While black-white and regional disparities in U.S. stroke mortality rates are well documented, the contribution of disparities in stroke incidence is unknown. We provide national estimates of stroke incidence by race and region, contrasting these to publicly available stroke mortality data.
This analysis included 27,744 men and women without prevalent stroke (40.4% black), aged ≥45 years from the REasons for Geographic And Racial Differences in Stroke (REGARDS) national cohort study, enrolled 2003–2007. Incident stroke was defined as first occurrence of stroke over 4.4 years of follow-up. Age-sex–adjusted stroke mortality rates were calculated using data from the Centers for Disease Control and Prevention (CDC) Wide-Ranging Online Data for Epidemiological Research (WONDER) System.
There were 460 incident strokes over 113,469 person-years of follow-up. Relative to the rest of the United States, incidence rate ratios (IRRs) of stroke in the southeastern stroke belt and stroke buckle were 1.06 (95% confidence interval [CI], 0.87–1.29) and 1.19 (95% CI, 0.96–1.47), respectively. The age-sex–adjusted black/white IRRblack was 1.51 (95% CI, 1.26–1.81), but for ages 45–54 years the IRRblack was 4.02 (95% CI, 1.23–13.11) while for ages 85+ it was 0.86 (95% CI, 0.33–2.20). Generally, the IRRsblack were less than the mortality rate ratios (MRRs) across age groups; however, only in ages 55–64 years and 65–74 years did the 95% CIs of IRRsblack not include the MRRblack. The MRRs for regions were within 95% CIs for IRRs.
National patterns of black-white and regional differences in stroke incidence are similar to those for stroke mortality; however, the magnitude of differences in incidence appear smaller.
Background and Purpose
Black/white disparities in stroke incidence are well-documented, but few studies have assessed the contributions to the disparity. Here we assess the contribution of “traditional” risk factors.
25,714 black and white men and women, aged 45+ and stroke-free at baseline were followed for an average of 4.4 years to detect stroke. Mediation analysis employing proportional hazards analysis assessed the contribution of “traditional” risk factors to racial disparities.
At age 45, incident stroke risk was 2.90 (95% CI: 1.72 – 4.89) times more likely in blacks than whites, and 1.66 (95% CI: 1.34 – 2.07) times at age 65. Adjustment for risk factors attenuated these excesses by 40% and 45%, respectively, resulting in relative risks of 2.14 (95% CI: 1.25 – 3.67) and 1.35 (95% CI: 1.08 – 1.71). Approximately one-half of this mediation is attributable to systolic blood pressure. Further adjustment for socioeconomic factors resulted in total mediation of 47% and 53% to relative risks of 2.01 (95% CI: 1.16 – 3.47) and 1.30 (1.03 – 1.65) respectively.
Between ages 45 to 65 years, approximately half of the racial disparity in stroke risk is attributable to traditional risk factors (primarily systolic blood pressure) and socioeconomic factors, suggesting a critical need to understand the disparity in the development of these traditional risk factors. Because half of the excess stroke risk in blacks is not attributable to traditional risk factors and socioeconomic factors, differential racial susceptibility to risk factors, residual confounding or non-traditional risk factors may also play a role.
stroke; risk factors; hypertension; diabetes; mediation analysis
Background and Purpose
Previously in the REasons for Geographic And Racial Differences in Stroke (REGARDS) cohort, we found 18% of the stroke/TIA-free study population reported ≥ 1 stroke symptom (SS) at baseline. We sought to evaluate the additional impact of these stroke symptoms (SS) on risk for subsequent stroke.
REGARDS recruited 30,239 U.S. blacks and whites, aged 45+ in 2003–7, who are being followed every 6 months for events. All stroke events are physician-verified; those with prior diagnosed stroke or TIA are excluded from this analysis. At baseline, participants were asked six questions regarding stroke symptoms. Measured stroke risk factors were components of the Framingham Stroke Risk Score (FSRS).
After excluding those with prior stroke or missing data, there were 24,412 participants in this analysis, with a median follow-up of 4.4 years. Participants were 39% black, 55% female, and had median age of 64 years. There were 381 physician-verified stroke events. The FSRS explained 72.0% of stroke risk; individual components explained between 0.2% (LVH) and 5.7% (age + race) of stroke risk. After adjustment for FSRS factors, SS were significantly related to stroke risk: for each SS reported, the risk of stroke increased by 21% per symptom.
Among participants without self-reported stroke or TIA, prior SS are highly predictive of future stroke events. Compared to FSRS factors, the impact of SS on the prediction of future stroke was almost as large as the impact of smoking and hypertension, and larger than the impact of diabetes and heart disease.
