 CVD includes diseases that affect the heart and blood vessels, including congestive heart failure CHF, atrial fibrillation AF, and stroke. CVD may be associated with low levels of n-3 fatty acids and high levels of trans-fatty acids, but more research is needed to determine the role of various fatty acids in the development of CVD. Results from prior studies on this topic have not always been reliable because data from self-reported dietary questionnaires on fatty acid intake have sometimes been inaccurate. A more effective way to measure levels of fatty acids is to analyze blood samples. This study will use blood samples of participants in the Cardiovascular Health Study, a study that examined CVD risk factors in older adults, to determine the link between various fatty acids and the incidence of CHF, AF, and stroke. The results from this study may help researchers identify the dietary factors that influence the development of CVD in older adults. 