Steven Shea

Coronary calcium as a predictor of coronary events in four racial or ethnic groups.

BACKGROUND In white populations, computed tomographic measurements of coronary-artery calcium predict coronary heart disease independently of traditional coronary risk factors. However, it is not known whether coronary-artery calcium predicts coronary heart disease in other racial or ethnic groups. METHODS We collected data on risk factors and performed scanning for coronary calcium in a population-based sample of 6722 men and women, of whom 38.6% were white, 27.6% were black, 21.9% were Hispanic, and 11.9% were Chinese. The study subjects had no clinical cardiovascular disease at entry and were followed for a median of 3.8 years. RESULTS There were 162 coronary events, of which 89 were major events (myocardial infarction or death from coronary heart disease). In comparison with participants with no coronary calcium, the adjusted risk of a coronary event was increased by a factor of 7.73 among participants with coronary calcium scores between 101 and 300 and by a factor of 9.67 among participants with scores above 300 (P<0.001 for both comparisons). Among the four racial and ethnic groups, a doubling of the calcium score increased the risk of a major coronary event by 15 to 35% and the risk of any coronary event by 18 to 39%. The areas under the receiver-operating-characteristic curves for the prediction of both major coronary events and any coronary event were higher when the calcium score was added to the standard risk factors. CONCLUSIONS The coronary calcium score is a strong predictor of incident coronary heart disease and provides predictive information beyond that provided by standard risk factors in four major racial and ethnic groups in the United States. No major differences among racial and ethnic groups in the predictive value of calcium scores were detected.

Coronary artery calcification compared with carotid intima-media thickness in the prediction of cardiovascular disease incidence: the Multi-Ethnic Study of Atherosclerosis (MESA).

BACKGROUND Coronary artery calcium (CAC) and carotid intima-media thickness (IMT) are noninvasive measures of atherosclerosis that consensus panels have recommended as possible additions to risk factor assessment for predicting the probability of cardiovascular disease (CVD) occurrence. Our objective was to assess whether maximum carotid IMT or CAC (Agatston score) is the better predictor of incident CVD. METHODS A prospective cohort study of subjects aged 45 to 84 years in 4 ethnic groups, who were initially free of CVD (n = 6698) was performed, with standardized carotid IMT and CAC measures at baseline, in 6 field centers of the Multi-Ethnic Study of Atherosclerosis (MESA). The main outcome measure was the risk of incident CVD events (coronary heart disease, stroke, and fatal CVD) over a maximum of 5.3 years of follow-up. RESULTS There were 222 CVD events during follow-up. Coronary artery calcium was associated more strongly than carotid IMT with the risk of incident CVD. After adjustment for each other (CAC score and IMT) and age, race, and sex [corrected], the hazard ratio of CVD increased 2.1-fold (95% confidence interval [CI], 1.8-2.5) for each 1-standard deviation (SD) increment of log-transformed CAC score, vs 1.3-fold (95% CI, 1.1-1.4) for each 1-SD increment of the maximum IMT. For coronary heart disease, the hazard ratios per 1-SD increment increased 2.5-fold (95% CI, 2.1-3.1) for CAC score and 1.2-fold (95% CI, 1.0-1.4) for IMT. A receiver operating characteristic curve analysis also suggested that CAC score was a better predictor of incident CVD than was IMT, with areas under the curve of 0.81 vs 0.78, respectively. CONCLUSION Although whether and how to clinically use bioimaging tests of subclinical atherosclerosis remains a topic of debate, this study found that CAC score is a better predictor of subsequent CVD events than carotid IMT.

