Stroke incidence and survival among middle-aged adults: 9-year follow-up of the Atherosclerosis Risk in Communities (ARIC) cohort

Stroke Incidence and Survival in American Indians, Blacks, and Whites: The Strong Heart Study and Atherosclerosis Risk in Communities Study

Background

American Indians (AIs) have high stroke morbidity and mortality. We compared stroke incidence and mortality in AIs, blacks, and whites.

Methods and Results

Pooled data from 2 cardiovascular disease cohort studies included 3182 AIs from the SHS (Strong Heart Study), aged 45 to 74 years at baseline (1988–1990) and 3765 blacks and 10 413 whites from the ARIC (Atherosclerosis Risk in Communities) Study, aged 45 to 64 years at baseline (1987–1989). Stroke surveillance was based on self‐report, hospital records, and death certificates. We estimated hazard ratios for incident stroke (ischemic and hemorrhagic combined) through 2008, stratified by sex and birth‐year tertile, and relative risk for poststroke mortality. Incident strokes numbered 282 for AIs, 416 for blacks, and 613 for whites. For women and men, stroke incidence among AIs was similar to or lower than blacks and higher than whites. Covariate adjustment resulted in lower hazard ratios for most comparisons, but results for these models were not always statistically significant. After covariate adjustment, AI women and men had higher 30‐day poststroke mortality than blacks (relative risk=2.1 [95% CI=1.0, 3.2] and 2.2 [95% CI=1.3, 3.1], respectively), and whites (relative risk=1.6 [95% CI=0.8, 2.5] and 1.7 [95% CI=1.1, 2.4]), and higher 1‐year mortality (relative risk range=1.3–1.5 for all comparisons).

Conclusions

Stroke incidence in AIs was lower than for blacks and higher than for whites; differences were larger for blacks and smaller for whites after covariate adjustment. Poststroke mortality was higher in AIs than blacks and whites.

Association of Undifferentiated Dyspnea in Late Life With Cardiovascular and Noncardiovascular Dysfunction: A Cross-sectional Analysis From the ARIC Study

Importance

Undifferentiated dyspnea is common in late life, but the relative contribution of subclinical cardiac dysfunction is unknown. Impairments in cardiac structure and function may be characteristics of undifferentiated dyspnea in elderly people, providing potential insights into occult heart failure (HF).

Objective

To quantify the association of undifferentiated dyspnea with cardiac dysfunction after accounting for other potential contributors.

Design, Setting, and Participants

This cross-sectional study used data from Atherosclerosis Risk in Communities study participants 65 years and older who attended the fifth study visit (from 2011 to 2013) and had not been diagnosed with HF, chronic obstructive pulmonary disease, morbid obesity, or severe kidney disease. Analyses were conducted from October 2017 to June 2018.

Exposures

Dyspnea measured using the modified Medical Research Council scale, with a score less than 2 classified as none to mild and a score of 2 or more classified as moderate to severe.

Main Outcomes and Measures

Using multivariable logistic regression, the association of undifferentiated dyspnea was defined using cardiac structure, systolic and diastolic function, pulmonary pressure (echocardiography), pulmonary function (spirometry), glomerular filtration rate, hemoglobin, body mass index, depression, and physical performance. The population-attributable risk was calculated for each dysfunction metric.

Results

Among 4342 participants (mean [SD] age, 75.9 [5.0] years; 2533 [58.3%] women), 1173 (27.0%) had undifferentiated dyspnea. Moderate to severe dyspnea was present in 574 participants (13.2%) and was associated with left ventricular (LV) hypertrophy (odds ratio [OR], 1.53; 95% CI, 1.25-1.87; P < .001) and LV diastolic (OR, 1.46; 95% CI, 1.20-1.78; P < .001) and systolic (OR, 1.28; 95% CI, 1.05-1.56; P = .02) dysfunction. Moderate to severe dyspnea was also associated with obstructive (OR, 1.59; 95% CI, 1.28-1.99; P < .001) and restrictive (OR, 2.56; 95% CI, 1.99-3.27; P < .001) findings on spirometry, renal impairment (OR, 1.32; 95% CI, 1.08-1.61; P = .01), anemia (OR, 1.72; 95% CI, 1.39-2.12; P < .001), lower (OR, 2.77; 95% CI, 2.18-3.51; P < .001) and upper (OR, 1.82; 95% CI, 1.49-2.23; P < .001) extremity weakness, depression (OR, 3.01; 95% CI, 2.24-4.25; P < .001), and obesity (OR, 2.35; 95% CI, 1.95-2.83; P < .001). After accounting for these, moderate to severe dyspnea was associated with LV hypertrophy (OR, 1.30; 95% CI, 1.01-1.67; P = .04) and was not associated with systolic or diastolic function. In contrast, in the fully adjusted model, other organ system measures were associated with dyspnea, except for glomerular filtration rate and grip strength. The population-attributable risk of dyspnea associated with obesity alone was 22.6% compared with 5.8% for LV hypertrophy.

Conclusions and Relevance

Undifferentiated dyspnea is multifactorial in older adults, and this study showed an association with obesity. When accounting for other relevant organ systems, cardiovascular function poorly discriminated those with vs those without dyspnea. Therefore, dyspnea should not be assumed to represent occult HF in this population.

Temporal trends in validated ischaemic stroke hospitalizations in the USA

BACKGROUND

Accurate assessment of the burden of stroke, a major cause of disability and death, is crucial. We aimed to estimate rates of validated ischaemic stroke hospitalizations in the USA during 1998-2011.

METHODS

We used the Atherosclerosis Risk in Communities (ARIC) study cohort's adjudicated stroke data for participants aged ≥55 years, to construct validation models for each International Classification of Diseases (ICD)-code group and patient covariates. These models were applied to the Nationwide Inpatient Sample (NIS) data to estimate the probability of validated ischaemic stroke for each eligible hospitalization. Rates and trends in NIS using ICD codes vs estimates of validated ischaemic stroke were compared.

RESULTS

After applying validation models, the estimated annual average rate of validated ischaemic stroke hospitalizations in the USA during 1998-2011 was 3.37 [95% confidence interval (CI): 3.31, 3.43) per 1000 person-years. Validated rates declined during 1998-2011 from 4.7/1000 to 2.9/1000; however, the decline was limited to 1998-2007, with no further decline subsequently through 2011. Validation models showed that the false-positive (∼23% of strokes) and false-negative rates of ICD-9-CM codes in primary position for ischaemic stroke approximately cancel. Therefore, estimates of ischaemic stroke hospitalizations did not substantially change after applying validation models.

CONCLUSIONS

Overall, ischaemic stroke hospitalization rates in the USA have declined during 1998-2007, but no further decline was observed from 2007 to 2011. Validated ischaemic stroke hospitalizations estimates were similar to published estimates of hospitalizations with ischaemic stroke ICD codes in primary position. Validation of national discharge data using prospective chart review data is important to estimate the accuracy of reported burden of stroke.

Association of Antidepressant Medication Type With the Incidence of Cardiovascular Disease in the ARIC Study

Background

The association of antidepressant medication type with the risk of cardiovascular disease (CVD) is unclear. We hypothesized that selective serotonin reuptake inhibitors (SSRIs) are associated with lower risks of CVD events relative to tricyclics and other non‐SSRI antidepressants.

Methods and Results

We studied 2027 participants from the ARIC (Atherosclerosis Risk in Communities) study (mean age 63±10 years; 29% men; 78% white) treated with antidepressants at some time between 1987 and 2013. Antidepressant usage was confirmed by participants bringing pill bottles to study visits. CVD events in the study sample were identified, including atrial fibrillation, heart failure, myocardial infarction, and ischemic stroke. Hazard ratios were used to compare CVD events adjusted for sociodemographic and clinical risk factors in SSRIs users (47%) versus non‐SSRI users. Participants were followed from antidepressant initiation up to 2016 for a median of 13.5 years. We identified 332 atrial fibrillation, 365 heart failure, 174 myocardial infarction and 119 ischemic stroke events. CVD risk was similar for SSRIs and non‐SSRI antidepressant users (hazard ratio, 1.10; 95% CI, 0.86–1.41 for atrial fibrillation; hazard ratio, 0.98; 95% CI, 0.77–1.25 for heart failure; hazard ratio, 0.91; 95% CI, 0.64–1.29 for myocardial infarction; and hazard ratio, 1.07; 95% CI, 0.70–1.63 for ischemic stroke).

Conclusions

SSRI use was not associated with reduced risk of incident CVD compared with non‐SSRI antidepressant use. These results do not provide evidence supporting the use of SSRIs compared with tricyclics and other non‐SSRI antidepressants in relation to CVD risk.

The Association Between Parity and Subsequent Cardiovascular Disease in Women: The Atherosclerosis Risk in Communities Study

Background: Previous studies are inconclusive on the relationship between parity and cardiovascular disease (CVD), with few evaluating multiple cardiovascular outcomes. It is also unclear if any relationship between parity and CVD is independent of breastfeeding. We examined the associations between parity and cardiovascular outcomes, including breastfeeding adjustment. Materials and Methods: Data were from 8,583 White and African American women, 45-64 years of age, in the Atherosclerosis Risk in Communities Study. Coronary heart disease (CHD), myocardial infarction (MI), heart failure, and strokes were ascertained from 1987 to 2016 by annual interviews and hospital surveillance. Parity and breastfeeding were self-reported. Cox proportional hazards regression estimated hazard ratios (HR) for the association between parity and cardiovascular outcomes, adjusting for baseline sociodemographic, clinical and lifestyle factors, and breastfeeding. Results: Women reported no pregnancies (6.0%), or having 0 (1.6%), 1-2 (36.2%), 3-4 (36.4%), or 5+ (19.7%) live births. During 30 years follow-up, there were 1,352 CHDs, 843 MIs, 750 strokes, and 1,618 heart failure events. Compared with women with 1-2 prior births, those with prior pregnancies and no live births had greater incident CHD (HR = 1.64, 95% confidence interval 1.14-2.42) and heart failure risk (1.46, 1.04-2.05), after adjustment for baseline characteristics. Women with 5+ births had greater risk of CHD (1.29, 1.10-1.52) and hospitalized MI (1.38, 1.13-1.69), after adjustment for baseline characteristics and breastfeeding. Conclusions: In a diverse U.S. cohort, a history of 5+ live births is associated with CHD risk, specifically, MI, independent of breastfeeding. Having a prior pregnancy and no live birth is associated with greater CHD and heart failure risk.

