meat products and 8) some items with high glycaemic load (white bread, pasta and rice). For these two elements we inversely ranked the score, with 1 representing the highest and 5 representing the lowest quintile. Finally, we summed up the eight quintile values for each participant.A second score ( post hoc pattern) was built using only a single cut-off point for these eight elements. The cut-off points for each element in this post hoc pattern were decided according to the dose-response relationships between the consumption of each food item and the risk of myocardial infarction observed in the analyses that used quintiles of each food item. For both patterns, we found that the higher the score, the lower the odds ratio of myocardial infarction. A significant linear trend was apparent after adjustment for the main cardiovascular risk factors. For each additional point in the a priori Mediterranean pattern (observed range: 9-38) the odds ratio (95 % confidence intervals) was 0.92 (0.86-0.98). This estimate was 0.55 (0.42-0.73) when we used the post hoc pattern (range: 0-8). Our data support the hypothesis that a Mediterranean diet (that emphasizes olive oil, fiber, fruits, vegetables, fish and alcohol and reduces meat/meat products) can be an effective measure for reducing the risk of myocardial infarction. However, our results support the exclusion of refined cereals with a high glycaemic load as healthy elements of this pattern.

Serotonin transporter gene polymorphism and myocardial infarction: Etude Cas-Témoins de l'Infarctus du Myocarde (ECTIM).

Depression is a risk factor for myocardial infarction (MI). Selective serotonin reuptake inhibitors reduce this risk. The site of action is the serotonin transporter (SLC6A4), which is expressed in brain and blood cells. A functional polymorphism in the promoter region of the SLC6A4 gene has been described. This polymorphism may be associated with the risk of MI. The SLC6A4 polymorphism has been investigated by polymerase chain reaction in 671 male patients with MI and in 688 controls from the Etude Cas-Témoins de l'Infarctus du Myocarde (ECTIM) multicentric study. Percentages for LL, LS, and SS genotypes were 35.5%, 45.4%, and 19.1%, respectively, for cases versus 28.1%, 49.1%, and 22.8%, respectively, for controls. S allele frequency was 41.8% and 47.4% for cases and controls, respectively. After adjustment for age and center by using multivariable logistic regression, the odds ratio for MI associated with the LL genotype was 1.40 (95% CI 1.11 to 1.76, P=0.0047). The LL genotype of the SLC6A4 polymorphism is associated with a higher risk of MI. This could be attributable to the effect of the polymorphism on serotonin-mediated platelet activation or smooth muscle cell proliferation or on other risk factors, such as depression or response to stress.

Oral Contraceptives and the Risk of Myocardial Infarction

Some but not all studies claim an association between oral contraceptive (OC) use and the risk of myocardial infarction (MI). The present study sought to determine whether low-dose combined OC preparations influence the risk of MI. Variables considered were the type of progestogen in third-generation OCs (desogestrel or gestodene) and second-generation OCs (levonorgestrel), the estrogen dose, and the presence or absence of prothrombotic mutations (factor V Leiden and the G20210A mutation in the prothrombin gene). The study group included 248 women 18 to 49 years of age who were hospitalized with a first MI during the years 1990-1995 and 925 control women who lacked a history of coronary, cerebral, or peripheral arterial disease. Patients and control women had mean ages of 43 and 38 years, respectively. The patients more frequently had major risk actors for cardiovascular disease. Women using any type of OC were at twice the risk of MI as were control women after adjusting for age, calendar year, and area of residence. Odds ratios increased in most age categories after further adjustment for possible confounding factors. Nonsmoking OC users without hypertension, high cholesterol, or diabetes had a relative risk of MI of 3.1. Both patients and control subjects had used OCs for a median of 10 years. The odds ratio for MI was 2.8 in women using first-generation OCs (compared with nonusers), 2.4 for those using second-generation OCs, and 1.3 for users of third-generation preparations. Similar results were obtained analyzing only users of second- and third-generation OCs containing 30 pg of ethinyl estradiol. Similar odds ratios were found for third-generation OCs containing desogestrel or gestodene. An impressive odds ratio of 13.6 was found for women who smoked and had used OCs. The odds ratio for MI in women having a prothrombotic mutation was 1.1. This case-control study shows that using current combined OCs increases the overall risk of a first MI. The risk is not great in absolute terms, but it should have a substantial effect on women's health because 35% to 45% of reproductive-aged women use OCs. Screening for conventional cardiovascular risk factors is appropriate before prescribing an oral contraceptive.