Acute Stroke; Aphasia; Ischemia; Risk Factors; TIA; Transient Ischemic Attack
Background and Purpose
We compared the associations of self-reported atrial fibrillation (SR-AF) and electrocardiogram-detected AF (ECG-AF) with incident stroke in the REGARDS study.
27,109 participants aged ≥45 years without prior stroke were included in this analysis. Stroke cases were identified and adjudicated during an average of 4.4 years of follow-up. Cox proportional hazards analysis was used to calculate hazard ratios of SR-AF, ECG-AF, and AF detected by either method with incident stroke. We also examined the predictive ability of the Framingham Stroke Risk Score (FSRS) where the component AF was defined by different methods.
After adjustment for components of the FSRS, SR-AF, ECG-AF, and AF by either method were predictive of incident stroke [HR (95% CI): 1.41 (1.05,1.88), 1.90 (1.10,3.27), 1.53 and (1.16,2.01), respectively]. When self-report, ECG or either method, separately, were considered as the method of AF ascertainment in the FSRS, the Hazard ratios per 1% increase in the FSRS were identical across AF ascertainment methods [1.04 (1.03,1.04); 1.04 (1.04,1.05); 1.04 (1.03,1.04) respectively].
SR-AF is a strong predictor of stroke that can be used interchangeably or in combination with ECG-AF in stroke risk prediction models.
Atrial fibrillation; self-report; Electrocardiogram
Longitudinal cohort studies normally identify and adjudicate incident events detected during follow-up by retrieving medical records. There are several reasons why the adjudication process may not be successfully completed for a suspected event including the inability to retrieve medical records from hospitals and an insufficient time between the suspected event and data analysis. These “incomplete adjudications” are normally assumed not to be events, an approach which may be associated with loss of precision and introduction of bias. In this article, the authors evaluate the use of multiple imputation methods designed to include incomplete adjudications in analysis. Using data from the REasons for Geographic And Racial Differences in Stroke (REGARDS) Study, 2008−2009, they demonstrate that this approach may increase precision and reduce bias in estimates of the relations between risk factors and incident events.
cohort studies; imputation; longitudinal studies; missing data
There are racial and geographic disparities in stroke mortality, with higher rates among African Americans (AAs) and those living in the southeastern US (‘stroke belt’). Racial and geographic differences in dyslipidemia prevalence, awareness, treatment and control may, in part, account for the observed disparities in stroke mortality.
Reasons for Geographic and Racial Differences in Stroke (REGARDS) is a national observational study of community-dwelling black and white participants aged 45 and older, with oversampling from the stroke belt. As of January 15, 2007, 26,122 participants were enrolled and a fasting lipid panel was available of 21,068. Awareness, treatment and control of dyslipidemia were estimated overall and compared across race-sex-region strata.
There were 55% of the participants with dyslipidemia and no racial differences in prevalence. Adjusting for demographic and established stroke risk factors, AAs had a lower prevalence (OR 0.74; 95% CI: 0.66, 0.77) and were less likely to be aware (0.69; 0.61, 0.78), treated (0.77; 0.67, 0.89) and controlled (0.67; 0.58, 0.77) than whites. There was lower control outside of the stroke belt (0.87; 0.76, 0.99).
Racial, but not geographic, differences in dyslipidemia management may play a role in the excess stroke burden in the Southeast.
Cholesterol; Risk factors; Risk factor management; Racial differences; Stroke prevention
Obesity management requires understanding of the mortality risks associated with different adiposity measures.
Setting and Participants
5,805 adults with BMI ≥ 18.5 and stage 1–4 CKD defined by a spot urine albumin-creatinine ratio ≥ 30 mg/g and/or an estimated glomerular filtration rate < 60 ml/min/1.73 m2 enrolled in the REasons for Geographic and Racial Differences in Stroke (REGARDS) study
Body mass index (BMI) in kg/m2 categorized as 18.5–24.9, 25.0–29.9, 30.0–34.9, 35.0–39.9 and ≥ 40 kg/m2 and waist circumference categorized as < 80, 80–87.9, 88–97.9, 98–107.9, and ≥ 108 cm in women and < 94, 94–101.9, 102–111.9, 112–121.9, and ≥122 cm in men.
All cause mortality
BMI and WC were measured using a standardized protocol during the home visit.
