Nutritional Determinants of Cardiovascular Disease
研究概览
详细说明
BACKGROUND:
A major component of the prevention and treatment of coronary heart disease is the attenuation of its major underlying process, atherosclerosis, which brings about myocardial ischemia. In exploring the determinants of atherosclerosis, a diet-heart hypothesis has emerged. Simply stated, the hypothesis is that the excessive ingestion of dietary fat, notably total fat, saturated fat and cholesterol and lowered intakes of other nutrients including unsaturated fatty acids and possibly soluble fiber lead to the elevation of serum LDL-cholesterol which causes atherosclerosis. Support of the diet-heart hypothesis is available from epidemiologic, laboratory, and clinical research.
In spite of a broad range of data supporting the diet-heart hypothesis, the importance of diet is often challenged. Cited in this controversy are population-based, cross-sectional studies which have provided conflicting data. Several studies including an early report from Framingham and the Tecumseh Study have failed on cross-sectional analysis to link dietary variables to serum cholesterol, lipoproteins or coronary heart disease rates. The genetic and possible dietary homogeneity in these populations and methodological weaknesses inherent in singe serum cholesterol and dietary assessments have been posed as possible explanations for these differing results.
Difficulties in confirming the diet-heart hypothesis across existing literature may arise for several reasons: methodological problems inherent in estimating nutrient intake; difficulties associated with characterizing a behavior as complex as food purchasing; wide intraindividual variation in nutrient intake that make single day estimates of nutrient intake difficult to interpret; dissimilarities among dietary data collection techniques; varying lengths of followup for the observation of outcome variables in longitudinal epidemiologic studies; differing methods of lipid measurement or the lack of lipoprotein subfractionation. The Framingham data provide a unique opportunity to test the diet-heart hypothesis both cross-sectionally and longitudinally, to develop models for studying diet and heart disease relationships, and to establish the importance of dietary variables in atherogenesis and the morbidity and mortality of heart disease.
DESIGN NARRATIVE:
The associations between nutritional variables and major atherogenic risk factors including dyslipidemia, elevated blood pressure, impaired glucose tolerance, and overweight were investigated cross-sectionally in the total Framingham Offspring Study cohort of 3,800. The independent, quantitative effects of dietary factors on the prediction of cardiovascular morbidity and mortality were explored longitudinally in two samples of the original Framingham cohort at 20 and 30 years of follow-up. Six major steps were followed in each set of analyses: dimension reduction using cluster and factor analysis; zero order independent nutrition variable analyses; stepwise multiple regression of independent variables; specification of overall regression models; stability and validity testing; the addition of intervening variables using multiple regression techniques. Multivariate analyses of the dependent variables were conducted to determine associations and interactions among these variables.
The study completion date listed in this record was obtained from the "End Date" entered in the Protocol Registration and Results System (PRS) record.
研究类型
参与标准
资格标准
适合学习的年龄
接受健康志愿者
有资格学习的性别
描述
学习计划
研究是如何设计的?
合作者和调查者
出版物和有用的链接
一般刊物
- Posner BM, Franz MM, Quatromoni PA, Gagnon DR, Sytkowski PA, D'Agostino RB, Cupples LA. Secular trends in diet and risk factors for cardiovascular disease: the Framingham Study. J Am Diet Assoc. 1995 Feb;95(2):171-9. doi: 10.1016/S0002-8223(95)00043-7.
- Campos H, Willett WC, Peterson RM, Siles X, Bailey SM, Wilson PW, Posner BM, Ordovas JM, Schaefer EJ. Nutrient intake comparisons between Framingham and rural and Urban Puriscal, Costa Rica. Associations with lipoproteins, apolipoproteins, and low density lipoprotein particle size. Arterioscler Thromb. 1991 Jul-Aug;11(4):1089-99. doi: 10.1161/01.atv.11.4.1089.
研究记录日期
研究主要日期
学习开始
研究完成 (实际的)
研究注册日期
首次提交
首先提交符合 QC 标准的
首次发布 (估计)
研究记录更新
最后更新发布 (估计)
上次提交的符合 QC 标准的更新
最后验证
更多信息
此信息直接从 clinicaltrials.gov 网站检索,没有任何更改。如果您有任何更改、删除或更新研究详细信息的请求,请联系 register@clinicaltrials.gov. clinicaltrials.gov 上实施更改,我们的网站上也会自动更新.