Click for next page ( 182

The National Academies | 500 Fifth St. N.W. | Washington, D.C. 20001
Copyright © National Academy of Sciences. All rights reserved.
Terms of Use and Privacy Statement

Below are the first 10 and last 10 pages of uncorrected machine-read text (when available) of this chapter, followed by the top 30 algorithmically extracted key phrases from the chapter as a whole.
Intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text on the opening pages of each chapter. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.

Do not use for reproduction, copying, pasting, or reading; exclusively for search engines.

OCR for page 181
24. Cardiovascular Disease Heart disease and stroke are the first and fourth leading killers of Americans. Since 1950, death rates for these two cardiovascular diseases have declined substantially: 47 percent for heart disease and 69 percent for stroke. As a result, stroke has dropped from the third to the fourth leading cause of death.t To maintain these impressive improvements, however, 42 witnesses called for continued efforts aimed at reducing the primary risk factors associated with cardiovascular disease (CVD), high blood pres- sure (hypertension), high serum cholesterol level (hypercholesterolemia), and smoking-as well as the secondary risk factors of sedentary lifestyles and obesity. Because three of these five risks are treated in some depth in separate chapters within this docu- ment (tobacco, Chapter 10; nutrition, Chapter 12; and physical activity, Chapter 13), the focus here is primarily on hypertension and high cholesterol. Although these two risks are associated with separate genetic and environmental factors, several common approaches to their control are identified, as are several common populations that require special attention. Dietary change is the strategy raised most often for combating both high blood pressure and high cholesterol; food labeling also is mentioned repeatedly as a way to help individuals adopt healthy diets. Other strategies to prevent both hypertension and high cholesterol include public and professional awareness, screening, follow-up, and compliance, according to witnesses. Minorities, especially Hispanics and Blacks, are seen as particularly- vulnerable to CVD. For example, Michael Crawford of the University of Texas Health Science Center at San Antonio says that from 1970 to 1980 in San Antonio, among males aged 35 to 44, non-Hispanic Whites experienced an 8 percent decline in heart disease mortality, whereas Hispanic males experienced a 62 percent rise. He states, "across all age categories we see the same trend; that the Hispa- nic male is not experiencing this decline to the extent that the non-Hispanic White is, and in some age categories, the younger men have increased in this mortality." Crawford calls for education designed especially to encourage Hispanic men to alter their lifestyles. (~743) Also singled out as needing special attention are the elderly, the medically or economically disad vantaged, and males. Although some risk factors for CVD can be found in young children and teenagers (#182; #261), disagreement exists on how rigorously and how early interventions should be started. A number of testifiers see funding for research and for surveillance as a problem in need of attention be- tween now and the year 2000. HYPERTENSION Several witnesses noted that when the 1990 Objectives were written, high blood pressure was defined as 160/95 mm/Ha or higher. Since then, however, studies have demonstrated the value of treating mild hypertension, and the definition of high blood pres- sure has changed to 140~90. The objectives should reflect that change, according to witnesses. (~591) To help prevent hypertension, the American Heart Association (AMA) dietary guidelines call for efforts to reduce sodium intake. Sodium intake currently far exceeds the physio- logical needs of healthy Americans. The body can function quite normally and indefinitely with sodium intakes of less than 0.2 gram per day. Present consumption has been estimated at 4 to 5 grams per day. Cross-cultural studies show a clear relationship between the incidence of high blood pressure and the sodium content of the habitual diet. The AHA believes that the epidemiologic evidence is compelling and that a reduction of sodium intake to 1 gram per 1,000 calories, not to exceed 3 grams, Is safe, feasible, and likely useful in prevention of high blood pressure in many Americans. This represents 2 grams of sodium per day for the average person consuming 2,000 calories.2 (~636) The Salt Institute, however, says that new data about the relationship between sodium or salt intake and hypertension also argue for changing the 1990 Objectives on that subject. On the basis of these studies, researchers concluded that for two-thirds of the population a general recommendation to reduce sodium chloride intake would have no benefit and could be harmful. (~082) "It seems clear that the question of diet and hypertension is so complicated Cardiovascular Disease 181