A total of 686 deaths (11.8%) occurred during a median follow-up of 4 years. Compared to the referent BMI category 25–29.9 kg/m2, hazard ratios for mortality were 1.27 (95% CI, 0.96–1.69) for BMI < 25 kg/m2, and 0.84 (95% CI, 0.62–1.13), 0.81 (0.52–1.26) and 0.95 (95% CI, 0.54–1.65) for BMI categories 30–34.9, 35–39.9 and ≥ 40 kg/m2, respectively, after adjustment for covariates including waist circumference. In contrast, after adjustment for covariates including BMI, higher mortality rates were noted for all waist circumference categories compared to the referent (< 80 cm in women and < 94 cm in men) with hazard ratios 1.04 (95% CI, 0.77–1.41) for waist circumference 80–87.9 in women and 94–101.9 in men, 1.29 (95% CI, 0.92–1.81) for waist circumference 88–97.9 in women and 102–111.9 in men, 1.72 (95% CI, 1.12–2.62) for waist circumference 98–107.9 in women and 112–121.9 in men, and 2.09 (95% CI, 1.26–3.46) for waist circumference ≥ 108 in women and ≥ 122 in men.
BMI and waist circumference measured at baseline only.
waist circumference should be considered in conjunction with BMI when assessing mortality risk associated with obesity in adults with CKD.
Obesity; waist circumference; mortality; chronic kidney disease
To determine whether incidence of impaired cognitive screening status is higher in the southern Stroke Belt region of the United States than in the remaining U.S.
A national cohort of adults ≥ age 45 was recruited by the Reasons for Geographic and Racial Differences in Stroke (REGARDS) study from 2003–2007. Participants’ global cognitive status was assessed annually by telephone with the Six-item Screener (SIS) and every two years with fluency and recall tasks. Participants who reported no stroke history and who were cognitively intact at enrollment (SIS > 4 of 6) were included (N = 23,913, including 56% women, 38% African Americans and 62% European Americans, 56% Stroke Belt residents and 44% from the remaining contiguous United States and the District of Columbia). Regional differences in incident cognitive impairment (SIS score ≤ 4) were adjusted for age, sex, race, education, and time between first and last assessments.
1,937 participants (8.1%) declined to an SIS score ≤ 4 at their most recent assessment, over a mean of 4.1 (± 1.6) years. Residents of the Stroke Belt had greater adjusted odds of incident cognitive impairment than non-Belt residents (OR = 1.18; 95% CI 1.07 – 1.30). All demographic factors and time independently predicted impairment.
Regional disparities in cognitive decline mirror regional disparities in stroke mortality, suggesting shared risk factors for these adverse outcomes. Efforts to promote cerebrovascular and cognitive health should be directed to the Stroke Belt.
This paper documents individual asthma action plan presence and quick relief medication (albuterol) availability for elementary students enrolled in five Alabama school systems.
Patients and Methods
Data were obtained during baseline data collection (fall 2005) of a school-based supervised asthma medication trial. All students attended 1 of 36 participating elementary schools across five school systems in Jefferson County, Alabama. In addition, they had to have physician-diagnosed asthma requiring daily controller medication. Each school system had its own superintendent and elected school board. Asthma action plan presence and albuterol availability was confirmed by study personnel. Asthma action plans had to contain daily and acute asthma management instructions. Predictors of asthma action plan presence and albuterol availability were also investigated. Associations between albuterol availability and self-reported characteristics including health care utilization prior to study enrollment and outcomes during the study baseline period were also investigated.
Enrolled students had a mean (SD) age of 11.0 (2.1) years, 91% were African American, and 79% had moderate persistent asthma. No student had a complete asthma action plan on file and only 14% had albuterol physically available at school. Albuterol availability was not predicted by gender, race, insurance status, second-hand smoke exposure, need for pre-exercise albuterol, asthma severity, or self-reported health care utilization prior to study enrollment. Albuterol availability did not predict school absences, red/yellow peak flow recordings, or medication adherence during the study's baseline period.
Despite policies permitting students to possess albuterol, few elementary students across five independent school systems in Alabama actually had it readily available at school.
There is growing interest in determining the degree of anemia, which is clinically significant. The goal of this study was to determine the association between hemoglobin concentration and cognitive impairment in a large sample of U.S. adults.
We used cross-sectional data from 19,701 adults participating in the REasons for Geographic And Racial Differences in Stroke study. Cognitive impairment was defined as a score of 4 or less on the six-item screener. Hemoglobin was analyzed in 1 g/dL increments relative to the World Health Organization (WHO) threshold (<13 g/dL for men and <12 g/dL for women).
