Profile of self-reported risk factors.
Importance of personal cholesterol level.
Knowledge of desirable total cholesterol level in a healthy adult. To convert cholesterol to millimoles per liter, multiply by 0.0259.
Awareness of national guidelines for cholesterol management. NA indicates don't know or no answer.
Awareness of own cholesterol level. To convert cholesterol to millimoles per liter, multiply by 0.0259.
Sources relied on for cholesterol information.
Timing of discussion about cholesterol with health care professional.
Nash IS, Mosca L, Blumenthal RS, Davidson MH, Smith SC, Pasternak RC. Contemporary Awareness and Understanding of Cholesterol as a Risk FactorResults of an American Heart Association National Survey. Arch Intern Med. 2003;163(13):1597-1600. doi:10.1001/archinte.163.13.1597
Public awareness and understanding of risk factors for atherosclerotic vascular disease are essential for successful primary and secondary prevention. The American Heart Association is committed to reducing cardiovascular disease.
A professional market survey company conducted a structured national telephone survey of English-speaking adults 40 years and older on behalf of the American Heart Association. Regional and sex quotas were imposed on the sample, and responses were weighted to match the 1999 census projections for region of the country, age, sex, and race.
Interviews were completed with 1163 adults 40 years and older. A national probability sample of 1114 was created. Of the final sample, 28.5% were 65 years or older, 56.1% were women, and 86.5% were white. Although 91.2% of respondents stated that it was "important to them personally to have a healthy cholesterol level" (77.6% extremely or very important), 51% did not know their own level. Only 40.2% were aware of national guidelines for cholesterol management, and 53.1% either did not know or overestimated the correct desirable total cholesterol level for a healthy adult. When asked what sources of information they rely on the most, 66.8% identified physicians, while only 3.7% rely primarily on the Internet.
Public understanding of cholesterol management is suboptimal. Physicians have a unique opportunity, on the basis of public attitudes and access, to improve cholesterol education.
CARDIOVASCULAR DISEASE is the leading cause of mortality in the United States, accounting for more than 40% of all deaths.1 The slowing during the last 2 decades of the historic rise in death rates from coronary heart disease (CHD) is likely due to improvements in modifiable risk factors in the general population.2 More widespread adoption of a healthy diet and lifestyle has the potential to yield dramatic decreases in the incidence of CHD and its associated morbidity, mortality, and economic burden.3 A critical prerequisite for such an improvement is increased awareness of the health benefits of risk factor modification.
The American Heart Association (AHA) is a national nonprofit organization that provides public education and funding for scientific research on cardiovascular disease and stroke.4 Since 1998, the AHA has sponsored the "Cholesterol Low Down," a national program to enhance the understanding and control of CHD risk factors.5 To facilitate content development and the targeting of the program to the appropriate population, the AHA sponsored a national survey of adults' understanding of the relationship between cholesterol and other risk factors and CHD. We report the results of that survey to help focus the efforts of health care providers on the need to educate their patients and the general public about preventing CHD.
The AHA engaged a professional market survey company (Opinion Research Corp International, Princeton, NJ) to conduct a national telephone survey. Calls were placed between April 5 and April 9, 2001, based on random-digit dialing, with imposed regional quotas. Within each of the 4 geographic regions (northeast, north central, south, and west), another quota was imposed to ensure an even balance between male and female respondents. Calls were placed between 5 PM and 9 PM (respondent time) on weekdays, and from 11 AM to 9 PM on Saturdays and Sundays. All interviews were conducted in English by trained interviewers using a proprietary computerized system, and only 1 respondent was interviewed per household. Up to 5 attempts were made per telephone number to complete an interview. All respondents 18 years and older were asked demographic questions. Only respondents 40 years and older were asked questions about heart disease. Responses were then weighted to obtain a national probability sample matched to the 1999 census projections for region of the country, age, sex, and race.6
A total of 38 204 telephone numbers were generated for use, and 35 428 calls were placed. Of these calls, 25 896 (73.1%) were to either businesses or nonworking numbers, or were not answered. Of the remaining 9532 calls, a total of 4432 (46.5% of eligible calls, 12.5% of all calls) were answered but individuals declined to participate. An additional 806 calls (8.5% of eligible, 2.3% of total) were not completed because of language barriers, and 1150 (12.1% of eligible, 3.2% of total) either resulted in incomplete interviews or were not tabulated because they exceeded predefined regional and/or sex quotas. Interviews were completed in 2032 calls (21.3% of eligible, 5.7% of total). Of these, 1163 respondents were 40 years or older and completed the heart-related questions. Interviews averaged approximately 20 minutes in length. Finally, the responses from these 1163 interviews were weighted to create a national probability sample of 1114 respondents. The remaining reported results are all based on this sample of 1114.
