Biomedical subjects

J D Kark

Publications and source records attributed to J D Kark.

At least 37 records · Page 2Linked to original sources

PubMed1998

Familial aggregation of heart rate variability based on short recordings--the kibbutzim family study.

The objective of this study was to assess the familial aggregation of heart rate variability (HRV), a readily measurable noninvasive reflection of cardiac autonomic function. Familial correlations were analyzed in 451 kibbutz members aged 15-97 years belonging to 80 kindreds. Five-minute duration Holter recordings made during silent supine spontaneous breathing and metronomic breathing were analyzed in the time and frequency domains. The present analysis considers the familial correlations and the heritability estimates of two time-domain indices, the standard deviation (SD) of the R-R interval (RR), reflecting total variability, and the root mean square of successive differences in RR intervals (RMSSD), reflecting vagal (parasympathetic) tone. During free breathing, age- and sex-adjusted correlations between parents and their children (r=0.24 for both indices) and between adult siblings above 30 years of age (r=0.24 and t=0.34 for SD and RMSSD, respectively) were statistically significant, whereas spouse correlations (r=-0.04, r=-0.02 for SD and RMSSD, respectively) and correlations in younger siblings (r=-0.22 and r=0.01, respectively) were not. Significant heritability estimates were demonstrated for the two indices (h2=0.41 for SD and h2=0.39 for RMSSD). These findings suggest that familial aggregation of HRV characteristics is determined mostly by genetic factors and less so by environmental factors and provide a basis for continuing the investigation into the underlying genetic influences on HRV.

Adolescent↗

PubMed1998

Five minute recordings of heart rate variability for population studies: repeatability and age-sex characteristics.

OBJECTIVE: To evaluate the stability of short recordings of heart rate variability (HRV) with time, and the association of HRV with age and sex. DESIGN: Five minute Holter recordings were made twice over a two month interval (tracking study). In addition, HRV was measured in a cross sectional study. SETTING: Residents of 11 Israeli kibbutzim were examined in their settlements. SUBJECTS: 32 men and 38 women (aged 31-67) participated in the tracking study and 294 (aged 35-65) were involved in the cross sectional study. MAIN OUTCOME MEASURES: Time and frequency domain analyses on Holter recordings were undertaken in two breathing conditions: spontaneous and controlled breathing (15 respirations per minute). Regression was used to assess the relations of sex, age, heart rate, and logarithmically transformed HRV indices. RESULTS: HRV measures were highly consistent with time with correlations of 0.76-0.80 for high frequency and total power. Geometric mean total power declined with age by 45% in men and 32% in women, and was lower by 24% among women than among men (all p < or = 0.005). Men had a 34% higher very low and low frequency power and a higher ratio of low to high frequency power (p < 0.001). Conversely, high frequency power in women represents a greater proportion of total power than in men. CONCLUSION: Short recordings of HRV in a non-laboratory setting are stable over months and therefore characteristic of an individual. Strong age and sex effects were evident. HRV derived from short recordings can be informative in population based studies.

Adult↗

PubMed1997

Lycopene and myocardial infarction risk in the EURAMIC Study.

A multicenter case-control study was conducted to evaluate the relations between antioxidant status assessed by biomarkers and acute myocardial infarction. Incidence cases and frequency matched controls were recruited from 10 European countries to maximize the variance in exposure within the study. Adipose tissue needle aspiration biopsies were taken shortly after the infarction and analyzed for levels of carotenoids and tocopherols. An examination of colinearity including all covariates and the three carotenoids, alpha-carotene, beta-carotene, and lycopene, showed that the variables were sufficiently independent to model simultaneously. When examined singularly, each of the carotenoids appeared to be protective. Upon simultaneous analyses of the carotenoids, however, using conditional logistic regression models that controlled for age, body mass index, socioeconomic status, smoking, hypertension, and maternal and paternal history of disease, lycopene remained independently protective, with an odds ratio of 0.52 for the contrast of the 10th and 90th percentiles (95% confidence interval 0.33-0.82, p = 0.005). The associations for alpha- and beta-carotene were largely eliminated. We conclude that lycopene, or some substance highly correlated which is in a common food source, may contribute to the protective effect of vegetable consumption on myocardial infarction risk.