A Meta-analysis of 16 Randomized Controlled Trials to Evaluate Computer-Based Clinical Reminder Systems for Preventive Care in the Ambulatory Setting

OBJECTIVE Computer-based reminder systems have the potential to change physician and patient behaviors and to improve patient outcomes. We performed a meta-analysis of published randomized controlled trials to assess the overall effectiveness of computer-based reminder systems in ambulatory settings directed at preventive care. DESIGN Meta-analysis. SEARCH STRATEGY Searches of the Medline (1966-1994), Nursing and Allied Health (1982-1994), and Health Planning and Administration (1975-1994) databases identified 16 randomized, controlled trials of computer-based reminder systems in ambulatory settings. STATISTICAL METHODS A weighted mixed effects model regression analysis was used to estimate intervention effects for computer and manual reminder systems for six classes of preventive practices. MAIN OUTCOME MEASURE Adjusted odds ratio for preventive practices. RESULTS Computer reminders improved preventive practices compared with the control condition for vaccinations (adjusted odds ratio [OR] 3.09; 95% confidence interval [CI] 2.39-4.00), breast cancer screening (OR 1.88; 95% CI 1.44-2.45), colorectal cancer screening (OR 2.25; 95% CI 1.74-2.91), and cardiovascular risk reduction (OR 2.01; 95% CI 1.55-2.61) but not cervical cancer screening (OR 1.15; 95% CI 0.89-1.49) or other preventive care (OR 1.02; 95% CI 0.79-1.32). For all six classes of preventive practices combined the adjusted OR was 1.77 (95% CI 1.38-2.27). CONCLUSION Evidence from randomized controlled studies supports the effectiveness of data-driven computer-based reminder systems to improve prevention services in the ambulatory care setting.

Risk factors for the progression of coronary artery calcification in asymptomatic subjects: results from the Multi-Ethnic Study of Atherosclerosis (MESA).

Background— The Multi-Ethnic Study of Atherosclerosis (MESA) provides an opportunity to study the association of traditional cardiovascular risk factors with the incidence and progression of coronary artery calcium (CAC) in a large community-based cohort with no evidence of clinical cardiovascular disease. Methods and Results— Follow-up CAC measurements were available for 5756 participants with an average of 2.4 years between scans. The incidence of newly detectable CAC averaged 6.6% per year. Incidence increased steadily across age, ranging from <5% annually in those <50 years of age to >12% in those >80 years of age. Median annual change in CAC for those with existing calcification at baseline was 14 Agatston units for women and 21 Agatston units for men. Most traditional cardiovascular risk factors were associated with both the risk of developing new incident coronary calcium and increases in existing calcification. These included age, male gender, white race/ethnicity, hypertension, body mass index, diabetes mellitus, glucose, and family history of heart attack. Factors also existed that were related only to incident CAC risk, such as low- and high-density lipoprotein cholesterol and creatinine. Diabetes mellitus had the strongest association with CAC progression for blacks and the weakest for Hispanics, with intermediate associations for whites and Chinese. Conclusions— This is the first large multiethnic study reporting on the incidence and progression of CAC. Standard coronary risk factors were generally related to both CAC incidence and progression. Whites had more incident CAC and CAC progression than the other 3 racial/ethnic groups. Except for diabetes mellitus, risk factor relationships were similar across racial/ethnic groups.

Race-ethnic disparities in the impact of stroke risk factors: the northern Manhattan stroke study.

Background and Purpose— Stroke risk factors have been determined in large part through epidemiological studies in white cohorts; as a result, race-ethnic disparities in stroke incidence and mortality rates remained unexplained. The aim in the present study was to compare the prevalence, OR, and etiological fraction (EF) of stroke risk factors among white, blacks, and Caribbean Hispanics living in the same urban community of northern Manhattan. Methods— In this population-based incident case-control study, cases (n=688) of first ischemic stroke were prospectively matched 1:2 by age, sex, and race-ethnicity with community controls (n=1156). Risk factors were determined through in-person assessment. Conditional logistic regression was used to calculate adjusted ORs in each race-ethnic group. Prevalence and multivariate EFs were determined in each race-ethnic group. Results— Hypertension was an independent risk factor for whites (OR 1.8, EF 25%), blacks (OR 2.0, EF 37%), and Caribbean Hispanics (OR 2.1, EF 32%), but greater prevalence led to elevated EFs among blacks and Caribbean Hispanics. Greater prevalence rates of diabetes increased stroke risk in blacks (OR 1.8, EF 14%) and Caribbean Hispanics (OR 2.1 P <0.05, EF 10%) compared with whites (OR 1.0, EF 0%), whereas atrial fibrillation had a greater prevalence and EF for whites (OR 4.4, EF 20%) compared with blacks (OR 1.7, EF 3%) and Caribbean Hispanics (OR 3.0, EF 2%). Coronary artery disease was most important for whites (OR 1.3, EF 16%), followed by Caribbean Hispanics (OR 1.5, EF 6%) and then blacks (OR 1.1, EF 2%). Prevalence of physical inactivity was greater in Caribbean Hispanics, but an elevated EF was found in all groups. Conclusions— The prevalence, OR, and EF for stroke risk factors vary by race-ethnicity. These differences are crucial to the etiology of stroke, as well as to the design and implementation of stroke prevention programs.