Plasma Metabolites Associated with Brain MRI Measures of Neurodegeneration in Older Adults in the Atherosclerosis Risk in Communities⁻Neurocognitive Study (ARIC-NCS)

Background: Plasma metabolites are associated with cognitive and physical function in the elderly. Because cerebral small vessel disease (SVD) and neurodegeneration are common causes of cognitive and physical function decline, the primary objective of this study was to investigate the associations of six plasma metabolites (two plasma phosphatidylcholines [PCs]: PC aa C36:5 and PC aa 36:6 and four sphingomyelins [SMs]: SM C26:0, SM [OH] C22:1, SM [OH] C22:2, SM [OH] C24:1) with magnetic resonance imaging (MRI) features of cerebral SVD and neurodegeneration in older adults. Methods: This study included 238 older adults in the Atherosclerosis Risk in Communities study at the fifth exam. Multiple linear regression was used to assess the association of each metabolite (log-transformed) in separate models with MRI measures except lacunar infarcts, for which binary logistic regression was used. Results: Higher concentrations of plasma PC aa C36:5 had adverse associations with MRI features of cerebral SVD (odds ratio of 1.69 [95% confidence interval: 1.01, 2.83] with lacunar infarct, and beta of 0.16 log [cm3] [0.02, 0.30] with log [White Matter Hyperintensities (WMH) volume]) while higher concentrations of 3 plasma SM (OH)s were associated with higher total brain volume (beta of 12.0 cm3 [5.5, 18.6], 11.8 cm3 [5.0, 18.6], and 7.3 cm3 [1.2, 13.5] for SM [OH] C22:1, SM [OH] C22:2, and SM [OH] C24:1, respectively). Conclusions: This study identified associations between certain plasma metabolites and brain MRI measures of SVD and neurodegeneration in older adults, particularly higher SM (OH) concentrations with higher total brain volume.

Racial Variation in Stroke Risk Among Women by Stroke Risk Factors

Background and Purpose- In the United States, black Americans exhibit a greater risk of stroke and burden of stroke risk factors than whites; however, it is unclear whether these stroke risk factors influence stroke risk differently across racial groups. Methods- In total, 126 018 participants of the Women's Health Initiative (11 389 black and 114 629 white women), free of stroke and coronary heart disease at baseline (1994-1998), were followed through 2010. Participants completed baseline clinical exams with standardized measurements of blood pressure and anthropometrics, medication inventory and self-reported questionnaires on sociodemographics, behaviors/lifestyle, and medical history. Incident total, ischemic and hemorrhagic strokes were updated annually through questionnaires with medical record confirmation. Rate differences (per 100 000 person-years) and hazard ratios (HR) based on multivariable Cox models and were estimated. Results- Over a median of 13 years, 4344 stroke events were observed. Absolute incidence rates were higher in black than white women in each age group. In age-adjusted analyses, the risk of stroke was significantly higher among black compared with white women (HR=1.47, 95% CI, 1.33-1.63); adjustment for stroke risk factors, which may be on the causal pathway, attenuated the estimate. Racial disparities were greatest among women 50 to <60 years (HR=3.48; 95% CI, 2.31-5.26; rate difference =99) and diminished with increasing age (60 to <70 HR=1.80; 95% CI, 1.50-2.16; rate difference =107; ≥70 years: HR=1.26; 95% CI, 1.10-1.43; rate difference =87; Pinteraction <0.001). Black women 50 to <60 years remained at significantly higher risk than white women after adjustment for stroke risk factors (HR=1.76; 95% CI, 1.09-2.83). Conclusions- There was a moderately greater risk of total stroke among black compared with white women; however, racial disparities were greatest among women aged 50 to <60 years. Interventions targeted at younger black women may provide the greatest benefit in reducing disparities.

Clinical characteristics and risk score for poor clinical outcome of acute ischemic stroke patients treated with intravenous thrombolysis therapy

BACKGROUND

Tissue plasminogen activator (t-PA) is an effective therapy for acute ischemic stroke, but some patients still have poor clinical outcome. In this study, we investigated clinical characteristics of stroke patients and determined predictors for poor clinical outcome in response to t-PA treatment.

METHODS

Clinical data from 247 patients were retrospectively reviewed. Clinical parameters that were associated with survival of patients were analyzed. Areas under receiver operating characteristic curves (ROC) were used to determine the feasibility of using various combinations of the clinical parameters to predict poor clinical response. The clinical outcome was defined according to the changes in Modified Rankin Scale.

RESULTS

Overall, 145 patients had improved/complete recovery, 73 had no change, and 29 had worsening conditions or died during the in-clinic period. A univariate analysis showed that baseline characteristics including age, CRP, blood glucose level, systolic blood pressure, and admission NIHSS were significantly different (p < 0.05) among patients with different clinical outcome. A further multivariate analysis was then performed. Variables associated with poor clinical outcome (worsening/death) (p < 0.1) were included in the logistic regression model. Four parameters were retained in the model: Age, CRP, Blood glucose level, and Systolic blood pressure (ACBS). To allow a convenient usage of the ACBS classifier, the parameters were put into a scoring system, and the score at 7.7 was chosen as a cut-off. The ROC curve of this ACBS classifier has an area under the curve (AUC) of 0.7788, higher than other individual parameters. The ACBS classifier provided enhanced sensitivity of 69.2% and specificity of 74.3%.

CONCLUSION

The ACBS classifier provided a satisfactory power in estimating the patients' clinical outcome. After further validating, the classifier may provide important information to clinicians for making clinical decisions.

A prospective study of serum metabolites and risk of ischemic stroke

OBJECTIVE

To identify promising blood-based biomarkers and novel etiologic pathways of disease risk, we applied an untargeted serum metabolomics profiling in a community-based prospective study of ischemic stroke (IS).

METHODS

In 3,904 men and women from the Atherosclerosis Risk In Communities study, Cox proportional hazard models were used to estimate the association of incident IS with the standardized level of 245 fasting serum metabolites individually, adjusting for age, sex, race, field center, batch, diabetes, hypertension, current smoking status, body mass index, and estimated glomerular filtration rate. Validation of results was carried out in an independent sample of 114 IS cases and 112 healthy controls.

RESULTS

Serum levels of 2 long-chain dicarboxylic acids, tetradecanedioate and hexadecanedioate, were strongly correlated (r = 0.88) and were associated with incident IS after adjusting for covariates (hazard ratio [95% confidence interval (CI)] 1.11 [1.06-1.16] and 1.12 [1.07-1.17], respectively; p < 0.0001). Analyses by IS subtypes suggested that these associations were specific to cardioembolic stroke (CES). Associations of tetradecanedioate and hexadecanedioate with IS were independently confirmed (odds ratio [95% CI] 1.76 [1.21; 2.56] and 1.60 [1.11; 2.32], respectively).

CONCLUSION

Two serum long-chain dicarboxylic acids, metabolic products of ω-oxidation of fatty acids, were associated with IS and CES independently of known risk factors. Pathways related to intracellular hexadecanedioate synthesis or those involved in its clearance from the circulation may mediate IS risk. These results highlight the potential of metabolomics to discover novel circulating biomarkers for stroke and to unravel novel pathways for IS and its subtypes.

Why are acute ischemic stroke patients not receiving thrombolysis in a telestroke network?

OBJECTIVE

The purpose of this study was to determine reasons for not giving intravenous tissue plasminogen activator to eligible patients with acute ischemic stroke in a telestroke network.

METHODS

We performed a retrospective analysis of prospectively collected data of patients who were seen as a telestroke consultation during 2015 and 2016 with the Arkansas Stroke Assistance through Virtual Emergency Support programme for possible acute ischemic stroke.

RESULTS

Total consultations seen were 809 in 2015 and 744 in 2016, out of which 238 patients in 2015 and 247 patients in 2016 received intravenous tissue plasminogen activator. In 2015 and 2016, out of the remaining 571 and 497 patients, 294 and 200 patients respectively were thought to be cases of acute stroke based on clinical evaluation. The most common reasons for not being treated in 2015 and 2016, respectively, were; (a) minimal deficits in 42.17% and 49.5% cases, (b) falling out of the 4.5-hour time window in 22.44% and 22% cases, (c) patient/next of kin refusal in 18.02% and 16.5% cases. Less common reasons included limited functional status, abnormal labs (thrombocytopenia, elevated international normalised ratio (INR)/prothrombin time (PT)/partial thromboplastin time (PTT), hypo or hyperglycemia etc), recent surgery and symptoms being too severe etc.

CONCLUSION

'Minimal deficits' and 'out of time window' continue to be the major causes for not receiving thrombolysis during acute ischemic stroke in both traditional and telestroke systems. Patient/next of kin refusal was high in our telestroke system when compared to traditional practices. Considering the increasing utility of telestroke this needs to be further looked into, along with the ways to address it.

Death after diagnosis of noncommunicable disease comorbid conditions, stratified by injection drug use

OBJECTIVE

Describe all-cause mortality associated with history of injection drug use (IDU) after a validated diagnosis of four noncommunicable disease (NCD) diagnoses: end-stage liver disease (ESLD); end-stage renal disease (ESRD); cancer; or myocardial infarction (MI) or stroke.

DESIGN

We followed four cohorts of persons in continuity HIV care in the Johns Hopkins HIV Clinic with a validated diagnosis of ESLD (n = 67), ESRD (n = 187), cancer (n = 424), and MI or stroke (n = 213) from 1996 through approximately 2014.

METHODS

Crude and adjusted Cox proportional hazards models to estimate hazard ratios for death after a validated diagnosis of one of four NCD diagnoses associated with history of IDU as an HIV acquisition risk factor.

RESULTS

History of IDU was not associated with death after ESRD (adjusted hazard ratio 0.98, 95% confidence interval (CI) 0.57-1.68). Associations between history of IDU and death after ESLD and MI or stroke were weak, imprecise and not statistically significant (hazard ratio 1.17, 95% CI 0.63-2.19; hazard ratio 1.21, 95% CI 0.80-1.83). History of IDU was not associated with death after cancer in the first 6 months, but subsequently, the adjusted hazard ratio was 2.03 (95% CI 1.26-3.27).

CONCLUSION

Persons with a history of injection drug use and non-IDU had strikingly similar risk and hazard of mortality after several major NCD diagnoses. Mortality after cancer diagnosis in this cohort was higher for persons with a history of IDU than those without; this may be because of being diagnosed with a different mix of specific sites and stages of cancers.

Migraine Age of Onset and Association With Ischemic Stroke in Late Life: 20 Years Follow-Up in ARIC

BACKGROUND AND PURPOSE

To evaluate the association between cumulative exposure to migraine and incidence of ischemic stroke in the Atherosclerosis Risk in Communities (ARIC) study.

METHODS

In this ongoing, prospective longitudinal community-based cohort, participants were interviewed to ascertain migraine history at the third visit (1993-1995), followed for ischemic stroke incidence over 20 years. We performed a post hoc analysis to evaluate the association between the age of migraine onset and ischemic stroke.