Adipose Tissue↗

PubMed1997

Association between toenail selenium and risk of acute myocardial infarction in European men. The EURAMIC Study. European Antioxidant Myocardial Infarction and Breast Cancer.

The association between selenium status and risk of acute myocardial infarction was examined in a multicenter case-control study in 10 centers from Europe and Israel in 1991-1992. Selenium in toenails was assessed for 683 nonfatal male cases with first acute myocardial infarction and 729 controls less than 70 years of age. Median toenail selenium content was 0.553 microgram/g for cases and 0.590 microgram/g for controls. After adjustment for age, center, and smoking, the odds ratio for myocardial infarction in the highest quintile of selenium as compared with the lowest was 0.63 (95 percent confidence interval 0.37-1.07, p for trend = 0.08). The observed inverse trend was somewhat stronger when the authors adjusted for vitamin E status (p = 0.05). Analysis stratified for smoking habits showed an inverse association in former smokers (odds ratio for the 75th-25th percentile contrast = 0.63 (95 percent confidence interval 0.43-0.94)), but not in current smokers (odds ratio = 0.97 (0.71-1.32)) or in those who had never smoked (odds ratio = 1.55 (0.87-2.76)). Analysis stratified by center showed a significant inverse association between selenium levels and risk of myocardial infarction for Germany (Berlin) only (75th to 25th percentile odds ratio = 0.62 (95 percent confidence interval 0.42-0.91)), which was the center with the lowest selenium levels. It appears that the increased risk of acute myocardial infarction at low levels of selenium intake is largely explained by cigarette smoking; selenium status does not appear to be an important determinant of risk of myocardial infarction at the levels observed in a large part of Europe.

Case-Control Studies↗

PubMed1997

Chlamydia pneumoniae and acute myocardial infarction in Jerusalem.

BACKGROUND: A number of studies in European and North American populations have reported associations between Chlamydia pneumoniae seropositivity and coronary heart disease (CHD). Our objective was to assess the association of IgG and IgA antibodies to C. pneumoniae with acute myocardial infarction (MI) in a population-based case-control study in a Middle Eastern country. METHODS: Eligible cases aged 25-64 with a first acute MI were ascertained through an active surveillance system in Jerusalem hospitals between 1987 and 1989 (85% response). Controls were Jerusalem residents aged 25-64 sampled from the national population registry (83% response). Data on sociodemographic variables, CHD history and risk factors were collected by interview. Chlamydia serology, available for 93% of eligible participants, was performed by microimmunofluorescence on frozen stored samples using the TWAR antigen. Altogether, 251 male and 51 female cases, and 324 male and 162 female controls were analysed. RESULTS: Overall, high IgG titres (> or = 128) were not associated with increased risk of acute MI (Odds ratio [OR] = 0.74 for men [95% confidence interval (CI): 0.47-1.17] and 0.91 for women [95% CI: 0.43-1.94]); neither were high IgA titres (> or = 80) (OR = 1.11 for men [95% CI: 0.71-1.73] and 1.15 for women [95% CI: 0.33-4.0]). At IgG and IgA titres of > 32 and > 20 respectively there was also no relation. CONCLUSIONS: An association of C. pneumoniae seropositivity with acute MI was not confirmed in this population with a very high IgG seropositivity prevalence of 84% in males and 69% in females. However, we cannot exclude the possibility that a postulated recent outbreak obscured an association with chronic C. pneumoniae infection.

Adult↗

PubMed1996

A comparative study of four methods for analysing repeated measures data.

This paper compares four alternative statistical methods for the analysis of repeated measures data. The data set involves fatty acid composition of red blood cell membrane examined after acute MI and is characterized by a moderate sample size, unbalanced repeated measures and high within-individual correlations. Two methods are based on individual curve fitting and two on the random effects model. Results yielded by the four methods differed. The advantages and disadvantages of the methods are discussed. Assumptions required for the valid application of these methods are tested.