High expressor paraoxonase PON1 gene promoter polymorphisms are associated with reduced risk of vascular disease in younger coronary patients

Human paraoxonase-1 is hypothesised to protect serum lipoproteins from oxidative stress. Decreased serum activity of paraoxonase-1 in animal models is associated with an increased risk of vascular disease and has been linked to the anti-oxidant capacity of the enzyme. Promoter polymorphisms of the human paraoxonase-1 gene strongly influence serum concentrations of the enzyme. The present study examined the hypothesis that promoter polymorphisms may be genetic risk factors for vascular disease in man. Genotypes arising from the promoter C(-907)G polymorphism were analysed in the ECTIM2 population. The global odds ratio for myocardial infarction, comparing the high expressor GG genotype to other genotypes, was 0.77 (0.61–0.97) ( P=0.024). The association with the promoter genotype was more pronounced in the youngest age group (odds ratio 0.52 (0.31–0.87), P=0.012) and was progressively lost with age (respectively 50 years to <60 years, P=0.26; >60 years, P=0.45). There was no association between the promoter genotypes and serum lipids. The data are consistent with the high expressor promoter genotype being linked to reduced risk of myocardial infarction. The influence of the genotype may be compromised in older patients.

Coronary calcification detected by electron-beam computed tomography and myocardial infarction. The Rotterdam Coronary Calcification Study.

Available data are insufficient to determine the relation between coronary calcification and coronary events in the general population. We cross-sectionally examined the association between coronary calcification and myocardial infarction in the prospective Rotterdam Coronary Calcification Study. From 1997 onwards, subjects were invited for electron-beam computed tomography scanning to detect coronary calcification. The study was embedded in the population-based Rotterdam Study. Calcifications were quantified in a calcium score according to Agatston's method. Calcium scores were available for 2,013 participants with a mean age of 71 years (standard deviation, 5.7 years). A history of myocardial infarction prior to scanning was present in 229 subjects. Compared to subjects in the lowest calcium score category (0-100), the age-adjusted odds ratio for myocardial infarction in subjects in the highest calcium score category (above 2,000) was 7.7 (95% confidence interval, 4.1-14.5) for men, and 6.7 (95% confidence interval, 2.4-19.1) for women. Additional adjustment for cardiovascular risk factors only slightly altered the estimates. The association was observed across all age subgroups, i.e. also in subjects of 70 years and older. A strong and graded association was found between coronary calcification and myocardial infarction. The association remained at high ages.

Asociación de factores lipídicos, genotipo de APOE y tipos de mutación del gen del receptor de LDL con el infarto agudo de miocardio en sujetos con hipercolesterolemia familiar heterocigota

Our goal was to analyze the relationship of lipids and lipoproteins, APOE genotype and mutations of the LDL receptor gene with the prevalence of myocardial infarction (MI) in patients with familial hypercholesterolemia (FH) from a Southern European FH population. We studied 108 heterozygous FH subjects aged > 35 years (41 males). It was a cross-sectional study comparing individuals with FH and MI with individuals with FH without MI. In 88 FH subjects, a mutation of the LDL receptor gene was detected. These FH subjects were divided in carriers of null mutation or no null mutations. We compared lipids and lipoproteins and prevalences of LDL receptor type mutation and APOE genotype. Parameters associated with MI were: age, presence of xanthomas and arcus cornealis, plasma concentrations of total cholesterol (TC), LDLc, TC/HDLc ratio > 5.3 and *4 genotype of the APOE gene. Odds ratio for MI were as follows: presence of xanthomas and arcus cornealis, 1.36 (CI 95%, 1.08-1.71; P = 0.01), age > 54 years (50 th of FH group), 1.56 (CI 95%, 1.19-2.04; P = 0.001) and plasma TC values > 332 mg/dl (50 th of FH group), 1.34 (CI 95%, 1.05-1.71; P = 0.019). In the logistic regression model, only age and TC were significantly associated with MI. In FH subjects aged over 35 years from a Southern European population, MI is associated with age, plasma TC and LDLc values, TC/HDLc ratio and the *4 genotype. In addition, MI is related with age and TC plasma levels on an independent basis.

Oral contraceptives and the risk of myocardial infarction.