RESULTS

We identified 447 migraineurs with aura (MA) and 1128 migraineurs without aura (MO) among 11,592 black and white participants. There was an association between the age of MA onset ≥50 years old (average duration = 4.75 years) and ischemic stroke when compared to no headache group (multivariable adjusted HR = 2.17, 95% CI [1.39-3.39], P < .001). MA onset <50 years old (average duration = 28.17 years) was not associated with stroke (multivariable adjusted HR = 1.31, 95% CI [0.86-2.02], P = .212). These results were consistent with our logistic regression model. MO was not associated with increased stroke regardless of the age of onset. The absolute risk for stroke in migraine with aura is 37/447 (8.27%) and migraine without aura is 48/1128 (4.25%).

CONCLUSION

As compared to the no headache participants, increased stroke risk in late life was observed in participants with late onset of MA. In this cohort, longer cumulative exposure to migraine with visual aura, as would be expected with early onset of migraine, was not associated with increased risk of ischemic stroke in late life. This study underscores the importance of the age of onset of MA in assessing stroke risk in older migraineurs.

Refining Prediction of Atrial Fibrillation-Related Stroke Using the P2-CHA2DS2-VASc Score

BACKGROUND

In people with atrial fibrillation (AF), periods of sinus rhythm present an opportunity to detect prothrombotic atrial remodeling through measurement of P-wave indices (PWIs)-prolonged P-wave duration, abnormal P-wave axis, advanced interatrial block, and abnormal P-wave terminal force in lead V1. We hypothesized that the addition of PWIs to the CHA2DS2-VASc score would improve its ability to predict AF-related ischemic stroke.

METHODS

We included 2229 participants from the ARIC study (Atherosclerosis Risk in Communities) and 700 participants from MESA (Multi-Ethnic Study of Atherosclerosis) with incident AF who were not on anticoagulants within 1 year of AF diagnosis. PWIs were obtained from study visit ECGs before development of AF. AF was ascertained using study visit ECGs and hospital records. Ischemic stroke cases were based on physician adjudication of hospital records. We used Cox proportional hazards models to estimate hazard ratios and 95% CIs of PWIs for ischemic stroke. Improvement in 1-year stroke prediction was assessed by C-statistic, categorical net reclassification improvement, and relative integrated discrimination improvement.

RESULTS

Abnormal P-wave axis was the only PWI associated with increased ischemic stroke risk (hazard ratio, 1.84; 95% CI, 1.33-2.55) independent of CHA2DS2-VASc variables, and that resulted in meaningful improvement in stroke prediction. The β estimate was approximately twice that of the CHA2DS2-VASc variables, and thus abnormal P-wave axis was assigned 2 points to create the P2-CHA2DS2-VASc score. This improved the C-statistic (95% CI) from 0.60 (0.51-0.69) to 0.67 (0.60-0.75) in ARIC and 0.68 (0.52-0.84) to 0.75 (0.60-0.91) in MESA (validation cohort). In ARIC and MESA, the categorical net reclassification improvements (95% CI) were 0.25 (0.13-0.39) and 0.51 (0.18-0.86), respectively, and the relative integrated discrimination improvement (95% CI) were 1.19 (0.96-1.44) and 0.82 (0.36-1.39), respectively.

CONCLUSIONS

Abnormal P-wave axis-an ECG correlate of left atrial abnormality- improves ischemic stroke prediction in AF. Compared with CHA2DS2-VASc, the P2-CHA2DS2-VASc is a better prediction tool for AF-related ischemic stroke.

The burden of stroke in China: Results from a nationwide population-based epidemiological survey

Stroke is a serious threat to human health that often leads to severe complications, and currently ranks first as leading cause of death in China. However, reliable data on stroke burden in China in the 21st century are lacking. We used the data from NESS-China (National Epidemiological Survey of Stroke in China) for assessing the adverse health effects of stroke in Chinese population. We carried out inter-regional comparative study in order to obtain regular burden related characteristics of stroke in China, as measured by YLLs (years of life lost due to premature mortality), YLDs (years lived with disability) and DALYs (disability adjusted life years). Amongst the nationwide population of 596,536 individuals of all ages in 2013, the YLLs for stroke was 1748, the YLDs was 262, and the DALYs was 2010(per 100,000). The gender subtype analysis of DALYs was 2171(male) and 1848(female). The YLLs, YLDs and DALYs in rural areas were higher compared to urban areas. Among the 18 age groups, the highest YLLs was observed in ≥ 80 years old group. The impact of stroke on Chinese population is more severe compared to the global average levels. Stroke results as the main cause of YLLs in China, while there is no significant difference for the YLDs. Nevertheless, DALYs caused by stroke rank 3th in global epidemiologic study territories, 1st in China.

CHA2DS2-VASc Score and Stroke Prediction in Atrial Fibrillation in Whites, Blacks, and Hispanics

Background and Purpose- Despite modest predictive ability for ischemic stroke (IS), the CHA₂DS₂-VASc score is widely used for stroke prediction in atrial fibrillation. Among patients with atrial fibrillation, we aimed to (1) compare the IS or transient ischemic attack (TIA) incidence by CHA₂DS₂-VASc in blacks and Hispanics versus whites; (2) compare predictive ability of CHA₂DS₂-VASc score for IS or TIA in blacks and Hispanics versus whites; and (3) determine improvement in predictive ability of CHA₂DS₂-VASc score from addition of race/ethnicity. Methods- Using data from Optum Clinformatics, a large administrative claims database, we analyzed patients with atrial fibrillation enrolled in commercial and Medicare Advantage health plans from 2009 to 2015. We computed IS or TIA incidence rates, improvement in C statistic, continuous and categorical net reclassification improvement, and relative integrated discrimination improvement from addition of race/ethnicity to CHA₂DS₂-VASc. Results- A total of 267 419 patients (mean age, 73.1 [SD, 12.3] years; 46.6% women; 84.2% white, 8.5% black, 7.3% Hispanic) were studied. After a mean follow-up of 22 months, there were 6202 IS or TIA events. IS or TIA incidence rates were higher in blacks than Hispanics or whites (1.65, 1.40, and 1.22 cases per 100 person-years, respectively) and increased with higher CHA₂DS₂-VASc, with no race/ethnicity-based differences (P for interaction=0.17). The CHA₂DS₂-VASc and CHA₂DS₂-VASc+race/ethnicity C statistic (95% CI) were 0.679 (0.670-0.686) and 0.679 (0.671-0.688). The CHA₂DS₂-VASc C statistic in the 3 groups were comparable. With addition of race/ethnicity, the categorical net reclassification improvement, continuous net reclassification improvement, and relative integrated discrimination improvement were -0.045 (95% CI, -0.067 to -0.025), 0.045 (95% CI, 0.025-0.068), and 0.016 (95% CI, 0.014-0.018). Conclusions- The predictive ability of CHA₂DS₂-VASc for IS or TIA in atrial fibrillation is comparable among whites, blacks, and Hispanics; hence, it can be used in the latter 2 groups. Addition of race/ethnicity to the CHA₂DS₂-VASc does not improve its predictive ability.

Bioelectrical Impedance Analysis Measures and Clinical Outcomes in CKD

RATIONALE & OBJECTIVE

Bioelectrical impedance analysis (BIA) provides a noninvasive assessment of body composition. BIA measures of cell integrity (phase angle) and hydration (vector length) have been associated with mortality among patients receiving dialysis. Whether these measures are associated with clinical outcomes in patients with chronic kidney disease (CKD) is unknown.

STUDY DESIGN

Observational study.

SETTINGS & PARTICIPANTS

We studied 3,751 participants with CKD in the prospective multicenter Chronic Renal Insufficiency Cohort (CRIC) who had baseline single-frequency BIA performed.

PREDICTORS

Predictors included phase angle and vector length, which were calculated from measurements of resistance and reactance from BIA. We ranked phase angle and vector length into quartiles and compared the 2 narrower quartiles of phase angle and shorter quartiles of vector length with the 2 upper quartiles.

OUTCOMES

Mortality, heart failure, atherosclerotic cardiovascular disease, and progression of CKD (30% decline in estimated glomerular filtration rate or end-stage kidney disease).

ANALYTIC APPROACH

We tested associations of phase angle and vector length with risks for mortality and progression of CKD using Cox proportional hazard models and the association with heart failure and atherosclerotic cardiovascular disease using Fine and Gray models. All models were adjusted for demographics, comorbid conditions, and kidney function.

RESULTS

Mean phase angle and vector length were 6.6°±1.8° and 470 ± 96 Ω/m, respectively. Relative to phase angle ≥ 6.40o, narrower phase angle (<5.59o) was significantly associated with mortality (HR, 1.31; 95% CI, 1.09-1.58). Relative to vector length ≥ 459 Ω/m, shorter vector length (<401 Ω/m) was significantly associated with heart failure (HR, 1.28; 95% CI, 1.01-1.61). Neither measure was associated with atherosclerotic cardiovascular disease or a composite renal end point.

LIMITATIONS

Observational study.

CONCLUSIONS

Adjusted for key confounders, BIA-derived measures of cellular integrity and tissue hydration were significantly associated with death and incident heart failure, respectively.

Midlife vascular risk factors and midlife cognitive status in relation to prevalence of mild cognitive impairment and dementia in later life: The Atherosclerosis Risk in Communities Study

INTRODUCTION

The interplay between midlife vascular risk factors and midlife cognitive function with later life mild cognitive impairment (MCI) and dementia (DEM) is not well understood.

METHODS

In the Atherosclerosis Risk in Communities Study, cardiovascular risk factors and cognition were assessed in midlife, ages 45-64 years. In 2011-2013, 20-25 years later, all consenting Atherosclerosis Risk in Communities participants underwent a cognitive and neurological evaluation and were given adjudicated diagnoses of cognitively normal, MCI, or DEM.

RESULTS

In 5995 participants with complete covariate data, midlife diabetes, hypertension, obesity, and hypercholesterolemia were associated with late-life MCI and DEM. Low midlife cognition function was also associated with greater likelihood of late-life MCI or DEM. Both midlife vascular risk factors and midlife cognitive function remained associated with later life MCI or DEM when both were in the model.

DISCUSSION

Later life MCI and DEM were independently associated with midlife vascular risk factors and midlife cognition.

Cardiovascular Events after New-Onset Atrial Fibrillation in Adults with CKD: Results from the Chronic Renal Insufficiency Cohort (CRIC) Study

BACKGROUND

Atrial fibrillation (AF), the most common sustained arrhythmia in CKD, is associated with poor clinical outcomes in both patients without CKD and patients with dialysis-treated ESRD. However, less is known about AF-associated outcomes in patients with CKD who do not require dialysis.

METHODS

To prospectively examine the association of new-onset AF with subsequent risks of cardiovascular disease events and death among adults with CKD, we studied participants enrolled in the Chronic Renal Insufficiency Cohort Study who did not have AF at baseline. Outcomes included heart failure, myocardial infarction, stroke, and death occurring after diagnosis of AF. We used Cox regression models and marginal structural models to examine the association of incident AF with subsequent risk of cardiovascular disease events and death, adjusting for patient characteristics, laboratory values, and medication use.

