Abstract 19554: Lipoprotein(a) and Risk of Ischemic Stroke in the Reasons for Geographic and Racial Differences in Stroke (REGARDS) Study

Circulation ◽  
2015 ◽  
Vol 132 (suppl_3) ◽  
Author(s):  
Kristine S Alexander ◽  
Neil A Zakai ◽  
Fred Unverzagt ◽  
Virginia Wadley ◽  
Brett M Kissela ◽  
...  
Keyword(s):  
Ischemic Stroke ◽  
Racial Differences ◽  
Stroke Risk ◽  
Proportional Hazards ◽  
Continuous Variable ◽  
Cox Proportional Hazards ◽  
Stroke Incidence ◽  
Lipoprotein A ◽  
Cox Proportional Hazards Models ◽  
Regards Study

Background: Increased lipoprotein (a) (Lp(a)) is associated with coronary risk, but links with stroke have been less consistent. Blacks have 2-4-fold higher Lp(a) levels than whites, and have higher stroke incidence than whites, but have been under-represented in studies of Lp(a) and stroke to date. Hypothesis: Lp(a) is a risk factor for ischemic stroke, and this risk differs by race. Methods: REGARDS recruited 30,239 black and white U.S. men and women in 2003-7 to study regional and racial differences in stroke mortality. We measured Lp(a) by immunonepholometric assay in 572 cases of incident ischemic stroke and a 1,104-person cohort random sample. The hazard ratio of stroke by baseline Lp(a) was calculated using Cox proportional hazards models, stratified by race. Lp(a) was modeled both as a continuous variable (per sex- and race-specific SD) and in sex- and race-specific quartiles, given known differences in distributions by race and sex. Results: As shown in the Figure, being in the 4 th vs 1 st Lp(a) quartile was associated with ischemic stroke in black but not white participants, adjusted for age and sex (Model 1). The HRs were essentially unchanged with added adjustment for stroke risk factors (Model 2). There was no significant association between Lp(a) as a continuous variable and stroke, though race-specific patterns were similar. There remained no association between Lp(a) and stroke in whites when we used the sex- and race-specific 90 th percentile as a cut-off (HR: 0.91 95% CI: 0.52, 1.60). Discussion: Lp(a) was associated with ischemic stroke risk in black but not white REGARDS participants, this might partly explain the black/white disparity in stroke. Further studies in racially diverse groups are necessary to confirm these findings. Figure 1. Hazard ratios for Lp(a) and stroke in blacks and whites, per quartile (compared with first quartile) and SD.

scholarly journals High sodium:potassium intake ratio increases the risk for all-cause mortality: the REasons for Geographic And Racial Differences in Stroke (REGARDS) study

2013 ◽  
Vol 2 ◽  
Author(s):  
Suzanne E. Judd ◽  
Kristal J. Aaron ◽  
Abraham J. Letter ◽  
Paul Muntner ◽  
Nancy S. Jenny ◽  
...  
Keyword(s):  
Racial Differences ◽  
Proportional Hazards ◽  
Reference Group ◽  
Cox Proportional Hazards ◽  
Stroke Incidence ◽  
Black And White ◽  
Cox Proportional Hazards Models ◽  
Group Data ◽  
All Cause Mortality ◽  
Regards Study

AbstractIncreased dietary Na intake and decreased dietary K intake are associated with higher blood pressure. It is not known whether the dietary Na:K ratio is associated with all-cause mortality or stroke incidence and whether this relationship varies according to race. Between 2003 and 2007, the REasons for Geographic And Racial Differences in Stroke (REGARDS) cohort enrolled 30 239 black and white Americans aged 45 years or older. Diet was assessed using the Block 98 FFQ and was available on 21 374 participants. The Na:K ratio was modelled in race- and sex-specific quintiles for all analyses, with the lowest quintile (Q1) as the reference group. Data on other covariates were collected using both an in-home assessment and telephone interviews. We identified 1779 deaths and 363 strokes over a mean of 4·9 years. We used Cox proportional hazards models to obtain multivariable-adjusted hazard ratios (HR). In the highest quintile (Q5), a high Na:K ratio was associated with all-cause mortality (Q5 v. Q1 for whites: HR 1·22; 95 % CI 1·00, 1·47, P for trend = 0·084; for blacks: HR 1·36; 95 % CI 1·04, 1·77, P for trend = 0·028). A high Na:K ratio was not significantly associated with stroke in whites (HR 1·29; 95 % CI 0·88, 1·90) or blacks (HR 1·39; 95 % CI 0·78, 2·48), partly because of the low number of stroke events. In the REGARDS study, a high Na:K ratio was associated with all-cause mortality and there was a suggestive association between the Na:K ratio and stroke. These data support the policies targeted at reduction of Na from the food supply and recommendations to increase K intake.