The mean hemoglobin concentration was 13.7 ± 1.5 g/dL. The prevalence of cognitive impairment increased from 4.3% among individuals with a hemoglobin >3 g/dL above the WHO threshold to 16.8% for those with a hemoglobin ≥2 g/dL below the WHO threshold. After adjustment for demographics, chronic health conditions, health status, and inflammation, the association between reduced hemoglobin and cognitive impairment was attenuated and no longer significant, including among those with hemoglobin ≥2 g/dL below the WHO threshold (odds ratio 1.39, 95% confidence interval = 0.94–2.04). A test for linear trend was of borderline significance (p value = .06). For 94% of the sample within 2 g/dL of the WHO threshold, there was no relationship between hemoglobin concentration and the odds of cognitive impairment. The associations did not differ by sex and race.
Within a large sample of community-dwelling adults, there was no significant association between hemoglobin concentration and cognitive impairment after multivariable adjustment.
Hemoglobin; Anemia; Cognitive impairment
Chronic kidney disease (CKD) and albuminuria are associated with increased risk of all-cause mortality.
Prospective observational cohort study
Setting and Participants
17,393 participants (mean age, 64.3 ± 9.6 years) in the REGARDS (Reasons for Geographic and Racial Differences in Stroke) Study.
Estimated glomerular filtration rate (eGFR), urinary albumin-creatinine ratio (ACR).
All-cause mortality (710 deaths); median duration of follow-up: 3.6 years.
Measurements and Analysis
Categories of eGFR (90– <120, 60–<90, 45–<60, 30–<45, and 15–<30 mL/min/1.73 m2) and urinary ACR (<10 mg/g or normal, 10–<30 mg/g or high normal, 30–300 mg/g or high, and >300 mg/g or very high). Cox’s proportional hazards models were adjusted for demographic factors, cardiovascular covariates, and hemoglobin.
The background all-cause mortality rate for participants with normal ACR, eGFR of 90–<120 mL/min/1.73 m2 and no CHD was 4.3 deaths/1,000 person-years. Higher ACR was associated with an increased multivariable adjusted hazard ratio for all-cause mortality within each eGFR category. Reduced eGFR was associated with higher adjusted hazard ratio for all-cause mortality for participants with high normal (P value = 0.01) and high (P value <0.001) ACR values, but not for those with normal or very high ACR values.
Only one laboratory assessment for serum creatinine and ACR was available
Increased albuminuria was an independent risk factor for all-cause mortality. Reduced eGFR was associated with increased mortality risk among those with high normal and high ACR. The mortality rate was low in the normal ACR group and increased in the very high ACR group but did not vary with eGFR in these groups.
Complex diseases often aggregate within families and using the history of family members’ disease can potentially increase the accuracy of the risk assessment and allow clinicians to better target on high risk individuals. However, available family risk scores do not reflect the age of disease onset, gender and family structures simultaneously. In this paper, we propose an alternative approach for a family risk score, the stratified log-rank family score (SLFS), which incorporates the age of disease onset of family members, gender differences and the relationship among family members. Via simulation, we demonstrate that the new SLFS is more closely associated with the true family risk for the disease and more robust to family sizes than two existing methods. We apply our proposed method and the two existing methods to a study of stroke and heart disease. The results show that assessing family history can improve the prediction of disease risks and the SLFS has strongest positive associations with both myocardial infarction and stroke.
family history; family risk; family history score; age of onset; heart disease
Stroke mortality rates differ by race and region, and smoking and exposure to secondhand smoke are associated with stroke. We evaluated regional and racial differences in current smoking and secondhand smoke exposure among participants in the Reasons for Geographic and Racial Differences in Stroke (REGARDS) study.
African American and white adults (n = 26,373) aged 45 years or older were recruited during 2003 through 2007. Logistic regression was used to examine the likelihood of current smoking and secondhand smoke exposure by race (African American vs white) and region. We compared the buckle of the stroke belt (the coastal plain region of North Carolina, South Carolina, and Georgia) with the stroke belt (the remainder of North Carolina, South Carolina, and Georgia, plus Alabama, Mississippi, Tennessee, Arkansas, and Louisiana) and compared each of these regions with the remaining contiguous states.
Among whites, no regional differences in current smoking were seen, but among African Americans, the odds of current smoking were 5% lower in the stroke belt, and 24% lower in the stroke buckle than those in the nonbelt region. Similarly, among whites no regional differences in exposure to secondhand smoke were found, whereas among African Americans, the odds of being exposed to secondhand smoke were 14% lower in the stroke buckle than for nonbelt residents.