OCR for page 181
and dependent on individual (probably genetic) factors that a general population dietary guideline is inap- propriate," according to Richard Hanneman. (~082) Although only one-third of the population is thought to be salt sensitive, a reviewer points out that no one knows who those 80 million Americans are. Because there is no known benefit from consuming large amounts of salt, and substantial benefit can be gained by a large number of people from cutting down, many believe that a general recommendation to cut down salt intake makes sense. (#800J California Department of Health Services Director Kenneth Kizer underscores the point that follow-up is an essential component of screening programs. He cites 1983 data that 90 percent of California adults had their blood pressure measured in the previous two-year period, but of those referred for evaluation and diagnosis, many do not complete the referral. Among those diagnosed and under treatment, many do not adhere strictly to the treatment plan and remain uncontrolled. Only a small fraction of hyper- tensive adults are achieving and maintaining control of their blood pressure levels, according to Kizer. As a result of these figures, the thrust of California's hypertension control program is enrolling and main- taining hypertensive individuals in a health care setting that promotes adherence to control programs. (#591J The American Association of Occupational Health Nurses emphasizes worksite intervention and cites more optimistic figures. The worksite is an ideal place for screening, education, intervention and prevention services. Employers benefit from decreased incidence or early detection of chronic health problems through reduced health insurance and disability costs and reduced absenteeism. Providing ser- vices at the worksite is cost effective and offers opportunities for increased compliance and better treatment outcomes. A recent review of several worksite hypertension control programs documented that 88 to 90 percent of hyperten- sion employees treated at the worksite con- trolled their blood pressure. The success of these programs, which included detection, refer- ral, treatment and follow-up, rested strongly upon the skills of the health care providers- primarily nurses. (~558) 182 Healthy People 2000: Citizens Chart the Course HIGH BLOOD CHOLESTEROL Additional testimony on reducing serum cholesterol focused on limiting the intake of both dietary fat and dietary cholesterol, and as a secondary preventive measure, on expanding screening programs to identify individuals with high cholesterol or specific dietary goals. The American Heart Association reports that a certain amount of cholesterol is necessary in the body for building cell walls and other functions, but the liver supplies sufficient cholesterol to meet all of the body's own needs. (#636) Joseph Stokes of Boston University says that an average total cholesterol value of 190 milligrams per deciliter in adults more than 18 years old is a realistic goal for the year 2000. (~627) Many studies have related dietary fat and choles- terol to blood cholesterol, and blood cholesterol to cardiovascular disease. Because of this, the AHA re- commends monitoring personal consumption of cho- lesterol and keeping it less than 100 milligrams per 1,000 calories in the diet, not to exceed 300 mil- ligrams per day.3 (~636) Stokes also favors incorporating the AHA dietary guidelines for fat into the Year 2000 Health Objec- tives. He says that the percentage of calories from fat should be less than 30 percent; the percentage of calories from saturated fat should be less than 10 percent; and the ratio between polyunsaturated and saturated fatty acids in the diet should be ap- pro~mately 1:1. (#627) Leslie VanDermeer, an occupational health nurse, says that screening of serum cholesterol levels should be available to all employees working at a company with a medical unit or a nursing department on the premises. (~217) Other witnesses also emphasized the importance of follow-up of those with high cholesterol readings. The American Heart Association testimony calls for federal funds to help states develop and implement cholesterol screening programs. It emphasizes that such programs must involve not only screening but also appropriate referral and treatment activities. (#636) Several witnesses referred to the need for in- dividuals to reduce their fat and cholesterol intake. Several also favored additional research into the link between diet and cholesterol. Witnesses also endorsed efforts to increase the