An association between the use of oral contraceptives and the risk of myocardial infarction has been found in some, but not all, studies. We investigated this association, according to the type of progestagen included in third-generation (i.e., desogestrel or gestodene) and second-generation (i.e., levonorgestrel) oral contraceptives, the dose of estrogen, and the presence or absence of prothrombotic mutations In a nationwide, population-based, case-control study, we identified and enrolled 248 women 18 through 49 years of age who had had a first myocardial infarction between 1990 and 1995 and 925 control women who had not had a myocardial infarction and who were matched for age, calendar year of the index event, and area of residence. Subjects supplied information on oral-contraceptive use and major cardiovascular risk factors. An analysis for factor V Leiden and the G20210A mutation in the prothrombin gene was conducted in 217 patients and 763 controls The odds ratio for myocardial infarction among women who used any type of combined oral contraceptive, as compared with nonusers, was 2.0 (95 percent confidence interval, 1.5 to 2.8). The adjusted odds ratio was 2.5 (95 percent confidence interval, 1.5 to 4.1) among women who used second-generation oral contraceptives and 1.3 (95 percent confidence interval, 0.7 to 2.5) among those who used third-generation oral contraceptives. Among women who used oral contraceptives, the odds ratio was 2.1 (95 percent confidence interval, 1.5 to 3.0) for those without a prothrombotic mutation and 1.9 (95 percent confidence interval, 0.6 to 5.5) for those with a mutation The risk of myocardial infarction was increased among women who used second-generation oral contraceptives. The results with respect to the use of third-generation oral contraceptives were inconclusive but suggested that the risk was lower than the risk associated with second-generation oral contraceptives. The risk of myocardial infarction was similar among women who used oral contraceptives whether or not they had a prothrombotic mutation.

The -1185 A/G and -1051 G/A dimorphisms in the von Willebrand factor gene promoter and risk of myocardial infarction.

Elevated plasma von Willebrand factor (VWF) levels are associated with coronary artery disease, although the precise mechanism for this is unclear. Recently, four linked dimorphisms in the VWF gene promoter were demonstrated to influence plasma VWF level. We conducted a case-control study of 525 acute myocardial infarction (MI) cases and 451 control subjects, all aged < or = 75 years, to assess the potential contribution of two of these dimorphisms (-1185 G/A and -1051 A/G) to the risk of MI. The frequency of the -1185A/-1051G haplotype, associated with elevated VWF levels, was similar in the case and control groups, yielding a haplotypic odds ratio for MI of 0.93 (95% CI 0.77, 1.12, P = 0.43), and there was no significant association between the -1185A/-1051G haplotype and the risk of MI in any subgroup analysed. We therefore conclude that possession of the -1185A/-1051G haplotype does not confer an increased risk for MI.

Single nucleotide polymorphisms in multiple novel thrombospondin genes may be associated with familial premature myocardial infarction.

Recent advances in high-throughput genomics technology have expanded our ability to catalogue allelic variants in large sets of candidate genes related to premature coronary artery disease. A total of 398 families were identified in 15 participating medical centers; they fulfilled the criteria of myocardial infarction, revascularization, or a significant coronary artery lesion diagnosed before 45 years in men or 50 years in women. A total of 62 vascular biology genes and 72 single-nucleotide polymorphisms were assessed. Previously undescribed variants in 3 related members of the thrombospondin protein family were prominent among a small set of single-nucleotide polymorphisms that showed a statistical association with premature coronary artery disease. A missense variant of thrombospondin 4 (A387P) showed the strongest association, with an adjusted odds ratio for myocardial infarction of 1.89 (P=0.002 adjusted for covariates) for individuals carrying the P allele. A variant in the 3' untranslated region of thrombospondin-2 (change of thymidine to guanine) seemed to have a protective effect against myocardial in individuals homozygous for the variant (adjusted odds ratio of 0.31; P=0.0018). A missense variant in thrombospondin-1 (N700S) was associated with an adjusted odds ratio for coronary artery disease of 11.90 (P=0.041) in homozygous individuals, who also had the lowest level of thrombospondin-1 by plasma assay (P=0.0019). This large-scale genetic study has identified the potential of multiple novel variants in the thrombospondin gene family to be associated with familial premature myocardial infarction. Notwithstanding multiple caveats, thrombospondins specifically and high-throughput genomic technology in general deserve further study in familial ischemic heart disease.

Selective serotonin reuptake inhibitors and myocardial infarction.

Depression is an independent risk factor for myocardial infarction (MI). Selective serotonin reuptake inhibitors (SSRIs) may reduce this risk through attenuation of serotonin-mediated platelet activation in addition to treatment of depression itself. case-control study of first MI in smokers 30 to 65 years of age was conducted among all 68 hospitals in an 8-county area during a 28-month period. Cases were patients hospitalized with a first MI. Approximately 4 community control subjects per case were randomly selected from the same geographic area using random digit dialing. Detailed information regarding use of antidepressant medication as well as other clinical and demographic data were obtained by telephone interview. A total of 653 cases of first MI and 2990 control subjects participated. After adjustment, using multivariable logistic regression, for age, sex, race, education, exercise, quantity smoked per day, body mass index, aspirin use, family history of MI, number of physician encounters, and history of coronary disease, diabetes, hypertension, or hypercholesterolemia, the odds ratio for MI among current SSRI users compared with nonusers was 0.35 (95% CI 0.18, 0.68; P<0.01). Non-SSRI antidepressant users had a nonsignificant reduction in MI risk with wide confidence intervals (adjusted odds ratio 0.48, CI 0.17, 1.32; P=0.15). However, analysis of this group was limited by the small number of exposed subjects. The use of SSRIs may confer a protective effect against MI. This could be attributable to the inhibitory effect SSRIs have on serotonin-mediated platelet activation or possibly amelioration of other factors associated with increased risk for MI in depression.