These data suggest that rates of current smoking and secondhand smoke exposure are not higher in regions that have higher stroke mortality and therefore cannot contribute to geographic disparities; nevertheless, given that 15% of our participants reported current smoking and 16% reported secondhand smoke exposure, continued implementation of tobacco control policies is needed.
Asthma exacerbations are seasonal with the greatest risk in elementary-age students occurring shortly after returning to school following summer break. Recent research suggests that this seasonality in children is primarily related to viral respiratory tract infections. Regular hand washing is the most effective method to prevent the spread of viral respiratory infections; unfortunately, achieving hand washing recommendations in schools is difficult. Therefore, we designed a study to evaluate the effect of hand sanitizer use in elementary schools on exacerbations among children with asthma.
To describe the process of redesigning the trial in response to changes in the safety profile of the hand sanitizer as well as changes in hand hygiene practice in the schools.
The original trial was a randomized, longitudinal, subject-blinded, placebo-controlled, community-based crossover trial. The primary aim was to evaluate the incremental effectiveness of hand sanitizer use in addition to usual hand hygiene practices to decrease asthma exacerbations in elementary-age children. Three events occurred that required major modifications to the original study protocol: (1) safety concerns arose regarding the hand sanitizer’s active ingredient; (2) no substitute placebo hand sanitizer was available; and (3) community preferences changed regarding hand hygiene practices in the schools.
The revised protocol is a randomized, longitudinal, community-based crossover trial. The primary aim is to evaluate the incremental effectiveness of a two-step hand hygiene process (hand hygiene education plus institutionally provided alcohol-based hand sanitizer) versus usual care to decrease asthma exacerbations. Enrollment was completed in May 2009 with 527 students from 30 schools. The intervention began in August 2009 and will continue through May 2011. Study results should be available at the end of 2011.
The changed design does not allow us to directly measure the effectiveness of hand sanitizer use as a supplement to traditional hand washing practices.
The need to balance a rigorous study design with one that is acceptable to the community requires investigators to be actively involved with community collaborators and able to adapt study protocols to fit changing community practices.
There are pronounced disparities among black compared to white Americans for risk of end-stage renal disease. This study examines whether similar relationships exist between poverty and racial disparities in chronic kidney disease (CKD) prevalence.
We studied 22,538 participants in the REasons for Geographic And Racial Differences in Stroke (REGARDS) cohort study. We defined individual poverty as family income below USD 15,000 and a neighborhood as poor if 25% or more of the households were below the federal poverty level.
As the estimated glomerular filtration rate (GFR) declined from 50–59 to 10–19 ml/min/ 1.73 m2, the black:white odds ratio (OR) for impaired kidney function increased from 0.74 (95% CI 0.66, 0.84) to 2.96 (95% CI 1.96, 5.57). Controlling for individual income below poverty, community poverty, demographic and comorbid characteristics attenuated the black:white prevalence to an OR of 0.65 (95% CI 0.57, 0.74) among individuals with a GFR of 59–50 ml/min/1.73 m2 and an OR of 2.21 (95% CI 1.25, 3.93) among individuals with a GFR between 10 and 19 ml/min/ 1.73 m2.
Household, but not community poverty, was independently associated with CKD and attenuated but did not fully account for differences in CKD prevalence between whites and blacks.
Chronic kidney disease; Poverty; Racial disparities
To minimize participants’ burden and the need for disrobing, a 7-lead electrocardiogram (ECG) recording using a single mid-sternal chest lead was recorded at the initial stages of The REasons for Geographic And Racial Differences in Stroke (REGARDS) Study. ECG-detected left ventricular hypertrophy (ECG-LVH) by Cornell voltage (RaVL +SV3) cannot be assessed from this method because of the absence of V3. We examined the possibility that the S wave amplitude in the mid-sternal lead (SV) could be used as a surrogate for SV3.
The REGARDS study is a US national study where 7-lead ECGs were performed in 8,330 (29%) participants and standard 12-lead EGCs were performed in 20,811 (71%). Cornell voltage was calculated as the sum of aVL amplitude + SV (in the 7-lead group) or SV3 (in the 12-lead group). Logistic regression analysis was used to examine and compare the magnitude of the association between the LVH risk factors with ECG-LVH in both groups, and Cox Proportional Hazards analysis was used to examine and compare the hazard ratios of overall mortality and cardiovascular mortality associated with ECG-LVH in both groups.
