Abstract 2354: Multilevel analysis of colorectal cancer screening in southeastern Pennsylvania

Background: Colorectal cancer (CRC) is a leading cause of mortality in the US. There are racial and socioeconomic disparities in CRC incidence and mortality, in part due to underuse of CRC screening. The goal of this cross-sectional study was to examine multilevel factors associated with CRC screening in Southeastern PA.

Methods: We conducted a cross-sectional study using the Public Health Management Corporation's Community Health Database household survey (2010-2015) and American Community Survey data (2010-2014) to examine multilevel factors related to CRC screening via sigmoidoscopy and colonoscopy. We compared adults age 50+ that received CRC screening within 10 years (N=12963) to non-compliant individuals (N=4585), according to American Cancer Society guidelines. We conducted descriptive analyses to compare individual and residential census tract characteristics of the compliant and non-compliant groups. Multilevel regression models including random intercepts for census tracts (CTs) and CT-level socioeconomic status (SES) were used to examine independent associations with CRC screening compliance. P-values <0.05 were considered statistically significant.

Results: In bivariate analysis, we observed that individuals that did not comply with CRC screening recommendations were more likely to be younger, male, non-black, unmarried, less educated, uninsured, and current smokers than those in compliance. Non-compliant individuals were also more likely to live in areas with lower SES, shorter distance to public transportation, lower educational attainment, lower median income, and higher percentages of uninsured, unemployed, poverty and households on public assistance compared to those in compliance. In multilevel regression analysis, being unmarried (OR=1.49, 95% CI=1.34-1.65), uninsured (OR=1.65, 95% CI=1.30-2.10), or living in lower SES census tracts (below the first SES quartile: OR=1.48, 95% CI=1.30-1.69 and between the 2nd and 3rd quartile: OR=1.51, 95% CI=1.29-1.75 vs. above the highest quartile) were associated with non-compliance in CRC screening recommendations. There were no interactions detected between race and census tract SES in these models.

Conclusions: We identified multilevel factors (marital status, health insurance status, and residential SES) significantly associated with non-compliance to CRC screening recommendations. Individuals and CTs with low levels of compliance can be identified and targeted for tailored interventions, such as peer support and community education about CRC in future studies. Future studies might examine how the availability and location of screening facilities may relate to CRC screening recommendation compliance rates in different neighborhoods.

Citation Format: Charnita M. Zeigler-Johnson, Scott Keith, Kari Moore, Russell McIntire, Preethi Selvan, Steven Melly, Ana Diez-Roux. Multilevel analysis of colorectal cancer screening in southeastern Pennsylvania [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 2354.

Spatial accessibility to pediatric primary care in Philadelphia: an area-level cross sectional analysis

Background

Pediatric primary care visits are a foundational element in the health maintenance of children. Differential access may be a driver of racial inequities in health. We hypothesized that pediatric primary care accessibility would be lowest in neighborhoods with higher proportion of non-Hispanic Black residents.

Methods

Annual ratios (2008–2016) of providers to pediatric population were calculated by census tract in Philadelphia, Pennsylvania. Marginal logistic regression was used to estimate the independent association between neighborhood racial composition and access to pediatric primary care controlling for confounders.

Results

In general, low access to care was associated with greater neighborhood disadvantage (e.g., SES, % poverty, % public insurance). After controlling for neighborhood indicators of disadvantage, risk of being in the lowest quintile of access significantly increased as the percent of non-Hispanic Black residents increased.

Conclusion

A new measure of pediatric primary care accessibility demonstrates a persistent disparity in primary care access for predominantly non-Hispanic Black neighborhoods.

