Biomedical subjects

M G Larson

Publications and source records attributed to M G Larson.

At least 73 records · Page 4Linked to original sources

PubMed1996

Absence of association or genetic linkage between the angiotensin-converting-enzyme gene and left ventricular mass.

BACKGROUND: Homozygous carries of the D allele of the angiotensin-converting-enzyme (ACE) gene have been reported to be at increased risk for various cardiovascular disorders, including left ventricular hypertrophy. We investigated the potential role of the ACE gene in influencing left ventricular mass. METHODS: Quantitative echocardiographic data and DNA samples were available for 2439 subjects from the Framingham Heart Study. ACE genotypes were determined by an assay based on the polymerase chain reaction. (The D allele of the ACE gene contains a deletion, whereas the I [insertion] allele does not.) Left ventricular mass and the prevalence of left ventricular hypertrophy, adjusted for clinical covariates, were analyzed according to genotype. Genetic linkage between the ACE locus and left ventricular mass was evaluated by quantitative analysis of pairs of siblings. RESULTS: The ACE genotype was associated neither with left ventricular mass nor with the prevalence of left ventricular hypertrophy. Mean (+/-SE) left ventricular mass (adjusted for sex) among subjects carrying the DD, DI, and II genotypes was 165+/-1.6, 165+/-1.3, and 166+/-2.0 g, respectively (P=0.90). The prevalence of left ventricular hypertrophy among the three genotype groups was 15.6 percent, 13.6 percent, and 15.6 percent, respectively (P=0.36), and the adjusted relative risk of left ventricular hypertrophy associated with the DD genotype was 1.10 (95 percent confidence interval, 0.86 to 1.19). Linkage analysis in 759 pairs of siblings using both the ACE D/I marker and a microsatellite polymorphism at the neighboring locus for the human growth hormone gene failed to support any role of ACE in influencing left ventricular mass. CONCLUSIONS: The ACE genotype showed no association with echocardiographically determined left ventricular mass, nor did it confer an increased risk of left ventricular hypertrophy. We found no appreciable role of the ACE gene in influencing left ventricular mass.

Adult↗

PubMed1996

Impaired heart rate response to graded exercise. Prognostic implications of chronotropic incompetence in the Framingham Heart Study.

BACKGROUND: Previous reports have suggested that an attenuated exercise heart rate response may be associated with coronary heart disease risk and with mortality. These observations may parallel the association between reduced heart rate variability during normal activities and adverse outcome. This investigation was designed to look at the prognostic implications of exercise heart rate response in a population-based sample. METHODS AND RESULTS: In this prospective cohort investigation, 1575 male participants (mean age, 43 years) in the Framingham Offspring Study who were free of coronary heart disease, who were not taking beta-blockers, and who underwent submaximal treadmill exercise testing (Bruce protocol) were studied. Heart rate response was assessed in three ways: (1) failure to achieve 85% of the age-predicted maximum heart rate, which has been the traditional definition of chronotropic incompetence; (2) the actual increase in heart rate from rest to peak exercise; and (3) the ratio of heart rate to metabolic reserve used by stage 2 of exercise ("chronotropic response index"). Proportional hazards analyses were used to evaluate the associations of heart rate responses with all-cause mortality and with coronary heart disease incidence during 7.7 years of follow-up. Failure to achieve target heart rate occurred in 327 (21%) subjects. During follow-up there were 55 deaths (14 caused by coronary heart disease) and 95 cases of incident coronary heart disease. Failure to achieve target heart rate, a smaller increase in heart rate with exercise, and the chronotropic response index were predictive of total mortality and incident coronary heart disease (P <.01). Failure to achieve target heart rate remained predictive of incident coronary heart disease even after adjusting for age, ST-segment response, physical activity, and traditional coronary disease risk factors (adjusted hazard ratio, 1.75; 95% confidence interval, 1.11 to 2.74; P=.02). After adjusting for the same factors, the increase in exercise heart rate remained inversely predictive of total mortality (P=.04) and coronary heart disease incidence (P=.0003). The chronotropic response index also was predictive of total mortality (P=.05) and incident coronary heart disease (P=.001) after adjusting for age and other risk factors. CONCLUSIONS: An attenuated heart rate response to exercise, a manifestation of chronotropic incompetence, is predictive of increased mortality and coronary heart disease incidence.

