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Keynote Address: How Health Behavior Relatesto Risk Factors

John W. Farquhar, MD

IntroductionMuch has been discovered through cardiovascular

disease research about health behavior and risk factors,and for the most part the causal links and their physi-ological mechanisms are quite well understood. I willgive here only a brief review of the traditional linkagesbetween health behavior and risk for cardiovasculardisease. My main purpose will be to present a broad-ened view of behavior and risk factors by consideringmany elements of society that influence the healthbehavior of individuals within that society. A subtitle ofthe paper could be "How Society's Health BehaviorAffects Risk for Cardiovascular Disease."

In covering these topics I will describe some recentfavorable national changes in risk factors and I will thendiscuss behavior change theories and barriers to change,covering both individual and societal factors.

Health Behavior and Cardiovascular Disease RiskFactors: The Traditional View

Hypertension, various atherogenic blood lipid pat-terns, smoking, and sedentary lifestyle are most com-monly listed as major cardiovascular disease risk factors,with male-pattern obesity, diabetes, and certain psycho-social attributes such as hostility, anger, and job strainas additional factors. Some of these risk factors (ie,smoking and sedentary lifestyle) are behaviors and riskfactors in their own right, whereas hypertension, dyslip-idemia, obesity, and diabetes have both behavioral andgenetic antecedents.Our traditional views of linkages between behavior

and risk change as new discoveries are made. Forexample, we can cite the behavior of eating more fruitsand vegetables as the cause of decreased atherogenicityof the low-density lipoprotein molecule induced bydietary antioxidants. So health behavior often stays inthe loop as new research unfolds. As another example,one could predict that continued research in psychoso-cial factors, such as hostility, anger, and job strain, willlead to a more clear and sophisticated understanding ofthe relation between health behavior and cardiovasculardisease risk. Furthermore, discoveries about insulinresistance and small dense LDL are also among manyexamples of a recent increase in knowledge of riskfactors; in these examples we can continue to identify abehavior (physical inactivity) as a contributor to malepattern obesity and to both insulin resistance andincreased levels of small dense LDL.

Health Behavior and Cardiovascular Risk Factors:An Expanded View

The less explored and, in my view, more importantquestion is, what behaviors within society at large shape

the behavior of individuals? Persuasion, modeling, andthe presence of incentives or disincentives all influencebehavior.1 These relations are depicted in Fig 1, whichshows the main features of Bandura's social cognitivetheory with its emphasis on self-efficacy.

Considering this theory and its supporting empiricalfoundations, one can readily comprehend that advertis-ing, cost of cigarettes, and the presence or absence ofthe modeling or persuasive behavior of peers willstrongly influence smoking behavior. In a study from ourcenter on adolescent substance use in tenth-graders, itwas found that use of any substance (cigarettes, chewingtobacco, clove cigarettes, PCP, LSD, cocaine, heroin)was strongly predicted by certain social environmentalfactors.2 The use of marijuana by friends (an example ofmodeling) was the strongest predictor for both boys andgirls. Perceived safety of cigarette smoking was impor-tant to both boys and girls, and among girls perceivedattitude of adults toward smoking also made a minorcontribution. Certainly advertising, peer influence, andmodeling by peers and adults contribute to these atti-tudes. This study and others emphasize the potential forpreventing the adoption of various harmful behaviors,including substance abuse, through social-pressure re-sistance training methods that teach young people howto recognize and resist the influences of advertising andtheir peers.3 In another sense, it is noteworthy thatfactors such as school performance and parents' level ofeducation were also reasonably strong predictors ofsubstance abuse in the stepwise regression.2 This indi-cates that social environmental factors extend beyondpeer pressure to include broad and multiple socialforces that determine social norms. Thus, broader socialchanges that go beyond individual skills training maywell be needed to solve many problems related to healthbehavior.Another aspect of the broadened view of the relation

between behavior and risk factors leads to the question,who in the population needs to change for patterns ofdisease to be affected? In our health care system theoveruse of services and the high rate of cardiovascularevents among individuals at high risk can both leadlogically to a belief that the major yield will come fromthe so-called "high-risk" approach. Most recommenda-tions from the Surgeon General4 and other bodies-56have included attention to lower-risk individuals or theentire population. This so-called "public health" ap-proach recognizes that precursors of a high-risk statusare found at earlier ages or lower risk levels and thatprimary prevention is needed as part of a comprehen-sive approach. However, in my view, the scientific