Analysis of Variance↗

PubMed1996

Does religious observance promote health? mortality in secular vs religious kibbutzim in Israel.

OBJECTIVES: This study assessed the association of Jewish religious observance with mortality by comparing religious and secular kibbutzim. These collectives are highly similar in social structure and economic function and are cohesive and supportive communities. METHODS: In a 16-year (1970 through 1985) historical prospective study of mortality in 11 religious and 11 matched secular kibbutzim in Israel, 268 deaths occurred among 3900 men and women 35 years of age and older during 41347 person-years of observation. RESULTS: Mortality was considerably higher in secular kibbutzim. Cox proportional hazards analysis was used to adjust for age and the matched design; rate ratios were 1.67 (95% confidence interval [CI]=1.17, 2.39) for men, 2.67 (95% CI=1.55, 4.60) for women, and 1.93 (95% CI=1.44, 2.59) overall. Kaplan-Meier survival analysis of birth cohorts confirmed the association. The lower mortality in religious kibbutzim was consistent for all major causes of death. CONCLUSIONS: Belonging to a religious collective was associated with a strong protective effect not attributable to confounding by sociodemographic factors. Elucidation of mechanisms mediating this effect may provide etiologic insights and leads for intervention.

Adult↗

PubMed1996

The prevalence of obesity and its changes over time in middle-aged and elderly men and women in Jerusalem.

OBJECTIVE: To study the prevalence and correlates of overweight and obesity in Jerusalem, and changes over a 15-17 year period. DESIGN: Two cross-sectional surveys in 1970 and in 1986, among residents aged 50 years and more in a defined neighbourhood. SUBJECTS: The study samples comprised 1267 individuals in 1970 and 1858 in 1986. RESULTS: In 1986, 33% of women and 16% of men were obese (BMI > or = 30.0 kg/m2). There was a decreasing trend in the prevalence of obesity with age among women, and in men there was no overall trend but the lowest prevalence was in the 75-84 age-group. Significant relationships with education and region of birth were observed in women only. Prevalence was lowest in the more educated and in women born in Europe and America. Subjects' self-appraisal and their report of physicians' diagnosis of health disorders, revealed a significantly higher prevalence of ill-health among obese people. In 1986 the mean body mass index and the prevalence of obesity were higher than in 1970, in both sexes and in almost all age groups. The prevalence rate of obesity (standardized by sex and age) was 21% in 1970 and 25% in 1986, the difference was statistically significant (p = 0.008). The age standardized prevalence rate in each sex was also higher in 1986 although statistically significant only in men (p = 0.037). CONCLUSION: A community study in Jerusalem revealed a high prevalence of overweight and obesity in 1986 in this middle-aged and elderly population; and a higher mean body mass index and an increased prevalence of obesity were found in 1986 than in 1970, in both sexes. The increased prevalence of obesity among men could not be explained by changes in the age, education and ethnic composition of the population. Among women, the possibility cannot be excluded that part of the increase in obesity was attributable to changes in the distribution of the population by region of birth.

Africa, Northern↗

PubMed1995

Iraqi missile attacks on Israel. The association of mortality with a life-threatening stressor.