OCR for page 181
percentage of food products that are labeled according to their fat and cholesterol content. Dietitian Marilyn Guthrie says that the food industry should cooperate not only in labeling food, but also in lowering the amount of fat, saturated fat, and cholesterol in the products. She also recommends more support for businesses to offer cholesterol-lowering programs. Better data on the cost versus benefits of initiating dietary changes could provide the impetus for more structured programs. (#077) Chapter 12 contains a more detailed discussion of nutrition and cholesterol control. TARGET POPULATIONS Many witnesses emphasized the need to develop ob- jectives to target high-risk groups and those who are especially hard to reach. These include Blacks, Hispanics, the elderly, males, and children, along with the medically or economically disadvantaged. Also, in many instances, individuals fall into two or more of these categories, multiplying many times the problems faced in changing their lifestyles or getting them into and maintaining treatment. For example, Kizer says that data from two statewide surveys in California demonstrate that priority must be given to ethnic minorities with a high prevalence of hypertension and to the medically or economically disadvantaged. He believes that adult males within these groups, in particular, should be targeted. (#591) Blacks Michael Jarrett of the South Carolina Department of Health and Environmental Control says the Year 2000 Health Objectives should specifically address aware- ness among high-risk groups such as Black males. (~108) John Thomas and William Neser of Meharry Medical College also emphasize the increased preva- lence of hypertension among Blacks and note that although dramatic decreases in cardiovascular disease and hypertension have occurred in the overall popula- tion, the Black community has not seen that kind of decline. Possible risk factors for all groups, according to Thomas and Neser, are parental hypertension, weight gain, and smoking. Weight control, they em- phasize, is an important nonpharmacological risk reduction measure. (i#961) Hispanics Studies have shown that although Hispanics may have a better general knowledge about hypertension than Blacks, they still lag behind Whites in the percentage of known hypertensives who are taking medication and whose hypertension is under control.4 Crawford speaks of the high cholesterol levels among Hispanics in San Antonio. The problem is more pronounced in Hispanics than in non-Hispanic Whites across socio- economic groups. According to a local study among those with elevated cholesterol levels, fewer Hispanics are aware of it than non-Hispanic Whites, he testified. Of those in both groups who are aware, only one- fourth are under treatment and, of these, only about 40 percent have their levels controlled. Crawford believes that the problem with high cholesterol may be partially responsible for Hispanics not experiencing the kind of decline in ischemic heart disease seen in the general population in recent years. He called for an objective to reduce the prevalence of moderate- to high-risk cholesterol levels among young Hispanic men. (#743) Elderly The elderly are at special risk for CVD, according to Rosalie Young of Wayne State University: "As a ma- jor killer and disabler of the elderly, heart disease accounts for 45 percent of the mortality, 18 percent of the hospital days, another 18 percent of the bed days, and 10 percent of physician visits of the 65-plus cohort.n Research she conducted for the National Institute of Aging indicates that it also "takes a major toll on the patient's general well being and mental health, and produces substantial physical and mental strain among family caregivers." (~478J A special focus on the elderly is necessary, accor- ding to Rebecca Richards who conducts a wellness program for older adults in Wisconsin. She favors adding an objective to increase public and profes- sional awareness about the risks and appropriate management of hypertension in older adults. Hyper- tension is the leading reason for doctor YiSitS among older adults in Wisconsin, but many physicians still resist treating older people; she cited Cassel and Walsh on the subject: "lithe dogmas that hypertension is a benign disease in old age, that it is a natural Cardiovascular Disease 183