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Farquhar Keynote Address 1377

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FIG 1. Representation of Bandura's social cognitive theory,with emphasis on self-efficacy (SE).Adapted from Bandura, A. Self-efficacy: toward a unifying

theory of behavior changes. Psychol Rev. 1977;84:191-215.

foundation for the public health approach has never

been made more clearly than by Geoffrey Rose in a

recent publications His central finding is that mean

levels of various attributes (alcohol consumption, bloodpressure, body mass index) predicted the proportion ofthe population at "high risk" (the proportion defined as

being alcoholic, hypertensive, or obese). Similar findingsby Blackburn8 have been shown for blood cholesteroldistributions in different countries. Rose7 therefore givesthe public health approach greater legitimacy as largernumbers of attributes are shown to follow the "distribu-tion rules" for blood cholesterol level. He points out thathis conclusions about blood pressure were not possibleuntil the Intersalt project9 gave us comparable surveymethods in the 52 countries studied. These data allow usto ask whether a sufficient proportion of total effort incardiovascular disease prevention and control is beingdevoted to the true public health approach. A radicalview would be that all high-risk problems would be solvedif we paid attention only to the low and middle parts ofthe distribution curve for any risk factor under study, as

this shift of the curve to the left would drag in the tail ofskewness, so to speak. Thus, the high-risk individualswould be relabeled as low- or medium-risk. I would labelthis as an experiment that will never be done because ofethical constraints as well as a lack of conviction by theexperimenters. Nonetheless, it is clear that strong effortsto include a comprehensive total-population approachare absolutely essential for success in control of cardio-vascular disease. In a later section I describe some of theobstacles to achieving adequate primary prevention byhighlighting barriers to regulatory change, an essentialcomponent of the broadest approach.

National Changes in Health Behaviors, RiskFactors, and Cardiovascular Disease OutcomesMuch has happened at the national level to make us

optimistic about the possibility of achieving widespreadand important differences in health behavior. If condi-tions are right, these changes can be quite rapid. As an

example, seat-belt use in the United States quadrupled(from 17% to 65%) from 1982 to 1987 (The Los AngelesTimes. October 5, 1987). These changes occurred at atime of increase in both education and legislation.When the time is ripe, good things can happen, andhealth behaviors are not always stubbornly or hopelesslyintransigent.

Nationwide change in cardiovascular disease mortal-ity has been similarly dramatic but has occurred over a

much longer time frame. Stroke mortality has declinedslowly and steadily since 1940, and by 1989 had de-creased by 73%. Coronary heart disease mortality hasshown a different pattern, with a gradual rise from 1940to 1963 and a steeper and continuing decline since then.The fall from 1963 to 1989 was an impressive 53%.10The question of what proportion of these dramatic

changes in cardiovascular disease are attributable tochanges in diet, smoking, and exercise behavior isdifficult to answer, but both stroke and coronary heartdisease death rates began to decrease before wide-spread use of pharmacological agents occurred. It is ofinterest that the landmark Surgeon General's Report onSmoking and Health of 1964 appeared shortly beforethe decline in coronary heart disease began. Of coursethe large decrease in smoking prevalence (an approxi-mate 32% fall since 1970) is responsible for some of thedecline in heart disease.10 Similarly, blood cholesterollevels of the US population have declined coincidentwith decreases in consumption of saturated fat andcholesterol from animal products."1 Blood pressure con-trol has also improved markedly during the past twodecades. Certainly use of pharmacological agents hasplayed a major role in the changes in hypertensionprevalence, but during this time food-grade salt saleshave also declined by 36%.12 In the broadened view ofhealth behavior, the increased use of pharmacologicalagents is still attributable to changes in behavior acrossmany levels: (1) the patient's adherence to medication,(2) changes by healthcare professionals in education,screening, prescribing, and monitoring, and (3) changesin education and screening by private and governmenthealth agencies.The main lesson to be learned from the revolutionary