OBJECTIVE: The imminent deadline for the 1991 Persian Gulf War and, subsequently, the 18 missile attacks by Iraq on Israel represented an unusual, short-term, life-threatening stressor for an entire nation. We studied mortality in Israel in January and February 1991 to determine whether excess deaths were precipitated on days of missile attacks. DESIGN: A time-series mortality study. SETTING: The state of Israel. PARTICIPANTS: All Israelis aged 25 years and older. MAIN OUTCOME MEASURE: Daily mortality by sex, age, region, underlying cause, and place of death. RESULTS: On January 18, 1991, the day of the first strike on Israeli cities, a 58% increment in total mortality occurred in the Israeli population (95% confidence interval [CI], 34% to 86%; P < .0001), a 77% excess (95% CI, 40% to 120%) in women and a 41% excess (95% CI, 10% to 79%) in men. This excess mortality occurred largely in the targeted Tel Aviv-central coastal plain and Haifa regions from cardiovascular causes and mainly out of hospital, significantly more so (P < .01) in women than men. Subsequently, on 16 attack days no overall excess was noted, yet a 10% increase in out-of-hospital deaths occurred. CONCLUSIONS: Likely explanations for the initial increase in mortality include acute emotional stress coupled with breathing difficulties induced by gas masks and extended stay in sealed rooms with resultant hypoxia in susceptible individuals. Women were more vulnerable than men. The absence of elevated total mortality in the subsequent attacks suggests a rapid adaptation to the circumstances surrounding the war. The policy of an unventilated sealed room may have been detrimental.

Adult↗

PubMed1995

Non-insulin-dependent diabetes mellitus and fasting glucose and insulin concentrations are associated with arterial stiffness indexes. The ARIC Study. Atherosclerosis Risk in Communities Study.

BACKGROUND: Cardiovascular diseases are the most common cause of disability and death among subjects with non-insulin-dependent diabetes mellitus (NIDDM). The atherosclerotic process begins during the prediabetic phase characterized by impaired glucose tolerance, hyperinsulinemia, and insulin resistance. In vitro studies have suggested that glucose and insulin can substantially alter the structure and function of the arterial wall and affect the development of atherosclerosis. METHODS AND RESULTS: We performed a cross-sectional study of the relation of arterial stiffness indexes with glucose tolerance and serum insulin concentrations. Several indexes of common carotid artery stiffness were assessed with noninvasive ultrasound methods in a biracial sample of 4701 men and women 45 to 64 years of age in the Atherosclerosis Risk in Communities (ARIC) Study. Arterial compliance (AC), stiffness index (SI), pressure-strain elastic modulus (Ep), and Young's elastic modulus (YEM) were calculated. YEM includes wall (intima-media) thickness and thus gives an estimate of arterial stiffness controlling for wall thickness. All indexes of arterial stiffness were higher with increasing concentrations of fasting glucose. This finding was consistent in both black and white examines and in both sexes. A 25% increase in fasting glucose (approximately 1 SD) was associated in nondiabetic white men with a 5.8% (95% CI, -9.6% to -1.9%; P = .004) decrease in AC and increases of 5.8% (95% CI, 2.0% to 9.7%; P = .002) in SI, 11.3% (95% CI, 6.9% to 15.9%; P < .001) in Ep, and 11.2% (95% CI, 6.2% to 16.6%; P < .001) in YEM. In nondiabetic white women, the corresponding predicted changes were a decrease of 15.0% (95% CI, -18.2% to -11.7%; P < .001) in AC and increases of 16.6% (95% CI, 12.5% to 20.8%; P < .001) in SI, 23.2% (95% CI, 18.4% to 28.2%; P < .001) in Ep, and 19.2% (95% CI, 14.0% to 24.7%; P < .001) in YEM. Glucose and insulin contributed synergistically to the increase in stiffness indexes. Insulin and triglycerides also had a synergistic association with stiffness indexes. CONCLUSIONS: Our findings are compatible with the view that persons with NIDDM or borderline glucose intolerance have stiffer arteries than their counterparts with normal glucose tolerance and that the decreased elasticity is independent of artery wall thickness. The joint effect of elevated glucose, insulin, and triglycerides can have a considerable impact on arterial stiffness and play an important role in the early pathophysiology of macrovascular disease in NIDDM.

Arteriosclerosis↗

PubMed1995

Adipose tissue isomeric trans fatty acids and risk of myocardial infarction in nine countries: the EURAMIC study.