RESULTS

Among 3080 participants, 323 (10.5%) developed incident AF during a mean 6.1 years of follow-up. Compared with participants who did not develop AF, those who did had higher adjusted rates of heart failure (hazard ratio [HR], 5.17; 95% confidence interval [95% CI], 3.89 to 6.87), myocardial infarction (HR, 3.64; 95% CI, 2.50 to 5.31), stroke (HR, 2.66; 95% CI, 1.50 to 4.74), and death (HR, 3.30; 95% CI, 2.65 to 4.12). These associations remained robust with additional adjustment for biomarkers of inflammation, cardiac stress, and mineral metabolism; left ventricular mass; ejection fraction; and left atrial diameter.

CONCLUSIONS

Incident AF is independently associated with two- to five-fold increased rates of developing subsequent heart failure, myocardial infarction, stroke, or death in adults with CKD. These findings have important implications for cardiovascular risk reduction.

Racial Differences in Atrial Fibrillation-Related Cardiovascular Disease and Mortality: The Atherosclerosis Risk in Communities (ARIC) Study

IMPORTANCE

The adverse outcomes associated with atrial fibrillation (AF) have been studied in predominantly white cohorts. Racial differences in outcomes associated with AF merit continued investigation.

OBJECTIVE

To evaluate the race-specific associations of AF with stroke, heart failure, coronary heart disease (CHD), and all-cause mortality in a community-based cohort.

DESIGN, SETTING, AND PARTICIPANTS

The Atherosclerosis Risk in Communities (ARIC) Study is a prospective, observational cohort. From 1987 through 1989, the ARIC Study enrolled 15 792 men and women and conducted 4 follow-up examinations (2011-2013) with active surveillance for vital status and hospitalizations. Race was determined by self-report and categorized as white, black, or other.

MAIN OUTCOMES AND MEASURES

Atrial fibrillation (adjudicated using electrocardiograms, hospital discharge codes, and death certificates), stroke, heart failure, CHD, and mortality.

RESULTS

After exclusions, 15 080 participants (mean [SD] age, 54.2 [5.8] years; 8290 women [55.5%]; 3831 black individuals [25.4%]) were included in this analysis. During a mean (SD) follow-up of 20.6 (6.2) years, there were 2348 cases of incident AF. The incident rates of AF per 1000 person-years were 8.1 (95% CI, 7.7-8.5) in white individuals and 5.8 (95% CI, 5.2-6.3) in black individuals. The rates of stroke, heart failure, CHD, and mortality were higher in black individuals with AF than white individuals with AF. The association of AF with these outcomes, estimated with rate differences (rate of the end point in those with AF minus the rate in those without AF per 1000 person-years), also differed by race. The rate difference for stroke in individuals with AF was 10.2 (95% CI, 6.6-13.9) in white individuals and 21.4 (95% CI, 10.2-32.6) in black individuals. For heart failure and CHD, the rate differences were 1.5- to 2.0-fold higher in black individuals than white individuals. White individuals with AF had a rate difference of 55.9 (95% CI, 48.1-63.7) for mortality compared with black individuals, who had a rate difference of 106.0 (95% CI, 86.0-125.9).

CONCLUSIONS AND RELEVANCE

In the prospective ARIC Study, the outcome of AF on the rates of stroke, heart failure, CHD, and mortality was considerably larger in black individuals than white individuals. These results indicate the vulnerability and increased risk in black individuals with AF. Continued investigation of racial differences in AF and its related adverse outcomes are essential to identify and mitigate racial disparities in the treatment of AF.

Association of monocyte myeloperoxidase with incident cardiovascular disease: The Atherosclerosis Risk in Communities Study

Myeloperoxidase (MPO) is a heme-containing peroxidase found in azurophilic granules of neutrophils and monocytes. Epidemiological studies have reported greater plasma MPO concentration to be associated with increased incidence of several cardiovascular diseases (CVD), but the association of intracellular monocyte MPO (mMPO) with CVD is unclear. The prospective population-based Atherosclerosis Risk in Communities (ARIC) cohort study measured mMPO using flow cytometry in 1,465 participants. The association of mMPO with incident cardiovascular disease (CVD, comprising incident coronary heart disease (CHD), heart failure, stroke, peripheral artery disease, and cardiovascular mortality) was examined over a median 9.6 years of follow-up (n = 290 CVD events). There was no statistically significant association between mMPO and all incident CVD events in either age, sex, and race-adjusted proportional hazards models (HR (95% CI) across tertiles of mMPO: 1, 1.09 (0.76, 1.57), and 0.78 (0.52, 1.15), P-trend = 0.21) or adjusted for other major CVD risk factors (HR (95% CI): 1, 1.17 (0.81, 1.69), and 0.87 (0.58, 1.29), P-trend = 0.50). There also was no association between mMPO tertiles and incident CHD, heart failure, or all-cause mortality, examined separately. In conclusion, intracellular monocyte myeloperoxidase was not associated with incident cardiovascular disease in this prospective population-based study.

Racial differences in recurrent ischemic stroke risk and recurrent stroke case fatality

OBJECTIVE

To determine black-white differences in 1-year recurrent stroke and 30-day case fatality after a recurrent stroke in older US adults.

METHODS

We conducted a retrospective cohort study using a 5% random sample of Medicare beneficiaries with fee-for-service health insurance coverage who were hospitalized for ischemic stroke between 1999 and 2013. Hazard ratios for recurrent ischemic stroke and risk ratios for 30-day case fatality comparing blacks to whites were calculated with adjustment for demographics, risk factors, and competing risk of death when appropriate.

RESULTS

Among 128,789 Medicare beneficiaries having an ischemic stroke (mean age 80 years [SD 8 years], 60.4% male), 11.1% were black. The incidence rate of recurrent ischemic stroke per 1,000 person-years for whites and blacks was 108 (95% confidence interval [CI], 106-111) and 154 (95% CI 147-162) , respectively. The multivariable-adjusted hazard ratio for recurrent stroke among blacks compared with whites was 1.36 (95% CI 1.29-1.44). The case fatality after recurrent stroke for blacks and whites was 21% (95% CI 21%-22%) and 16% (95% CI 15%-18%), respectively. The multivariable-adjusted relative risk for mortality within 30 days of a recurrent stroke among blacks compared with whites was 0.82 (95% CI 0.73-0.93).

CONCLUSION

The risk of stroke recurrence among older Americans hospitalized for ischemic stroke is higher for blacks compared to whites, while 30-day case fatality after recurrent stroke remains lower for blacks.

Heart Failure and Cognitive Impairment in the Atherosclerosis Risk in Communities (ARIC) Study

BACKGROUND

Previous studies suggest that heart failure (HF) is an independent risk factor for cognitive decline. A better understanding of the relationship between HF, cognitive status, and cognitive decline in a community-based sample may help clinicians understand disease risk.

OBJECTIVE

To examine whether persons with HF have a higher prevalence of cognitive impairment and whether persons developing HF have more rapid cognitive decline.

DESIGN

This observational cohort study of American adults in the Atherosclerosis Risk in Communities (ARIC) study has two components: cross-sectional analysis examining the association between prevalent HF and cognition using multinomial logistic regression, and change over time analysis detailing the association between incident HF and change in cognition over 15 years.

PARTICIPANTS

Among visit 5 (2011-2013) participants (median age 75 years), 6495 had neurocognitive information available for cross-sectional analysis. Change over time analysis examined the 5414 participants who had cognitive scores and no prevalent HF at visit 4 (1996-1998).

MEASUREMENTS

The primary outcome was cognitive status, classified as normal, mild cognitive impairment [MCI], and dementia on the basis of standardized cognitive tests (delayed word recall, word fluency, and digit symbol substitution). Cognitive change was examined over a 15-year period. Control variables included socio-demographic, vascular, and smoking/drinking measures.

RESULTS

At visit 5, participants with HF had a higher prevalence of dementia (adjusted relative risk ratio [RRR] = 1.60 [95% CI 1.13, 2.25]) and MCI (RRR = 1.36 [1.12, 1.64]) than those without HF. A decline in cognition between visits 4 and 5 was - 0.07 standard deviation units [- 0.13, - 0.01] greater among persons who developed HF compared to those who did not. Results did not differ by ejection fraction.

CONCLUSION

HF is associated with neurocognitive dysfunction and decline independent of other co-morbid conditions. Further study is needed to determine the underlying pathophysiology.

Association of left ventricular hypertrophy with cognitive decline and dementia risk over 20 years: The Atherosclerosis Risk In Communities-Neurocognitive Study (ARIC-NCS)

BACKGROUND

Left ventricular hypertrophy (LVH) is an indicator of organ damage largely due to hypertension. We assessed whether LVH was associated with dementia and cognitive function in the Atherosclerosis Risk in Communities study.

METHODS

Our analysis included 12,665 individuals (23% black race, 56% female, mean age 57) who attended visit 2 in 1990-1992. Cornell voltage (SV3 + RaVL) was derived from 12-lead electrocardiograms and dichotomized as LVH using sex-specific criteria (>28 mm men; >22 mm women). Incident dementia was defined by expert review using a predetermined algorithm, and cognitive function was measured longitudinally using 3 tests. A Cox model was used to evaluate the association between time-dependent LVH and dementia adjusted for time-varying covariates from 1990 to 2013. Linear regression models fit with generalized estimating equations were used to evaluate LVH with cognitive function.

RESULTS

During a mean follow-up of 18 years, we identified 544 participants with LVH and 1,195 dementia cases. LVH was associated with a higher risk of dementia: multivariable hazard ratio = 1.90; 95% CI: 1.47-2.44. Those with LVH had lower cognitive scores at baseline; however, there was no difference in the rate of cognitive decline over 20 years in those with LVH versus those without LVH.

CONCLUSIONS

In this population-based study, LVH measured during midlife was associated with an increased risk of incident dementia; however, LVH was not associated with additional cognitive decline. These results underscore the need for hypertension control to prevent subclinical brain injury.

The Ottawa SAH search algorithms: protocol for a multi- centre validation study of primary subarachnoid hemorrhage prediction models using health administrative data (the SAHepi prediction study protocol)

Background

Conducting prospective epidemiological studies of hospitalized patients with rare diseases like primary subarachnoid hemorrhage (pSAH) are difficult due to time and budgetary constraints. Routinely collected administrative data could remove these barriers. We derived and validated 3 algorithms to identify hospitalized patients with a high probability of pSAH using administrative data. We aim to externally validate their performance in four hospitals across Canada.