Regardless of the Cornell voltage calculation method, ECG-LVH was significantly associated with LVH risk factors, and with the exception of sex there was no evidence of a difference in the magnitude of the association. ECG-LVH from both approaches were significantly and similarly associated with both all cause and cardiovascular mortality.
ECG-LVH by Cornell voltage calculated from a 7-lead ECG (using SV in the formula) has demographic and clinical associations that are similar to that calculated from a standard 12-lead ECG (using SV3). In epidemiologic studies recording 7-lead ECG, SV could be used as an alternative to SV3 in the Cornell voltage formula.
Alcohol intake has been shown to have a J-shaped association with blood pressure (BP). However, this association has not been examined in mixed race populations or in people with diabetes where tighter blood pressure control is recommended. Participants in the REGARDS study who were 45 years or older (n = 30,239) were included. Medical history (including self-reported alcohol intake) was collected by telephone while blood collection and clinical measurements were done during an in-home visit. We defined diabetes as use of medications and/or fasting glucose ≥ 126 mg/dL and hypertension as use of blood pressure lowering medications and/or BP ≥ 140/90 mmHg or BP ≥ 130/80 mmHg in people with diabetes. After adjustment for confounders, heavy drinking was associated with an increased odds of hypertension (OR = 1.59; 95% CI = 1.37, 1.87). Diabetes and gender significantly modified (interaction P < 0.05 for both) the association between alcohol use and hypertension, although heavy drinking remained associated with increased odds of hypertension in sub-group analyses. We did not observe the previously described J-shaped relationship in any sub-group except white females. These data suggest heavy alcohol consumption is associated with poor BP control and that heavy drinkers may want to consider limiting alcohol intake in order to manage hypertension.
diabetes; race; alcohol; blood pressure; hypertension
The purpose of the study is to determine if functional status and quality of life (QoL) vary with glomerular filtration rate (GFR) among older adults.
We studied adults aged 45 years and older participating in the REasons for Geographic And Racial Differences in Stroke (REGARDS) cohort study. Data included demographic and health information, serum creatinine and hemoglobin, the 4-item Center for Epidemiologic Studies Depression Scale (CES-D-4), the 4-item Cohen's Perceived Stress Scale (PSS-4), reported health status and inactivity and the Medical Outcomes Study Short Form-12 (SF-12) QoL scores.
CKD (GFR <60 ml/min/1.73 m2) was present in 11.6% of the subjects. As GFR declined, the SF-12 physical component score, adjusted for other participant attributes, declined from 38.9 to 35.9 (p = 0.0001). After adjustment for other risk factors, poorer personal health scores (p < 0.0001) and decreased physical activity (p < 0.0001) were reported as GFR declined. In contrast, after adjusting for other participant characteristics, depression scores and stress scores and the mental component score of the SF-12 were not associated with kidney function.
Older individuals with CKD in the US population experience an increased prevalence of impaired QoL that cannot be fully explained by other individual characteristics.
Functional status; Quality of life; Chronic kidney disease; End-stage renal disease; Glomerular filtration rate; REGARDS cohort study; Medical Outcomes Study Short Form-12
Among persons treated for hypertension, Blacks are more likely to have uncontrolled blood pressure compared to Whites. Few studies have focused on trust in physicians as a potential contributor to this disparity in blood pressure (BP) control. The primary objective of this study was to assess the relationship between trust in physicians and blood pressure control among Blacks and Whites being treated for hypertension.
Cross-sectional analysis of baseline data collected from the REasons for Geographic And Racial Differences in Stroke cohort, a US national, population-based cohort study. Participants were recruited by telephone from 2003–2007, completed a telephone survey, and had BP measured during an in-home visit.
2843 Black and White adults aged >45 years with treated hypertension.
Main Outcome Measures
Uncontrolled blood pressure was defined as systolic blood pressure >140 mm Hg or diastolic blood pressure >90 mm Hg. For participants with diabetes, renal disease, or self-reported previous myocardial infarction, uncontrolled blood pressure was defined as systolic blood pressure >130 mm Hg or diastolic blood pressure >80 mm Hg.
Trust in physicians was not associated with uncontrolled blood pressure in either unadjusted (odd ratio [OR] 1.07; 95% confidence interval [CI] 0.92, 1.25) or adjusted analyses (OR 0.97; 0.83, 1.14). Both Black race (OR 1.58; 1.36, 1.84) and imperfect medication adherence (OR 1.56; 1.31, 1.86) were associated with higher odds of uncontrolled blood pressure.