Dietary isomeric trans fatty acids-mainly produced by hydrogenation of oils-are suspected of increasing the risk of coronary heart disease. Dietary trans fatty acid intake is reflected in the fatty acid composition of adipose tissue. In an international multicentre study in eight European countries and Israel (EURAMIC), adipose tissue aspiration samples were obtained from 671 men with acute myocardial infarction (AMI), aged 70 years or less, and 717 men without a history of AMI (controls). The proportion of fatty acids, including isomeric trans monoenoic fatty acids with 18 carbon atoms (C18:1), was determined by gas chromatography. Although there were considerable differences between countries in mean (SD) proportion of adipose tissue C18:1 trans fatty acids, there was no overall difference between cases (1.61 [0.92]%) and the controls (1.57 [0.86]%). The risk of AMI did not differ significantly from 1.0 over quartiles of adipose C18:1 trans fatty acids: the multivariate odds ratio was 0.97 (95% CI 0.56-1.67) for the highest versus lowest quartile. After exclusion of subjects from Spanish centres because they had far lower proportions of adipose trans fatty acids than subjects from other countries, there was a tendency to increased risk of AMI in the upper quartiles of C18:1 trans; however, the trend was not statistically significant. Our results reflect considerable differences between countries in dietary intake of trans fatty acids but do not suggest a major overall effect of C18:1 trans fatty acids on risk of AMI. We cannot exclude the possibility that trans fatty acids have a significant impact on risk of AMI in populations with high intake.

Adipose Tissue↗

PubMed1995

Association of fibrinolytic parameters with early atherosclerosis. The ARIC Study. Atherosclerosis Risk in Communities Study.

BACKGROUND: Thrombosis, provoked by a rupture of an atherosclerotic plaque, plays a crucial role in precipitating a coronary heart disease event. Its role at the early stage of atherosclerosis has, however, been unclear, but it has been hypothesized that thrombosis or defective fibrinolysis contributes to the progression of atherosclerotic lesions. METHODS AND RESULTS: We studied the association of plasminogen activator inhibitor antigen (PAI-1), tissue-type plasminogen activator antigen (TPA), and D-dimer with early atherosclerosis in a cross-sectional case-control study involving 457 pairs chosen from the biracial cohort of the Atherosclerosis Risk in Communities (ARIC) Study. As examined by B-mode ultrasound, patients (cases) had intima-media thickness of carotid arteries above the 90th percentile and control subjects had thickness below the 75th percentile of the ARIC cohort. Persons with a history of heart disease, stroke, or claudication were excluded from the case-control selection. PAI-1, TPA, and D-dimer were higher in patients than in control subjects (P < or = .001, Wilcoxon signed rank statistic). In conditional logistic regression analyses, the odds ratios of carotid atherosclerosis were, for PAI-1, for example, 1.22, 1.54, and 1.60 in the second, third, and fourth quartiles compared with the first quartile (P < .0001, test of linear trend, adjusting for age, systolic blood pressure, total cholesterol, acetylsalicylic acid use, and time of blood draw). Corresponding tests for D-dimer and TPA also showed an increasing trend (P < .0001). CONCLUSIONS: The findings support the hypothesis that thrombosis and fibrinolysis play a role at the early stage of the atherosclerotic process.

Arteriosclerosis↗

PubMed1995

Stability of red blood cell membrane fatty acid composition after acute myocardial infarction.

Questionnaire-based assessment of dietary intake may be invalidated in case-control studies by biases of recall, reporting or interviewing. Biomarkers, free of such biases, can be useful adjunct measures if they themselves are not affected by the event under investigation. Consequently, we studied the stability of the fatty acid composition of the red blood cell (RBC) membrane during a 1-week period, in 20 patients aged 40-74 years after an acute myocardial infarction (MI). Statistical analysis that accounted for a repeated measures design with missing data was undertaken for five fatty acids: C16:0, C18:1, C18:2, C20:5 and C22:6. All fatty acids showed change over the 7 day period. Individuals tended to maintain their relative ranking over time as reflected by correlations between time points of between 0.85 to 0.90, with the exception of C16:0 in which correlations were lower and inconsistent. Over the first 24 hr from admission all fatty acids except C20:5 showed evidence of a statistically significant change. However over the first 7 hr C18:1, C18:2, C20:5 and C22:6 exhibited stability whereas C16:0 altered. We conclude that the fatty acid composition of the RBC membrane appears to change soon after an acute MI. Consequently, case-control studies may be biased towards positive associations for C16:0 and inverse associations for C18:2 and C20:5, i.e. consistent with conventional predictions. However, if blood samples are drawn within 6 hr of admission, bias in estimation of C18:1, C18:2, C20:5 and C22:6 may be unimportant.