Adult↗

PubMed1996

Doppler diastolic filling indexes in relation to disease states.

This study compares mean Doppler-derived diastolic filling indexes in a variety of disease states in a large, population-based sample. Pulse-wave Doppler was used to examine 880 eligible participants of the Framingham Heart Study. Peak velocity of early flow and late flow, ratio of early to late peak velocities, atrial filling fraction, and early filling wave acceleration and deceleration times were obtained. Multiple linear regression analyses were performed comparing mean values for individuals with hypertension, diabetes, coronary disease, cardiovascular disease, and pulmonary disease. Hypertension was associated with a greater peak velocity late flow (0.027 m/sec; 95% confidence interval, 0.006, 0.047; p = 0.011), and diabetes was associated with a larger mean deceleration time (0.12 sec, confidence interval, 0.002, 0.021; p = 0.016). In multivariate analyses, hypertension continued to show a strong association with altered Doppler diastolic filling patterns, p value 0.009, whereas in diabetes, the multivariate p value was 0.28.

Adult↗

PubMed1996

Apolipoprotein E alleles and risk of coronary disease. A meta-analysis.

A meta-analysis was undertaken to assess the impact of apolipoprotein E (apo E) alleles (epsilon 2, epsilon 3, and epsilon 4) on coronary disease in 14 published observational studies (9 clinical coronary disease and 5 coronary angiography). In comparison with epsilon 3, the epsilon 4 allele was associated with greater odds for coronary heart disease, and summary estimates of the odds ratios (ORs) and (95% confidence intervals) for both sexes combined were OR = 0.98 (0.85-1.14) for epsilon 2 and OR = 1.26 (1.13-1.41) for epsilon 4. Separate analyses for men and women showed similar associations. In angiographic studies the relative odds for significant coronary artery disease among both sexes combined was OR = 0.76 (0.55-1.05) for epsilon 2 and OR = 1.11 (0.88-1.40) for epsilon 4. The overall impression is that epsilon 4 is associated with clinical and coronary disease and that results are similar in men and women.

Adolescent↗

PubMed1995

Assessment of cardiovascular risk factors in the elderly: the Framingham Heart Study.

In elderly Framingham men and women, systolic blood pressure and cigarette smoking status, as well as a subject's age and sex, strongly influenced the risk of developing cardiovascular disease during ten years of follow-up. Multivariable proportional hazards models were used to assess the roles of several primary risk factors and to examine their secondary effects. The first three factors were noted in both sexes, separately and combined, but the risk function for blood pressure was steeper in men than in women (hazard ratio, HR, 1.53 per 20 mmHg, 95 per cent confidence interval, CI, 1.33 to 1.75 in men; HR = 1.19, 95 per cent CI 1.07 to 1.33 in women). Systolic pressure measured ten years earlier also contributed to CVD risk (HR = 1.16 per 20 mmHg, 95 per cent CI 1.04 to 1.30). even after accounting for current level. Smoking was associated with a 64 per cent elevation in risk, male sex with a 51 per cent increase, and each 5 years increment in age with a 22 per cent increase. Body mass index measured 10 years ago had a modest association, but current body mass index did not. Among diabetic subjects, total serum cholesterol had an asymmetrical U-shaped risk function, the risk increasing to either side of sex-specific median values; diabetes per se, however, was not significant in the final model. In non-diabetic subjects, there was little change in CVD risk up to the median cholesterol values and a modest increase thereafter. None of the risk functions was age dependent.

Adult↗

PubMed1995

Determinants of echocardiographic aortic root size. The Framingham Heart Study.