Methods

Eligible patients include those ≥18 years of age admitted to these centres from January 1, 2012 to December 31, 2013. We will include patients whose discharge abstracts contain predictive variables identified in the models (ICD-10-CA diagnostic codes I60** (subarachnoid hemorrhage), I61** (intracranial hemorrhage), 162** (other nontrauma intracranial hemorrhage), I67** (other cerebrovascular disease), S06** (intracranial injury), G97 (other postprocedural nervous system disorder) and CCI procedural codes 1JW51 (occlusion of intracranial vessels), 1JE51 (carotid artery inclusion), 3JW10 (intracranial vessel imaging), 3FY20 (CT scan (soft tissue of neck)), and 3OT20 (CT scan (abdominal cavity)). The algorithms will be applied to each patient and the diagnosis confirmed via chart review. We will assess each model’s sensitivity, specificity, negative and positive predictive value across the sites.

Discussion

Validating the Ottawa SAH Prediction Algorithms will provide a way to accurately identify large SAH cohorts, thereby furthering research and altering care.

Declining Lung Function and Cardiovascular Risk: The ARIC Study

BACKGROUND

Pulmonary dysfunction predicts incident cardiovascular disease (CVD).

OBJECTIVES

The purpose of this study was to evaluate whether longitudinal decline in lung function is associated with incident heart failure (HF), coronary heart disease (CHD), and stroke.

METHODS

Among 10,351 participants in the ARIC (Atherosclerosis Risk In Communities) study free of CVD, rapid lung function decline was defined as the greatest quartile (n = 2,585) of decline in either forced expiratory volume in 1 s (FEV1) (>1.9% decline/year) or forced vital capacity (FVC) (>2.1% decline/year) over 2.9 ± 0.2 years. The relationship between rapid decline in FEV1 or FVC and subsequent incident HF, CHD, stroke, or a composite of these was assessed using multivariable Cox regression adjusting for the baseline spirometry value, demographics, height, body mass index, heart rate, diabetes, hypertension, low-density lipoprotein, use of lipid-lowering medication, N-terminal fragment of prohormone for B-type natriuretic peptide, and smoking.

RESULTS

The mean age was 54 ± 6 years, 56% were women, and 81% were white. At 17 ± 6 years of follow-up, HF occurred in 14%, CHD 11%, stroke 6%, and the composite in 24%. Rapid decline in FEV1 and in FVC were both associated with a heightened risk of incident HF (hazard ratio [HR]: 1.17; 95% confidence interval [CI]: 1.04 to 1.33; p = 0.010; and HR: 1.27; 95% CI: 1.12 to 1.44; p < 0.001; respectively), with rapid decline in FEV1 most prognostic in the first year of follow-up (HR: 4.22; 95% CI: 1.34 to 13.26; p = 0.01). Rapid decline in FEV1 was also associated with incident stroke (HR: 1.25; 95% CI: 1.04 to 1.50; p = 0.015).

CONCLUSIONS

A rapid decline in lung function, assessed by serial spirometry, is associated with a higher incidence of subsequent CVD, particularly incident HF.

Prognostic Implications of Single-Sample Confirmatory Testing for Undiagnosed Diabetes: A Prospective Cohort Study

Background

Current clinical definitions of diabetes require repeated blood work to confirm elevated levels of glucose or hemoglobin A1c (HbA1c) to reduce the possibility of a false-positive diagnosis. Whether 2 different tests from a single blood sample provide adequate confirmation is uncertain.

Objective

To examine the prognostic performance of a single-sample confirmatory definition of undiagnosed diabetes.

Design

Prospective cohort study.

Setting

The ARIC (Atherosclerosis Risk in Communities) study.

Participants

13 346 ARIC participants (12 268 without diagnosed diabetes) with 25 years of follow-up for incident diabetes, cardiovascular outcomes, kidney disease, and mortality.

Measurements

Confirmed undiagnosed diabetes was defined as elevated levels of fasting glucose (≥7.0 mmol/L [≥126 mg/dL]) and HbA1c (≥6.5%) from a single blood sample.

Results

Among 12 268 participants without diagnosed diabetes, 978 had elevated levels of fasting glucose or HbA1c at baseline (1990 to 1992). Among these, 39% had both (confirmed undiagnosed diabetes), whereas 61% had only 1 elevated measure (unconfirmed undiagnosed diabetes). The confirmatory definition had moderate sensitivity (54.9%) but high specificity (98.1%) for identification of diabetes cases diagnosed during the first 5 years of follow-up, with specificity increasing to 99.6% by 15 years. The 15-year positive predictive value was 88.7% compared with 71.1% for unconfirmed cases. Confirmed undiagnosed diabetes was significantly associated with cardiovascular and kidney disease and mortality, with stronger associations than unconfirmed diabetes.

Limitation

Lack of repeated measurements of fasting glucose and HbA1c.

Conclusion

A single-sample confirmatory definition of diabetes had a high positive predictive value for subsequent diagnosis and was strongly associated with clinical end points. Our results support the clinical utility of using a combination of elevated fasting glucose and HbA1c levels from a single blood sample to identify undiagnosed diabetes in the population.

Primary Funding Source

National Institute of Diabetes and Digestive and Kidney Diseases and National Heart, Lung, and Blood Institute.

Association of orthostatic hypotension with incident dementia, stroke, and cognitive decline

OBJECTIVE

To examine associations of orthostatic hypotension (OH) with dementia and long-term cognitive decline and to update previously published results in the same cohort for stroke with an additional 16 years of follow-up.

METHODS

We analyzed data from 11,709 participants without a history of coronary heart disease or stroke who attended the baseline examination (1987-1989) of the prospective Atherosclerosis Risk in Communities (ARIC) study. OH was defined as a drop in systolic blood pressure (BP) of at least 20 mm Hg or a drop in diastolic BP of at least 10 mm Hg on standing. Dementia was ascertained via examination, contact with participants or their proxy, or medical record surveillance. Ischemic stroke was ascertained via cohort surveillance of hospitalizations, cohort follow-up, and linkage with registries. Both outcomes were adjudicated. Cognitive function was ascertained via 3 neuropsychological tests administered in 1990 to 1992 and 1996 to 1998 and a full battery of tests in 2011 to 2013. Scores were summarized and reported as SDs. We used adjusted Cox regression and linear mixed models.

RESULTS

Over ≈25 years, 1,068 participants developed dementia and 842 had an ischemic stroke. Compared to persons without OH at baseline, those with OH had a higher risk of dementia (hazard ratio [HR] 1.54, 95% confidence interval [CI] 1.20-1.97) and ischemic stroke (HR 2.08, 95% CI 1.65-2.62). Persons with OH had greater, although nonsignificant, cognitive decline over 20 years (SD 0.09, 95% CI -0.02 to 0.21).

CONCLUSIONS

OH assessed in midlife was independently associated with incident dementia and ischemic stroke. Additional studies are needed to elucidate potential mechanisms for these associations and possible applications for prevention.

Cardiovascular fat in women at midlife: effects of race, overall adiposity, and central adiposity. The SWAN Cardiovascular Fat Study

OBJECTIVES

Cardiovascular fat (CF) is associated with greater coronary heart disease (CHD) risk. Postmenopausal women have greater CF volumes than premenopausal women, and the association between specific CF depot volumes and CHD risk is more pronounced after menopause. Race, central adiposity, and visceral adiposity are important factors that could impact CF volumes. Whether racial differences in CF volumes and in their associations with central (visceral fat [VAT]) and general adiposity (body mass index [BMI]) exist in midlife women have not been addressed before.

METHODS

In all, 524 participants from the Study of Women's Health Across the Nation (mean age: 50.9 ± 2.9 years; 62% White and 38% Black) who had data on CF volumes (epicardial fat [EAT], paracardial fat [PAT], total heart fat, and aortic perivascular fat), VAT, and BMI were studied.

RESULTS

In models adjusted for age, study site, menopausal status, comorbid conditions, alcohol consumption, and physical activity, Black women had 19.8% less EAT, 24.5% less PAT, 20.4% less total heart fat, and 13.2% less perivascular fat than White women (all P < 0.001). These racial differences remained significant after additional adjustment for BMI or VAT. Race significantly modified associations between adiposity measures and CF volumes. Every 1-SD higher BMI was associated with 66.7% greater PAT volume in White compared with 42.4% greater PAT volume in Black women (P = 0.004), whereas every 1-SD higher VAT was associated with 32.3% greater EAT volume in Black compared with 25.3% greater EAT volume in White women (P = 0.039).

CONCLUSIONS

Racial differences were found in CF volumes and in their associations with adiposity measures among midlife women. Future research should determine how race-specific changes in CF volumes impact CHD risk in women.

Carotid Intima-Media Thickness and Silent Brain Infarctions in a Biracial Cohort: The Atherosclerosis Risk in Communities (ARIC) Study

BACKGROUND

Both hypertensive and atherosclerotic processes contribute to common carotid artery intima-media thickness (CCA-IMT). Elevated CCA-IMT may be indicative of subclinical cerebrovascular disease; however, its role in the absence of concomitant carotid artery plaque is uncertain, and few studies have examined associations in Black populations.

MATERIALS AND METHODS

At cohort visit 3 (1993-1995) a subset of stroke-free participants (641 Blacks and 702 Whites, mean age 63) from the Atherosclerosis Risk in Communities (ARIC) study was imaged by brain MRI and carotid ultrasound. A CCA-IMT >0.9 mm was considered elevated. Asymptomatic brain lesions ≥3 mm were considered silent brain infarctions (SBI). Subcortical SBI measuring 3 to <20 mm were considered lacunes. Associations between elevated CCA-IMT and SBI were analyzed with Poisson regression.

RESULTS

Elevated CCA-IMT was identified in 168 participants (16% of Blacks, 10% of Whites), and SBI were observed in 156 (15% of Blacks, 8% of Whites). Elevated CCA-IMT was strongly related to anterior circulation SBI, posterior circulation SBI, and lacunes. After adjustments, elevated CCA-IMT remained associated with greater number of lacunes in Blacks ([prevalence ratio, PR] = 1.60; 95% confidence interval [CI]: 1.02-2.51), but not Whites (PR = 0.85; 95% CI: 0.35-2.04); P value for interaction = 0.12. Among Black participants without concomitant carotid plaque, elevated CCA-IMT was associated with twice the number of lacunes (PR = 2.00; 95% CI: 1.05-3.82).

CONCLUSIONS

In older Black adults, elevated CCA-IMT is independently associated with lipohyalinosis of the cerebral small vessels, irrespective of concomitant carotid plaque and vascular risk factors.

Remnant-Like Particle Cholesterol, Low-Density Lipoprotein Triglycerides, and Incident Cardiovascular Disease

BACKGROUND

Hypertriglyceridemia is associated with increased remnant-like particle cholesterol (RLP-C) and triglycerides in low-density lipoprotein (LDL-TG). Recent studies have focused on atherogenicity of RLP-C, with few data on LDL-TG.

OBJECTIVES

The aim of this study was to examine associations of RLP-C and LDL-TG with incident cardiovascular disease (CVD) events and genetic variants in the ARIC (Atherosclerosis Risk In Communities) study.