OCR for page 181
result of aging, that old people need higher blood pressure to perfuse aging organ systems, and that antihypertensive therapy is of no value and too dangerous in persons over 65 years of age are all too frequently heard.l's (#183) Children Although several witnesses discussed the apparent relationship between the existence of CVD risk factors in children or teens and later manifestation of the disease, agreement was not reached on how to identify and treat them. Thomas and Neser discuss a study which found that hypertension and weight gain or smoking among Black parents are Significant independent predictors of hypertension among their children; they suggest that "if such individuals were detected during early childhood (5-6 years), intervention could be instituted that could prevent or alter the course of later hyper- tension and thus morbidity and deaths due to hyper- tension and atherosclerotic cardiovascular disease." (~261) However, Darwin Labarthe of the University of Texas Health Science Center at Houston warned that it may be difficult to identify those who will be at high risk in adulthood based on blood pressure or cholesterol levels in adolescence because patterns are not consistent. Cross-sectional survey data from around the world suggest that blood pressure rises during childhood and adolescence, and cholesterol level falls, he says. Therefore, it may not be possible to target individuals for prevention strategies at an early age. (#299) Richard Niwinski, Terry Davis, and Rosemary Yancheck of Chapman College state that even if chil- dren at risk could be identified, some strategies, such REFERENCES as dietary interventions, might not be worthwhile because "not enough data has been collected to show the effect of diet in the age groups from two to twenty-~ve years." Rather, they suggest that educa- tional programs for the parents of these children be considered. (#182) Labarthe says the Southwest Center for Prevention Research is conducting research at the University of Texas that may help determine appropriate inteIven- tions for teenagers. (~299) IMPLEMENTATION The implementation issue that arose most often was lack of funding for research, evaluation, and surveil- lance. The American Heart Association calls for objec- tives that reflect the need for the federal government to continue to dedicate "sufficient funding" to research in cardiovascular disease, Because it is only through continued research that disease prevention and health promotion activities will prosper." (~636) Similarly, the American College of Cardiology proposes objec- tives emphasizing research on cardiovascular disease prevention and application in practice, as well as more physician education in primary and secondary prevention. (#552J Richards says that the ability to comply with antihypertensive medication is a special problem with older people and urges that surveillance and evalua- tion research include older subjects. (#183) Noting that his information collection and client tracking systems have been "deemphasized due to lack of funds and diminished resources," Stephen McDonough of the North Dakota State Department of Health and Consolidated Laboratories indicates that he is thus less able to assess categories of high blood pressure control. (#479) 1. U.S. Department of Health and Human SeIvices: Prevention '86787: Federal Programs and Progress. Washington, D.C.: U.S. Government Printing Office, 1987 2. American Heart Association: Position statement: Dietary guidelines for healthy American adults. A statement for physicians and health practitioners by the nutrition committee. Circulation 77~3~:721A-724A, 1988 3. Ibid. 4. Barrios E, Iler E, Mulloy K, et al.: Hypertension in the Hispanic and Black population in New York City. J Nat Med Assoc 79~7~:749-752, 1987 184 Healthy People 2000: Citizens Chart the Course

OCR for page 181
5. McDonald WJ: Medical, psychiatric and pharmacological topics. Geriatric Medicine, Vol. I. Edited by CK Cassel7 JR Walsh. New York: Springer-Verlag' 1984 TESTIFIERS CITED IN CHAPTER 24 077 Guthrie, Marilyn; Virginia Mason Clinic (Seattle) 082 Hanneman, Richard; Salt Institute 108 Jarrett, Michael; South Carolina Department of Health and Environmental Control 182 Niwinski, Richard; Davis, Terry; Yancheck, Rosemary; Chapman College (San Diego) 183 Richards, Rebecca; North Woods Health Careers Consortium (Wausau, Wisconsin) 217 VanDermeer, Leslie; Hunter College (New York 261 Thomas, John and Neser, William; diehard Medical College 299 Labarthe, Darwin; University of Texas Health Science Center at Houston 478 Young, Rosalie; Wayne State University 479 McDonough, Stephen; North Dakota State Department of Health and Consolidated Laboratories 552 Klocke, Francis; American College of Cardiology 558 Babbitz, Matilda; American Association of Occupational Health Nurses 591 Kizer, Kenneth; California Department of Health Services 627 Stokes, III, Joseph; Boston University 636 Ballin, Scott; American Heart Association 743 Crawford, Michael; University of Texas Health Science Center at San Antonio 800 Stoto, Michael; Institute of Medicine Cardiovascular Disease 185