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Recent studies demonstrated associations between occlusive vascular disease and hyperhomocysteinemia of both genetic and nutritional origin. In the present study we analyzed plasma samples from the 20th biannual examination of the Framingham Heart Study cohort to determine distribution of plasma homocysteine concentrations with emphasis on relationships to B vitamins and prevalence of carotid artery stenosis. Results showed that homocysteine exhibited strong inverse association with plasma folate and weaker associations with plasma vitamin B-12 and pyridoxal-5'-phosphate (PLP). Homocysteine was also inversely associated with intakes of folate and vitamin B-6, but not vitamin B-12. Prevalence of high homocysteine (> 14 [micro]mol/l) was 29.3% in this cohort, and inadequate plasma concentrations of one or more B vitamins appear to contribute to 67% of the cases of high homocysteine. Prevalence of stenosis [greater than or equal to]25% was 43% in men and 34% in women with an odds ratio of 2.0 for individuals in the highest homocysteine quartile ([greater than or equal to]14.4 [micro]mol/l) compared with those in the lowest quartile ([less than or equal to]9.1 [micro]mol/l), after adjustment for sex, age, high density lipoprotein cholesterol, systolic blood pressure and cigarette smoking ([P.sub.trend] < 0.001). Plasma concentrations of folate and pyridoxal-5'-phosphate and folate intake were inversely associated with extracranial carotid stenosis after adjustment for age, sex and other risk factors. J. Nutr. 126: 1258S-1265S, 1996. INDEXING KEY WORDS: homocysteine, folic acid, pyridoxal phosphate, vitamin B-6, vitamin B-12, arteriosclerosis more...

Hyperhomocysteinemia and low concentrations of folate and vitamin B6 appear to be associated with an increased risk of carotid artery stenosis in the elderly. Hyperhomocysteinemia is a condition in which plasma levels of homocysteine are higher than normal. Inadequate folate and vitamin B6 concentrations in the blood are associated with the condition. A group of 1,041 people over the age of 66 were divided into two groups based upon the severity of stenosis in two carotid vessels. People with high levels of homocysteine were found to be twice as likely to be in the group with more severe stenosis than those with normal homocysteine concentrations. Higher concentrations of folate and B6 in the plasma were related to less stenosis, while lower concentrations of folate and B6 were found in patients with more severe sclerosis. more...

A low concentration of the thyroid hormone thyrotropin in the blood of persons aged 60 or older may be an independent risk factor for atrial fibrillation (a type of irregular heartbeat). A large study of 2007 persons 60 years old and older followed up for 10 years revealed that those persons with low serum thyrotropin concentrations had three times the risk of developing atrial fibrillation as did persons with normal thyrotropin concentrations. Hyperthyroidism is known to be a risk factor for atrial fibrillation, but older persons with atrial fibrillation usually do not also have hyperthyroidism. Subclinical (too small to be detected easily) hyperthyroidism is known to occur in older persons, and it is marked by a low serum thyrotropin concentration in persons with otherwise normal serum thyroid hormone concentrations. Identifying risk factors for atrial fibrillation is important because it may lead to stroke and decreased heart output. Older persons with low serum thyrotropin concentrations should be monitored for signs of hyperthyroidism and atrial fibrillation. Such persons receiving thyroid hormone therapy should receive lower doses. more...

Increasing age and high blood pressure appear to increase the risk of atrial fibrillation in both men and women. Atrial fibrillation refers to random, rapid contractions of the heart. Of 2,641 women and 2,090 men followed for 38 years as part of The Framingham Heart Study, there were 562 cases of atrial fibrillation. Fifty-three percent of those developing atrial fibrillation were women. Men were 1.5 times more likely than women to develop atrial fibrillation. Diabetes, congestive heart failure and heart valve disease also appeared to increase the risk of atrial fibrillation. Women with valvular disease were more likely to develop atrial fibrillation than men with valvular disease., Objective.--To determine the independent risk factors for atrial fibrillation. Design.--Cohort study. Setting.--The Framingham Heart Study. Subjects.--A total of 2090 men and 2641 women members of the original cohort, free of a history of atrial fibrillation, between the ages of 55 and 94 years. Main Outcome Measures.--Sex-specific multiple logistic regression models to identify independent risk factors for atrial fibrillation, including age, smoking, diabetes, electrocardiographic left ventricular hypertrophy, hypertension, myocardial infarction, congestive heart failure, and valve disease. Results.--During up to 38 years of follow-up, 264 men and 298 women developed atrial fibrillation. After adjusting for age and other risk factors for atrial fibrillation, men had a 1.5 times greater risk of developing atrial fibrillation than women. In the full multivariable model, the odds ratio (OR) of atrial fibrillation for each decade of advancing age was 2.1 for men and 2.2 for women (P more...

