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

Summary. Background: 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. Aims: The aim of the study was to quantify the risk reduction of incident myocardial infarction provided by a Mediterranean dietary pattern. Methods: 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. Results: 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). Conclusions: 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. Received: 24 January 2002, Accepted: 13 May 2002     

Role of fibre and fruit in the Mediterranean diet to protect against myocardial infarction: a case-control study in Spain

OBJECTIVE: To assess the association between a first acute myocardial infarction and the consumption of fibre and fruit. DESIGN: Hospital-based case-control study with incident cases. A validated semi-quantitative food frequency questionnaire (136 items) was used to assess food intake. SETTING: Three third-level university hospitals in Pamplona (Spain). SUBJECTS: Cases were subjects aged under 80, newly diagnosed with acute myocardial infarction. Each case patient (n=171) was matched to a control subject of the same gender and age (5 y bands) admitted to the same hospital. RESULTS: An inverse association was apparent for the three upper quintiles of fibre intake. After adjustment for non-dietary and dietary confounders, an inverse linear trend was clearly significant, showing the highest relative reduction of risk (86%) for the fifth quintile (OR=0.14, 95% confidence interval: 0.03-0.67). An inverse association was also apparent for fruit intake, but not for vegetables or legumes. CONCLUSIONS: Our data suggest that a substantial part of the postulated benefits of the Mediterranean diet on coronary risk might be attributed to a high intake of fibre and fruit.     

Dietary folate and the risk of nonfatal myocardial infarction

BACKGROUND: Elevated homocysteine levels have been associated with a higher risk of cardiovascular disease. Because folate intake can reduce homocysteine levels, we investigated the association between dietary folate intake and nonfatal myocardial infarction. METHODS: We conducted a case-control study in three tertiary hospitals of Pamplona, Spain, between 1999 and 2001. Study physicians enrolled 171 patients less than 80 years of age with a first nonfatal myocardial infarction and 171 control patients matched by age, sex, hospital and calendar month. We excluded patients with any prior major cardiovascular disease. Participants were interviewed about medical factors and life-style and completed a food frequency questionnaire previously validated in Spain. We calculated energy-adjusted intakes of folate and estimated relative risks (RRs) of myocardial infarction and 95% confidence intervals (CIs) using conditional logistic regression. Relative risks were adjusted for conventional risk factors. RESULTS: Only 6% of participants were taking vitamin supplements. The main sources of folate were green leafy vegetables, green beans, oranges, peppers and lettuces. The estimated matched RR of myocardial infarction for the top three quartiles of folate intake (, above 340 microg/day) was 0.57 (CI = 0.35-0.94), compared with the lowest quartile of intake. The multivariate adjusted RR was 0.51 (CI = 0.24-1.06). There was no apparent dose effect above this threshold. CONCLUSIONS: Our results in a Mediterranean population with natural plant foods as the main source of folate provide further evidence to support the hypothesis that dietary folate intake may be an independent protective factor for myocardial infarction. The magnitude of the effect, its biological plausibility, and the consistency across studies offer support for a causal association.     

Risk of first non-fatal myocardial infarction negatively associated with olive oil consumption: a case-control study in Spain

BACKGROUND: Olive oil is the main source of dietary lipids in most Mediterranean countries where mortality and incidence rates for coronary heart disease (CHD) are the lowest in Europe. Although international comparisons and mechanistic reasons support the hypothesis that a high olive oil intake may prevent CHD, limited data from studies of individuals are available. METHODS: A hospital-based case-control study was conducted in Pamplona (Spain) recruiting 171 patients (81% males, age <80 years) who suffered their first acute myocardial infarction and 171 age-, gender- and hospital-matched controls (admitted to minor surgery, trauma or urology wards). A validated semi-quantitative food frequency questionnaire (136 items) was used to appraise previous long-term dietary exposures. The same physician conducted the face-to-face interview for each case patient and his/her matched control. Conditional logistic regression modelling was used to take into account potential dietary and non-dietary confounders. RESULTS: The exposure to the upper quintile of energy-adjusted olive oil (median intake: 54 g/day) was associated with a statistically significant 82% relative reduction in the risk of a first myocardial infarction (OR = 0.18; 95% CI : 0.06-0.63) after adjustment for dietary and non-dietary confounders. CONCLUSIONS: Our data suggest that olive oil may reduce the risk of coronary disease. These findings require confirmation in further observational studies and trials.     