BACKGROUND: Previous studies that evaluated the determinants of aortic root size have not yielded uniform results. We examined the relations of age, height, weight, body surface area, sex, and blood pressure to echocardiographically determined aortic root size in a population-based cohort. METHODS AND RESULTS: The study sample consisted of 1849 men and 2152 women in the Framingham Heart Study and Framingham Offspring Study who were free of clinically apparent cardiac disease when echocardiography was performed. Aortic root measurements were made by M-mode echocardiography using a leading-edge-to-leading-edge technique. The relations of age, height, weight, body surface area, and blood pressure variables (contemporary and those obtained 8 years before) to aortic root dimension were examined by use of sex-specific correlations and linear regression analyses. Age, height, weight, and sex emerged as the principal determinants of aortic root dimensions in adults (cumulative R2 = .2085 in men and .2327 in women). The additional effect of contemporary or previous blood pressure measures was small and revealed direct associations of aortic root dimension with mean arterial and diastolic blood pressures and inverse associations with pulse and systolic blood pressures. Previous blood pressure measurements did not contribute significantly to prediction of aortic root size once contemporary blood pressure variable entered the models. Results of regression analyses using a sex-pooled data set showed that on average, the aortic root measurement in women was 2.4 mm smaller than that of men of comparable age, height, and weight. Logistic regression was used to assess the likelihood of aortic root enlargement according to blood pressure levels. After adjustment for age, height, and weight, the odds ratio of aortic dilation for a 1-SD increment in systolic pressure was 0.70 (95% CI, 0.52 to 0.95) in men and 0.79 (95% CI, 0.60 to 1.04) in women; the odds ratio for a 1-SD increment in diastolic pressure was 1.22 (95% CI, 0.91 to 1.63) in men and 1.33 (95% CI, 1.01 to 1.73) in women. CONCLUSIONS: Age, height, weight, and sex emerged as the principal determinants of aortic root dimensions. The additional influences of blood pressure measurements were small; direct associations of aortic root dimensions with mean arterial and diastolic blood pressures and inverse associations with pulse and systolic blood pressures were observed. Additional prospective studies are needed to confirm these observations and to assess the impact of aortic root dimensions on the incidence of hypertension.

Adult↗

PubMed1995

Gender-specific reference M-mode values in adults: population-derived values with consideration of the impact of height.

OBJECTIVES: The purpose of this investigation was to derive population-based reference values for M-mode echocardiographic dimensions that can be applied in epidemiologic studies, clinical trials and clinical practice and to determine optimal methods for adjusting these dimensions for body size. BACKGROUND: M-mode echocardiography remains an important modality for studying cardiovascular disease; this is especially true with regard to detecting target organ damage in systemic hypertension. Most previously published reference values were derived from hospital-based series or relatively small samples and were not gender specific. METHODS: Using a sample of 288 men and 524 women who were between 20 and 45 years of age and who were free of cardiovascular disease, reference values were derived for end-diastolic and end-systolic left ventricular internal dimensions, left ventricular wall thickness and left atrial dimension. The relations between these dimensions and height, a measure of body size relatively independent of obesity, were investigated using various regression models. RESULTS: Nomograms for mean and 95th percentile values in men and women were constructed on the basis of linear regression models relating echocardiographic dimensions to height. Adjustment for body surface area greatly attenuated associations between obesity and cardiac dimensions in a separate healthy but less restricted sample of 411 men and 503 women. CONCLUSIONS: Gender-specific M-mode reference values and nomograms, with mean and 95th percentile values for echocardiographic dimensions as a function of height, are reported. The use of body surface area as means of body size adjustment is called into question.

Adult↗

PubMed1995

Unexplained gradual-onset Q wave patterns. A case series from the Framingham Study.

Original cohort members of the Framingham Study were studied to determine prognosis associated with unexplained (gradual-onset) Q wave patterns detected on routine electrocardiograms (ECGs). Biennial ECGs were obtained on subjects beginning in 1948. The index ECG was read independently and then serially in relation to all previous tracings for evidence of myocardial infarction. Proportional hazards modeling was used to assess the risk for outcomes in those with unexplained (gradual-onset) Q wave patterns compared with subjects with unrecognized myocardial infarcts (abrupt-onset Q waves) and compared with referent subjects. Unexplained Q wave patterns developed in 53 men and 39 women. Subjects with unexplained Q wave patterns had less than 40% of the risk for myocardial infarction or coronary death as compared with those with unrecognized myocardial infarction after adjusting for risk factors (hazard ratio, 0.38; 95% confidence interval, 0.19, 0.78; P = .008) and a trend toward a lower risk for overall mortality (adjusted hazard ratio, 0.73; 95% confidence interval, 0.46, 1.16; P = .18). Risks for myocardial infarction or coronary death and overall mortality were similar in subjects with unexplained Q wave patterns and referent subjects in the fully adjusted models. Detection of prominent Q waves on an ECG requires comparison with prior tracings to differentiate the unexplained Q wave pattern from the unrecognized infarct, conditions that have significantly different prognostic implications.