changes in cardiovascular diseases outcomes is thathealth behaviors and risk factors can be changed. Giventhese victories, can we now turn our attention away fromcardiovascular disease? By no means. We can take pridein the knowledge that the United States' relative positionin cardiovascular disease has fallen from first in the worldin the 1950s to 15th for both men and women of 33industrialized countries in 1990 (ranked from highestrate to lowest).10 However, in 1990 Canada ranked 28thand 27th for men and women respectively in this samegroup.10 Other comparisons show that there are largedifferences between different states and regions and fordifferent ethnic and income groups in the United States.Comparison with Canada and differences within our owncountry point clearly to a continued need for aggressiveaction to improve the health-related behaviors of themany individuals and groups involved and particularly ofcertain subgroups of our population. The following sec-tion identifies barriers to widespread behavior changeand how some of them might be overcome.

Barriers to Behavior ChangeBarriers to health behavior change are many, and a

few have been mentioned in this paper. A partial list, inno special order, includes (1) inertia and lag related tosocial norms, peer pressure, and the expected delays inadoption of innovations,1,13 (2) biological determinants,including addiction to nicotine, (3) lack of knowledge,incentive, or skills for change, (4) societal factors thatlead to sedentary lifestyle or job strain and psychosocialstress, (5) economic barriers or inadequate training of

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providers that disallow health promotion activities anddeny access to clinical preventive sources, (6) economicfactors that distort our public media, such as magazinesthat do not accept articles on the hazards of smoking, and(7) economic factors that influence politicians to delayregulatory changes that would otherwise facilitate bene-ficial health behavior change (such as increased excisetaxes on tobacco). A longer list is possible, and of thosementioned only a few will be discussed in this statement.

International trade policies affect health in ways thatare not often fully appreciated. In 1992 the WorldHealth Organization estimated that 10% of the currentworld population, or 550 million people, would dieprematurely because of cigarette smoking. My ownprediction is that this is an underestimate because of theaccelerating adoption of cigarette smoking by residentsof developing countries. Our center is currently involvedin training Czech medical and public health scientistsand educators in the community approach to cardiovas-cular disease prevention and control. During 1992 to1993 it has become abundantly clear that Prague isvirtually blanketed by an advertising blitz by Americancompanies, with street cars, store windows, and outdoorcafe umbrellas promoting the now-desirable Westernbrands. In early 1992 Phillip Morris outbid all rivals bya large margin to pay $413 million to purchase Tabak,the state-owned tobacco company, in what was thenCzechoslovakia. A few quotes from The Wall StreetJournal are testimony to the reason for the purchase:"Tobacco companies race for advantages in EasternEurope while critics fume"; "So far Phillip Morrisseems to be ahead. It has established operations ineastern Germany, Hungary, Czechoslovakia and Russiaand is negotiating for plants in Poland"; "Phillip Mor-ris's biggest success so far has been in snatching Tabak,the Czechoslovak tobacco monopoly, from its rivals lastApril in one of the East's most acrimonious privatiza-tions. In so doing, it acquired popular Czech brands andabout 56% of a market of 30 billion cigarettes per year"(The Wall Street Journal. December 28, 1992).Worldwide promotion of cigarettes and other tobacco

products such as smokeless tobacco is acceleratingcoincident with growing recognition of their healtheffects and of their economic penalties in healthcarecosts, decreased productivity, and diversion of usableincome by the end users. An important barrier tochange is the use of tobacco companies' enormousrevenues to promote their products by forcing othercountries, under threat of trade retaliation, to acceptboth these products and their advertising. The reasonfor the enormous revenues stems from the fact that theaddictive power of nicotine itself allows charges to theconsumer that exceed normal market cost. These extrarevenues also provide funds that can be used for con-tributions to politicians at local, state, and federal levelswho oppose legislation that would decrease tobacco use.A recent publication, "The Congressional Addiction toTobacco: How the Tobacco Lobby Suffocates FederalHealth Policy," presents evidence for almost a dozen"victories" of the tobacco lobby on legislation regulatingtobacco exports, excise taxes, labeling, tax deductionsfor tobacco advertising, prices charged to the military,and health education.14A specific barrier is that the portion of the retail cost

of cigarettes due to taxes has been kept lower in the

TOBACCO TAXATION IN TEE UNITED STATESAVEAGE CIGArETE TAX AS A % OF RAIL PRUCIC

1966 1962 1968 1374 1980 1986 1992

FIG 2. Historical trends in tobacco taxation in the UnitedStates.From Sweanor D. The Tax Burden on Tobacco? An