Mediterranean diet and all-causes mortality after myocardial infarction: results from the GISSI-Prevenzione trial

OBJECTIVE: To ascertain whether simple dietary advice to increase the consumption of Mediterranean foods, given in a clinical setting, leads to reduced mortality after a myocardial infarction. DESIGN: Data were used from the GISSI-Prevenzione clinical trial, analysed as a cohort study with adjustment for treatment allocation. SETTING: A total of 172 centres in Italy. SUBJECTS: A total of 11323 men and women with myocardial infarction. All subjects received advice to increase their consumption of fish, fruit, raw and cooked vegetables and olive oil. MEASUREMENTS: The intakes of the five foods were assessed at baseline, 6, 18 and 42 months. Associations of food intakes, a combined dietary score, and the risk of death over 6.5 y were estimated adjusting for several non-dietary variables, using pooled logistic regression. RESULTS: Subjects generally improved their diet according to the advice given. All foods were associated with a significant reduction in risk of death. Compared with people in the worst dietary score quarter, the odds ratio for those in the best score quarter was 0.51 (95% CI 0.44-0.59). A good diet had a protective effect in sub-groups defined by age, sex, smoking, randomized treatment and concomitant drug therapy. CONCLUSIONS: Myocardial infarction patients can respond positively to simple dietary advice, and this can be expected to lead to a substantial reduction in the risk of early death. Regardless of any drug treatment prescribed, clinicians should routinely advise patients with myocardial infarction to increase their frequency of consumption of Mediterranean foods.     

A population-based case-referent study of myocardial infarction and occupational exposure to motor exhaust, other combustion products, organic solvents, lead, and dynamite. Stockholm Heart Epidemiology Program (SHEEP) Study Group

This case-referent study investigated the risk of myocardial infarction from occupational exposure to motor exhaust, other combustion products, organic solvents, lead, and dynamite. We identified first-time, nonfatal myocardial infarctions among men and women 45-70 years of age in Stockholm County from 1992 through 1994. We selected referent subjects from the population to match the demographic characteristics of the cases. A lifetime history of occupations was obtained by questionnaire. The response rate was 81% for the cases and 74% for the referents, with 1,335 cases and 1,658 referents included in the study. An occupational hygienist assessed occupational exposures, coding the intensity and probability of exposure for each subject. We adjusted relative risk estimates for tobacco smoking, alcohol drinking, hypertension, diabetes mellitus, overweight, and physical inactivity at leisure time. The relative risk of myocardial infarction was 2.11 (95% confidence interval = 1.23-3.60) among those who were highly exposed and 1.42 (95% confidence interval = 1.05-1.92) among those who were intermediately exposed to combustion products from organic material. We observed an exposure-response pattern, in terms of both maximum exposure intensity and cumulative dose. Exposure to dynamite and organic solvents was possibly associated with an increased risk. The other exposures were not consistently associated with myocardial infarction.     

The relationship between adherence to the Mediterranean diet and the severity and short-term prognosis of acute coronary syndromes (ACS): The Greek Study of ACS (The GREECS)

BACKGROUND: Although adherence to the Mediterranean diet has long been associated with lower incidence of various chronic diseases among apparently healthy individuals, its relationship with the severity and short prognosis (30 d) of patients with cardiovascular disease has rarely been investigated. OBJECTIVE: We sought to evaluate the association between adherence to the Mediterranean diet and the severity and prognosis of acute coronary syndromes. METHODS: From October 2003 to September 2004, a sample of 6 hospitals located in several urban and rural Greek regions was selected, and almost all survivors after an acute coronary syndrome were enrolled into the study (2172 patients were included in the study; 76% were men and 24% women). Adherence to the Mediterranean diet was assessed by a diet score that incorporated the inherent characteristics of this diet. Higher values of the score (range 0-55) were closer to the Mediterranean diet. Biochemical indices of myocardial damage were also considered. RESULTS: Diet score was inversely correlated with entry values of cardiac troponin I (rho = -0.19, P < 0.001), creatine phosphokinase (rho = -0.09, P < 0.001), and creatine phosphokinase-MB (rho = -0.09, P < 0.001). An increment in the diet score was associated with significant decrease in troponin I and creatine phosphokinase-MB levels (P < 0.01) after adjusting for various potential confounders. Moreover, diet score was associated with lower risk of recurrent events (odds ratio = 0.81, 95% confidence interval 0.61-0.98). However, this association became insignificant when the discharge diagnosis of the patients was taken into account. CONCLUSION: Background dietary habits close to the Mediterranean diet seem to be associated with lower severity of coronary heart disease.     