Aged↗

PubMed1995

Influence of blood pressure on left atrial size. The Framingham Heart Study.

Increased left atrial size has been identified as a precursor of atrial fibrillation and of stroke once atrial fibrillation is manifest. Conflicting data exist regarding the effect of high blood pressure on left atrial size. Our objective was to evaluate the association of contemporary and long-term measures of blood pressure with echocardiographically determined left atrial size in a large, population-based cohort. The study sample consisted of 1849 male and 2152 female participants of the Framingham Heart Study and Framingham Offspring Study. All analyses were sex specific. In correlation analyses, systolic and pulse pressures were identified as statistically significant determinants of left atrial size after adjustment for age and body mass index, although the magnitudes of these relations were very modest (partial r < or = .10). Multivariable linear regression models showed the relative contributions of the pressure variables to the prediction of left atrial size to be substantially less than those of age and, in particular, body mass index. Furthermore, inclusion of left ventricular mass in these multivariable models eliminated or attenuated the associations of the pressure variables with left atrial size. In logistic analyses, increasing levels of the pressure variables were significantly predictive of left atrial enlargement. Subjects with 8-year average systolic pressure of 140 mm Hg or higher were twice as likely to have left atrial enlargement as those with values of 110 mm Hg or lower. Overall, in this population-based study sample, increased levels of systolic and pulse pressures (but not diastolic or mean arterial pressures) were significantly associated with increased left atrial size.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1995

Objectively measuring physical ability in elderly persons: the Physical Capacity Evaluation.

The Physical Capacity Evaluation, a performance measure of functional capabilities comprised of 13 tasks simulating those used in activities of daily living, was tested on 289 community-dwelling elderly people and compared against a widely used self-report measure of function, the Health Assessment Questionnaire. Factor analysis identified one dominant component in each instrument. Internal consistency reliability (Cronbach's alpha) was .90 for both instruments. Global disability (Health Assessment Questionnaire) and function (Physical Capacity Evaluation) scores were correlated -.74. One-week retest reliabilities on 58 subjects were .94 for the Physical Capacity Evaluation and .95 for the Health Assessment Questionnaire. The Physical Capacity Evaluation is a valid and reliable measure of physical performance for use with elderly people.

Activities of Daily Living↗

PubMed1995

Prognostic factors in systemic necrotizing vasculitis of the polyarteritis nodosa group--a review of 45 cases.

OBJECTIVE: To evaluate the prognostic importance for mortality of age, fever, hypertension, and involvement of renal, cardiac, neural, pulmonary, gastrointestinal and cutaneous systems as well as elevated transaminases, thrombocytosis, leukocytosis, anemia, smoking status, comorbid diseases and disease severity, in 45 patients with systemic necrotizing vasculitis (SNV) identified by histological, radiological, and clinical criteria. METHODS: Kaplan-Meier nonparametric survival functions and Cox proportional hazards regression models were used. RESULTS: Twenty-four deaths were observed during the 5 year mean followup period. Five year survival was 58%. Comorbidity and severity of involvement were not predictive of mortality. Multivariable survival analysis showed that cardiac or renal involvement was associated with a relative risk of dying of 2.91 (95% CI: 1.25, 6.77). Elevated serum transaminase demonstrated a trend to having a protective effect [relative risk of 0.14 (95% CI: 0.02, 1.07)]. No other variable was an independent predictor of fatality. No cohort effect could be documented following the introduction of cytotoxic drugs in the treatment of SNV. CONCLUSION: SNV remains associated with a high mortality due largely to renal or cardiac involvement.

Adult↗

PubMed1994

Apolipoprotein E alleles, dyslipidemia, and coronary heart disease. The Framingham Offspring Study.