Environmental tobacco smoke and myocardial infarction among never-smokers in the Stockholm Heart Epidemiology Program (SHEEP).

An increased risk for myocardial infarction (MI) related to environmental tobacco smoke (ETS) exposure has previously been reported, but several aspects of the association are still uncertain. We studied the MI risk associated with ETS exposure among 334 nonfatal never-smoking MI cases and 677 population controls, 45-70 years of age, in Stockholm County. A postal questionnaire with a telephone follow-up provided information on ETS exposure and other potential risk factors for MI. After adjustment for age, gender, hospital catchment area, body mass index, socioeconomic status, job strain, hypertension, diet, and diabetes mellitus, the odds ratio for MI was 1.58 (95% confidence interval = 0.97-2.56) for an average daily exposure of 20 cigarettes or more from the spouse. Combined exposure from spouse and work showed an increasing odds ratio for MI, up to 1.55 (95% confidence interval = 1.02-2.34) in the highest category of weighted duration, that is, more than 90 "hour-years" of exposure (1 "hour-year" = 365 hours, or 1 hour per day for 1 year). In addition, more recent exposure appeared to convey a higher risk. Our data confirm an increased risk of MI from exposure to ETS and suggest that intensity of spousal exposure, combined exposure from spouse and work, and time since last exposure are important.

Time urgency and risk of non-fatal myocardial infarction

Inconsistencies in the literature linking Type A behaviour pattern (TAB) to coronary heart disease (CHD) may be due to differences in the effects of various components of TAB, namely aggressiveness, hostility, ambitiousness, competitive drive, and a chronic sense of time urgency. We investigated the association between sense of time urgency/impatience and non-fatal myocardial infarction (MI) in a study of 340 cases and an equal number of age-, sex-, and community-matched controls. A dose-response relation was apparent among subjects who rated themselves higher on the four-item time urgency/impatience scale (P-value for trend <0.001), with a matched odds ratio (OR) for non-fatal MI of 4.45 (95% CI : 2.20-8.99) comparing those with the highest rating to those with the lowest. After further adjustment for family history of premature MI, physical activity, body mass index, occupation, cigarette smoking, total caloric intake, per cent calories from saturated fat, alcohol intake, lipid levels, treated hypertension and diabetes, the dose-response relation remained (P-value for trend = 0.015) and the adjusted OR for MI was 3.99 (95% CI : 1.32-12.0) comparing those with the highest rating to those with the lowest. In these data, a sense of time urgency/impatience was associated with a dose-response increase in risk of non-fatal MI, independent of other risk factors. Prospective cohort studies of time urgency/impatience and incident CHD events are needed to confirm or refute these observations from a case-control study.

Interleukin-6 gene polymorphisms and susceptibility to myocardial infarction: the ECTIM study. Etude Cas-Témoin de l'Infarctus du Myocarde.

There is growing evidence that interleukin (IL) 6 plays an important role in the atherosclerotic process because of its role in mediating immune and inflammatory responses and inducing cell proliferation. The present study examined whether molecular variations at the IL-6 locus are involved in the predisposition to myocardial infarction. The entire coding region, 1,158 bp of the 5' flanking region and 237 bp of the 3' flanking region of the IL-6 gene were screened. We detected three nucleotide substitutions in the 5' region at positions -174 (G/C), -572 (G/C), and -596 (G/A) from the transcription start site, and one insertion/deletion in the 3' region at position +528 after the Stop codon. These polymorphisms were genotyped in the Etude Cas-Témoin de l'Infarctus du Myocarde study comparing male patients (n=640) and age-matched controls (n=719) from Northern Ireland and France. The IL-6/G-174C and IL-6/G-596A polymorphisms were in nearly complete association. Carriers of the IL-6/-174 C allele were more frequent in patients than in controls. The population-adjusted odds ratio for myocardial infarction associated with genotype CC+CG vs. GG was estimated as 1.34. In French patients the number of coronary arteries with greater than 50% stenosis was assessed by angiography. The IL-6/-174 C allele was more frequent in patients with two or fewer stenosed vessels than in patients with three-vessel lesions. These results suggest that genetic variation at the IL-6 locus is associated with susceptibility to myocardial infarction, especially events occurring on less extended lesions. These findings would be compatible with a lower IL-6 secretion associated with the IL-6/-174 C allele, itself or in combination with other promoter polymorphisms, leading to more unstable plaques.