Transient exposure to coffee as a trigger of a first nonfatal myocardial infarction

BACKGROUND: The effects of coffee on myocardial infarction are uncertain. We hypothesize that coffee in the presence of predisposing factors can induce a cascade of events that, through sympathetic nervous activation, can induce the onset of myocardial infarction. METHODS: We recruited 503 incident cases of nonfatal myocardial infarction between 1994 and 1998 in Costa Rica. We used a case-crossover design to calculate relative risks (RRs) and 95% confidence intervals (95% CIs). RESULTS: The RR of myocardial infarction in the hour after coffee intake was 1.49 (95% CI = 1.17-1.89). Occasional coffee drinkers (< or =1 cup/day, n = 103) had a RR of myocardial infarction of 4.14 (2.03-8.42), moderate coffee drinkers (2-3 cups/day, n = 280) had a RR of 1.60 (1.16-2.21), and heavy coffee drinkers (> or =4 cups/d, n = 120) had a RR of 1.06 (0.69-1.63; P = 0.006, test of homogeneity). Patients with 3 or more risk factors (n = 101) had a RR of myocardial infarction of 2.10 (1.30-3.39), whereas patients with fewer than 3 risk factors (n = 396) had a RR of 1.39 (1.04-1.82; P = 0.15, test of homogeneity); and RR was 1.72 (1.30-2.30) among sedentary patients compared with 1.07 (0.66-1.72) among nonsedentary (P = 0.10, test of homogeneity). CONCLUSIONS: The findings indicate that coffee intake may trigger myocardial infarction. The association is particularly strong among people with light/occasional intake of coffee (< or =1 cup/day), with sedentary lifestyle, or with 3 or more risk factors for coronary heart disease.     

Swedish moist snuff and myocardial infarction among men

BACKGROUND: Previous studies have provided inconsistent results on possible increased risk of cardiovascular disease with the use of smokeless tobacco. The aim of this study was to assess whether long-term use of Swedish moist snuff (widely used among Swedish men) increases the risk of acute myocardial infarction. METHODS: This case-control study was conducted in 2 Swedish counties. We identified 1760 men, age 45-70 years, who had a myocardial infarction in 1992-1994. We randomly selected male controls from the study base after stratification for age and hospital catchment area. Information about snuff consumption, smoking history, hypertension, and other factors was obtained by mailed questionnaire and medical examination. The participation rate was 77% among cases and 78% among controls, with tobacco use data available for 1432 cases and 1810 controls. RESULTS: After adjustment for age, hospital catchment area, and smoking, the relative risk of first acute myocardial infarction was 1.1 (95% confidence interval=0.8-1.5) for former snuff users and 1.0 (0.8-1.3) for current snuff users. Analyses limited to either nonfatal or fatal cases did not change the results. Among the controls, the consumption of smokeless tobacco was strongly associated with certain risk factors for myocardial infarction such as smoking, hypertension, and high body mass index. CONCLUSION: The hypothesis that smokeless tobacco increases the risk for myocardial infarction is not supported in the present study.     

Association of fast food consumption with energy intake, diet quality, body mass index and the risk of obesity in a representative Mediterranean population

The aim of the present study was to describe the association of fast food consumption with BMI, energy intake and diet quality in a Mediterranean population. The subjects were Spanish men (n 1491) and women (n 1563) aged 25-74 years who were examined in 1999-2000, in a population-based cross-sectional survey in northeast Spain (Girona). Dietary intake was assessed using a FFQ that included four typical fast food items. Two dietary-quality indices, the Mediterranean diet score and the healthy eating index, were created. Height and weight were measured. Within the population studied, 10.1 % reported eating fast food at least once per month. Dietary energy intake and energy density were directly associated with frequency of fast food consumption. Multivariate logistic regression analysis adjusted for lifestyle and educational level showed an inverse association of frequency of fast food consumption with meeting the dietary reference intake (DRI) for energy (P = 0.001). The consumption of fast food more than once per week increased the risk of overall low diet quality (P < 0.001). BMI was directly associated with fast food consumption expressed in g/d (P = 0.025) and in kJ/d (P = 0.017). The risk of being obese increased with the frequency of fast food consumption (P = 0.046). Fast food consumption was associated with higher energy intakes, poor diet quality and higher BMI. The likelihood of not meeting the DRI for energy, and of being obese, increased with the frequency of fast food consumption.     