OBJECTIVE: To describe the association between apolipoprotein E alleles (epsilon 2, epsilon 3, and epsilon 4), dyslipidemias, and coronary heart disease (CHD). DESIGN: Cross-sectional prevalence study. SETTING AND PARTICIPANTS: Community-based sample of men (n = 1034) and women (n = 916) aged 40 to 77 years who are participating in a long-term study of cardiovascular disease. Study participants underwent fasting lipid measurements, coronary risk factor determinations, and a comprehensive evaluation for the presence of current or previous CHD. RESULTS: Compared with the epsilon 3 allele, the epsilon 4 allele was associated with elevated low-density lipoprotein cholesterol values (> or = 4.14 mmol/L [160 mg/dL]) in women, the epsilon 2 and epsilon 4 alleles were associated with moderately elevated triglyceride values (> or = 2.82 mmol/L [250 mg/dL]) in men, and the epsilon 2 allele was associated with severely elevated triglyceride values (> or = 5.64 mmol/L [500 mg/dL]) in men. The apolipoprotein E alleles were not associated with hypertension, obesity, smoking, or diabetes, but the epsilon 4 allele frequency was reduced in women after 60 years of age. The age-adjusted prevalence of CHD was associated with the epsilon 4 allele in both men (relative odds = 1.53, P = .04) and women (relative odds = 1.99, P = .05). In analyses for women and for both sexes combined, this relation persisted after adjustment by hypertension, smoking, obesity, diabetes, high-density lipoprotein cholesterol, and low-density lipoprotein cholesterol. CONCLUSIONS: Apolipoprotein E alleles are important genetic markers for dyslipidemia and CHD. The estimated CHD odds associated with the epsilon 4 allele appears to be greater than that for any other known genetic lipid abnormality, and the association of the epsilon 4 allele with CHD remains significant in women and both sexes combined after adjustment by traditional coronary risk factors and lipids.

Adult↗

PubMed1994

The long-term clinical outcomes of Lyme disease. A population-based retrospective cohort study.

OBJECTIVE: To ascertain the prevalence of and risk factors for long-term sequelae from acute Lyme disease. DESIGN: Population-based, retrospective cohort study. SETTING: A coastal region endemic for Lyme disease. PARTICIPANTS: Patients with a history of Lyme disease who were previously treated with antibiotics were compared with randomly selected controls. MEASUREMENTS: A standardized physical examination, health status measure (Short Form 36), psychometric test battery, and serologic analysis. RESULTS: Compared with the control group (n = 43), the Lyme group (n = 38; mean duration from disease onset to study evaluation, 6.2 years) had more arthralgias (61% compared with 16%; P < 0.0001); distal paresthesias (16% compared with 2%; P = 0.03); concentration difficulties (16% compared with 2%; P = 0.03); and fatigue (26% compared with 9%; P = 0.04), and they had poorer global health status scores (P = 0.04). The Lyme group also had more abnormal joints (P = 0.02) and more verbal memory deficits (P = 0.01) than did the control group. Overall, 13 patients (34%; 95% CI, 19% to 49%) had long-term sequelae from Lyme disease (arthritis or recurrent arthralgias [n = 6], neurocognitive impairment [n = 4], and neuropathy or myelopathy [n = 3]). Compared with controls, patients who had long-term sequelae had higher IgG antibody titers to the spirochete (P = 0.03) and received treatment later (34.5 months compared with 2.7 months; P < 0.0001). CONCLUSIONS: Persons with a history of Lyme disease have more musculoskeletal impairment and a higher prevalence of verbal memory impairment when compared with those without a history of Lyme disease. Our findings suggest that disseminated Lyme disease may be associated with long-term morbidity.

Cohort Studies↗

PubMed1994

A new method for indexing left ventricular mass for differences in body size.

Left ventricular (LV) mass is determined to a large extent by body size. This has created controversy regarding the optimal method of defining normal values in the clinical setting. Previous groups have advocated indexing LV mass for body surface area, lean body mass, or height, which is an obesity-independent measure of body size. This study describes a new approach that involves dividing LV mass by height raised to a noninteger power. In a sample of 387 men and 714 women who were between 20 and 45 years of age and who were free of cardiovascular disease, the height exponent was determined by logarithmic regression models to be 2.12 in men and 1.91 in women; in a pooled analysis, the height exponent was 1.97. This approach reduced male versus female differences in the mean and 95th percentile values for LV mass; mean value differences who reduced from 52% among raw values to 29% among adjusted values. Compared with height or body surface area indexation, it was found to slightly increase the correlation between LV mass and systolic blood pressure. In contrast, body surface area indexation reduced the association between LV mass and obesity. The current method of indexation is independent of obesity, reduces LV mass variability associated with body size and gender, and may therefore be a useful method for defining normal and abnormal values of LV mass in the clinical setting. The findings of this study also suggest that indexation of LV mass for body surface area is inappropriate.