METHODS

Fasting plasma RLP-C and LDL-TG levels were measured in 9,334 men and women without prevalent CVD. Participants were followed for incident CVD events (coronary heart disease and ischemic stroke) for up to 16 years. Associations between LDL-TG and RLP-C levels and genetic variants were assessed by whole-exome sequencing using single-variant analysis for common variants and gene-based burden tests for rare variants; both an unbiased and a candidate gene approach were explored.

RESULTS

RLP-C and LDL-TG levels were correlated with triglyceride levels (r = 0.85 and r = 0.64, p < 0.0001). In minimally adjusted analyses, RLP-C and LDL-TG were associated with CVD risk, but in models adjusted for traditional risk factors including lipids, only LDL-TG was associated with incident CHD (hazard ratio: 1.28; 95% confidence interval: 1.10 to 1.50) and stroke (hazard ratio: 1.47; 95% confidence interval: 1.13 to 1.92). A common APOE variant, rs7412, had the strongest association with LDL-TG and RLP-C (p < 5 × 10-8).

CONCLUSIONS

RLP-C and LDL-TG levels were predictive of CVD and associated with APOE variants. LDL-TG may represent a marker of dysfunctional remnant lipoprotein metabolism associated with increased CVD risk. Further research is needed to determine whether LDL-TG plays a causal role in CVD and may be a target for therapy.

Independent Association of Plasma Hydroxysphingomyelins With Physical Function in the Atherosclerosis Risk in Communities (ARIC) Study

Background

Plasma metabolites such as phosphatidylcholines and sphingomyelins (SMs) are associated with an age-related cognitive decline. However, their relations to age-related physical function decline remain largely unknown.

Methods

We examined the cross-sectional relations of 12 plasma metabolites (including four phosphatidylcholines and four SMs) with physical function in 383 older adults in the At herosclerosis Risk in Communities Study at the fifth exam (2011-2013, mean age [standard deviation (SD)]: 78.0 [5.5], 54.4% women, 28.3% African Americans). Physical function was assessed using grip strength, Short Physical Performance Battery, and 4-m walking speed. Individual metabolites were log-transformed and standardized. Multivariable linear regression was performed to account for demographics, APOE genotype, cardiovascular risk factors, comorbidities, use of antihypertensive and lipid-lowering medications, depressive symptoms, and cognition.

Results

Lower concentrations of asymmetric dimethylarginine and higher concentrations of SM (OH) C22:1, SM (OH) C22:2, and SM (OH) C24:1 were associated with physical function measures. In particular, SM (OH) C22:1 and SM (OH) C24:1 were associated with all three measures of physical function: β-coefficients (95% confidence interval) with grip strength were 0.89 kg (0.00, 1.78) and 0.86 kg (0.10, 1.61) per 1 SD higher concentration, respectively; with Short Physical Performance Battery score, were 0.61 (0.34, 0.88) and 0.41 (0.19, 0.63) per 1 SD difference, respectively; with 4-m walking speed were 0.035 m/s (0.013, 0.056) and 0.035 m/s (0.028, 0.047), respectively.

Conclusions

Plasma SM (OH)s may be independently associated with physical function in older adults.

GDF-15, Galectin 3, Soluble ST2, and Risk of Mortality and Cardiovascular Events in CKD

RATIONALE & OBJECTIVE

Inflammation, cardiac remodeling, and fibrosis may explain in part the excess risk for cardiovascular disease (CVD) in patients with chronic kidney disease (CKD). Growth differentiation factor 15 (GDF-15), galectin 3 (Gal-3), and soluble ST2 (sST2) are possible biomarkers of these pathways in patients with CKD.

STUDY DESIGN

Observational cohort study.

SETTING & PARTICIPANTS

Individuals with CKD enrolled in either of 2 multicenter CKD cohort studies: the Seattle Kidney Study or C-PROBE (Clinical Phenotyping and Resource Biobank Study).

EXPOSURES

Circulating GDF-15, Gal-3, and sST2 measured at baseline.

OUTCOMES

Primary outcome was all-cause mortality. Secondary outcomes included hospitalization for physician-adjudicated heart failure and the atherosclerotic CVD events of myocardial infarction and cerebrovascular accident.

ANALYTIC APPROACH

Cox proportional hazards models used to test the association of each biomarker with each outcome, adjusting for demographics, CVD risk factors, and kidney function.

RESULTS

Among 883 participants, mean estimated glomerular filtration rate was 49±19mL/min/1.73m². Higher GDF-15 (adjusted HR [aHR] per 1-SD higher, 1.87; 95% CI, 1.53-2.29), Gal-3 (aHR per 1-SD higher, 1.51; 95% CI, 1.36-1.78), and sST2 (aHR per 1-SD higher, 1.36; 95% CI, 1.17-1.58) concentrations were significantly associated with mortality. Only GDF-15 level was also associated with heart failure events (HR per 1-SD higher, 1.56; 95% CI, 1.12-2.16). There were no detectable associations between GDF-15, Gal-3, or sST2 concentrations and atherosclerotic CVD events.

LIMITATIONS

Event rates for heart failure and atherosclerotic CVD were low.

CONCLUSIONS

Adults with CKD and higher circulating GDF-15, Gal-3, and sST2 concentrations experienced greater mortality. Elevated GDF-15 concentration was also associated with an increased rate of heart failure. Further work is needed to elucidate the mechanisms linking these circulating biomarkers with CVD in patients with CKD.

Blood biomarkers in ischemic stroke: Role of biomarkers in differentiation of clinical phenotype

Stroke is the major cause of death and disability worldwide and ischemic stroke contributes 80% among them. Although limited number of patients display hemorrhagic stroke (HS), the disability and death rate are higher in HS. Several studies have been reported on identification of suitable markers for diagnosis of stroke, but none of them holds true worldwide. These observations direct toward identification of population-specific biomarker of stroke. In this study, we screened various blood biomarkers in a large cohort of well-characterized Chinese stroke patients and healthy controls. A total of 308 stroke patients including 262 acute ischemic stroke (AIS) patients and 42 HS patients were enrolled in the study and blood samples were collected within 6–24 h of stroke onset. In addition, 46 stroke mimic subjects were included for comparison of blood markers with stroke patients. Furthermore, healthy controls (n = 200) and patient controls (n = 125) from similar ethnic group were enrolled in the study. Biomarkers (S100 calcium-binding protein B (S100B), C-reactive protein (CRP), interleukin 6 (IL-6), plasminogen activator inhibitor-1 (PAI-1), matrix metallopeptidase 9 (MMP-9), P-selectin, intercellular adhesion molecule 1 (ICAM-1), tumor necrosis factor α (TNF-α), low-density lipoprotein (LDL) cholesterol, interleukin 10 (IL-10), nitric oxide (NO), and glial fibrillary acidic protein (GFAP)) were quantified by ELISA. Blood levels of S100B, CRP, IL-6, PAI-1, MMP-9, P-selectin, ICAM-1, and TNF-α were significantly higher in AIS and HS patients compared to healthy controls, patient controls, and stroke mimic patients. Receiver operating characteristic (ROC) curve analysis revealed CRP, IL-6, PAI-1, P-selectin, and TNF-α as possible biomarkers for AIS patients, and HS patients can be diagnosed based on S100B, IL-6, PAI-1, MMP-9, and TNF-α. Interestingly, significant area under ROC curves were observed for plasma S100B and CRP for differentiating AIS from HS. The results of this study validated certain blood parameters used for diagnosis of AIS or HS in Chinese patients. Furthermore, S100B and CRP are promising biomarkers for differentiation of AIS from HS.

Short-Term Global Cardiovascular Disease Risk Prediction in Older Adults

BACKGROUND

Current prevention guidelines recommend using the Pooled Cohort Equation (PCE) for 10-year atherosclerotic cardiovascular disease (CVD) risk assessment. However, the PCE has serious limitations in older adults: it excludes heart failure (HF) hospitalization, estimates 10-year risk, which may not be the most relevant time frame, and is not indicated for individuals age >79 years.

OBJECTIVES

This study sought to determine whether adding biomarkers to PCE variables improves global CVD (coronary heart disease, stroke, and HF) risk prediction in older adults over a shorter time period.

METHODS

Atherosclerosis Risk in Communities study participants without prevalent CVD including HF (n = 4,760; age 75.4 ± 5.1 years) were followed for incident global CVD events. Adding N-terminal pro-B-type natriuretic peptide, high-sensitivity cardiac troponin T, and high-sensitivity C-reactive protein to the PCE and a "lab model" with the biomarkers, age, race, and gender were assessed for prediction improvement. Area under the receiver operating characteristic curve (AUC) and net reclassification index (NRI) were calculated.

RESULTS

Over median follow-up of ∼4 years, incident HF was the leading CVD event (n = 193 vs. 118 coronary heart disease and 81 stroke events). Compared to the PCE, each biomarker improved risk prediction. The largest improvement in risk prediction metrics was with the addition of all 3 biomarkers (ΔAUC 0.103; continuous NRI 0.484). The lab model also performed better than the PCE model (ΔAUC 0.091, continuous NRI 0.355).

CONCLUSIONS

Adding biomarkers to the PCE or a simpler "lab model" improves short-term global CVD risk prediction and may be useful to inform short-term preventive strategies in older adults.

Usefulness of Lipoprotein-Associated Phospholipase A2 Activity and C-Reactive Protein in Identifying High-Risk Smokers for Atherosclerotic Cardiovascular Disease (from the Atherosclerosis Risk in Communities Study)

Despite the causal role of cigarette smoking in atherosclerotic cardiovascular disease (ASCVD), the underlying mechanisms are not fully understood. We evaluated the joint relation between smoking and inflammatory markers with ASCVD risk. We tested cross-sectional associations of self-reported smoking status (never, former, current) and intensity (packs/day) with lipoprotein-associated phospholipase A2 (Lp-PLA2) activity and high-sensitivity C-reactive protein (hsCRP) in 10,506 Atherosclerosis Risk in Communities participants at Visit 4 (1996 to 1998). Using Cox hazard models adjusted for demographic and traditional ASCVD risk factors, we examined the associations of smoking status and intensity with incident adjudicated ASCVD events (n = 1,745 cases) over an average of 17 years, stratified by Lp-PLA2 and hsCRP categories. Greater packs/day smoked was linearly associated with higher levels of both Lp-PLA2 and hsCRP among current smokers. Compared with never smokers, the hazard ratio for incident ASCVD in current smokers was 2.04 (95% CI 1.76 to 2.35). Among current smokers, the risk for ASCVD per 1 pack/day greater was 1.39 (1.10 to 1.76). Both Lp-PLA2 activity ≥253 nmol/min/ml and hsCRP >3 mg/L identified current smokers at the highest risk for incident ASCVD, with similar hazard ratios. hsCRP risk-stratified current smokers better based on intensity. Among current smokers, hsCRP improved ASCVD prediction beyond traditional risk factors better than Lp-PLA2 (C-statistic 0.675 for hsCRP vs 0.668 for Lp-PLA2, p = 0.001). In this large cohort with long follow-up, we found a dose-response relation between smoking intensity with Lp-PLA2 activity, hsCRP, and ASCVD events. Although both Lp-PLA2 activity and hsCRP categories identified high risk among current smokers, hsCRP may better stratify risk of future ASCVD.