Mediterranean diet and cardiovascular diseases in an Israeli population

BACKGROUND: Israel is in the Mediterranean basin, but its population immigrated mostly from Europe, Asia, and Africa. We surveyed the adherence of the Israeli Jewish population to Mediterranean Diet (MD) and its association with cardiovascular disease. METHODS: We studied a random sample of Jewish adults, aged 35+ using a 24-h recall questionnaire. A MD score (scale 0-8) was computed reflecting high ratio of monounsaturated to saturated fat; high intake of alcohol, legumes, cereals, vegetables, and fruits; low intakes of meat and it's products, milk and dairy products. Scoring <5 was defined as Low-MD consuming, while 5+ as High-MD consuming. RESULTS: Five hundred twenty men and 639 women participated in the study, with High-MD consumers constituting 19% and 17% by sex, respectively. The risk for myocardial infarction, coronary bypass, angioplasty, and any cardiovascular disease in men increased by 1.2 (P = 0.04), 1.6 (P = 0.01), 1.4 (P = 0.003), and 1.3 (P = 0.01), respectively, for each MD score decrease. In women, crude odds ratios ranged from 1.4 to 1.9 but were not statistically significant. CONCLUSIONS: The current rate of MD in Israel is fairly low. Given the MD's proven preventive effect and local availability of foods, a reasonably priced MD diet can be devised and recommended widely in our population.     

Dietary intake of alpha-linolenic acid and risk of fatal ischemic heart disease among women

BACKGROUND: Experimental studies in laboratory animals and humans suggest that alpha-linolenic acid (18:3n-3) may reduce the risk of arrhythmia. OBJECTIVE: The objective was to examine the association between dietary intake of alpha-linolenic acid and risk of fatal ischemic heart disease (IHD). DESIGN: This was a prospective cohort study. The intake of alpha-linolenic acid was derived from a 116-item food-frequency questionnaire completed in 1984 by 76283 women without previously diagnosed cancer or cardiovascular disease. RESULTS: During 10 y of follow-up, we documented 232 cases of fatal IHD and 597 cases of nonfatal myocardial infarction. After adjustment for age, standard coronary risk factors, and dietary intake of linoleic acid and other nutrients, a higher intake of alpha-linolenic acid was associated with a lower relative risk (RR) of fatal IHD; the RRs from the lowest to highest quintiles were 1.0, 0.99, 0.90, 0.67, and 0.55 (95% CI: 0.32, 0.94; P for trend = 0.01). For nonfatal myocardial infarction there was only a modest, nonsignificant trend toward a reduced risk when extreme quintiles were compared (RR: 0.85; 95% CI: 0.61, 1.19; P for trend = 0.50). A higher intake of oil and vinegar salad dressing, an important source of alpha-linolenic acid, was associated with reduced risk of fatal IHD when women who consumed this food > or =5-6 times/wk were compared with those who rarely consumed this food (RR: 0.46; 95% CI: 0.27, 0.76; P for trend = 0.001). CONCLUSIONS: This study supports the hypothesis that a higher intake of alpha-linolenic acid is protective against fatal IHD. Higher consumption of foods such as oil-based salad dressing that provide polyunsaturated fats, including alpha-linolenic acid, may reduce the risk of fatal IHD.     

Alcohol and exercise in myocardial infarction and sudden coronary death in men and women

The relation of alcohol consumption and regular leisure time physical activity with nonfatal myocardial infarction and sudden coronary death in men and women of Auckland, New Zealand, was examined in a large population-based case-control analysis. Within each sex, alcohol drinkers had decreased relative risks of both myocardial infarction and sudden coronary death compared with nondrinkers. Similarly, physical activity was associated with decreased relative risks of myocardial infarction and sudden coronary death in both women and men, but only in those subjects who had been exercising for five or more years. After controlling for hypertension, cigarette smoking, and alcohol consumption, 43% (95 confidence interval (CI) = 26-60) of coronary events could be explained by lack of exposure to physical activity. This compares with the per cent of coronary events in the study population attributable to hypertension (22%; 95% CI = 17-27) or cigarette smoking (31%; 95% CI = 25-38). Although the estimation of the attributable risk for a continuous variable is affected by the cut-point used to define exposure, from a public health viewpoint, regular leisure time physical activity may be as important as the above-mentioned major coronary heart disease risk factors.     