The demographic profile of the respondents is shown in Table 1. Respondents were asked to identify which of the "health or lifestyle factors" that were read from a standard list pertained to them personally. This was the last of the health-related questions asked, so that the list offered did not contaminate responses to other questions (Figure 1). Despite the prevalence of these unfavorable characteristics, 71.0% (791) estimated their own risk of developing heart disease at average or below average, including 2.0% (22) who stated that they believed they were at no risk at all.
The first heart-related question asked was, "How important is it to you personally to have healthy cholesterol levels?" (Figure 2). Despite the apparent recognition of the importance of cholesterol, respondents were not well informed about the "desirable total cholesterol level for healthy adults." More respondents either did not know (42.3% ) or overestimated the desirable level (10.8% ) than were able to identify 200 mg/dL (5.17 mmol/L) as the correct value (Figure 3). Even among those who did not overestimate the target, 20.8% (234) stated that a desirable total cholesterol level for a healthy adult was less than 175 mg/dL (4.53 mmol/L), and 12.0% (134) said it was less than 150 mg/dL (3.88 mmol/L), suggesting that they too were not well informed about national guidelines.
Respondents were asked if they were aware of national guidelines indicating
"an acceptable level of cholesterol in healthy adults" (Figure 4). Most respondents were unaware of the existence of national guidelines for cholesterol management. Specific knowledge of their own cholesterol levels was also solicited (Figure 5). Despite their earlier answers regarding the importance of a healthy cholesterol level, most respondents did not know their own cholesterol level.
Several questions were meant to identify opportunities for learning more about cholesterol and heart disease. Interviewees were asked to report the sources of "information about cholesterol management" as an open-ended question (no suggested responses) and interviewers were instructed to record up to 3 answers per interview (Figure 6). Respondents identified physicians overwhelmingly (66.8%) as the source of information on which they relied most heavily. Only small numbers of respondents stated that they relied most on other sources, and only 3.7% (42) identified the Internet among their most important sources of information about cholesterol management. Respondents were asked when they had last discussed cholesterol management and their "personal cholesterol goal" with their "health care professional or doctor" (Figure 7). Most stated that they had had such a conversation within the past year.
We present a summary of a recent, comprehensive examination of the public awareness and understanding of cholesterol as a risk factor for CHD.
Reducing the risk of cardiovascular disease in individuals and populations requires changing behavior—inducing people to quit smoking, adopt diets low in saturated fats and cholesterol, exercise on a regular basis, and achieve and maintain a lean body weight. Knowledge of risk factors alone is insufficient to cause change in behavior.7 Nevertheless, knowledge about the link between lifestyle and disease is an essential prerequisite for any behavior-change process, and major, coordinated national efforts to educate the public about cholesterol and heart disease began in the 1980s.8 Several previous studies have documented the improvement in public risk factor awareness since these programs began.