Adult↗

PubMed1994

The associations of levels of serum potassium and magnesium with ventricular premature complexes (the Framingham Heart Study).

There are conflicting data regarding the impact of serum potassium and magnesium levels on susceptibility to ventricular premature complexes (VPCs) in the clinical setting. The associations of serum potassium and magnesium levels with the prevalence of complex or frequent (> 30/hour, multiform or repetitive) VPCs were examined after adjusting for age, sex, smoking, caffeinated coffee consumption, alcohol consumption, and left ventricular mass in Framingham Offspring Study subjects who were free of clinically apparent heart disease. There were 3,327 eligible subjects (mean age 44 years). Complex or frequent VPCs were present in 183 subjects (5.5%). When age-adjusted prevalences of complex or frequent VPCs were compared among quartiles of serum potassium and magnesium using a trend test, lower potassium (p = 0.002) and lower magnesium (p = 0.010) levels were associated with higher prevalence rates of arrhythmia. In logistic regression analyses that included potassium and magnesium simultaneously, potassium (p = 0.0021) and magnesium (p = 0.0311) levels were inversely associated with the occurrence of complex or frequent VPCs after adjustment for age, sex, smoking, coffee and alcohol consumption, diuretic use, and systolic blood pressure. These associations remained significant after accounting for left ventricular mass. A 1 SD decrement in potassium (0.48 mEq/liter) or magnesium (0.16 mEq/liter) level was associated with a 27% (95% confidence interval 6% to 51%) and a 20% (95% confidence interval 3% to 41%) greater odds of complex or frequent VPCs, respectively. Lower levels of serum potassium and magnesium were concurrently associated with higher prevalence rates of ventricular arrhythmias.

Adult↗

PubMed1994

Left ventricular mass and risk of stroke in an elderly cohort. The Framingham Heart Study.

OBJECTIVE: To evaluate the association of echocardiographically determined left ventricular mass (LVM) with incidence of stroke or transient ischemic attack in an elderly cohort. DESIGN: Cohort study with a follow-up period of 8 years. SETTING: Population-based sample. SUBJECTS: Elderly original cohort subjects of the Framingham Heart Study who were free of cerebrovascular disease and atrial fibrillation at the 16th biennial examination and who had adequate echocardiograms. This group consisted of 447 men (mean age, 67.8 years; range, 60 to 90 years) and 783 women (mean age, 69.2 years; range 59 to 90 years). MAIN OUTCOME MEASURES: Age-adjusted 8-year incidence of stroke was examined as a function of baseline quartiles of LVM-to-height ratio. Proportional hazards regression was used in multivariate analyses to assess risk of stroke as a function of LVM-to-height ratio quartile, adjusting for age, sex, systolic blood pressure, hypertension treatment, diabetes, cigarette smoking, and blood lipid levels. RESULTS: Among the 1230 subjects eligible, 89 cerebrovascular disease events (62 strokes and 27 transient ischemic attacks) occurred during follow-up. In men, 8-year age-adjusted incidence of cerebrovascular events was 18.4% in the highest quartile of LVM-to-height ratio and 5.2% in the lowest quartile. Corresponding values in women were 12.2% and 2.9%. The hazard ratio for cerebrovascular events comparing highest to lowest quartile of LVM-to-height ratio was 2.72 (95% confidence interval [CI], 1.39 to 5.36) after adjusting for age, sex, systolic blood pressure, hypertension treatment, diabetes, cigarette smoking, and the ratio of total cholesterol to high-density lipoprotein cholesterol. After adjusting for age, sex, and cardiovascular disease risk factors, the hazard ratio for cerebrovascular events was 1.45 (95% CI, 1.17 to 1.80) for each quartile increment of LVM-to-height ratio. CONCLUSIONS: Echocardiographically determined LVM-to-height ratio offers prognostic information beyond that provided by traditional cerebrovascular disease risk factors. Echocardiography provides information that facilitates identification of individuals at high risk for stroke and transient ischemic attack.