Abstract P351: Inflammation and Stroke Risk in the Reasons for Geographic and Racial Differences in Stroke (REGARDS) Study

Circulation ◽  
2014 ◽  
Vol 129 (suppl_1) ◽  
Author(s):  
Nancy S Jenny ◽  
Peter Callas ◽  
Neil A Zakai ◽  
Leslie McClure ◽  
Suzanne Judd ◽  
...  
Keyword(s):  
Risk Factors ◽  
Racial Differences ◽  
Stroke Risk ◽  
Proportional Hazards ◽  
Population Based ◽  
Cox Proportional Hazards ◽  
Stroke Patients ◽  
Stroke Risk Factors ◽  
Cox Proportional Hazards Models ◽  
Regards Study

Background: Levels of the pro-inflammatory cytokines interleukin (IL)-6 and IL-8 and the anti-inflammatory cytokine IL-10 are altered in acute stroke patients compared to controls. However, results for IL-10 are inconsistent (higher in stroke patients compared to controls in some studies and decreased in others) and very few studies have examined associations of these biomarkers with risk of incident stroke. Methods: We examined associations of baseline levels of IL-6, IL-8 and IL-10 with stroke risk factors and risk of incident stroke in 1,572 white and black men and women from the REGARDS Study; an observational cohort of 30,239 adults followed for 5 years. Among those without prebaseline stroke, stroke cases (n=592, 53% men, 59% white, mean age 70 years) were compared to a cohort random sample (n=980, 44% men, 58% white, mean age 65 years). We used Cox proportional hazards models to examine associations of biomarkers with incident stroke. Hazard ratios (HR; 95% confidence intervals) for highest compared to lowest quartile for each biomarker are presented. Results: Baseline IL-6 was significantly higher in incident stroke cases compared to the cohort sample (p<0.001) while IL-8 and IL-10 levels did not vary significantly (p>0.05 for both). Adjusting for age, sex and race, IL-6 was higher in blacks compared to whites and higher in current smokers compared to never/former smokers (all p≤0.01). IL-6 was inversely associated with physical activity, alcohol use and education (all p≤0.01). IL-8 and IL-10 did not vary significantly with the risk factors examined. Adjusting for age, sex and race, the HR for risk of incident stroke in those in the highest compared to lowest quartile of IL-6 was 2.4 (1.6-3.4). HRs for IL-8 and IL-10 were 1.5 (1.0-2.1) and 1.4 (1.0-1.9), respectively. Adjusting for Framingham stroke risk factors and history of coronary heart disease, only IL-6 remained significantly associated with stroke risk (HR 2.0; 1.3-3.2). HRs for IL-8 and IL-10 were 1.1 (0.7-1.6) and 1.2 (0.8-1.8), respectively. IL-6 remained significantly associated with stroke risk when C-reactive protein was added to the model (HR 1.7; 1.1-2.7). Associations did not differ by race. Conclusions: In this population-based sample of US black and white adults, IL-6, but not IL-8 or IL-10, was associated with stroke risk factors and risk of incident stroke. Further study is needed on the clinical utility of IL-6 measurement in stroke risk assessment.