Adherence to the Mediterranean diet is associated with total antioxidant capacity in healthy adults: the ATTICA study

BACKGROUND: Greater adherence to the Mediterranean diet has been associated with a lower incidence of cardiovascular disease and cancer. OBJECTIVE: We studied the effect of the Mediterranean diet on total antioxidant capacity (TAC) in 3042 participants who had no clinical evidence of cardiovascular disease. DESIGN: During 2001-2002, a random sample of 1514 men and 1528 women aged 18-89 y from the Attica area of Greece was selected. TAC was measured with an immune-diagnostic assay. Food consumption was evaluated with a validated food-frequency questionnaire, and adherence to the Mediterranean diet was assessed on the basis of a diet score that incorporated the inherent characteristics of this diet. RESULTS: TAC was positively correlated with diet score. The participants in the highest tertile of the diet score had, on average, 11% higher TAC levels than did the participants in the lowest tertile, even after adjustment for relevant confounders (P < 0.01). On the other hand, the participants in the highest tertile of the diet score had, on average, 19% lower oxidized LDL-cholesterol concentrations than did the participants in the lowest tertile (P < 0.01). An additional analysis showed that TAC was positively correlated with the consumption of olive oil (rho = 0.54, P = 0.002) and of fruit and vegetables (rho = 0.34 and rho = 0.31, respectively; P < 0.001 for both), whereas it was inversely associated with the consumption of red meat (rho = -0.35, P = 0.02). CONCLUSION: Greater adherence to the Mediterranean diet is associated with elevated TAC levels and low oxidized LDL-cholesterol concentrations, which may explain the beneficial role of this diet on the cardiovascular system.     

Effect of interaction between adherence to a Mediterranean diet and the methylenetetrahydrofolate reductase 677C-->T mutation on homocysteine concentrations in healthy adults: the ATTICA Study

BACKGROUND: Dietary and genetic factors may influence the effect of raised homocysteine concentrations on coronary artery disease risk. OBJECTIVE: We evaluated the effect of the interaction between adoption of a Mediterranean diet and the methylenetetrahydrofolate reductase gene (MTHFR) 677C-->T mutation on homocysteine concentrations in healthy adults participating in the ATTICA study. DESIGN: We studied demographic, lifestyle, clinical, biochemical, and genetic information from 322 men (x +/- SD age: 46 +/- 13 y) and 252 women (45 +/- 14 y) who had no clinical evidence of cardiovascular or any other chronic disease. We also measured total plasma homocysteine concentrations, the distribution of the MTHFR genotype, and adherence to a Mediterranean diet. RESULTS: The distribution of MTHFR genotypes was as follows: homozygous normal (CC), 41%; heterozygous (CT), 48%; and homozygous mutant (TT), 11%. Homocysteine concentrations were higher in persons with the TT genotype than in those with the CC and CT genotypes (x +/- SD: 15.8 +/- 9 compared with 11.3 +/- 8 and 10.8 +/- 9 micromol/L, respectively; P < 0.001). The Mediterranean diet score was not significantly associated with homocysteine concentrations (P = 0.89). However, after control for potential confounders, the stratified analysis showed that adherence to a Mediterranean diet was associated with reduced homocysteine concentrations in persons with the TT and CT genotypes (beta = -0.21, P = 0.002, and beta = -0.14, P = 0.025, respectively) but not in those with the CC genotype (beta = -0.03, P = 0.38). CONCLUSION: The observed association of an MTHFR 677C-->T gene-diet interaction on homocysteine concentrations may provide a pathophysiologic explanation for how a Mediterranean diet may influence coronary risk in persons with raised homocysteine concentrations.     