Association of psychosocial factors with leukocyte telomere length among African Americans in the Jackson Heart Study

Leukocyte telomere length (LTL) is a biomarker of cellular aging. African Americans report more stress than other groups; however, the association of psychosocial stressors with biological aging among African Americans remains unclear. The current study evaluated the association of psychosocial factors (negative affect and stressors) with LTL in a large sample of African American men and women (n = 2,516) from the Jackson Heart Study. Using multivariable linear regression, we examined the sex-specific associations of psychosocial factors (cynical distrust, anger in and out, depressive symptoms, negative affect summary scores, global stress, weekly stress, major life events, and stress summary scores) with LTL. Model 1 adjusted for demographics and education. Model 2 adjusted for model 1, smoking, alcohol intake, physical activity, diabetes, hypertension, and high-sensitivity C-reactive protein. Among women, high (vs. low) cynical distrust was associated with shorter mean LTL in model 1 (b = -0.12; p = 0.039). Additionally, high (vs. low) anger out and expressed negative affect summary scores were associated with shorter LTL among women after full adjustment (b = -0.13; p = 0.011; b = -0.12, p = 0.031, respectively). High levels of cynical distrust, anger out, and negative affect summary scores may be risk factors for shorter LTL, particularly among African-American women.

FPCA-based method to select optimal sampling schedules that capture between-subject variability in longitudinal studies

A critical component of longitudinal study design involves determining the sampling schedule. Criteria for optimal design often focus on accurate estimation of the mean profile, although capturing the between-subject variance of the longitudinal process is also important since variance patterns may be associated with covariates of interest or predict future outcomes. Existing design approaches have limited applicability when one wishes to optimize sampling schedules to capture between-individual variability. We propose an approach to derive optimal sampling schedules based on functional principal component analysis (FPCA), which separately characterizes the mean and the variability of longitudinal profiles and leads to a parsimonious representation of the temporal pattern of the variability. Simulation studies show that the new design approach performs equally well compared to an existing approach based on parametric mixed model (PMM) when a PMM is adequate for the data, and outperforms the PMM-based approach otherwise. We use the methods to design studies aiming to characterize daily salivary cortisol profiles and identify the optimal days within the menstrual cycle when urinary progesterone should be measured.

Association between perceived neighbourhood characteristics, physical activity and diet quality: results of the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil)

BACKGROUND

The study explores associations between perceived neighbourhood characteristics, physical activity and diet quality, which in Latin America and Brazil have been scarcely studied and with inconsistent results.

METHODS

We conducted a cross-sectional analysis of 14,749 individuals who participated in the Brazilian Longitudinal Study of Adult Health (Estudo Longitudinal de Saúde do Adulto, ELSA-Brasil) baseline. The study included current and retired civil servants, aged between 35 and 74 years, from universities and research institutes in six Brazilian states. The International Physical Activity Questionnaire (IPAQ) long form was used to characterize physical activity during leisure time and commuting; additional questions assessed how often fruit and vegetables were consumed, as a proxy for diet quality. Neighbourhood characteristics were evaluated by the "Walking Environment" and "Availability of Healthy Foods" scales originally used in the Multi-Ethnic Study of Atherosclerosis (MESA). Associations were examined using multinomial logistic regression.

RESULTS

Perceiving a more walkable neighbourhood was positively associated with engaging in leisure time physical activity and doing so for longer weekly. Compared with those who saw their neighbourhood as less walkable, those who perceived it as more walkable had 1.69 (95 % CI 1.57-1.83) and 1.39 (1.28-1.52) greater odds of engaging in leisure time physical activity for more than 150 min/week or up to 150 min/week (vs. none), respectively. Perceiving a more walkable neighbourhood was also positively associated with transport-related physical activity. The same pattern was observed for diet: compared with participants who perceived healthy foods as less available in their neighbourhood, those who saw them as more available had odds 1.48 greater (1.31-1.66) of eating fruits, and 1.47 greater (1.30-1.66) of eating vegetables, more than once per day.

CONCLUSIONS

Perceived walkability and neighbourhood availability of healthy food were independently associated with the practice of physical activity and diet quality, respectively, underlining the importance of neighbourhood-level public policies to changing and maintaining health-related habits.

Abstract 214: Is Goal-Striving Stress Associated With Cardiovascular Disease Among Jackson Heart Study Participants?