Adult↗

PubMed1995

High prevalence of antibodies to Chlamydia pneumoniae; determinants of IgG and IgA seropositivity among Jerusalem residents.

The prevalence of antibodies to Chlamydia pneumoniae was examined in a stratified random sample of 581 Jerusalem adult residents between August 1987 and March 1989. IgG and IgA titres were measured by microimmunofluorescence, and associations with smoking and socio-demographic variables were assessed. IgG antibodies were found in 84.5% (95% confidence interval (CI): 80.4-87.9) of men and 68.7% (95% CI: 61.6-75.0) of women (P < 0.0001 for sex difference), indicating a very high rate of exposure in this population. IgA antibodies, postulated to represent persistent infection, were present in 45.1% (95% CI: 40.1-50.2) of men and 23% (95% CI: 17.4-29.7) of women (P < 0.0001 for sex difference). Factors associated with IgG seropositivity included family size, education and social class. On the other hand age (in men) and smoking were associated with IgA seropositivity. These findings support the hypothesis that low socioeconomic status and household crowding may be predictive of exposure to or infection with this organism (IgG seropositivity), whereas they do not explain persistence of the infection putatively expressed as IgA seropositivity.

Adult↗

PubMed1995

The effect of using short versus detailed self-administered questionnaires on the estimate of illicit drug use among young adults.

We compared two study instruments in use in the Israel Defence Forces to ascertain the prevalence of illicit drug use: a short versus a detailed self-administered anonymous questionnaire. A relatively lower estimate of illicit drug use was found among subjects that answered the short questionnaire. The difference was noted for lifetime prevalence of illicit drug use for women but not for men (6.5% of women reported ever use of illicit drugs using the detailed questionnaire versus 2.1% of women using the short questionnaire, p = 0.002); for prevalence of infrequent illicit drug use (3.3% of men and 3.4% of women reported less than monthly use of illicit drugs using the detailed questionnaire versus 0.2% of men and none of the women with the short questionnaire; p = 0.004 and p < 0.001, respectively), but not for frequent use (i e monthly or more). There was no difference in the percent of subjects that admitted that they knew where to get drugs. We conclude that the short questionnaire in routine use for more than a decade is a useful instrument when compared with the detailed questionnaire, in that the yield of important information such as frequent illicit drug use is similar. This is achieved with the benefit of greater convenience and ease of application to large samples at a lower cost.

Journal Article↗

PubMed1995

Mortality in two Jewish populations--Montreal and Israel: environmental determinants of differences.