Abstract P316: Prehypertension and Incident Acute Coronary Heart Disease in the REasons for Geographic and Racial Differences in Stroke (REGARDS) Study

Circulation ◽  
2013 ◽  
Vol 127 (suppl_12) ◽  
Author(s):  
Stephen P Glasser ◽  
Yulia Khodneva ◽  
Daniel Lackland ◽  
Ronald Prineas ◽  
Monika Safford
Keyword(s):  
Coronary Heart Disease ◽  
Heart Disease ◽  
Racial Differences ◽  
Proportional Hazards ◽  
Cox Proportional Hazards ◽  
Community Dwelling ◽  
Cox Proportional Hazards Models ◽  
Chd Risk ◽  
Regards Study ◽  
Chd Risk Factors

Objective: The independent prognostic value of prehypertension (preHTN) for incident coronary heart disease (CHD) remains unsettled. Using the REasons for Geographic And Racial Differences in Stroke (REGARDS) cohort study, we examined associations between preHTN and incident acute CHD and CVD death. Methods: REGARDS includes 30,239 black and white community-dwelling adults age 45 and older at baseline. Recruitment occurred from 2003-7, with baseline interviews and in-home data collection for physiologic measures. Follow-up is conducted by telephone every 6 months to detect events and deaths, which are adjudicated by experts. Systolic BP was categorized into <120 mmHg (n=4385), 120-129 mmHg (n=4000), 130-139 (n=2066), and hypertension was categorized into controlled (<140/90 mmHg on treatment) (n=8378), and uncontrolled (>140/90 mmHg) (n=5364). Incident acute CHD was defined as definite or probable myocardial infarction (MI) or acute CHD death. CVD death was defined as acute CHD, stroke, heart failure or other cardiovascular disease related. Cox proportional hazards models estimated the hazard ratios (HR) for incident CHD by BP categories, adjusting for sociodemographics and CHD risk factors. Results: The 23,393 participants free of CHD at baseline were followed for a median of 4.4 years. Mean age was 64.1, 58% were women and 42% were black. There was a significant interaction between sex and BP categories, therefore analyses were stratified by sex. There were 252 non-fatal and fatal acute CHD events among women and 407 among men. Among women, compared with SBP<120 mmHg, BP categories above SBP 120 mmHg were associated with incident CHD (adjusted HR for SBP120-129 mmHg=1.94 {95% CI 1.04-3.62]; SBP 130-139 mmHg=1.92 {0.95-3.87}; controlled HTN=2.16 {1.25-3.75}; uncontrolled HTN=3.25 {1.87-5.65}) in fully adjusted models. Among men, only uncontrolled HTN was associated with incident CHD (HR=1.55 {1.11-2.17}). Conclusion: In this sample, preHTN may be associated with incident CHD among women but not men.

Abstract P316: Multiple Vulnerabilities to Health Disparities and Incident Coronary Heart Disease in the Reasons for Geographic and Racial Differences in Stroke (REGARDS) Study

Circulation ◽  
2018 ◽  
Vol 137 (suppl_1) ◽  
Author(s):  
Monika M Safford ◽  
Laura Pinheiro ◽  
Madeline Sterling ◽  
Joshua Richman ◽  
Paul Muntner ◽  
...  
Keyword(s):  
Health Disparities ◽  
Racial Differences ◽  
Low Income ◽  
Proportional Hazards ◽  
Health Management ◽  
Cox Proportional Hazards ◽  
Southeastern Us ◽  
Cox Proportional Hazards Models ◽  
Increased Risk ◽  
Regards Study

Social determinants contribute to disparities in incident CHD but it is not known if they have an additive effect. We hypothesized that having more socially determined vulnerabilities to health disparities is associated with increased risk of incident CHD in the REGARDS study, a large biracial prospective cohort with physiological and survey measures. Experts adjudicated incident fatal and nonfatal CHD over 10 years of follow-up. Vulnerabilities included black race, low education, low income, and Southeastern US residence. The risks for CHD outcomes associated with 1, 2, and 3+ vs 0 vulnerabilities were calculated with Cox proportional hazards models adjusted for medical conditions, functional status, health behaviors, and physiologic variables. Of the 19,645 participants free of CHD at baseline (mean age 64 years, 57% women), 16% had 0 vulnerabilities, 36% had 1, 29% had 2, and 18% had 3+. Increasing numbers of vulnerabilities were associated with higher incidence (Figure) and risk of CHD that attenuated somewhat after multivariable adjustment (Table). These findings may provide a method of risk stratification useful for population health management.