Alcohol Consumption and Incident Stroke Among Older Adults

Objectives

This study examines the relationship between alcohol consumption and incident stroke among older adults and tests whether alcohol consumption contributes to observed race and sex differences in stroke.

Method

Data are from a U.S. national cohort of black and white adults aged 45 and older, the REasons for Geographic And Racial Differences in Stroke (REGARDS) study. Current and past drinking levels were reported at baseline (2003-2007). Participants who had never had a stroke were followed for adjudicated stroke events through September 2015 (n = 27,265). We calculated Cox proportional hazard models for stroke, adjusting for demographic, socioeconomic, behavioral, and health characteristics.

Results

Participants, mean age 64.7 years, consumed on average 2.2 drinks/week and experienced 1,140 first-time stroke events over median 9.1 years follow-up. Nondrinkers had a 12% higher risk of stroke than current drinkers; the risk of stroke among nondrinkers largely reflected high risks among past drinkers; these differences were explained by socioeconomic characteristics. Among current drinkers, light drinkers had significantly lower stroke risks than moderate drinkers after accounting for demographic, socioeconomic, behavioral, and health characteristics. Implications of alcohol did not differ between blacks and whites but did differ by sex: Especially among women, nondrinkers, and specifically past drinkers, had higher risks; these differences were largely explained by health characteristics and behaviors. Alcohol did not explain race and sex differences in stroke incidence.

Discussion

Among older adults, those who used to, but no longer, drink had higher risks of stroke, especially among women; current light drinkers had the lowest risk of stroke.

Sex Differences in the Association of Diabetes With Cardiovascular Disease Outcomes Among African-American and White Participants in the Atherosclerosis Risk in Communities Study

A sex × diabetes interaction in cardiovascular disease (CVD) has been established among white persons; however, it is unknown whether this interaction occurs among African Americans. We hypothesized that there was a multiplicative sex × diabetes interaction for CVD among African Americans participating in the Atherosclerosis Risk in Communities Study (1987-2013). Race-specific Cox models were run in three stages: Stage 1 examined baseline diabetes status; stage 2 examined baseline diabetes status with the competing risk of non-CVD death; and stage 3 examined time-varying diabetes status with a competing risk of non-CVD death. There were 1,073 incident CVD events among 3,767 African Americans and 2,475 among 10,291 white persons. Among African Americans, in stage 1 analysis, the hazard ratio for women with diabetes was 2.3 (95% confidence interval (CI): 2.0, 2.7) compared with women without diabetes after adjustment for age, and the corresponding hazard ratio for men was 1.8 (95% CI: 1.5, 2.1) (P for interaction = 0.014). After full adjustment, the diabetes hazard ratio was attenuated to 2.0 (95% CI: 1.8, 2.3) among women and remained 1.8 (95% CI: 1.5, 2.1) for men (P for interaction = 0.058). A synergistic influence on CVD risk between being a black woman and having diabetes was consistent across stage 2 and stage 3 analyses, with marginally significant interaction, mirroring sex differences seen in whites.

Joint effects of OSA and self-reported sleepiness on incident CHD and stroke

BACKGROUND

Although excessive daytime sleepiness (EDS) is a common symptom of obstructive sleep apnea (OSA), and both EDS and OSA have separately been associated with increased risk of cardiovascular disease (CVD), their joint association with CVD risk is unknown.

METHODS

Among 3874 Sleep Heart Health Study (SHHS) participants without prevalent CVD, moderate to severe OSA was defined by an apnea hypopnea index (AHI) ≥ 15 on an in-home polysomnography. EDS was defined as an Epworth Sleepiness Scale score ≥11. Incident CVD events included total CVD events (coronary heart disease (CHD) and stroke), as well as CHD and stroke separately. Cox proportional hazards models adjusted for age, sex, alcohol, smoking, and body mass index.

RESULTS

Compared to those with AHI <15, the hazard ratios (95% CI) for the association of moderate-severe OSA (AHI ≥15) were as follows: CVD 1.06 (0.85-1.33); CHD 1.08 (0.85-1.33); and stroke 1.18 (0.75-1.84). Weak associations between EDS and CVD risk = [1.22 (1.01-1.47)] and CHD risk [1.25 (1.02-1.53)] were present, however there were none for stroke risk [1.10 (0.75-1.63)]. When jointly modeled, both AHI ≥15 and EDS (compared with having AHI <15 and no EDS) was associated with HRs of 1.26 (0.91-1.73) for CVD, 1.24 (0.87-1.75) for CHD and 1.49 (0.78-2.86) for stroke. There were no statistically significant interactions between daytime sleepiness and OSA on the multiplicative or additive scales.

CONCLUSIONS

Having both EDS and moderate-severe OSA was not associated with an increased risk of CVD in the SHHS data.

Periodontal Disease, Regular Dental Care Use, and Incident Ischemic Stroke

BACKGROUND AND PURPOSE

Periodontal disease is independently associated with cardiovascular disease. Identification of periodontal disease as a risk factor for incident ischemic stroke raises the possibility that regular dental care utilization may reduce the stroke risk.

METHODS

In the ARIC (Atherosclerosis Risk in Communities) study, pattern of dental visits were classified as regular or episodic dental care users. In the ancillary dental ARIC study, selected subjects from ARIC underwent fullmouth periodontal measurements collected at 6 sites per tooth and classified into 7 periodontal profile classes (PPCs).

RESULTS

In the ARIC study 10 362 stroke-free participants, 584 participants had incident ischemic strokes over a 15-year period. In the dental ARIC study, 6736 dentate subjects were assessed for periodontal disease status using PPC with a total of 299 incident ischemic strokes over the 15-year period. The 7 levels of PPC showed a trend toward an increased stroke risk (χ² trend P<0.0001); the incidence rate for ischemic stroke/1000-person years was 1.29 for PPC-A (health), 2.82 for PPC-B, 4.80 for PPC-C, 3.81 for PPC-D, 3.50 for PPC-E, 4.78 for PPC-F, and 5.03 for PPC-G (severe periodontal disease). Periodontal disease was significantly associated with cardioembolic (hazard ratio, 2.6; 95% confidence interval, 1.2-5.6) and thrombotic (hazard ratio, 2.2; 95% confidence interval, 1.3-3.8) stroke subtypes. Regular dental care utilization was associated with lower adjusted stroke risk (hazard ratio, 0.77; 95% confidence interval, 0.63-0.94).

CONCLUSIONS

We confirm an independent association between periodontal disease and incident stroke risk, particularly cardioembolic and thrombotic stroke subtype. Further, we report that regular dental care utilization may lower this risk for stroke.

The Frequency and Risk Factors for Ischemic Stroke in Myotonic Dystrophy Type 1 Patients

INTRODUCTION

Patients with myotonic dystrophy type 1 have several cardiac abnormalities, especially myocardial conduction disorders. Few studies have investigated cerebral infarction. We investigated the frequency of both symptomatic and asymptomatic ischemic strokes in patients with myotonic dystrophy type 1.

METHODS

Patients who were diagnosed with myotonic dystrophy type 1 using genetic testing or clinical examinations at Asahikawa Medical Center were included. We retrospectively reviewed their medical history, neuroradiological imaging, electrocardiograms, and treatment. Their CHADS2 and CHA2DS2-VASc scores were calculated.

RESULT

A total of 108 patients were diagnosed with myotonic dystrophy type 1. Magnetic resonance imaging was performed in 72 and 1 patient whose results were not available was excluded. Among these, 2 patients had atrial flutter and 3 had atrial fibrillation. Regarding the CHADS2 score, 11 patients scored more than 2. Regarding the CHA2DS2-VASc score, 22 patients scored more than 2. Ischemic strokes were found in 9 patients with 1 having an atrial flutter and 4 having atrial fibrillation. All patients with stroke had CHADS2 and CHA2DS2-VASc scores higher than 2. There were significant differences between the 2 groups in atrial fibrillation (P < .001), CHADS2 score (P < .001), and CHA2DS2-VASc score (P < .001).

CONCLUSIONS

Ischemic stroke in patients with myotonic dystrophy type 1 is associated with atrial fibrillation. The CHADS2 score seems to be useful for the management of patients with myotonic dystrophy type 1. Repeated electrocardiograms are necessary for managing these patients.

Chart validation of inpatient ICD-9-CM administrative diagnosis codes for ischemic stroke among IGIV users in the Sentinel Distributed Database

The Sentinel Distributed Database (SDD) is a large database of patient-level medical and prescription records, primarily derived from insurance claims and electronic health records, and is sponsored by the U.S. Food and Drug Administration for drug safety assessments. In this chart validation study, we report on the positive predictive value (PPV) of inpatient ICD-9-CM acute ischemic stroke (AIS) administrative diagnosis codes (433.x1, 434.xx, and 436) in the SDD.As part of an assessment of the risk of thromboembolic adverse events following treatment with intravenous immune globulin (IGIV), charts were obtained for 131 potential post-IGIV AIS cases. Charts were abstracted by trained nurses and then adjudicated by stroke experts using pre-specified diagnostic criteria.Case status could be determined for 128 potential AIS cases, of which 34 were confirmed. The PPVs for the inpatient AIS diagnoses recorded in the SDD were 27% overall [95% confidence interval (95% CI): 19-35], 60% (95% CI: 32-84) for principal-position diagnoses, 42% (95% CI: 28-57) for secondary diagnoses, and 6% (95% CI: 2-15) for position-unspecified diagnoses (which in the SDD generally originate from separate physician claims associated with an inpatient stay).Position-unspecified diagnoses were unlikely to represent true AIS cases. PPVs for principal and secondary inpatient diagnosis codes were higher, but still meaningfully lower than estimates from prior chart validation studies. The low PPVs may be specific to the IGIV user study population. Additional research is needed to assess the validity of AIS administrative diagnosis codes in other study populations within the SDD.

Design and implementation of observational studies to measure disease burden with a focus on stroke

Observational epidemiological studies have the dual goals of measuring disease burden and assessing the association between exposures and outcomes. This report focuses on the first of these goals and provides an overview of design considerations of commonly used approaches, specifically community surveillance studies, cross-sectional studies, and longitudinal cohort studies. Each of these designs has strengths and weaknesses, with no study design being superior in all cases. Rather, these designs are complementary to achieve a better understanding of the burden of stroke.