Analysis of Tobacco Taxation Policy in the United States.Ottawa, Canada: Non-Smoker's Rights Association (Can-ada); 1993.

United States than in any other country, thus denyingtax revenue to governments and preventing the disin-centive that would exist if tax increases raised the cost ofcigarettes to a considerably higher level. Fig 2 showsthat the tax burden on tobacco remained at about 48%of the total cost of cigarettes from 1955 to 1970 but hasfallen steadily from then to about 25% by 1992. Thefailure to keep taxes in proportion has been attributedto the political influence of the tobacco lobby.14

Fig 3 shows how the United States compares to 18other countries in taxes per pack of cigarettes.'5 Withthe exception of Spain, all these countries have taxesfrom two to eight times as high as in the United States(where the average tax is 46¢ a pack), although there isconsiderable variation among states. The average tax inthese 18 other countries is about US $2.00 per pack, afigure that I believe should be our short-term goal, witheven higher taxes in the future.

If we raise taxes on cigarettes, will smoking behaviorbe influenced? California's recent experience suggeststhat it will. Fig 4 shows a clear decline in the number ofpacks sold there immediately after taxes were raised by25¢ per pack.16Between 1989 and 1991 cigarette smoking declined by

17%, more than twice the United States average.17 Aregression analysis showed that 5% to 7% of the declineduring the first year of the tax was secondary to the taxalone.'8Based on this and considerable other data, price

elasticity of demand for cigarettes is about -0.4 foradults'9 and about -1.44 for adolescents.20 Thus evenan increase as small as 10% in cigarette prices (less thanthe new California tax) would likely lead to a 4%decline in cigarette consumption for adults and a 14%

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Farquhar Keynote Address 1379

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decline for adolescents. If a $2.00 per pack increasewere to occur, teenage smoking rates could fall by theimpressive degree of 46%.Of course, other regulatory changes are needed to

control smoking and would interact with and ultimatelydepend on continued vigorous education and cessationefforts. For example, despite the cost of cigarettes, pre-vention of adolescent smoking would predictably losemuch of its impact if the majority of adults over age 30were smokers, as was the case in the United States in themid-1960s.The 1988 study by Altman et a121 on the effects of a

low-cost campaign in California's Santa Clara Countypoints to the value of educating merchants about ob-serving the law banning cigarette sales to minors.21 Inthis study cigarette sales were reduced by about twothirds, while vending machine sales were unaffected.This example shows the value not only of enforcingexisting laws (in this case through education and per-suasion rather than threats) but also the need for newregulations (banning all vending machines in sites opento the underage public).The preceding section was one-sided in its focus on

tobacco. It is therefore important to list a few other topics

-B

A.

2.5 3 3.5

FIG 3. Total taxes per 20 ciga-rettes in US dollars, July 1993.Adapted from Non-Smoker's

Rights Association (Canada),personal communication, 1993.

for which there are regulatory and environmental barriersto change: Nutrition. (1) Labeling laws, (2) provision ofhealthy food choices (coupled with education) for stu-dents and other recipients of institutional food, (3) thelack of connection between national agricultural policyand health policies, and (4) restaurant and retail foodmarket policies. Physical activity. (1) Lack of consistentpolicies for promoting physical education and opportuni-ties for aerobic exercise in schools, (2) the geographicaland regulatory factors that affect the ready availability ofsites for walking and other forms of physical activity thatare safe, convenient, and free of charge, and (3) factors incity structure, employment, and transportation policy thatlead to long commuting times that interfere with time forphysical activity. Psychosocial health. (1) Worksite factorsthat lead to job strain, (2) lack of opportunities for jobretraining after termination of employment, (3) lack ofopportunities for education and treatment of substanceabuse, (4) lack of affordable housing and medical care, (5)exposure to violence in television and movies, and (6) lackof community support for and regulatory measures thatpromote family stability.Many of these barriers, and others, are addressed in

the 64 recommendations for cardiovascular disease pre-

14

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TAX Increas6 v5 ,.2o ' ._.2o ' 1..2i h. 2o u.1,' v s ' X.2mcu.2tI' I.'1