scholarly journals Electrocardiographic ST-T Abnormities Are Associated With Stroke Risk in the REGARDS Study

Stroke ◽  
2020 ◽  
Vol 51 (4) ◽  
pp. 1100-1106
Author(s):  
Mitsuaki Sawano ◽  
Ya Yuan ◽  
Shun Kohsaka ◽  
Taku Inohara ◽  
Takeki Suzuki ◽  
...  
Keyword(s):  
Ischemic Stroke ◽  
Racial Differences ◽  
Stroke Risk ◽  
Proportional Hazards ◽  
The United States ◽  
Incidence Rates ◽  
Cox Proportional Hazards ◽  
Hazard Ratio ◽  
Common Finding ◽  
Increased Risk

Background and Purpose— In previous studies, isolated nonspecific ST-segment and T-wave abnormalities (NSSTTAs), a common finding on ECGs, were associated with greater risk for incident coronary artery disease. Their association with incident stroke remains unclear. Methods— The REGARDS (Reasons for Geographic and Racial Differences in Stroke) study is a population-based, longitudinal study of 30 239 white and black adults enrolled from 2003 to 2007 in the United States. NSSTTAs were defined from baseline ECG using the standards of Minnesota ECG Classification (Minnesota codes 4-3, 4-4, 5-3, or 5-4). Participants with prior stroke, coronary heart disease, and major and minor ECG abnormalities other than NSSTTAs were excluded from analysis. Multivariable Cox proportional hazards regression was used to examine calculate hazard ratios of incident ischemic stroke by presence of baseline NSSTTAs. Results— Among 14 077 participants, 3111 (22.1%) had NSSTTAs at baseline. With a median of 9.6 years follow-up, 106 (3.4%) with NSSTTAs had ischemic stroke compared with 258 (2.4%) without NSSTTAs. The age-adjusted incidence rates (per 1000 person-years) of stroke were 2.93 in those with NSSTTAs and 2.19 in those without them. Adjusting for baseline age, sex, race, geographic location, and education level, isolated NSSTTAs were associated with a 32% higher risk of ischemic stroke (hazard ratio, 1.32 [95% CI, 1.05–1.67]). With additional adjustment for stroke risk factors, the risk of stroke was increased 27% (hazard ratio, 1.27 [95% CI, 1.00–1.62]) and did not differ by age, race, or sex. Conclusions— Presence of NSSTTAs in persons with an otherwise normal ECG was associated with a 27% increased risk of future ischemic stroke.

Abstract 90: Race, Ethnic, and Sex Disparities in Stroke Incidence in the Northern Manhattan Study

Stroke ◽  
2020 ◽  
Vol 51 (Suppl_1) ◽  
Author(s):  
Hannah Gardener ◽  
Ralph L Sacco ◽  
Tatjana Rundek ◽  
Consuelo Mora-McLaughlin ◽  
Ying Kuen Cheung ◽  
...  
Keyword(s):  
Incidence Rate ◽  
Low Socioeconomic Status ◽  
Stroke Risk ◽  
Proportional Hazards ◽  
Population Based ◽  
Incidence Rates ◽  
Cox Proportional Hazards ◽  
Stroke Incidence ◽  
Cox Proportional Hazards Models ◽  
Hazard Ratios