Introduction: It is known that psychosocial stress is associated with cardiovascular disease (CVD). Recent research has reported that goal-striving stress (GSS) is associated with poor health outcomes for African Americans. GSS is the “¼discrepancy between aspiration and achievement, and the level of disappointment experienced if goals are not reached.” As far as we know, no research has examined the relationship between GSS and CVD prevalence among African Americans. Thus, the purpose of the current study was to investigate the association between GSS and CVD prevalence among a large sample of African Americans.

Methods: The Jackson Heart Study (JHS) includes 5,181 men (37%) and women who completed a baseline survey to capture data on psychosocial variables, CVD history, demographic variables, and CVD risk factors. It was hypothesized that higher levels of GSS would be associated with CVD prevalence. The average GSS level was 4.49. GSS was categorized into tertiles with CVD prevalence and associations assessed cross-sectionally by multivariable logistic regression analysis that adjusted for demographic, behavioral and clinical risk factors.

Results: It was found that GSS was significantly associated with CVD for tertiles 1, 2, and 3 at 41.26%, 36.25%, and 22.49% respectively. Additionally, GSS was significantly associated with CVD prevalence per unit increase after adjusting for age and sex (OR 1.03, 95% CI 1.02-1.05), SES (OR 1.03, 95% CI 1.02-1.05), and smoking, diet, physical activity, and sleep (OR 1.03, 95% CI 1.01-1.05). However, there was slight attenuation after adjustment for CVD risk factors (OR 1.01, 95% CI 0.99-1.04).

Conclusions: The present study represents an important contribution to the literature in that it appears to be the first to empirically investigate the link between GSS and CVD prevalence among African American men and women.

Examining the impact of the walking school bus with an agent-based model

We used an agent-based model to examine the impact of the walking school bus (WSB) on children's active travel to school. We identified a synergistic effect of the WSB with other intervention components such as an educational campaign designed to improve attitudes toward active travel to school. Results suggest that to maximize active travel to school, children should arrive on time at "bus stops" to allow faster WSB walking speeds. We also illustrate how an agent-based model can be used to identify the location of routes maximizing the effects of the WSB on active travel. Agent-based models can be used to examine plausible effects of the WSB on active travel to school under various conditions and to identify ways of implementing the WSB that maximize its effectiveness.

Association of health professional shortage areas and cardiovascular risk factor prevalence, awareness, and control in the Multi-Ethnic Study of Atherosclerosis (MESA)

BACKGROUND- Individuals living in primary care health professional shortage areas (PC-HPSA), often have difficulty obtaining medical care; however, no previous studies have examined association of pc-hpsa residence with prevalence of cardiovascular disease risk factors. METHODS AND RESULTS- To examine this question, the authors used data from the Multi-Ethnic Study of Atherosclerosis baseline examination (2000-2002). Outcomes included the prevalence of diabetes, hypertension, hyperlipidemia, smoking, and obesity as well as the awareness and control of diabetes, hypertension, and hyperlipidemia. Multivariable Poisson models were used to examine the independent association of PC-HPSA residence with each outcome. Models were sequentially adjusted for demographics, acculturation, socioeconomic status, access to health care, and neighborhood socioeconomic status. Similar to the national average, 16.7% of Multi-Ethnic Study of Atherosclerosis participants lived in a PC-HPSA. In unadjusted analyses, prevalence rates of diabetes (14.8% versus 11.0%), hypertension (48.2% versus 43.1%), obesity (35.7% versus 31.1%), and smoking (15.5% versus 12.1%) were significantly higher among residents of PC-HPSAs. There were no significant differences in the awareness or control of diabetes, hypertension, or hyperlipidemia. After adjustment, residence in a PC-HPSA was not independently associated with cardiovascular disease risk factor prevalence, awareness, or control. CONCLUSIONS- This study suggests that increased prevalence of cardiovascular disease risk factors in PC-HPSAs are explained by the demographic and socioeconomic characteristics of their residents. Future interventions aimed at increasing the number of primary care physicians may not improve cardiovascular risk without first addressing other factors underlying health care disparities.

Associations of acculturation and kidney dysfunction among Hispanics and Chinese from the Multi-Ethnic Study of Atherosclerosis (MESA)

BACKGROUND

Acculturation affects health, but it has never been studied with kidney disease.