A Randomized Trial Comparing Telemedicine Case Management with Usual Care in Older, Ethnically Diverse, Medically Underserved Patients with Diabetes Mellitus

BACKGROUND Telemedicine is a promising but largely unproven technology for providing case management services to patients with chronic conditions who experience barriers to access to care or a high burden of illness. METHODS The authors conducted a randomized, controlled trial comparing telemedicine case management to usual care, with blinding of those obtaining outcome data, in 1,665 Medicare recipients with diabetes, aged 55 years or greater, and living in federally designated medically underserved areas of New York State. The primary endpoints were HgbA1c, blood pressure, and low-density lipoprotein (LDL) cholesterol levels. RESULTS In the intervention group (n = 844), mean HgbA1c improved over one year from 7.35% to 6.97% and from 8.35% to 7.42% in the subgroup with baseline HgbA1c > or =7% (n = 353). In the usual care group (n = 821) mean HgbA1c improved over one year from 7.42% to 7.17%. Adjusted net reductions (one-year minus baseline mean values in each group, compared between groups) favoring the intervention were as follows: HgbA1c, 0.18% (p = 0.006), systolic and diastolic blood pressure, 3.4 (p = 0.001) and 1.9 mm Hg (p < 0.001), and LDL cholesterol, 9.5 mg/dL (p < 0.001). In the subgroup with baseline HgbA1c > or =7%, net adjusted reduction in HgbA1c favoring the intervention group was 0.32% (p = 0.002). Mean LDL cholesterol level in the intervention group at one year was 95.7 mg/dL. The intervention effects were similar in magnitude in the subgroups living in New York City and upstate New York. CONCLUSION Telemedicine case management improved glycemic control, blood pressure levels, and total and LDL cholesterol levels at one year of follow-up.

Differences in the Incidence of Congestive Heart Failure by Ethnicity : The Multi-Ethnic Study of Atherosclerosis

BACKGROUND The relationship between incident congestive heart failure (CHF) and ethnicity as well as racial/ethnic differences in the mechanisms leading to CHF have not been demonstrated in a multiracial, population-based study. Our objective was to evaluate the relationship between race/ethnicity and incident CHF. METHODS The Multi-Ethnic Study of Atherosclerosis (MESA) is a cohort study of 6814 participants of 4 ethnicities: white (38.5%), African American (27.8%), Hispanic (21.9%), and Chinese American (11.8%). Participants with a history of cardiovascular disease at baseline were excluded. Cox proportional hazards models were used for data analysis. RESULTS During a median follow-up of 4.0 years, 79 participants developed CHF (incidence rate: 3.1 per 1000 person-years). African Americans had the highest incidence rate of CHF, followed by Hispanic, white, and Chinese American participants (incidence rates: 4.6, 3.5, 2.4, and 1.0 per 1000 person-years, respectively). Although risk of developing CHF was higher among African American compared with white participants (hazard ratio, 1.8; 95% confidence interval, 1.1-3.1), adding hypertension and/or diabetes mellitus to models including ethnicity eliminated statistical ethnic differences in incident CHF. Moreover, African Americans had the highest proportion of incident CHF not preceded by clinical myocardial infarction (75%) compared with other ethnic groups (P = .06). CONCLUSIONS The higher risk of incident CHF among African Americans was related to differences in the prevalence of hypertension and diabetes mellitus as well as socioeconomic status. The mechanisms of CHF also differed by ethnicity; interim myocardial infarction had the least influence among African Americans, and left ventricular mass increase had the greatest effect among Hispanic and white participants.