Background: An excess incidence of strokes among blacks vs whites has been shown previously, but data on disparities related to Hispanic ethnicity remains limited. This study examines race, ethnic, and sex differences in stroke incidence in the multi-ethnic, yet largely Caribbean Hispanic, Northern Manhattan Study (NOMAS). Methods: The study population included participants in the prospective population-based NOMAS, followed for a mean of 13±7 years. Cox proportional hazards models were constructed to estimate the hazard ratios and 95% confidence intervals (HR, 95%CI) for the association between race/ethnicity and sex with confirmed incident stroke of any subtype and ischemic stroke, stratified by age and adjusting for sociodemographics and vascular risk factors. Results: Among 3,298 participants (mean baseline age 69±10, 37% men, 24% black, 21% white, 52% Hispanic), 477 incident strokes accrued (394 ischemic, 43 ICH, 9 SAH). The most common ischemic subtype was cardioembolic, followed by lacunar infarcts, then cryptogenic. The greatest incidence rate was observed in blacks (13/1000 person-years [PY]), followed by Hispanics (11/1000 PY), and lowest in whites (8/1000 PY), and this order was observed for crude incidence rates until age 75. By age 85 the greatest incidence rate was in Hispanics. Blacks had an increased stroke risk vs whites overall in fully adjusted models (HR=1.37, 95% CI=1.02-1.84), and stratified analyses showed that this disparity was driven by women age ≥70 (HR=1.69, 1.05-2.73). The increased rate of stroke observed for Hispanics (age/sex-adjusted HR=1.50, 1.15-1.94) was largely explained by education and insurance status (a proxy for socieoeconomic status; HR after further adjusting for these variables=1.15, 0.84-1.58), but remained significant for women age ≥70. Men had an increased rate of stroke compared to women (fully adjusted HR=1.48, 1.21-1.81). Conclusions: This study provides novel data regarding the increased stroke risk among Caribbean Hispanics. Results highlight the need to create culturally-tailored campaigns to reach blacks and Hispanic populations to reduce race/ethnic stroke disparities, and support the important role of low socioeconomic status in driving an elevated risk among Caribbean Hispanics.

Abstract TP159: Risk of Ischemic Stroke in Patients with Atrial Flutter

Stroke ◽  
2017 ◽  
Vol 48 (suppl_1) ◽  
Author(s):  
Mais Al-Kawaz ◽  
Setareh Salehi Omran ◽  
Neal S Parikh ◽  
Mitchell S Elkind ◽  
Elsayed Z Soliman ◽  
...  
Keyword(s):  
Risk Factors ◽  
Ischemic Stroke ◽  
Lower Risk ◽  
Stroke Risk ◽  
Proportional Hazards ◽  
Cox Proportional Hazards ◽  
Administrative Claims ◽  
Primary Analysis ◽  
Stroke Incidence ◽  
The Difference

Introduction: Guidelines advise anticoagulation for patients with both atrial fibrillation (AF) and flutter (AFL). However, the risk of stroke associated with these two conditions has not been robustly compared. Methods: Using inpatient and outpatient Medicare administrative claims data from 2008-2014 for a 5% sample of all beneficiaries ≥66 years of age, we identified all patients diagnosed with AFL or AF. Patients with prior stroke were excluded. The primary outcome was ischemic stroke. Predictors and the outcome were ascertained by validated ICD-9-CM diagnosis codes. Patients were censored at the time of ischemic stroke, death, or last available follow-up. In the primary analysis, patients with AFL were censored upon diagnosis of AF. Survival statistics were used to compare stroke incidence in patients with AF versus AFL. We used Cox proportional hazards analysis to compare the associations of AFL and AF with ischemic stroke after adjustment for demographics and risk factors. In a secondary analysis, patients with AFL were not censored upon diagnosis of AF because the natural history of AFL frequently features the development of AF. Results: We identified 16,441 patients with AFL and 338,726 with AF. Patients with AFL were less often female (42.4% versus 53.0%), but other baseline characteristics, including mean CHA 2 DS 2 -VASc scores (3.9), were similar between groups. Over 2.4 (±2.0) years, 16,451 ischemic strokes were identified. The annual incidence of ischemic stroke in patients with AFL was 0.60% (95% confidence interval [CI], 0.48-0.75%), whereas it was 2.00% (95% CI, 1.96-2.02%) in patients with AF. After adjustment for demographics and vascular risk factors, AFL was associated with a lower risk of ischemic stroke than AF (hazard ratio [HR], 0.30; 95% CI, 0.24-0.37). Within 1 year, 64.9% (95% CI, 64.1-65.6%) of patients with AFL received a diagnosis of AF. The difference between stroke risk in AFL compared to AF was attenuated (HR, 0.85; 95% CI, 0.79-0.92) when patients with AFL were not censored upon diagnosis of AF. Conclusions: Patients with AFL may face a lower risk of ischemic stroke than patients with AF. However, AF often develops in those with AFL, and taking this into account, the difference in stroke risk between the two conditions grows smaller.