METHODS

We studied the association of language spoken at home, generation and birth place with kidney function among Hispanics and Chinese in the Multi-Ethnic Study of Atherosclerosis (n = 2999). Kidney function was determined by cystatin C (eGFRcys) and albumin/creatinine ratio (ACR). We evaluated mediators in models: Model 1 = age, sex, income, education; Model 2 = Model 1 + behaviors; and Model 3 = Model 1 + comorbidities.

RESULTS

Among Hispanics, speaking mixed Spanish/English was significantly associated with lower eGFRcys (- 2.83 mL/min/1.73 m(2), - 5.69-0.04) and higher ACR (RD 40%, 17-68%) compared with speaking Spanish only; this was mildly attenuated by behaviors (- 2.29, - 5.33-0.75; RD 42%, 18-72%) but not comorbidities (- 3.04, - 5.83 to - 0.23); RD 35%, 14-59%). US-born Hispanics had lower eGFRcys compared with foreign-born Hispanics [1.83 mL/min/1.73 m(2) lower (0.97-1.31) for Generation 1; 1.37 mL/min/1.73 m(2) lower (0.75-1.57) for Generation ≥ 2]. In contrast, Chinese who spoke any English had higher eGFRcys (2.53, 95% CI: - 1.70-6.78), but similar ACR (RD - 5%, 95% CI: - 26-23%) compared with those speaking Chinese only, but associations were not statistically significant.

CONCLUSION

Higher acculturation was associated with worse kidney function in Hispanics, mediated perhaps by behavioral factors but not comorbidities. Associations may be in the opposite direction among Chinese. Future studies are needed to elucidate these mechanisms.

Psychosocial risk factors and retinal microvascular signs: the multi-ethnic study of atherosclerosis

The association between psychosocial risk factors and retinal microvascular signs was examined in the Multi-Ethnic Study of Atherosclerosis. Subjects were recruited from Baltimore, Maryland; Chicago, Illinois; Forsyth County, North Carolina; Los Angeles County, California; New York, New York; and St. Paul, Minnesota. Levels of depressive symptoms, trait anger, trait anxiety, chronic burdens, emotional support, and cynical distrust were assessed by questionnaire (from July 2000 to July 2002). Digital retinal images (from August 2002 to January 2004) from 6,147 participants were used to evaluate retinopathy and retinal vascular caliber. After controlling for potential confounding factors, the authors found that subjects without access to emotional support (Enriched Social Support Instrument score of <19 vs. > or = 19) had 60% greater odds of retinopathy (odds ratio = 1.6, 95% confidence interval (CI): 1.3, 2.0). Subjects with high Spielberger trait-anxiety scale scores (> or = 22 vs. < or = 14) and subjects with high depressive symptoms (Center for Epidemiology Studies Depression Scale score, > or = 16 vs. <16) were also more likely to have retinopathy (odds ratio = 1.4, 95% CI: 1.1, 1.9 and odds ratio = 1.5, 95% CI: 1.2, 1.9), respectively. In this cross-sectional study, lack of emotional support, increased trait anxiety, and more depressive symptoms were associated with retinopathy signs, independently of other known risk factors.

Socioeconomic and psychosocial gradients in cardiovascular pathogen burden and immune response: the multi-ethnic study of atherosclerosis

BACKGROUND

The biologic mechanisms linking socioeconomic position and psychosocial factors to cardiovascular disease (CVD) are not well understood. Immune response to persistent pathogens may be one of these mechanisms.

METHODS

We analyzed cross-sectional data from the multi-ethnic study of atherosclerosis (N=999) composed of adults age 45-84. Log-binomial regression and ordinal logistic regression models were used to examine associations of socioeconomic factors and psychosocial factors with pathogen burden and immune response among those infected. Pathogen burden was assessed based on seroprevalence of Helicobacter pylori, cytomegalovirus, herpes simplex virus-1, and Chlamydia pneumoniae and antibody levels were used to characterize high immune response to all four pathogens.