The Mediterranean Diet Is Associated with a Reduction in Premature Mortality among Middle-Aged Adults

The available large prospective studies supporting an inverse association between better adherence to the Mediterranean diet and lower mortality have mainly included older adults. It is not clear whether this inverse association is also present among younger individuals at lower mortality risk. Our aim was to assess the association between adherence to the Mediterranean diet and total mortality in middle-aged adults from the Seguimiento Universidad de Navarra (SUN) Project. We followed 15,535 Spanish university graduates for a mean of 6.8 y. Their mean age was 38 ± 12 y, 59.6% were females, and all were initially free of cardiovascular disease, cancer, and diabetes. A validated FFQ was used to assess dietary habits. Adherence to the Mediterranean diet was categorized into 3 groups according to the Mediterranean Diet Score (low, 0-2 points; moderate, 3-5 points; and high, 6-9 points). The outcome variable was total mortality. Cox proportional hazards models were used to estimate HR and 95% CI. We adjusted the estimates for sex, age, years of university education, BMI, smoking, physical activity, television watching, history of depression and baseline hypertension, and hypercholesterolemia. We observed 125 deaths during 105,980 person-years of follow-up. The fully adjusted HR for moderate and high adherence were 0.58 (95% CI: 0.34, 0.99; P = 0.05) and 0.38 (95% CI: 0.21, 0.70; P = 0.002), respectively. For each 2-point increment in the Mediterranean Diet Score, the HR of death was 0.72 (95% CI: 0.58, 0.91; P = 0.006). Among highly educated, middle-aged adults, adherence to the traditional Mediterranean diet was associated with reduced risk of death.     

多普勒超声及Fibroscan评分系统在慢性乙型肝炎肝纤维化诊断中的应用价值

目的:探讨基于多普勒超声及Fibroscan构建的肝纤维化无创评分系统对慢性乙型肝炎患者的肝纤维化诊断价值。方法:选取在医院行超声引导下肝穿刺活检的300例乙型肝炎患者,根据肝穿刺活检结果将其分为肝纤维化组(172例)和非肝纤维化组(128例)。比较两组患者的性别、年龄、病程、彩色多普勒超声检查结果与Fibroscan硬度值(LSM值),将差异有统计学意义的变量纳入多因素Logistic回归分析中确定肝纤维化影响因素。根据逐步Logistic回归分析筛选出影响因素的标准化回归系数β得到相应的评分赋值,构成肝纤维化无创评分系统。绘制受试者工作特征(ROC)曲线,分析该评分系统诊断肝纤维化的诊断效能,确定最佳临界值以及敏感性和特异性。为进一步验证该评分系统对肝纤维化的诊断价值,另选行肝穿刺活检的100例乙型肝炎患者进行评分。结果:肝纤维化组中男性、肝被膜欠光滑、肝实质回声不均匀、肝内光点增粗、肝静脉清晰度较差的占比均明显高于非肝纤维化组,差异有统计学意义(χ²=4.089,χ²=12.105,χ²=7.792,χ²=9.383,χ²=7.053;P<0.05);脾长径、脾厚度、脾脏面积、胆囊壁厚度、肝固有动脉峰值血流速度(HAV_max)、肝固有动脉/门静脉峰值流速的比值(A/P)、肝脏硬度值(LSM)均明显高于非肝纤维化组,门静脉峰值血流速度(PVV_max)、脾静脉峰值血流速度(SVV_max)、肝脏循环指数(HCI)明显低于非肝纤维化组,差异有统计学意义(t=2.296,t=2.228,t=2.364,t=5.970,t=2.864,t=6.083,t=10.268,t=2.925,t=5.749,t=2.209;P<0.05)。多因素Logistic回归分析证实,患者性别、肝被膜光滑程度、肝实质回声、肝内光点增粗、肝静脉清晰度、胆囊壁厚度、HCI、A/P以及LSM值是肝纤维化的影响因素。根据筛选出的影响因素的标准化回归系数β得到对应评分赋值,最终该评分系统的总分为0~12分,其中0~7分为低危,8~9分为中危,10~12分为高危。以患者总评分为自变量、肝纤维化情况为因变量绘制的ROC曲线下面积为0.948(95%CI:0.835~0.989),最佳临界值为10分,此时灵敏度和特异度分别为93.46%和81.05%。100例乙型肝炎患者基于评分系统的诊断结果与肝穿刺结果有高度一致性(Kappa值=0.762)。结论:基于彩色多普勒超声和FibroScan所构建的肝纤维化无创评分系统可为肝纤维化的诊断及抗纤维化提供有力依据。     