Abstract 16923: Healthy Lifestyle is Inversely Associated With All-Cause Mortality Irrespective of Medication Burden

Circulation ◽  
2020 ◽  
Vol 142 (Suppl_3) ◽  
Author(s):  
Neil Kelly ◽  
Orysya Soroka ◽  
Chukwuma Onyebeke ◽  
Laura Pinheiro ◽  
Samprit Banerjee ◽  
...  
Keyword(s):  
Racial Differences ◽  
Proportional Hazards ◽  
Sedentary Lifestyle ◽  
Healthy Lifestyle ◽  
Cox Proportional Hazards ◽  
Healthy Behaviors ◽  
Cox Proportional Hazards Models ◽  
All Cause Mortality ◽  
High Adherence ◽  
Regards Study

Introduction: The benefits of a healthy lifestyle in the context of a high disease and medication burden are not clear. Hypothesis: Healthy lifestyle is inversely associated with all-cause mortality among adults with high medication burden. Methods: We examined participants from the Reasons for Geographic and Racial Differences in Stroke (REGARDS) study. Exposure variables were 4 healthy behaviors: adherence to a Mediterranean diet, physical activity, smoking abstinence, and sedentary lifestyle avoidance (low TV time). Each behavior was scored from 0-2, where 0 indicated low adherence and 2 indicated high adherence. We also examined a cumulative Health Behavior Score (HBS) based on the sum of individual behavior scores (range 0-8). The main outcome was all-cause mortality. To examine the association between each behavior and mortality, we estimated Cox proportional hazards models for each medication burden stratum (no polypharmacy: 0-4 medications at baseline; polypharmacy: 5-9; hyperpolypharmacy: ≥ 10), adjusting for socio-demographics, health status, comorbid conditions, and medication adherence. Results: Among 20,417 participants (9.8 ± 3.8 years followup), mean age was 64.8 ± 9.2 years, and 56% were women. At baseline, 44% had no polypharmacy, 39% had polypharmacy, and 17% had hyperpolypharmacy. Mortality increased with increasing medication burden (no polypharmacy: 19.1%; polypharmacy: 29.7%; hyperpolypharmacy: 41.3%). The highest score for each behavior was inversely associated with all-cause mortality in all 3 strata. The highest HBS for each stratum conferred substantial benefit (no polypharmacy: HR 0.52 (95% CI 0.45-0.61); polypharmacy: HR 0.55 (95% CI 0.49-0.63); hyperpolypharmacy HR 0.69 (95% CI 0.58-0.82)) (Table). Conclusions: Healthy lifestyle was inversely associated with all-cause mortality irrespective of medication burden, supporting the value of healthy lifestyle counseling even among adults with high medication burden.

scholarly journals Risk of Ischemic Stroke Increases Over the Spectrum of Metabolic Syndrome Severity

Stroke ◽  
2020 ◽  
Vol 51 (8) ◽  
pp. 2548-2552 ◽  
Author(s):  
Mark D. DeBoer ◽  
Stephanie L. Filipp ◽  
Mario Sims ◽  
Solomon K. Musani ◽  
Matthew J. Gurka
Keyword(s):  
Metabolic Syndrome ◽  
Ischemic Stroke ◽  
Stroke Risk ◽  
Proportional Hazards ◽  
Lifestyle Modification ◽  
Cox Proportional Hazards ◽  
Hazard Ratio ◽  
The Metabolic Syndrome ◽  
Cox Proportional Hazards Models ◽  
Ischemic Stroke Risk