BACKGROUND: Mortality was compared in the Jewish populations of Montreal and Israel and the overall Canadian population, to investigate whether the Israeli pattern of low male mortality and relatively high female mortality is replicated among Jews living elsewhere. METHODS: In Montreal, death certificates were obtained from Jewish funeral homes (where all Jewish deaths are believed to be handled) for 1986-1990 and coded. RESULTS: All-cause cumulative mortality for ages 35-74 (CM), was exceedingly low in Montreal Jews, both in males (CM = 0.312, 95% confidence interval [CI]: 0.274-0.350) and females (CM = 0.202, 95% CI: 0.172-0.232), compared to all Canadians (CM = 0.425; 95% CI: 0.414-0.435 and 0.251; 95% CI: 0.243-0.253) and Israeli Jews (CM = 0.406; 95% CI: 0.379-0.434, and 0.299; 95% CI: 0.276-0.322), for males and females. Sex ratios (male:female) were 1.36, 1.54, and 1.69 for Israeli Jews, Montreal Jews, and Canadians, respectively. Differences were due mainly to substantially lower cumulative mortality from circulatory diseases in Montreal Jews (CM = 0.139, 0.043 versus 0.203, 0.125 in Israeli Jews and 0.199, 0.081 in Canadians, in males and females, respectively); these differences were all highly significant. Sex ratios for circulatory deaths were lowest in Israel (1.63), highest in Montreal (3.23) and intermediate in Canadians (2.47). Among men, the circulatory diseases mortality ratio for Canadians versus Montreal Jews was 1.43, and 1.46 between Israeli and Montreal Jews; in women, these ratios were 1.87 and 2.90, respectively. CONCLUSIONS: These findings suggest that the mortality pattern characteristic of Israeli Jews is not a universal Jewish phenomenon and may be affected by modifiable environmental factors. Similar studies conducted in other Jewish communities would aid in confirming these observations.

Adult↗

PubMed1995

Trends in blood pressure levels over time in middle-aged and elderly Jerusalem residents.

Change in blood pressure levels over time was investigated in Jerusalem, in two cross-sectional surveys in 1970 and in 1986 among residents of a neighbourhood aged 50 years and more. The study population comprised 1397 individuals in 1970 and 1858 in the 1986. Age-adjusted mean systolic and diastolic blood pressure levels were lower in 1986 than in 1970 by 6.9 mmHg and 4.7 mmHg, respectively. The prevalence of blood pressure levels above 160 and/or 95 mmHg in 1986 was lower by 50% and there was a twofold increase in current treatment for hypertension. The reduction in blood pressure in both sexes remained evident upon control for confounding effects of age, ethnic group, education, body mass index and reported treatment for hypertension. The proportion of people who had blood pressure levels below 140/90 and did not report being under treatment, increased. The possibility of methodological problems inherent in this type of study were considered. More effective antihypertensive treatment in 1986 can explain only part of the reduction. The decrease in levels of blood pressure as revealed by this study may reflect a real reduction in the population that could explain part of the striking decline in cardiovascular mortality in Israel.

Aged↗

PubMed1995

Association between beta-carotene and acute myocardial infarction depends on polyunsaturated fatty acid status. The EURAMIC Study. European Study on Antioxidants, Myocardial Infarction, and Cancer of the Breast.

Because antioxidants may play a role in the prevention of coronary heart disease by inhibiting the peroxidation of polyunsaturated fatty acids (PUFAs), the combined association of diet-derived antioxidants and PUFAs with acute myocardial infarction (MI) was investigated. This multicenter case-control study included 674 patients and 725 control subjects in eight European countries and Israel. Fatty acid composition and alpha-tocopherol and beta-carotene levels were determined in adipose tissue; selenium level was determined in toenails. For alpha-tocopherol no association with MI was observed at any PUFA level. The overall multivariate odds ratio (OR) for low (10th percentile) versus high (90th percentile) beta-carotene was 1.98 (95% confidence interval [CI], 1.39 to 2.82). The strength of this inverse association with MI was dependent on PUFA levels (in tertiles): for low PUFA, the OR for low versus high beta-carotene was 1.79 (95% CI, 0.98 to 3.25), for medium PUFA the OR was 1.76 (95% CI, 1.00 to 3.11), and for high PUFA 3.47 (95% CI, 1.93 to 6.24). For selenium increased risk was observed only at the lowest PUFA tertile (OR, 2.49; 95% CI, 1.22 to 5.09). This interaction between selenium and PUFAs was not significant and may at least partly be explained by a higher proportion of smokers at the low PUFA level. These findings support the hypothesis that beta-carotene plays a role in the protection of PUFAs against oxidation and subsequently in the protection against MI. No evidence was found that alpha-tocopherol or selenium may protect against MI at any level of PUFA intake.

Adipose Tissue↗