Trust in physicians was not related to blood pressure control among Blacks and Whites with treated hypertension in this sample. The racial disparity in blood pressure control was not completely explained by trust in physicians or medication adherence, and a better understanding of the mechanisms leading to this disparity is needed.
Hypertension; Trust; Disparities
Pedestrian injuries are among the leading causes of morbidity and mortality in middle childhood. One limitation to existing pedestrian safety interventions is that they do not provide children with repeated practice needed to develop the complex perceptual and cognitive skills required for safe street-crossing. Virtual reality (VR) offers training through repeated unsupervised practice without risk; automated feedback on success of crossings; adjustment of traffic to match children’s skill; and a fun, appealing environment for training.
Test efficacy of VR to train child pedestrians in safe street-crossing.
Birmingham, Alabama, USA.
A randomized controlled trial is underway with an expected sample of four groups of 60 children ages 7-8 (total N = 240). One group receives training in an interactive, immersive virtual pedestrian environment. A second receives pedestrian safety training via widely-used video and computer strategies. The third group receives what is judged to be the most efficacious treatment currently available, individualized behavioral training at streetside locations. The fourth group serves as a no-contact control group. All participants are exposed to a range of field- and laboratory-based measures of pedestrian skill during baseline and post-intervention visits, as well as during a six-month follow-up assessment.
Primary analyses will be conducted through linear mixed models testing change over time in the four intervention groups. Three pedestrian safety measures will serve as primary outcomes: temporal gap before initiating crossing, temporal gap remaining after crossing, and attention to traffic while waiting to cross.
Clinical Trial Registration
This study is registered at the US government website, www.clinicaltrials.gov, under the title, “Using Virtual Reality to Train Children in Pedestrian Safety”, registration number NCT00850759.
pedestrian; safety; injury; children; virtual reality; street-crossing
Evidence is mounting regarding the clinically significant effect of temperature on blood pressure.
In this cross-sectional study the authors obtained minimum and maximum temperatures and their respective previous week variances at the geographic locations of the self-reported residences of 26,018 participants from a national cohort of blacks and whites, aged 45+. Linear regression of data from 20,623 participants was used in final multivariable models to determine if these temperature measures were associated with levels of systolic or diastolic blood pressure, and whether these relations were modified by stroke-risk region, race, education, income, sex hypertensive medication status, or age.
After adjustment for confounders, same-day maximum temperatures 20°F lower had significant associations with 1.4 mmHg (95% CI: 1.0, 1.9) higher systolic and 0.5 mmHg (95% CI: 0.3, 0.8) higher diastolic blood pressures. Same-day minimum temperatures 20°F lower had a significant association with 0.7 mmHg (95% CI: 0.3, 1.0) higher systolic blood pressures but no significant association with diastolic blood pressure differences. Maximum and minimum previous-week temperature variabilities showed significant but weak relationships with blood pressures. Parameter estimates showed effect modification of negligible magnitude.
This study found significant associations between outdoor temperature and blood pressure levels, which remained after adjustment for various confounders including season. This relationship showed negligible effect modification.
The Justification of the Use of Statins in Primary Prevention: an Intervention Trial Using Rosuvastatin (JUPITER) reported reduced cardiovascular and all-cause mortality with statin treatment in patients with elevated C-reactive protein (CRP) and average cholesterol, who were not eligible for lipid-lowering treatment based on existing guidelines. We determined the prevalence of eligibility and mortality in a general population sample based on eligibility for statin treatment using JUPITER criteria. We studied 30,229 participants of the REasons for Geographic And Racial Differences in Stroke (REGARDS) cohort, an observational study of US African-American and white participants aged 45 and older, enrolled in their homes between 2003–2007, and followed biannually by telephone. Among 11,339 participants age-eligible for JUPITER and without a vascular diagnosis or using lipid-lowering treatment, 21% (2,342) met JUPITER entry criteria. Compared to JUPITER participants, they had similar LDL cholesterol and CRP, were more often women, black, had metabolic syndrome and used aspirin for cardioprotection. Over 3.5 years follow-up, the mortality rate among REGARDS participants eligible for JUPITER was 1.17 per 100 person-years (95% CI 0.94–1.42). Compared to those otherwise JUPITER eligible who had CRP <2 mg/L (n=2,620), those with CRP ≥2 mg/L had a multivariable-adjusted relative risk of 1.5 (95% CI, 1.1–2.2) for total mortality. In conclusion, 21% not otherwise eligible would be newly eligible for lipid-lowering treatment based on JUPITER trial eligibility.
cardiovascular risk factors; mortality; statin; C-reactive protein
Background and Purpose
The prevalence of stroke is increased in individuals with heart failure (HF). Stroke mechanism in HF may be cardiogenic embolism or cerebral hypoperfusion. Stroke risk increases with decreasing ejection fraction and low cardiac output is associated with hypotension and poor survival. We here examine the relationship between blood pressure level, history of stroke/TIA and HF.