Elderly individuals who have mitral annulus calcification (MAC) may have a higher risk for stroke than those who do not. MAC is a chronic disorder characterized by degeneration of the mitral valve of the heart. Of 1,159 individuals between 59 and 90 years old who had not had a stroke, 44 men (10.3%) and 116 women (15.8%) had MAC. Twenty-two individuals (13.8%) with MAC suffered a stroke during an eight-year follow-up period, compared with 51 individuals (5.1%) without MAC. The incidence of MAC was higher among individuals with coronary heart disease or congestive heart failure than among other individuals. Coronary heart disease and congestive heart failure are also risk factors for stroke. The risk of stroke was still twice as high among patients with MAC than among those without, regardless of whether or not they had coronary heart disease or congestive heart failure. more...

Weight cycling (losing and regaining weight with repeated dieting) has been associated with higher mortality, especially from heart disease. However, weight loss from dieting is often not distinguished from weight loss caused by illness. This study included 1,804 women and 1,367 men from the Framingham Heart Study, which was initiated in 1948 to provide detailed information on a carefully observed group over an extended period. Weight and illness were carefully monitored. Persons whose body weight fluctuated often or by a large amount had a higher risk of illness and death due to coronary heart disease than persons who maintained a stable weight. In fact, the risk was comparable to that of being overweight. Among the possible explanations is that persons who are at higher risk for coronary heart disease are also more likely to be on weight-loss regimens. Alternatively, weight-reduction diets and subsequent relapses (regaining weight) may increase risk. If the latter is found to increase risk, it has important public health implications in a society in which half of all women and one-quarter of all men are dieting at any time. This is especially important because the relation between weight cycling and adverse outcomes was greatest among the youngest group, those aged 30 to 44 years. The risk of weight cycling may be greater than that of obesity, suggesting a greater emphasis on skills to maintain weight loss and prevent relapse. (Consumer Summary produced by Reliance Medical Information, Inc.) more...

The Framingham Study showed that diabetes increases the risk of cardiovascular disease and, in particular, disease of the coronary arteries that supply the heart. Factors that increase the risk of coronary disease occur in excess in diabetes. Impaired glucose tolerance, or the reduced ability of the tissues to use glucose, is a common characteristic of diabetes and contributes to an increased risk of coronary disease. Furthermore, diabetic patients may have increased thrombogenic factors, substances that promote the development of thrombi or blood clots. One such thrombogenic factor, fibrinogen, was shown to be important in the occurrence of cardiovascular disease. The role of impaired glucose tolerance and fibrinogen in the development of cardiovascular disease, particularly coronary disease, was assessed in 1,314 patients who were initially free of cardiovascular disease at the beginning of the Framingham study. Diabetes developed in 46 men and 43 women, and blood glucose levels greater than 120 milligrams per deciliter (mg/dL) were detected in 56 men and 53 women. Diabetes was a predisposing factor in 408 major cardiovascular disorders. Compared with nondiabetics, fibrinogen and triglyceride levels, blood pressure, and weight were greater and high density lipoprotein cholesterol was lower in diabetic patients. Although the ability of diabetes to increase the risk of cardiovascular disease is influenced by the presence of other risk factors, impaired glucose tolerance independently contributed to the risk of cardiovascular disease. Fibrinogen values increased with blood sugar levels, suggesting that the diabetic influence on cardiovascular disease may also be related to thrombogenic factors. (Consumer Summary produced by Reliance Medical Information, Inc.) more...