RESULTS

Low education was a strong and significant independent predictor of higher pathogen burden after adjustment for covariates (adjusted odds ratio (OR) 95% confidence interval (CI) 1.37, 1.19-1.57). Among subjects seropositive for all four pathogens, low education and a higher level of chronic psychosocial stress showed a positive association with higher antibody response, although associations were no longer significant in models with all covariates included (OR=1.64, 95% CI 0.82-3.31 for lowest vs. highest educational category and OR=1.29, 95% CI 0.96-1.73 for a one level increase in chronic stress).

CONCLUSION

Pathogen burden and heightened immune response may represent a biological pathway by which low socioeconomic position and chronic stress are related to increased rates of cardiovascular disease.

Dietary patterns, food groups, and telomere length in the Multi-Ethnic Study of Atherosclerosis (MESA)

BACKGROUND

Telomere length reflects biological aging and may be influenced by environmental factors, including those that affect inflammatory processes.

OBJECTIVE

With data from 840 white, black, and Hispanic adults from the Multi-Ethnic Study of Atherosclerosis, we studied cross-sectional associations between telomere length and dietary patterns and foods and beverages that were associated with markers of inflammation.

DESIGN

Leukocyte telomere length was measured by quantitative polymerase chain reaction. Length was calculated as the amount of telomeric DNA (T) divided by the amount of a single-copy control DNA (S) (T/S ratio). Intake of whole grains, fruit and vegetables, low-fat dairy, nuts or seeds, nonfried fish, coffee, refined grains, fried foods, red meat, processed meat, and sugar-sweetened soda were computed with responses to a 120-item food-frequency questionnaire completed at baseline. Scores on 2 previously defined empirical dietary patterns were also computed for each participant.

RESULTS

After adjustment for age, other demographics, lifestyle factors, and intakes of other foods or beverages, only processed meat intake was associated with telomere length. For every 1 serving/d greater intake of processed meat, the T/S ratio was 0.07 smaller (beta +/- SE: -0.07 +/- 0.03, P = 0.006). Categorical analysis showed that participants consuming >or=1 serving of processed meat each week had 0.017 smaller T/S ratios than did nonconsumers. Other foods or beverages and the 2 dietary patterns were not associated with telomere length.

CONCLUSIONS

Processed meat intake showed an expected inverse association with telomere length, but other diet features did not show their expected associations.

A case-control study of microenvironmental risk factors for urban visceral leishmaniasis in a large city in Brazil, 1999-2000

OBJECTIVES

We investigated potential microenvironmental risk factors for visceral leishmaniasis in urban and suburban areas, and developed risk scores to characterize the household and the neighborhood. These scores may be useful to identify microenvironments within cities that place residents at greater risk of visceral leishmaniasis.

METHODS

In this case-control study, cases were all persons with visceral leishmaniasis reported from July 1999 through December 2000 in the Belo Horizonte metropolitan area, Brazil. Two kinds of controls-neighborhood and hospital-were used. Cases and controls were matched by age (+/-2 years). We developed four scores to characterize the microenvironment (indoor, outdoor, animal indoor, and animal outdoor), and also considered the level of urbanization of the area.

RESULTS

A total of 106 neighborhood controls and 60 hospital controls were identified for 109 cases. Among the cases, 69 (63.3%) were men and 40 (36.7%) were women. Most cases were under 15 years old (64.2%), and 39 (35.8%) were 15 years old or more. The outdoor score [odds ratio (OR) = 1.49; 95% confidence interval (CI) = 1.03-2.14] and animal outdoor scores (OR = 1.79[95% CI 1.21-2.65]) were significantly associated with the odds of visceral leishmaniasis in our sample. We also found a significant interaction between sex and age. Compared to females 15 years old or more, males 15 years old or more were more likely to have visceral leishmaniasis (OR = 7.02[95% CI 2.20-22.20]).

CONCLUSIONS

Animals in the neighborhood were associated with a greater odds of visceral leishmaniasis. Cases were more likely than controls to live in transitional or rural areas, although this difference was not statistically significant, possibly because of the small sample size.

Racial/ethnic differences in hypertension and hypertension treatment and control in the multi-ethnic study of atherosclerosis (MESA)

BACKGROUND

Most previous studies investigating the association between ethnicity and hypertension focused on differences between African Americans and whites and did not include other racial/ethnic groups such as Chinese or Hispanics.

