Developmental Perspectives on Health Disparities from Conception Through Adulthood Risk Factors for Heart Disease Philip Greenland, MD Harry W. Dingman Professor Chair, Department of Preventive Medicine Feinberg School of Medicine
Outline n Risk factors for cardiovascular disease n Extent to which low-risk traits are protective n Extent to which low risk behaviors are protective n Social Class, CHD Risk, and CHD Risk Factors risk factors relate to social class and partially determine risk of CHD.
Age-adjusted CHD death rates per 10,000 person-years by level of serum cholesterol and SBP (Non-smokers) SBP Quintile, mmhg Rates Range From 3.1-33.7 142+ 132-141 125-131 118-124 <118 <182 182-202 203-220 221-244 Cholesterol Quintile, mg/dl 245+ Neaton J, et al. Arch Int Med 1992;152:56-64. (MRFIT Screenees)
Age-adjusted CHD rates per 10,000 personyears by level of serum cholesterol and SBP (Smokers) SBP Quintile, mm Hg Rates Range From 9.8-62.6 142+ 132-141 125-131 118-124 <118 <182 182-202 203-220 221-244 Cholesterol Quintile, mg/dl 245+ Neaton J, et al. Arch Int Med 1992;152:56-64. (Screenees in MRFIT)
Low risk-factor profile and long-term cardiovascular and noncardiovascular mortality and life expectancy: findings for 5 large cohorts of young adult and middleaged men and women Stamler J, Stamler R, Neaton JD, Wentworth D, Daviglus ML, Garside D, Dyer AR, Liu K, Greenland P. JAMA 1999 Dec 1; 282(21):2012-8
Studies of Low-Risk n SBP < 120 mm Hg n DBP < 80 mm Hg n No BP meds n Cholesterol < 200 mg/dl n Non-smoking n No diabetes and no prior MI n Low Risk people had all of the above approximately 7 percent of the cohorts
Low-Risk Traits: CHD Mortality in MRFIT and CHA Stamler, et al. JAMA, 1999 18-25 Years Follow-Up Cohort No. entire cohort Deaths (Rate) Low- Risk Deaths (Rate) All Others Age-Adjusted RR (95%CI) MRFIT men aged 35-39 y CHA men aged 18-39 y 72144 11 (0.2) 735 (1.5) 0.14 (0.08-0.25) 10025 1 (0.6) 126 (5.9) 0.08 (0.01-0.61) MRFIT men aged 40-57 y 270671 126 (4.4) 9578 (19.9) 0.22 (0.18-0.26) CHA men aged 40-59 y CHA women aged 40-59 y 7490 6 (8.8) 516 (38.1) 0.23 (0.10-0.51) 6229 2 (3.5) 181 (14.5) 0.21 (0.05-0.84)
Low-Risk Traits: All-Cause Mortality in MRFIT and CHA. 18-25 Years Follow-Up Stamler, et al. JAMA, 1999. Cohort No. Entire Cohort Deaths (Rate) Low-Risk Deaths (Rate) Others Age- Adjusted RR (95% CI), Low-Risk vs. Others Estimated Greater Life Expectancy, Low-Risk vs. Others, y MRFIT men aged 35-39 y 72144 139 (2.5) 2574 (5.2) 0.50 (0.42-0.59) 6.3 CHA men aged 18-39 y 10025 20 (10.2) 479 (23.5) 0.43 (0.28-0.68) 9.5 MRFIT men aged 40-57 y 270671 848 (29.2) 31034 (64.4) 0.45 (0.42-0.48) 5.9 CHA men aged 40-59 y 7490 36 (54.6) 1684 (124.9) 0.42 (0.30-0.58) 6.0 CHA women aged 40-59 y 6229 30 (36.1) 843 (68.4) 0.60 (0.42-0.87) 5.8
Low Risk Behaviors and CHD Risk in the Nurses Health Study, 1980 to 1994 Group Three low-risk factors Diet score in upper 2 quintiles; Nonsmoking; Moderate-to-vigorous exercise 30 min/day Four low-risk factors Diet, Nonsmoking, Exercise 30 min/day, BMI < 25 Five low-risk factors Diet, Nonsmoking, Exercise 30 min/day, BMI < 25, Alcohol 5 g/day % of Women In Group No. of CHD Events Relative Risk (95% CI) 12.7 62 0.43 (0.33-0.5 5) 7.2 24 0.34 (0.23-0.5 2) 3.1 5 0.17 (0.07-0.4 1) Population Attributable Risk (%) (95% CI) 54 (42-64) 64 (46-76) 82 (58-93)
May 16, 2005 Life at the Top in America Isn't Just Better, It's Longer By JANNY SCOTT Class is a potent force in health and longevity in the United States. The more education and income people have, the less likely they are to have and die of heart disease, strokes, diabetes and many types of cancer. Upper-middleclass Americans live longer and in better health than middleclass Americans, who live longer and better than those at the bottom. And the gaps are widening, say people who have researched social factors in health.
May 16, 2005 Life at the Top in America Isn't Just Better, It's Longer By JANNY SCOTT As advances in medicine and disease prevention have increased life expectancy in the United States, the benefits have disproportionately gone to people with education, money, good jobs and connections. They are almost invariably in the best position to learn new information early, modify their behavior, take advantage of the latest treatments and have the cost covered by insurance.
