心电图QRS波持续时间和左室大小的横断面相关性:Framingham心脏研究

Objectives: The goal of this study was to assess the relations of electrocardiographic QRS duration to left ventricular(LV)measurements in individuals without heart failure(HF) or prior myocardial infarction(MI). Background: Increased electrocardiographic QRS duration(< 120 ms) is a marker of ventricular dyssynchrony. Methods: We evaluated the relations of maximal electrocardiographic QRS duration to echocardiographic LV dimensions in 4,534 Framingham Heart study participants(mean age 54 years, 57% women) without prior HF or MI. QRS duration was analyzed as a continuous variable and as categories(< 100, 100 to 119, and< 120 ms). Results: In linear regression models, LV mass, end- diastolic dimension, and septal and posterior wall thicknesses were positively related to log- QRS duration, whereas fractional shortening(FS) was inversely related(p< 0.001). There was a significant trend for increasing LV mass and dimensions, and decreasing FS across categories of QRS duration(p< 0.001). Left bundle branch block was associated with higher LV mass and lower FS compared with a normal QRS duration(p< 0.001). Conclusions: In our community- based sample of individuals free of HF and MI, increasing electrocardiographic QRS duration was positively related to LV mass and dimensions, and inversely associated with LV FS. Additional investigations are warranted to elucidate the mechanisms underlying the observed associations.

父母心力衰竭与其子女心力衰竭风险的关联性

Background: The association between heart failure in parents and the prevalence of left ventricular systolic dysfunction and the risk of heart failure in their offspring has not been investigated in a community-based setting. Methods: We examined the cross-sectional association of heart failure in parents with the prevalence of left ventricular systolic dysfunction, as well as left ventricular mass, internal dimensions, and wall thickness, in 1497 participants of the Framingham Offspring Study(mean age, 57 years; 819 women) who underwent routine echocardiography. We also investigated prospectively whether heart failure in parents increased the risk of heart failure in 2214 offspring(mean age, 44 years; 1150 women). Results: As compared with the 1039 participants whose parents did not have heart failure, the 458 participants in the cross-sectional cohort who had at least one parent with heart failure were more likely to have increased left ventricular mass(17.0 percent vs. 26.9 percent), left ventricular internal dimensions(18.6 percent vs. 23.4 percent), and left ventricular systolic dysfunction(3.1 percent vs. 5.7 percent); the multivariable-adjusted odds ratios were 1.35(95 percent confidence interval, 0.99 to 1.84), 1.29(95 percent confidence interval, 0.96 to 1.72), and 2.37(95 percent confidence interval, 1.22 to 4.61), respectively. In the longitudinal cohort, heart failure developed in 90 offspring during follow-up(mean length of follow-up, 20 years). The age-and sex-adjusted 10-year incidence rates of heart failure were 2.72 percent among offspring with a parent with heart failure, as compared with 1.62 percent among those without a parent with heart failure. This increase in risk persisted after multivariable adjustment(hazard ratio, 1.70; 95 percent confidence interval, 1.11 to 2.60). Conclusions: Heart failure in parents is associated with an increased prevalence of left ventricular systolic dysfunction cross-sectionally and an elevated risk of heart failure longitudinally. Our data emphasize the contribution of familial factors to the heart-failure burden in the community.

冠心病危险因素水平临界及升高的相对意义

Background: Clinical trials indicate that a sizable proportion of adults have multiple borderline coronary risk factors and may benefit from treatment. Objective: To estimate the relative and absolute contributions of borderline and elevated risk factors to the population burden of coronary heart disease(CHD) events. Design: A prospective cohort study and a national cross- sectional survey. Setting: The Framingham Study and the Third National Health and Nutrition Examination Survey(NHANES III). Participants: White non- Hispanic persons in the Framingham Study and in NHANES III who were between 35 to 74 years of age and had no CHD. Measurements: Occurrence of first CHD events according to 5 major CHD risk factors: blood pressure, low- density lipoprotein and high- density lipoprotein cholesterol levels, glucose intolerance, and smoking. Three categories- optimal, borderline, and elevated- were defined for each risk factor per national guidelines. Sex- specific 10- year CHD event rates from the Framingham Study were applied to numbers of at- risk individuals estimated from NHANES III and the 2000 U.S. Census. Results: Twenty- six percent of men and 41% of women had at least 1 borderline risk factor in NHANES III. According to estimates, more than 90% of CHD events will occur in individuals with at least 1 elevated risk factor, and approximately 8% will occur in people with only borderline levels of multiple risk factors. Absolute 10- year CHD risk exceeded 10% in men older than age 45 years who had 1 elevated risk factor and 4 or more borderline risk factors and in those who had at least 2 elevated risk factors. In women, absolute CHD risk exceeded 10% only in those older than age 55 years who had at least 3 elevated risk factors. Limitations: The generalizability of the findings to persons of other ethnic backgrounds is unknown. Conclusions: Borderline CHD risk factors alone account for a small proportion of CHD events.