Lipoprotein-associated phospholipase A2 and risk of incident peripheral arterial disease: Findings from The Atherosclerosis Risk in Communities study (ARIC)

BACKGROUND AND AIMS

Results from prospective studies evaluating the relationship between elevated lipoprotein-associated phospholipase A₂ (Lp-PLA₂) activity and incident peripheral arterial disease (PAD) have been mixed. We investigated whether higher Lp-PLA₂ levels are associated with increased risk of incident PAD and whether PLA2G7 gene variants, which result in lower Lp-PLA₂ levels, are associated with reduced risk of incident PAD.

METHODS

Our analysis included 9922 participants (56% female; 21% African-American; mean age 63 years) without baseline PAD at ARIC Visit 4 (1996-1998), who had Lp-PLA₂ activity measured and were subsequently followed for the development of PAD, defined by occurrence of a PAD-related hospitalization, through 2012. Cox proportional hazard models were performed to determine the association of Lp-PLA₂ levels and PLA2G7 gene variants with incident PAD.

RESULTS

During a median follow-up of 14.9 years, we identified 756 incident cases of PAD. In analyses adjusting for age, race, and sex, each standard deviation increment in Lp-PLA₂ activity (62 nmol/ml/min) was associated with a higher risk of developing PAD (hazard ratio (HR) 1.17; 95% confidence interval (CI) 1.09, 1.26). This association remained significant after additional adjustment for risk factors, other cardiovascular disease, and medication use, but was strongly attenuated (HR: 1.09; 95% CI 1.00, 1.20). PLA2G7 variants were not associated with a lower risk of PAD in both white carriers (HR: 1.21; 95% CI: 0.17-8.56) and African-American carriers (HR: 0.83; 95% CI: 0.41-1.67), although statistical power was quite limited for this analysis, particularly in whites.

CONCLUSIONS

While higher Lp-PLA₂ activity was associated with an increased risk for incident PAD, it is likely a risk marker largely represented by traditional risk factors.

Cardiovascular Health in African Americans: A Scientific Statement From the American Heart Association

BACKGROUND AND PURPOSE

Population-wide reductions in cardiovascular disease incidence and mortality have not been shared equally by African Americans. The burden of cardiovascular disease in the African American community remains high and is a primary cause of disparities in life expectancy between African Americans and whites. The objectives of the present scientific statement are to describe cardiovascular health in African Americans and to highlight unique considerations for disease prevention and management.

METHOD

The primary sources of information were identified with PubMed/Medline and online sources from the Centers for Disease Control and Prevention.

RESULTS

The higher prevalence of traditional cardiovascular risk factors (eg, hypertension, diabetes mellitus, obesity, and atherosclerotic cardiovascular risk) underlies the relatively earlier age of onset of cardiovascular diseases among African Americans. Hypertension in particular is highly prevalent among African Americans and contributes directly to the notable disparities in stroke, heart failure, and peripheral artery disease among African Americans. Despite the availability of effective pharmacotherapies and indications for some tailored pharmacotherapies for African Americans (eg, heart failure medications), disease management is less effective among African Americans, yielding higher mortality. Explanations for these persistent disparities in cardiovascular disease are multifactorial and span from the individual level to the social environment.

CONCLUSIONS

The strategies needed to promote equity in the cardiovascular health of African Americans require input from a broad set of stakeholders, including clinicians and researchers from across multiple disciplines.

Thyroid Function, Cardiovascular Risk Factors, and Incident Atherosclerotic Cardiovascular Disease: The Atherosclerosis Risk in Communities (ARIC) Study

CONTEXT

Cardiovascular outcomes in mild thyroid dysfunction (treatment controversial) and moderate or severe dysfunction (treatment standard) remain uncertain.

OBJECTIVE

To examine cross-sectional and prospective associations of thyroid function with cardiovascular risk factors and events.

DESIGN

In the Atherosclerosis Risk in Communities Study, we measured concentrations of thyrotropin, free thyroxine, and total triiodothyronine (T3) in stored serum samples originally collected in 1990-1992. We used multivariable linear regression to assess cross-sectional associations of thyroid function with cardiovascular risk factors and Cox regression to assess prospective associations with cardiovascular events. Follow-up occurred through 31 December 2014.

SETTING

General community.

PARTICIPANTS

Black and white men and women from the United States, without prior myocardial infarction (MI), stroke, or heart failure.

MAIN OUTCOMES AND MEASURES

Cross-sectional outcomes were blood pressure, glycemic markers, and blood lipids. Prospective outcomes were adjudicated fatal and nonfatal MI and stroke.

RESULTS

Among 11,359 participants (57 ± 6 years, 58% women), thyroid function was more strongly associated with blood lipids than blood pressure or glycemic measures. Mean adjusted differences in low-density lipoprotein cholesterol were +15.1 (95% confidence interval: 10.5 to 19.7) and +3.2 (0.0 to 6.4) mg/dL in those with moderate/severe and mild chemical hypothyroidism, relative to euthyroidism; an opposite pattern was seen in hyperthyroidism. Similar differences were seen in triglycerides and non-high-density lipoprotein cholesterol. With a 22.5-year median follow-up, 1102 MIs and 838 strokes occurred, with similar outcomes among baseline thyroid function groups and by T3 concentrations.

CONCLUSIONS

Hypothyroidism is associated with hyperlipidemia, but the magnitude is small in mild chemical hypothyroidism, and cardiovascular outcomes are similar between thyroid function groups.

Blood Pressure and Risk of Cardiovascular Events in Patients on Chronic Hemodialysis: The CRIC Study (Chronic Renal Insufficiency Cohort)

We recently reported a linear association between higher systolic blood pressure (SBP) and risk of mortality in hemodialysis patients when SBP is measured outside of the dialysis unit (out-of-dialysis-unit-SBP), despite there being a U-shaped association between SBP measured at the dialysis unit (dialysis-unit-SBP) with risk of mortality. Here, we explored the relationship between SBP with cardiovascular events, which has important treatment implications but has not been well elucidated. Among 383 hemodialysis participants enrolled in the prospective CRIC study (Chronic Renal Insufficiency Cohort), multivariable splines and Cox models were used to study the association between SBP and adjudicated cardiovascular events (heart failure, myocardial infarction, ischemic stroke, and peripheral artery disease), controlling for differences in demographics, cardiovascular disease risk factors, and dialysis parameters. Dialysis-unit-SBP and out-of-dialysis-unit-SBP were modestly correlated (r=0.34; P<0.001). We noted a U-shaped association of dialysis-unit-SBP and risk of cardiovascular events, with the nadir risk between 140 and 170 mm Hg. In contrast, there was a linear stepwise association between out-of-dialysis-unit-SBP with risk of cardiovascular events. Participants with out-of-dialysis-unit-SBP ≥128 mm Hg (top 2 quartiles) had >2-fold increased risk of cardiovascular events compared with those with out-of-dialysis-unit-SBP ≤112 mm Hg (3rd SBP quartile: adjusted hazard ratio, 2.08 [95% confidence interval, 1.12-3.87] and fourth SBP quartile: adjusted hazard ratio, 2.76 [95% confidence interval, 1.42-5.33]). In conclusion, among hemodialysis patients, although there is a U-shaped (paradoxical) association of dialysis-unit-SBP and risk of cardiovascular disease, there is a linear association of out-of-dialysis-unit-SBP with risk of cardiovascular disease. Out-of-dialysis-unit blood pressure provides key information and may be an important therapeutic target.

Abnormal P-Wave Axis and Ischemic Stroke: The ARIC Study (Atherosclerosis Risk In Communities)

BACKGROUND AND PURPOSE

Abnormal P-wave axis (aPWA) has been linked to incident atrial fibrillation and mortality; however, the relationship between aPWA and stroke has not been reported. We hypothesized that aPWA is associated with ischemic stroke independent of atrial fibrillation and other stroke risk factors and tested our hypothesis in the ARIC study (Atherosclerosis Risk In Communities), a community-based prospective cohort study.

METHODS

We included 15 102 participants (aged 54.2±5.7 years; 55.2% women; 26.5% blacks) who attended the baseline examination (1987-1989) and without prevalent stroke. We defined aPWA as any value outside 0 to 75° using 12-lead ECGs obtained during study visits. Each case of incident ischemic stroke was classified in accordance with criteria from the National Survey of Stroke by a computer algorithm and adjudicated by physician review. Multivariable Cox regression was used to estimate hazard ratios and 95% confidence intervals for the association of aPWA with stroke.

RESULTS

During a mean follow-up of 20.2 years, there were 657 incident ischemic stroke cases. aPWA was independently associated with a 1.50-fold (95% confidence interval, 1.22-1.85) increased risk of ischemic stroke in the multivariable model that included atrial fibrillation. When subtyped, aPWA was associated with a 2.04-fold (95% confidence interval, 1.42-2.95) increased risk of cardioembolic stroke and a 1.32-fold (95% confidence interval, 1.03-1.71) increased risk of thrombotic stroke.

CONCLUSIONS

aPWA is independently associated with ischemic stroke. This association seems to be stronger for cardioembolic strokes. Collectively, our findings suggest that alterations in atrial electric activation may predispose to cardiac thromboembolism independent of atrial fibrillation.

Correlates of Dementia and Mild Cognitive Impairment in Patients With Atrial Fibrillation: The Atherosclerosis Risk in Communities Neurocognitive Study (ARIC-NCS)

BACKGROUND

Atrial fibrillation (AF) has been associated with faster cognitive decline and increased dementia risk. Factors associated with dementia in patients with AF have been seldom studied.

METHODS AND RESULTS

We studied 6432 individuals from the ARIC-NCS (Atherosclerosis Risk in Communities Neurocognitive Study). In 2011 to 2013, participants underwent a physical exam, echocardiography, detailed cognitive assessments, and a subset, brain magnetic resonance imaging. Dementia and mild cognitive impairment (MCI), as well as etiology of MCI/dementia, Alzheimer's disease-related or vascular, were adjudicated by an expert panel. AF was defined by study ECGs and past hospitalizations. We used logistic regression to estimate odds ratios and 95% CI of MCI/dementia by AF status and to assess cross-sectional correlates of MCI/dementia in patients with AF. Among 6432 participants, 611 (9.5%) had prevalent AF. AF was associated with increased odds of dementia and MCI (odds ratio, 95% CI, 2.25, 1.64-3.10, and 1.28, 1.04-1.56, respectively). Prevalence of Alzheimer's disease-related MCI/dementia and vascular MCI/dementia were higher in participants with AF than without AF (odds ratio, 95% CI, 1.29, 1.04-1.61, and 1.50, 0.99-2.25, respectively). In multivariable analyses, older age, lower body mass index, diabetes mellitus, stroke, and APOE genotype were associated with dementia prevalence in participants with AF. In models evaluating MCI/dementia subtypes, diabetes mellitus was associated with Alzheimer's disease-related MCI/dementia, whereas male sex and stroke were risk factors for vascular MCI/dementia.

CONCLUSIONS

In a large, community-based study, AF was associated with higher prevalence of MCI and dementia. Controlling cardiometabolic risk factors is a potential target for prevention of adverse cognitive outcomes in AF patients.