METHODS

We used data from the Multi-Ethnic Study of Atherosclerosis (MESA), a population-based study of 6814 adults without clinical cardiovascular disease, to examine the association between ethnicity and hypertension and hypertension treatment among white, African American, Chinese, and Hispanic ethnic groups.

RESULTS

The prevalence of hypertension, defined as systolic blood pressure (BP) <140 mm Hg and diastolic BP <90 mm Hg or self-reported treatment for hypertension, was significantly higher in African Americans compared to whites (60% v 38%; P < .0001), whereas prevalence in Hispanic (42%) and Chinese participants (39%) did not differ significantly from that in whites. After adjustment for age, body mass index, prevalence of diabetes mellitus, and smoking, African American (odds ratio [OR] 2.21; 95% confidence interval [95% CI] 1.91-2.56) and Chinese (OR 1.30; 95% CI 1.07-1.56) ethnicity were significantly associated with hypertension compared to whites. Among hypertensive MESA participants, the percentage of treated but uncontrolled hypertension in whites (24%) was significantly lower than in African Americans (35%, P < .0001), Chinese (33%, P = .003), and Hispanics (32%, P = .0005), but only African-American race/ethnicity remained significantly associated with treated but uncontrolled hypertension after controlling for socioeconomic factors (OR 1.35; 95% CI 1.07-1.71). Diuretic use was lowest in the Chinese (22%) and Hispanic participants (32%) and was significantly lower in these groups compared with white participants (47%; P < .0001 for both comparisons).

CONCLUSIONS

Programs to improve hypertension treatment and control should focus on a better understanding of differences in the prevalence of hypertension and hypertension control among minority groups in the United States, especially African Americans, compared with whites, and on techniques to prevent hypertension and improve control in high-risk groups.

"Fundamental causes" of social inequalities in mortality: a test of the theory

Medicine and epidemiology currently dominate the study of the strong association between socioeconomic status and mortality. Socioeconomic status typically is viewed as a causally irrelevant "confounding variable" or as a less critical variable marking only the beginning of a causal chain in which intervening risk factors are given prominence. Yet the association between socioeconomic status and mortality has persisted despite radical changes in the diseases and risk factors that are presumed to explain it. This suggests that the effect of socioeconomic status on mortality essentially cannot be understood by reductive explanations that focus on current mechanisms. Accordingly, Link and Phelan (1995) proposed that socioeconomic status is a "fundamental cause" of mortality disparities-that socioeconomic disparities endure despite changing mechanisms because socioeconomic status embodies an array of resources, such as money, knowledge, prestige, power, and beneficial social connections, that protect health no matter what mechanisms are relevant at any given time. We identified a situation in which resources should be less helpful in prolonging life, and derived the following prediction from the theory: For less preventable causes of death (for which we know little about prevention or treatment), socioeconomic status will be less strongly associated with mortality than for more preventable causes. We tested this hypothesis with the National Longitudinal Mortality Study, which followed Current Population Survey respondents (N = 370,930) for mortality for nine years. Our hypothesis was supported, lending support to the theory of fundamental causes and more generally to the importance of a sociological approach to the study of socioeconomic disparities in mortality.

Association of educational achievement with pulsatile arterial diameter change of the common carotid artery: the Atherosclerosis Risk in Communities (ARIC) Study, 1987-1992