炎症、新的危险因素与瓣膜钙化间的关系

Investigators have suggested that inflammation may play a role in the pathogenesis of valve calcium. Participants in the Framingham Heart Study’s offspring cohort had systemic levels of C-reactive protein, intercellular adhesion molecule-1, interleukin-6, and monocyte chemoattractant protein-1 measured at examination cycle 7. Mitral annular calcium, aortic annular calcium, aortic sclerosis, and aortic stenosis were assessed by echocardiography at examination cycle 6. Logistic regression was used to examine the odds of valvular calcium per 1 unit increase in inflammation(ISUM), a summary statistic of all normalized deviates of the individual markers. Two thousand six hundred eighty-three participants(mean age 61±10 years; 52%women) were analyzed: 8.2%(n=216) had ≥1 calcified valve or annulus; 89 had mitral annular calcium, 78 had aortic annular calcium, 135 had aortic sclerosis, and 33 had aortic stenosis. Participants with valvular calcium were older and were more likely to have hypertension and diabetes mellitus. Participants with valve calcium had higher median levels of all markers. For each log unit increase in ISUM, after adjustment for age and gender, there was an associated 1.1-fold increased odds of ≥1 calcified valve(p=0.02); the odds ratios were no longer significant after adjustment for cardiovascular disease risk factors(odds ratio 1.0, 95%confidence interval 0.9 to 1.1). Similar results were obtained for the individual markers and the odds of ≥1 calcified valve. In conclusion, inflammatory markers were elevated in patients with valvular calcium. Our findings suggest that much of the observed association between systemic inflammatory markers and valvular calcium may be due to shared risk factors.

肥胖与新发房颤危险之间的关系

Context: Obesity is associated with atrial enlargement and ventricular diastol ic dysfunction, both known predictors of atrial fibrillation(AF). However, it is unclear whether obesity is a risk factor for AF. Objective: To examine the asso ciation between body mass index(BMI) and the risk of developing AF. Design, Sett ing, and Participants: Prospective, communitybased observational cohort in Fra mingham, Mass. We studied 5282 participants(mean age, 57[SD, 13] years; 2898 wom en[55%]) without baseline AF(electrocardiographic AF or arterial flutter). Body mass index(calculated as weight in kilograms divided by square of height in met ers) was evaluated as both a continuous and a categorical variable(normal define d as < 25.0; overweight, 25.0 to < 30.0; and obese, ≥30.0). In addition to adju sting for clinical confounders by multivariable techniques, we also examined mod els including echocardiographic left atrial diameter to examine whether the infl uence of obesity was mediated by changes in left atrial dimensions. Main Outcome Measure: Association between BMI or BMI category and risk of developing newon set AF. Results: During a mean followup of 13.7 years, 526 participants(234 wo men) developed AF. Age adjusted incidence rates for AF increased across the 3 BM I categories in men(9.7, 10.7, and 14.3 per 1000 personyears) and women(5.1, 8 .6, and 9.9 per 1000 personyears). In multivariable models adjusted for cardio vascular risk factors and interim myocardial infarction or heart failure, a 4%i ncrease in AF risk per 1-unit increase in BMI was observed in men(95%confidenc e interval[CI], 1%-7%; P=.02) and in women(95%CI, 1%-7%; P=.009). Adjuste d hazard ratios for AF associated with obesity were 1.52(95%CI, 1.09-2.13; P=. 02) and 1.46(95%CI, 1.03-2.07; P=.03) for men and women, respectively, compare d with individuals with normal BMI. After adjustment for echocardiographic left atrial diameter in addition to clinical risk factors, BMI was no longer associat ed with AF risk(adjusted hazard ratios per 1-unit increase in BMI, 1.00[95%CI, 0.97-1.04], P=.84 in men; 0.99 [95%CI, 0.96-1.02], P=.56 in women). Conclusi ons: Obesity is an important, potentially modifiable risk factor for AF. The exc ess risk of AF associated with obesity appears to be mediated by left atrial dil atation. These prospective data raise the possibility that interventions to prom ote normal weight may reduce the population burden of AF.