Aged↗

PubMed1994

Echocardiographic predictors of nonrheumatic atrial fibrillation. The Framingham Heart Study.

BACKGROUND: Although structural heart disease is often present in patients with nonrheumatic atrial fibrillation, the echocardiographic precursors of atrial fibrillation have not been reported previously. In this elderly, population-based cohort, our objective was to examine prospectively the echocardiographic predictors of nonrheumatic atrial fibrillation. METHODS AND RESULTS: Subjects in the Framingham Heart Study were routinely evaluated with M-mode echocardiography; 1924 subjects, ranging in age from 59 to 90 years, comprised the population at risk. Cox proportional hazards modeling was used to analyze the association of selected echocardiographic features with atrial fibrillation risk after adjustment for age, sex, hypertension, coronary heart disease, congestive heart failure, diabetes, and valvular heart disease. During a mean follow-up interval of 7.2 years, 154 subjects (8.0%) developed atrial fibrillation. Multivariable stepwise analysis identified left atrial size (hazard ratio [HR] per 5-mm increment, 1.39; 95% confidence interval [CI], 1.14 to 1.68), left ventricular fractional shortening (HR per 5% decrement, 1.34; 95% CI, 1.08 to 1.66), and sum of septal and left ventricular posterior wall thickness (HR per 4-mm increment, 1.28; 95% CI, 1.03 to 1.60) as independent echocardiographic predictors of atrial fibrillation. For each of the echocardiographic predictors, risk increased progressively over successive quartiles. Moreover, risk increased markedly when highest-risk-quartile measurements for these features were present in combination; the cumulative 8-year age-adjusted atrial fibrillation rates were 7.3% and 17.0%, respectively, when one and two or more highest-risk-quartile features were present, compared with 3.7% when none was present. CONCLUSIONS: In this elderly, population-based sample, left atrial enlargement, increased left ventricular wall thickness, and reduced left ventricular fractional shortening were predictive of risk for nonrheumatic atrial fibrillation. These echocardiographic precursors offer prognostic information beyond that provided by traditional clinical atrial fibrillation risk factors.

Adult↗

PubMed1994

Impact of left ventricular structure on the incidence of hypertension. The Framingham Heart Study.

BACKGROUND: Left ventricular hypertrophy is often found very early in the course of hypertension. It is not known whether increased left ventricular mass contributes to the pathogenesis of hypertension. The purpose of this study was to examine the impact of left ventricular mass and other echocardiographically assessed cardiac structural features on the incidence of hypertension. METHODS AND RESULTS: Subjects for this investigation included participants in the Framingham Heart Study and the Framingham Offspring Study who were normotensive at the baseline examination (systolic blood pressure, < 140 mm Hg; diastolic blood pressure, < 90 mm Hg; not receiving antihypertensive medications) and free of coronary heart disease, congestive heart failure, valvular heart disease, hypertrophic cardiomyopathy, diabetes mellitus, and renal insufficiency. The study sample included 1121 men (mean age, 44.4 years) and 1559 women (mean age, 45.6 years). Four years after the baseline examination, 202 men (18.0%) and 257 women (16.5%) were hypertensive (systolic blood pressure, > or = 140 mm Hg; diastolic blood pressure, > or = 90 mm Hg; or use of antihypertensive medications). Baseline echocardiographic left ventricular mass (P = .01) and the sum of septal and posterior left ventricular wall thicknesses (P = .02) were associated with progression to hypertension. After adjusting for sex, baseline age, systolic and diastolic blood pressures, body mass index, alcohol intake, and systolic blood pressure from an examination 8 years earlier, the odds ratio for developing hypertension for a 1-SD increment in left ventricular mass index was 1.20 (95% confidence interval, 1.04 to 1.39), and the odds ratio for a 1-SD increment in left ventricular wall thickness was 1.16 (95% confidence interval, 1.02 to 1.33). CONCLUSIONS: In these normotensive adults, increased left ventricular mass and wall thickness were associated with the development of hypertension. Further studies are warranted to examine the utility of echocardiography in determining the need for antihypertensive therapy and to assess the effect of earlier intervention on the course of progression to hypertension.

Adult↗