Education is strongly inversely associated with common carotid artery intima-media thickness in the Atherosclerosis Risk in Communities (ARIC) Study. The authors extended the ARIC study of preclinical atherosclerosis by evaluating the cross-sectional association of education with common carotid artery elasticity. This study included 10,091 Black and White men and women aged 45-64 years who were free of clinical coronary heart disease and stroke/transient ischemic attack. Arterial elasticity was assessed by pulsatile arterial diameter change (PADC), derived from phase-locked echo-tracking. The smaller the PADC, the stiffer the artery. Education was categorized into grade school, high school without graduation, high school with graduation, vocational school, some college, and graduate/professional school. PADC was directly associated with educational attainment. The mean PADCs, adjusted for age, height, diastolic diameter, systolic blood pressure, pulse pressure (linear and squared), ethnicity, gender, and smoking status, in successively higher education strata were 402 (standard error (SE) 5), 403 (SE 4), 407 (SE 3), 413 (SE 4), 416 (SE 2), and 417 (SE 4) microm (p = 0.007). To the authors' knowledge, this is the first time such an association has been reported. If arterial dilation impairment precedes arterial wall thickening in the atherosclerotic process, as recent studies on endothelial dysfunction suggest, these results indicate that low socioeconomic status may be associated with early arterial pathophysiologic changes-an effect that appears to be mediated by established cardiovascular disease risk factors.

Short- and long-term prediction of clinical and subclinical atherosclerosis by traditional risk factors

This study compares the cross-sectional and longitudinal associations of cardiovascular risk factors with clinical coronary heart disease (CHD) and with subclinical carotid atherosclerosis measured by ultrasound. The study population were 1410 participants in the Atherosclerotic Risk in Community (ARIC) Study (1987-1989) who also participated in a 1974 community health survey. Smoking in 1974 was associated with increased CHD prevalence in 1987-1989 (adjusted prevalence ratio = 2.2), whereas the corresponding cross-sectional association was practically absent. For hypercholesterolemia and hypertension, the longitudinal associations with CHD were also stronger than the cross-sectional associations. In contrast, the strength of the longitudinal and cross-sectional associations with carotid atherosclerosis was generally similar. These results underscore the advantages of using subclinical measures of atherosclerosis in cross-sectional studies. In addition, they suggest that the presence of smoking, hypertension, or hypercholesterolemia in mid-adulthood may have some persisting effects on the development of atherosclerotic disease in later life.

Cigarette smoking and progression of atherosclerosis: The Atherosclerosis Risk in Communities (ARIC) Study

CONTEXT

Cigarette smoking is a powerful risk factor for incident heart disease and stroke, but the relationship of active and passive smoking with the progression of atherosclerosis has not been described.

OBJECTIVE

To examine the impact of active smoking and exposure to environmental tobacco smoke (ETS) on the progression of atherosclerosis.

DESIGN

A longitudinal assessment of the relationship between smoking exposure evaluated at the initial visit and the 3-year change in atherosclerosis.

SETTING

A population-based cohort of middle-aged adults from 4 communities in the United States.

PARTICIPANTS

A total of 10914 participants from the Atherosclerosis Risk in Communities (ARIC) study enrolled between 1987 and 1989.

MAIN OUTCOME MEASURE

Change in atherosclerosis from baseline to the 3-year follow-up as indexed by intimal-medial thickness of the carotid artery assessed by ultrasound and adjusted for demographic characteristics, cardiovascular risk factors, and lifestyle variables.

RESULTS

Exposure to cigarette smoke was associated with progression of atherosclerosis. Relative to never smokers and after adjustment for demographic characteristics, cardiovascular risk factors, and lifestyle variables, current cigarette smoking was associated with a 50% increase in the progression of atherosclerosis (mean progression rate over 3 years, 43.0 microm for current and 28.7 microm for never smokers, regardless of ETS exposure), and past smoking was associated with a 25% increase (mean progression rate over 3 years, 35.8 microm for past smokers and 28.7 microm for never smokers). Relative to those not exposed to ETS, exposure to ETS was associated with a 20% increase (35.2 microm for those exposed to ETS vs 29.3 microm for those not exposed). The impact of smoking on atherosclerosis progression was greater for subjects with diabetes and hypertension. Although more pack-years of exposure was independently associated with faster progression (P<.001), after controlling for the number of pack-years, the progression rates of current and past smokers did not differ (P=.11).

CONCLUSIONS

Both active smoking and ETS exposure are associated with the progression of an index of atherosclerosis. Smoking is of particular concern for patients with diabetes and hypertension. The fact that pack-years of smoking but not current vs past smoking was associated with progression of atherosclerosis suggests that some adverse effects of smoking may be cumulative and irreversible.