FIG 4. Decrease in per cap-ita cigarette use following theCalifornia tax increase ofJanuary 1989.From Burns D, Pierce JP.

Tobacco use in California1990-1991. Sacramento,Calift California DepartmentofHealth Services; 1992.34.

ntJWJSW J51 JdIIW J~o Jtoy9 JUo-@ Jm- Joel dJO dDO Jo-v JU-U

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1380 Circulation Vol 88, No 3 September 1993

vention contained in the recently released VictoriaDeclaration on Heart Health (produced by the Advis-ory Committee to the first International Heart Healthconference, held in Victoria, Canada in May 1992.)6 Ichaired this committee and Dr. David MacLean ofDalhousie University cochaired it. We were aided by 19others from different disciplines and many differentcountries. Three examples from the Victoria Declara-tion on Heart Health follow.

Recommendation 4-Governments provide schoolswith support and resources they need to carry outeffective health and heart health education programs

and to provide facilities and opportunities for dailyphysical activity.

Recommendation 21-Governments a) adopt legisla-tion to end the advertising and promotion of tobaccoproducts and encourage those in the tobacco industryto make the transition to other areas of economicactivity; b) use taxation liberally as an instrument todecrease tobacco use; c) apply at least 10% of the taxesraised through the sale of tobacco products to healthpromotion including anti-tobacco education.

Recommendation 62 -The private sector, especiallythe agriculture, food and pharmaceutical industries,continually reexamine their corporate marketing andproduction strategies to ensure that they supportpublic policies for the prevention and control ofcardiovascular disease.

All of the Victoria Declaration recommendationsaddress the need for comprehensive approaches thatcombine education, regulation, environmental change,and cooperation among science, government, and theprivate sectors to achieve its goals.

ConclusionsThe evidence presented in this statement for changes

that have already occurred in the United States inhealth behavior, risk factors, and cardiovascular diseaseis cause for optimism that continued decreases in car-

diovascular risk can be achieved. However, great pessi-mism can be engendered by awareness of barriersintrinsic to social norms and commercial and politicalpressures. The view of health behavior presented heretherefore invites a broadened set of actions by healthcare professionals that adds advocacy for political actionto education aimed at the entire public, with emphasison precursors to risk factors. If we accept the need tobroaden our efforts in education, advocacy, and politicalchange, we cannot do it without recognizing the roletelevision plays in our lives. As Neil Postman has said inhis recent provocative book,Amusing Ourselves to Death,television is our culture's principal mode of knowingabout itself.22 We all certainly accept television's profi-ciency in letting us know what to buy, but we have yet toacknowledge its legitimate role or to harness its powerin aiding us in our quest for health.The ultimate optimism that our quest may be realized

lies in this quote from the founder of social cognitivetheory, Bandura,23 who said, "But it is because of theirconsiderable plasticity and powers of cognition that hu-mans have an unparalleled capacity to become many

things."23The Victoria Declaration's "Call for Action" states,

"Cardiovascular disease is largely preventable. We have

the scientific knowledge to create a world in which mostheart disease and stroke can be eliminated." In thespirit of Bandura's statement, one of the "many things"we could become is a world that has achieved what wasseen as possible in that call for action.

References1. Bandura A. Self-efficacy: toward a unifying theory of behavior

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KE, Maron DJ, Maccoby N, Farquhar JW. Perspectives on ado-lescent substance use: a defined population study. JAMA. 1987;258:2072-2076.

3. Killen JD. Prevention of adolescent tobacco smoking: the socialpressure resistance training approach. J Child Psychol Psychiatry.1985;26:7-15.