May 16, 2005 Life at the Top in America Isn't Just Better, It's Longer By JANNY SCOTT Many risk factors for chronic diseases are now more common among the less educated than the better educated. Smoking has dropped sharply among the better educated, but not among the less. Physical inactivity is more than twice as common among high school dropouts as among college graduates. Lower-income women are more likely than other women to be overweight, though the pattern among men may be the opposite.
May 16, 2005 Life at the Top in America Isn't Just Better, It's Longer By JANNY SCOTT Heart attack is a window on the effects of class on health. The risk factors - smoking, poor diet, inactivity, obesity, hypertension, high cholesterol and stress - are all more common among the less educated and less affluent, the same group that research has shown is less likely to receive cardiopulmonary resuscitation, to get emergency room care or to adhere to lifestyle changes after heart attacks.
Explanations for the social gradient in CHD risk The extent to which social class differences can be explained by established coronary risk factors has been assessed in a number of studies. In this study, when considered together, the adult coronary risk factors explained 39% of the CHD difference between social classes, less than the sum of the individual contributions due to the multifactorial nature of CHD. A 25-year follow-up of men in the Whitehall study found that cigarette smoking, blood pressure, total cholesterol, and glucose together accounted for 56% of the CHD risk difference between low-risk men in the lowest and highest grades of employment. Our observation that height is the second most important determinant of the social class gradient in CHD suggests that early life factors may be important in the development of social differences in CHD an observation consistent both with the relationship between height and CHD in individuals and with recent evidence that childhood socioeconomic environment may be directly related to the risk of CHD.
Implications for CHD prevention Though reducing the CHD risk of all subjects in manual occupations to the level of non-manual subjects would have an appreciable effect (approximately one-fifth of CHD events during middle-age would be prevented), it would be modest compared with the expected reductions following population-wide reductions in mean total cholesterol and blood pressure, where it is estimated that 57% of major CHD cases during middle age would be prevented if long term mean population levels of total cholesterol and blood pressure could be reduced by 15% (JR Emberson unpublished data). Indeed, it has been suggested that the CHD epidemic could effectively be ended if the proportion of the population at lifetime low exposure levels of total cholesterol, blood pressure, and cigarette smoking could be substantially increased.
Circulation. 1982 Dec; 66(6):1308-14 Relationship of education to major risk factors and death from coronary heart disease, cardiovascular diseases and all causes. Findings of three Chicago epidemiologic studies Liu K, Cedres LB, Stamler J, Dyer A, Stamler R, Nanas S, Berkson DM, Paul O, Lepper M, Lindberg HA, Marquardt J, Stevens E, Schoenberger JA, Shekelle RB, Collette P, Shekelle S, Garside D.
J Hum Hypertens. 2003 Sep; 17(9):655-775 Higher blood pressure in middleaged American adults with less education-role of multiple dietary factors: the INTERMAP study Stamler J, et al Extensive evidence exists that an inverse relation between education and blood pressure prevails in many adult populations, but little research has been carried out on reasons for this finding With participants stratified by years of education, and assessment of 100+ dietary variables from four 24- h dietary recalls and two 24-h urine collections/person, graded relationships were found between education and intake of many macro- and micronutrients, electrolytes, fibre, and body mass index (BMI). BMI markedly reduced size of education-bp relations, more so for women than for men
J Hum Hypertens. 2003 Sep;17(9):655-775 Higher blood pressure in middleaged American adults with less education-role of multiple dietary factors: the INTERMAP study Stamler J, et al Combinations of these dietary variables and BMI attenuated the education-sbp inverse coefficient by 54-58%, and the education-dbp inverse coefficient by 59-67%, with over half these effects attributable to specific nutrients (independent of BMI). As a result, the inverse education-bp coefficients ceased to be statistically significant. Multiple specific dietary factors together with body mass largely account for the more adverse BP levels of less educated than more educated Americans. Special efforts to improve eating patterns of less educated strata can contribute importantly to overcoming this and related health disparities in the population.
Am J Public Health. 1996 Apr; 86(4):497-504 Socioeconomic differentials in mortality risk among men screened for the Multiple Risk Factor Intervention Trial: II. Black men. Smith GD, Wentworth D, Neaton JD, Stamler R, Stamler J. This study examined socioeconomic differentials in risk of death from a number of causes in a large cohort of Black men in the United States. For 20,224 Black men screened for the Multiple Risk Factor Intervention Trial between 1973 and 1975, data were collected on median family income of Black households in zip code of residence, age, cigarette smoking, blood pressure, serum cholesterol, previous heart attack, and drug treatment for diabetes. 2937 deaths occurred over the 16-year follow-up period and were grouped into specific causes and related to median Black family income.
Am J Public Health. 1996 Apr; 86(4):497-504 Socioeconomic differentials in mortality risk among men screened for the Multiple Risk Factor Intervention Trial: II. Black men. Smith GD, Wentworth D, Neaton JD, Stamler R, Stamler J. There was an inverse association between age-adjusted all-cause mortality and median family income. There was no attenuation of this association over the follow-up period, and the association was similar for the 22 clinical centers carrying out the screening. The gradient was seen for most of the specific causes of death, although the strength of the association varied. Median income was markedly lower for the Black men screened than for the White men, but the relationship between income and all-cause mortality was similar.
Concluding Remarks n Major CHD Risk Factors are well established, occur commonly in diseased populations, and are more prevalent in lower social and economic strata of Western countries. n A portion of CHD risk is accounted for by social and economic disparities, some of which exceeds that due to more adverse CHD risk profiles.