A brief assessment of eating habits and weight gain in a Mediterranean cohort

Assessment of eating habits (EH) through closed questions could be an alternative tool to assess diet as a predictor of weight change in epidemiological studies. The aim was to assess the association between baseline EH and the risk of weight gain or becoming overweight/obese in a Spanish dynamic prospective cohort (the Seguimiento Universidad de Navarra Project) of 10?509 participants. The baseline questionnaire included ten short questions with two possible answers: yes or no. We calculated a baseline EH score, categorised in quartiles, positively weighting answers on more fruit, vegetables, fish and fibre and less meat, sweets and pastries, fat, butter, fatty meats and added sugar in drinks. Reducing the consumption of meat or fat and removing fat from meat were significantly associated with lower weight gain. The partial correlation coefficient between EH score and weight change was -?0·033 (P?=?0·001). We observed 1063 cases of incident overweight/obesity among 7217 participants without overweight/obesity at baseline. Trying to eat more fruit, fish or fibre and less meat was inversely significantly associated with incident overweight/obesity. Those participants in the upper quartile of the score were at a 38?% (adjusted OR 0·62; 95?% CI 0·48, 0·81) lower risk of developing overweight/obesity during the follow-up compared with those in the lower quartile. However, the receiver-operating characteristic curves for the model with and without the EH score were materially identical. Despite the apparent significant inverse association, this score had a low predictive value for future weight gain and for incident overweight/obesity in a Mediterranean population, although some EH were independently and positively associated with weight gain.     

The risk of acute myocardial infarction and arterial hypertension in a cohort of male employees of a Siberian Group of Chemical Enterprises exposed to long-term irradiation

During the period from 1998 to 2007, a prospective cohort study of acute myocardial infarction morbidity cases as well as a "case-control" study of arterial hypertension was carried out. The risk of acute myocardial infarction was assessed as well as arterial hypertension; the dose-response relationship and the role of radiation in the mechanism of acute myocardial infarction as well as arterial hypertension development were studied. As a result of this study, a statistically significant increased risk of acute myocardial infarction among the male staff at the Siberian Group of Chemical Enterprises [standardized relative risk = 1.16 (1.04; 1.29)] exposed to external irradiation in comparison with employees unexposed to ionizing radiation was observed. A significant increase in the risk of acute myocardial infarction was observed at external radiation dose accumulation of more than 300 mSv [standardized relative risk = 1.46 (1.09; 1.91)]. The increase in arterial hypertension risk has been established among the analyzed group of employees exposed to long-term irradiation in the absence of the linear dependence of risk, based on cumulative dose of external γ-irradiation [risk due to external radiation dose in the range of 7.3-21.3 mSv = 1.6 (0.96; 2.51) and in the range of external radiation dose 21.4-68.5 mSv = 1.7 (1.04; 2.67) for 68.6-864 mSv = 1.6 (1.01; 2.57)]. This led to the conclusion that radiation can act also as a factor that might potentiate the negative effects of the "traditional" risk factors in the pathogenesis of acute myocardial infarction and hypertension.     

Dietary iron and risk of myocardial infarction in the Rotterdam Study

Free iron has been implicated in lipid peroxidation and ischemic myocardial damage, and it has been suggested that iron is an independent risk factor for myocardial infarction. The authors investigated whether dietary iron is associated with an increased risk of fatal and nonfatal myocardial infarction in the Rotterdam Study, a community-based prospective cohort study of 7,983 elderly subjects in Rotterdam, the Netherlands. The study sample consisted of 4,802 participants who at baseline had no known history of myocardial infarction and for whom dietary data were available. From 1990 to 1996, 124 subjects had a myocardial infarction. No association was observed between total iron intake and risk of myocardial infarction after adjustment for age and sex (relative risk for the highest vs. the lowest tertile of intake = 0.89, 95% confidence interval (CI) 0.55-1.45, p for trend = 0.640). Heme iron intake was positively associated with risk of myocardial infarction (relative risk for the highest vs. the lowest tertile of intake = 1.83, 95% CI 1.16-2.91, p for trend = 0.008) after adjustment for age and sex, and this association persisted after multivariate adjustment (relative risk = 1.86, 95% CI 1.14-3.09, p for trend = 0.010). A distinction between fatal and nonfatal cases of myocardial infarction indicated that the association of heme iron with myocardial infarction was more pronounced in fatal cases. The results suggest that a high dietary heme iron intake is related to an increased risk of myocardial infarction and that it may specifically affect the rate of fatality from myocardial infarction.