4. The Surgeon General's Report on Nutrition and Health. Washington,DC: US Dept of Health and Human Services, Public HealthService; 1988.

5. Expert Panel on Detection, Evaluation, and Treatment of HighBlood Cholesterol in Adults. Summary of the Second Report ofthe National Cholesterol Education Program (NCEP) ExpertPanel on Detection, Evaluation, and Treatment of High BloodCholesterol in Adults (Adult Treatment Panel II). JAMA. 1993;269:3015-3023.

6. The Victoria Declaration on Heart Health. Declaration of theAdvisory Board, International Heart Health Conference, Victoria,Canada, May 28, 1992. Ottawa, Canada: Department of Healthand Welfare, Canada.

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8. Blackburn H. Diet and mass hyperlipidemia: a public health view.In: Levy RI, Rifkind BM, Dennis BH, Ernst ND, eds. Nutrition,Lipids, and Coronary Heart Disease:A Global View. New York, NY:Raven Press; 1979.

9. Intersalt: an international study of electrolyte excretion andblood pressure: results for 24 hour urinary sodium and potassiumexcretion. Intersalt Cooperative Research Group. BMJ. 1988;297:319-328.

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11. Friend B, Page L, Marston R. Food consumption patterns in theUnited States, 1909-13 to 1976. In: Levy RI, Rifkind BM, DennisBH, Ernst ND, eds. Nutrition, Lipids, and Coronary Heart Disease:A Global View. New York, NY: Raven Press; 1979.

12. Roccella EJ, Horan MJ. The National High Blood Pressure Edu-cation Program: measuring progress and assessing its impact.Health Psychol. 1988;7(suppl):297-303.

13. Rogers EM. Diffusion of Innovations. 3rd ed. New York, NY: FreePress; 1983.

14. Wolfe S, Douglas C, Wilburn P, Kirshenbaum M, McCarthy P,Baure A, McKnew D. The congressional addiction to tobacco: howthe tobacco lobby suffocates Federal health policy. A report byPublic Citizen's Health Research Group and the AdvocacyInstitute, Washington, DC, October 1992.

15. Saving lives and raising revenue: the case for major increases inState and Federal tobacco taxes. Washington, DC, Coalition onSmoking OR Health, January 1993.

16. Burns D, Pierce JP. Tobacco use in California 1990-1991. Sac-ramento, Calif: California Department of Health Services; 1992:34.

17. Burns D, Pierce JP. Tobacco use in California 1990-1991. Sac-ramento, Calif: California Department of Health Services; 1992:31.

18. Flewelling RL, Kenney E, Elder JP, Pierce J, Johnson M, Bal DG.First-year impact of the 1989 California cigarette tax increase oncigarette consumption. Am J Public Health. 1992;82:867-869.

19. Smoking and Health in the Americas: A 1992 Report of the SurgeonGeneral, in Collaboration With the Pan American Health Organi-zation. Executive Summary. Atlanta, Ga: US Dept of Health andHuman Service, Centers for Disease Control; 1992. DHHS publi-cation (CDC) 92-419.

20. Lewit EM, Coate TJ, Grossman M. The effects of governmentregulation on teenage smoking. J Law Econ. 1981;24:545 -569.

21. Altman DG, Foster V, Rasenick-Douss L, Tye JB. Reducing theillegal sale of cigarettes to minors. JAMA. 1989;261:80-83.

22. Postman N. Amusing Ourselves to Death. New York, NY: VikingPress; 1985.

23. Bandura A. Social Foundations of Thought and Action: A SocialCognitive Theory. Englewood Cliffs, NJ: Prentice Hall; 1969.

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J W Farquharbehavior relates to risk factors.

Behavior change and compliance: keys to improving cardiovascular health. How health

Print ISSN: 0009-7322. Online ISSN: 1524-4539 Copyright © 1993 American Heart Association, Inc. All rights reserved.

is published by the American Heart Association, 7272 Greenville Avenue, Dallas, TX 75231Circulation doi: 10.1161/01.CIR.88.3.1376

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