Alcohol Intake and Risk of Dementia

Objectives: To examine the association between intake of alcoholic beverages and risk of Alzheimers disease (AD) and dementia associated with stroke (DAS) in a cohort of elderly persons from New York City.

Health insurance coverage of immigrants living in the United States: differences by citizenship status and country of origin.

OBJECTIVES This study examined health insurance coverage among immigrants who are not US citizens and among individuals from the 16 countries with the largest number of immigrants living in the United States. METHODS We analyzed data from the 1998 Current Population Survey, using logistic regression to standardize rates of employer-sponsored coverage by country of origin. RESULTS In 1997, 16.7 million immigrants were not US citizens. Among non-citizens, 43% of children and 12% of elders lacked health insurance, compared with 14% of non-immigrant children and 1% of non-immigrant elders. Approximately 50% of non-citizen full-time workers had employer-sponsored coverage, compared with 81% of non-immigrant full-time workers. Immigrants from Guatemala, Mexico, El Salvador, Haiti, Korea, and Vietnam were the most likely to be uninsured. Among immigrants who worked full-time, sociodemographic and employment characteristics accounted for most of the variation in employer health insurance. For Central American immigrants, legal status may play a role in high un-insurance rates. CONCLUSIONS Immigrants who are not US citizens are much less likely to receive employer-sponsored health insurance or government coverage; 44% are uninsured. Ongoing debates on health insurance reform and efforts to improve coverage will need to focus attention on this group.

A Randomized Trial Comparing Telemedicine Case Management with Usual Care in Older, Ethnically Diverse, Medically Underserved Patients with Diabetes Mellitus: 5 Year Results of the IDEATel Study

CONTEXT Telemedicine is a promising but largely unproven technology for providing case management services to patients with chronic conditions and lower access to care. OBJECTIVES To examine the effectiveness of a telemedicine intervention to achieve clinical management goals in older, ethnically diverse, medically underserved patients with diabetes. DESIGN, Setting, and Patients A randomized controlled trial was conducted, comparing telemedicine case management to usual care, with blinded outcome evaluation, in 1,665 Medicare recipients with diabetes, aged >/= 55 years, residing in federally designated medically underserved areas of New York State. Interventions Home telemedicine unit with nurse case management versus usual care. Main Outcome Measures The primary endpoints assessed over 5 years of follow-up were hemoglobin A1c (HgbA1c), low density lipoprotein (LDL) cholesterol, and blood pressure levels. RESULTS Intention-to-treat mixed models showed that telemedicine achieved net overall reductions over five years of follow-up in the primary endpoints (HgbA1c, p = 0.001; LDL, p < 0.001; systolic and diastolic blood pressure, p = 0.024; p < 0.001). Estimated differences (95% CI) in year 5 were 0.29 (0.12, 0.46)% for HgbA1c, 3.84 (-0.08, 7.77) mg/dL for LDL cholesterol, and 4.32 (1.93, 6.72) mm Hg for systolic and 2.64 (1.53, 3.74) mm Hg for diastolic blood pressure. There were 176 deaths in the intervention group and 169 in the usual care group (hazard ratio 1.01 [0.82, 1.24]). CONCLUSIONS Telemedicine case management resulted in net improvements in HgbA1c, LDL-cholesterol and blood pressure levels over 5 years in medically underserved Medicare beneficiaries. Mortality was not different between the groups, although power was limited. Trial Registration http://clinicaltrials.gov Identifier: NCT00271739.