内源性性激素与男性心血管疾病发病率

背景:有资料显示内源性性激素[睾酮、硫酸脱氢表雄酮(DHEA-S)和雌二醇]可影响心血管疾病(CVD)危险因素以及血管功能。然而,关于性激素与男性CVD发病率之间相关性的前瞻性研究结果不一致。目的:检测循环血性激素水平与男性CVD风险的关系。

各年龄段成年人的高血压：当前社区人群的预后和控制

背景：对于80岁以上的人群，目前有关高血压的治疗和控制率以及高血压相关危险性的数据很少。目的：明确老年高血压患者各级别血压的患病率、高血压的治疗率和控制率以及心血管危险因素。设计、地点及参试者：社区队列研究，数据收集于20世纪90年代进入Framinghanl心脏研究的全部检查。根据年龄将入选者集中分层：60岁以下、60～79岁和〉t80岁。共5296例入选者，检查14458人次，其中高血压7135人次（治疗4919例）。主要观测指标：比较各年龄段人群高血压的患病率、治疗率和控制率。6年随访期间发生心血管疾病的危险性，采用Cox比例风险回归的多变量校正风险比（hazardratios，HRs）和95％可信区间（confidenceintervals，CIs）评估。结果：高血压的患病率和药物治疗率随着年龄增加而升高，但是在老年女性控制率（收缩压〈140mmHg，舒张压〈90mmHg）显著降低。〈60岁、60～79岁和t〉80岁组男性的控制率分别为38％、36％和38％（P=0．30）；女性的控制率分别为38％、28％和23％（P〈0．001）。随着年龄增加，与血压分级升高相关的心血管疾病的相对危险性没有下降，而绝对危险性显著升高。在〉t80岁的参试者，正常血压组（对照组）主要心血管事件的发生率为9．5％，高血压前期、1级高血压以及2级或治疗的高血压组的发生率分别为19．8％（HR，1．9；95％CI，0．9～3．9）、20．3％（HR，1．8；95％CI，0．8～3．7）和24．7％（HR，2．4；95％CI，1．2～4．6）。结论：相对于目前的国家指南，在社区人群血压的控制率较低，特别是在老年女性高血压患者。短期心血管疾病危险性很高表明，对于老年高血压患者应加大安全有效降低危险性的力度。

糖尿病心血管并发症的趋势

Context: Despite reductions in cardiovascular disease (CVD) mortality over the past few decades, it is unclear whether adults with and without diabetes have e xperienced similar declines in CVD risk. Objective: To determine whether adults with and without diabetes experienced similar declines in incident CVD in 1950- 1995. Design, Setting, and Participants: Participants aged 4564 years from the F ramingham Heart Study original and offspring cohorts who attended examinations i n 19501966 ("earlier"time period; 4118 participants, 113 with diabetes) and 1977-1995 ("later"time period; 4063 participants, 317 with diabetes). Incid ence rates of CVD among those with and without diabetes were compared between th e earlier and later periods. Main Outcome Measures: Myocardial infarction, coron ary heart disease death, and stroke. Results: Among participants with diabetes, the age-and sex-adjusted CVD incidence rate was 286.4 per 10000 person-years in the earlier period and 146.9 per 10000 in the later period, a 49.3%(95%conf idence interval [Cl], 16.7%-69.4%) decline. Among participants without diabet es, the age-and sex-adjusted incidence rate was 84.6 per 10000 person-years i n the earlier period and 54.3 per 10000 person-yearsin the later period, a 35.4 %(95%Cl, 25.3%-45.4%) decline. Hazard ratios for diabetes as a predictor of incident CVD were not different in the earlier vs later periods. Conclusions: W e report a 50%reduction in the rate of incident CVD events among adults with di abetes, although the absolute risk of CVD is 2-fold greater than among persons without diabetes. Adults with and without diabetes have benefited similarly duri ng the decline in CVD rates over the last several decades. More aggressive treat ment of CVD risk factors and further research on diabetes-specific factors cont ributing to CVD risk are needed to further reduce the high absolute risk of CVD still experienced by persons with diabetes.