We compared the prevalence of self-reported history of stroke or TIA in the REasons for Geographic And Racial Differences in Stroke (REGARDS) participants with HF (as defined by current digoxin use) and without HF. We excluded participants with atrial fibrillation or missing data. We examined the relationship between HF and history of stroke/TIA within tertiles of systolic blood pressure (SBP), adjusting for patient demographic and health characteristics.
Prevalent stroke/TIA were reported by 66 (26.3%) of 251 participants with and 1,805 (8.5%) of 21,202 participants without HF (p<0.0001). Within each tertile of SBP, the unadjusted OR (95%CI) for prior stroke/TIA among those with HF compared to those without HF (the reference group) was, 4.0 (2.8-5.8) for SBP<119.5mmHg, 2.7(1.8-3.9) for SBP≥119.5,<131.5mmHg and 2.3 (1.6-3.2) for SBP ≥131.5mmHg. After adjustment, the relationship between prior stroke/TIA and HF remained significant only within the lowest tertile of SBP (<119.5mmHg) (3.0; 1.5-6.1).
The odds of prevalent self-reported stroke/TIA are increased in participants with HF, and most markedly increased in participants with low SBP. Longitudinal data are needed to determine whether this reflects stroke/TIA secondary to thromboembolism from poor cardiac function or secondary to cerebral hypoperfusion.
Brain infarction; cardiac disease; hypertension
Undertreatment of osteoporosis has been recognized as a common problem in selected patient subgroups. However, primary prevention has been hampered by limited risk assessment tools that can be applied to large populations.
Using clinical risk factors with a new tool from the World Health Organization (FRAX) and recommendations from the National Osteoporosis Foundation (NOF), we evaluated fracture risk and osteoporosis treatment in a US cohort.
African Americans and Caucasians recruited from 2003–7 across the US as part of a longitudinal study.
The number of persons receiving prescription osteoporosis medications was assessed by race, sex, and fracture risk. Multivariable logistic regression evaluated the association between receipt of osteoporosis medications and fracture risk after controlling for potential confounders.
Among 24,783 participants, estimated fracture risk was highest for Caucasian women. After multivariable adjustment for fracture-related risk factors, the likelihood of receipt of osteoporosis medications among African Americans was lower than among Caucasians [odds ratio (OR) = 0.44, 95% confidence interval (CI) 0.37, 0.53] and for men compared to women (OR = 0.08, 95% CI 0.06–0.10). Even for the highest risk group, Caucasian women with 10-year hip fracture risk ≥3% (n = 3,025, 39.7%), only 26% were receiving treatment.
A substantial gap exists between 2008 NOF treatment guidelines based on fracture risk and the receipt of prescription osteoporosis medications. This gap was particularly notable for African Americans and men. FRAX is likely to be useful to assess risk at a population level and identify high-risk persons in need of additional evaluation.
osteoporosis; fracture; African American; Caucasian; epidemiology; FRAX; bisphosphonate
Geographic variation in risk factors may underlie geographic disparities in coronary heart disease (CHD) and stroke mortality.
Framingham CHD Risk Score (FCRS) and Stroke Risk Score (FSRS) were calculated for 25,770 stroke-free and 22,247 CHD-free participants from the REasons for Geographic And Racial Differences in Stroke cohort. Vital statistics provided age-adjusted CHD and stroke mortality rates. In an ecologic analysis, the age-adjusted, race-sex weighted, average state-level risk factor levels were compared to state-level mortality rates.
There was no relationship between CHD and stroke mortality rates (r = 0.04; p = 0.78), but there was between CHD and stroke risk scores at the individual (r = 0.68; p < 0.0001) and state (r = 0.64, p < 0.0001) level. There was a stronger (p < 0.0001) association between state-level FCRS and state-level CHD mortality (r = 0.28, p = 0.18), than between FSRS and stroke mortality (r = 0.12, p = 0.56).
Weak associations between CHD and stroke mortality and strong associations between CHD and stroke risk scores suggest geographic variation in risk factors may not underlie geographic variations in stroke and CHD mortality. The relationship between risk factor scores and mortality was stronger for CHD than stroke.
Stroke; Coronary Heart Disease; Geography; Risk Factors; Mortality