Background and Purpose: Ischemic stroke is associated with the metabolic syndrome (MetS) as diagnosed using dichotomous criteria; however, these criteria exhibit racial/ethnic discrepancies. Our goal was to assess whether ischemic stroke risk extended over the spectrum of worsening MetS severity using a sex- and race/ethnicity-specific MetS-severity Z score. Methods: We used Cox-proportional hazards models to assess the relationship between baseline MetS- Z score and incident ischemic stroke among participants of the Atherosclerosis Risk in Communities study and Jackson Heart Study who were free from diabetes, coronary heart disease or stroke at baseline, evaluating 13 141 white and black individuals with mean follow-up of 18.6 years. Results: We found that risk of ischemic stroke increased consistently with MetS severity, with a hazard ratio of 1.75 (95% CI, 1.35–2.27) for those >75th percentile compared to those <25th percentile. This risk was highest for white females (hazard ratio, 2.63 [CI, 1.70–4.07]) though without significant interaction by sex and race. Relationships between stroke and all the individual components of MetS were only noted for white females, though again without sex-race interactions. Hazard ratio’s for systolic blood pressure and stroke were significant among all sex/racial subgroups. Conclusions: Ischemic stroke risk increased over the spectrum of MetS severity in the absence of baseline diabetes mellitus, further implicating potential etiologic risks from processes underlying MetS. Individuals with elevated MetS severity should be counselled toward lifestyle modification to lower ischemic stroke risk.

Abstract 187: Electrocardiographic Heart Rate-corrected Qt Interval And Risk Of Stroke In The REasons For Geographic And Racial Differences In Stroke (REGARDS) Study

Stroke ◽  
2012 ◽  
Vol 43 (suppl_1) ◽  
Author(s):  
Elsayed Z Soliman ◽  
George Howard ◽  
George Howard ◽  
Mary Cushman ◽  
Brett Kissela ◽  
...  
Keyword(s):  
Heart Rate ◽  
Racial Differences ◽  
Qt Interval ◽  
Proportional Hazards ◽  
Left Ventricular ◽  
Cox Proportional Hazards ◽  
Corrected Qt Interval ◽  
Cardiovascular Morbidity And Mortality ◽  
Increased Risk ◽  
Regards Study

Background: Prolongation of heart rate-corrected QT interval (QTc) is a well established predictor of cardiovascular morbidity and mortality. Little is known, however, about the relationship between this simple electrocardiographic (ECG) marker and risk of stroke. Methods: A total of 27,411 participants aged > 45 years without prior stroke from the REasons for Geographic and Racial Differences in Stroke (REGARDS) study were included in this analysis. QTc was calculated using Framingham formula (QTcFram). Stroke cases were identified and adjudicated during an up to 7 years of follow-up (median 2.7 years). Cox proportional hazards analysis was used to estimate the hazard ratios for incident stroke associated with prolonged QTcFram interval (vs. normal) and per 1 standard deviation (SD) increase, separately, in a series of incremental models. Results: The risk of incident stroke in the study participants with baseline prolonged QTcFram was almost 3 times the risk in those with normal QTcFram [HR (95% CI): 2.88 (2.12, 3.92), p<0.0001]. After adjustment for age, race, sex, antihypertensive medication use, systolic blood pressure, current smoking, diabetes, left ventricular hypertrophy, atrial fibrillation, prior cardiovascular disease, QRS duration, warfarin use, and QT-prolonging drugs (full model), the risk of stroke remained significantly high [HR (95% CI): 1.67 (1.16, 2.41), p=0.0060)], and was consistent across several subgroups of REGARDS participants. When the risk of stroke was estimated per 1 SD increase in QTcFram, a 24% increased risk was observed [HR (95% CI): 1.24 (1.16, 1.33), p<0.0001)]. This risk remained significant in the fully adjusted model [HR (95% CI): 1.12 (1.03, 1.21), p=0.0055]. Similar results were obtained when other QTc correction formulas including Hodge’s, Bazett’s and Fridericia’s were used. Conclusions: QTc prolongation is associated with a significantly increased risk of incident stroke independently from known stroke risk factors. In light of our results, examining the risk of stroke associated with QT-prolonging drugs may be warranted.

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