Schucker et al9 reported on 2 surveys conducted by the National Heart, Lung, and Blood Institute and the Food and Drug Administration in 1983 and 1986. National telephone surveys documented an increase in the percentage of adults who believed that reducing high blood cholesterol levels would have a large effect on heart disease, from 64% in 1983 to 72% in 1986. They found a corresponding increase in the percentage of adults who had been screened for hypercholesterolemia, from 35% to 46%, and an increase from 14% to 23% in those who reported changes to their diet specifically made to lower cholesterol. The same group of investigators reported on a third national telephone survey conducted in 1990, which showed a further increase to 65% of the population who reported having been screened for elevated blood cholesterol level.10
Farquhar and colleagues11 reported on time trends in the knowledge, cholesterol levels, and lifestyle of adults in communities in California that were part of the Stanford Five-City Project. The Five-City Project demonstrated the favorable impact of community-wide education programs on the understanding of risk factors for CHD and their prevalence in the population. In a later report,12 the investigators reported on the findings in the control cities, where no specific programs were implemented, suggesting that these communities reflected national trends. They found improvements in specific knowledge about cholesterol, dietary behavior, and blood lipids between 1979 and 1990.
The Minnesota Heart Survey was a serially applied population-based survey limited to the Minneapolis– St Paul metropolitan area. Pieper et al13 found that a substantially greater percentage of respondents knew their own cholesterol level in 1990 to 1992 (54.9% of women, 46.5% of men) compared with 1980 to 1982 (15.4% of women and 18.5% of men). They also reported significant increases in the percentage of people reporting cholesterol screening as part of their routine medical evaluations.
The most recent national data on cholesterol screening and awareness come from the analysis of the Centers for Disease Control and Prevention Behavioral Risk Factor Surveillance System.14 In 1999, the estimated national cholesterol-screening rate for adults 20 years or older was 70.8%.15 Of those who reported they had undergone screening, the self-reported rate of high blood cholesterol level was 28.6%.6 Both of these rates were higher in 1999 than they had been in 1991.
Our findings extend these earlier reports in several important ways. First, the nationally representative nature of the respondents to our survey gives a broad picture of the state of public awareness and understanding throughout the United States. Second, our data are more contemporary. All of the previously cited reports document significant changes over time, reinforcing the need for current data on which to base interventions and public policy. Third, our questionnaire posed a broad range of questions about cholesterol and other risk factors, while other geographically broad surveys such as the Centers for Disease Control and Prevention Behavioral Risk Factor Surveillance System were sharply limited in scope.
Our study has limitations. While the profile of respondents matches the national and regional demographics for age, sex, and race, the methods used necessarily excluded non–English-speaking residents and individuals without telephones. This may have biased our sample toward more affluent and better-educated individuals, and previous investigators have reported differences in cholesterol awareness and knowledge based on these characteristics.12 All of the respondents were willing to take about 20 minutes to take a detailed telephone survey, and they may have been more health conscious or compliant than the general population. The low response rate limits the generalizability of the results. The phrase "cholesterol management," used in several questions, may have been unfamiliar to respondents and was not defined for them. Finally, data on other risk factors such as hypertension and smoking are self-reported.
The current data point out that, despite the progress in public education, much more remains to be done to achieve the potential public health benefits of adequate risk factor modification. The survey also provides valuable insight into avenues for making this progress. Respondents identified their physicians overwhelmingly as the source of cholesterol information on which they rely. Furthermore, most respondents reported that they had discussed cholesterol management with their physician or other health care provider within the past year.
The combination of frequent opportunities to deliver the message and the self-reported receptivity to receiving cholesterol information among patients means that physicians and other health care providers have a tremendous opportunity to improve their education of patients and lower the morbidity and mortality of atherosclerotic vascular disease.
Corresponding author: Ira S. Nash, MD, The Zena and Michael A. Wiener Cardiovascular Institute, Mount Sinai Medical Center, Box 1030, 1 Gustave L. Levy Pl, New York, NY 10029 (e-mail: firstname.lastname@example.org).
Accepted for publication September 20, 2002.
This study was supported by a grant from Pfizer Inc, New York, NY, to the American Heart Association.
This study was presented as an abstract at the 51st Annual Scientific Sessions of the American College of Cardiolog; March 19, 2002; Atlanta, Ga.
We thank the staff of Ketchum Inc, New York, NY, who helped compile the data.