@article {1509, title = {Brain abnormalities in the elderly: frequency and predictors in the United States (the Cardiovascular Health Study). Cardiovascular Health Study Collaborative Research Group.}, journal = {J Neural Transm Suppl}, volume = {53}, year = {1998}, month = {1998}, pages = {9-16}, abstract = {

PURPOSE: Characterize brain abnormalities in elderly people using cranial magnetic resonance imaging (MRI).

METHODS: Comprehensive lists of people 65 years and older living in the United States of America were used to obtain a representative sample of 5,888 community-dwelling participants who underwent extensive standardized evaluations. A subset of 3,660 underwent MRI. Without clinical information, neuroradiologists evaluated each scan.

RESULTS: Enlarged ventricles and sulci and prominent white matter changes were relatively common, even in a subset of the healthiest participants. Infarcts 3 mm or greater were present in 31\% of all participants and 28\% of those without a history of stroke. Most infarcts were clinically silent, small, and in the basal ganglia. Among those without a history of stroke, white matter changes were common but mostly of a mild degree. These changes were independently related to greater age, silent stroke, higher systolic blood pressure, lower forced expiratory volume in one second and income less than $50,000 per year. Changes were also associated with dysfunction, especially of cognition and the lower extremities.

CONCLUSION: MRI abnormalities are common in elderly people. Cautious interpretation is appropriate because participants are healthier than the general population and the study{\textquoteright}s design is cross-sectional.

}, keywords = {Aged, Brain, Brain Diseases, Cerebral Infarction, Cerebrovascular Disorders, Humans, Magnetic Resonance Imaging, United States}, issn = {0303-6995}, author = {Longstreth, W T} } @article {917, title = {Blood pressure level and outcomes in adults aged 65 and older with prior ischemic stroke.}, journal = {J Am Geriatr Soc}, volume = {54}, year = {2006}, month = {2006 Sep}, pages = {1309-16}, abstract = {

OBJECTIVES: To examine the association between blood pressure (BP) levels and long-term stroke outcomes in elderly stroke survivors.

DESIGN: Observational study.

SETTING: The Cardiovascular Health Study (CHS) of 5,888 community-dwelling adults.

PARTICIPANTS: Two hundred fifty-four adults aged 65 and older (mean age 78.6) who sustained a nonfatal first ischemic stroke.

MEASUREMENTS: BP levels assessed at prestroke and poststroke CHS visits were examined as predictors of stroke recurrence, coronary heart disease (CHD), combined vascular events (CVEs), and mortality.

RESULTS: Higher poststroke BP level, assessed 261.6 days (mean) after stroke, was associated with higher risk of stroke recurrence over 5.4 years (mean) of follow-up. The multivariate-adjusted hazard ratio for stroke recurrence was 1.42 (95\% confidence interval (CI) = 1.03-1.99) per standard deviation (SD) of systolic BP (P = .04) and 1.39 (95\% CI = 1.01-1.91) per SD of diastolic BP (P = .04). Mortality was significantly greater in patients with low or high poststroke BP than in those with intermediate BP. Poststroke BP was not associated with risk of CHD or CVE, although further analyses suggested that high systolic BP predicted CHD and CVE in younger but not older subjects. Prestroke BP did not predict poststroke outcomes.

CONCLUSION: In this observational study of adults aged 65 and older assessed approximately 8 months after stroke, low BP was associated with favorable risk of recurrent stroke, although high and low poststroke BP levels were associated with greater mortality. Long-term antihypertensive trials in older stroke survivors would increase knowledge about the benefits of lowering BP in this population.

}, keywords = {Aged, Aged, 80 and over, Blood Pressure, Brain Ischemia, Female, Follow-Up Studies, Humans, Male, Outcome Assessment, Health Care, Prospective Studies, Recurrence, Stroke, Survival Rate}, issn = {0002-8614}, doi = {10.1111/j.1532-5415.2006.00838.x}, author = {Kaplan, Robert C and Tirschwell, David L and Longstreth, W T and Manolio, Teri A and Heckbert, Susan R and LeValley, Aaron J and Lefkowitz, David and El-Saed, Aiman and Psaty, Bruce M} } @article {1027, title = {Biomarkers of Inflammation and MRI-Defined Small Vessel Disease of the Brain: The Cardiovascular Health Study.}, journal = {Stroke}, volume = {39}, year = {2008}, month = {2008 Jul}, pages = {1952-9}, abstract = {

BACKGROUND AND PURPOSE: To clarify the role of inflammation in the pathogenesis of small vessel disease of the brain, we investigated the association between common variation in the C-reactive protein (CRP) and interleukin (IL)-6 genes, plasma CRP and IL6 levels, and presence of MRI-defined white matter lesions (WML) and brain infarcts (BI) in elderly participants of the Cardiovascular Health Study.

METHODS: Tag single nucleotide polymorphisms (SNPs) in the CRP and IL6 genes were selected from the SeattleSNPs database. In cross-sectional analyses, logistic regression models adjusting for known cardiovascular disease risk factors were constructed to assess the associations of plasma CRP and IL6 levels and common CRP and IL6 gene haplotypes with presence of WML or BI in Blacks (n=532) and Whites (n=2905).

RESULTS: Plasma IL6 and CRP levels were associated with presence of WML and BI in both races. In Whites, common haplotypes of the IL6 gene were significantly associated with WML and BI. The common haplotype tagged by the -174G/C promoter polymorphism was associated with an increased risk of WML (OR=1.14; 95\% CI: [1.02; 1.28]). The common haplotype tagged by the -572G/C promoter polymorphism was associated with an increased risk of BI (OR=1.57; 95\% CI: [1.15; 2.14]). Significant associations were lacking for WML or BI with IL6 gene variation in Blacks, or with CRP gene variation in either race.

CONCLUSIONS: This study provides evidence of a genetic basis underlying the relationship between plasma biomarkers of inflammation and small vessel disease of the brain. Further studies to elucidate the specific role of IL6 in disease pathogenesis are warranted.

}, keywords = {African Continental Ancestry Group, Aged, Biomarkers, Brain Infarction, C-Reactive Protein, Cohort Studies, European Continental Ancestry Group, Female, Haplotypes, Humans, Inflammation, Interleukin-6, Magnetic Resonance Imaging, Male, Polymorphism, Single Nucleotide}, issn = {1524-4628}, doi = {10.1161/STROKEAHA.107.508135}, author = {Fornage, Myriam and Chiang, Y Aron and O{\textquoteright}Meara, Ellen S and Psaty, Bruce M and Reiner, Alexander P and Siscovick, David S and Tracy, Russell P and Longstreth, W T} } @article {6001, title = {Blood pressure variability and the risk of all-cause mortality, incident myocardial infarction, and incident stroke in the cardiovascular health study.}, journal = {Am J Hypertens}, volume = {26}, year = {2013}, month = {2013 Oct}, pages = {1210-7}, abstract = {

BACKGROUND: Recent reports have linked variability in visit-to-visit systolic blood pressure (SBP) to risk of mortality and stroke, independent of the effect of mean SBP level. This study aimed to evaluate whether variability in SBP is associated with all-cause mortality, incident myocardial infarction (MI), and incident stroke, independent of mean SBP or trends in SBP levels over time.

METHODS: The Cardiovascular Health Study is a longitudinal cohort study of vascular risk factors and disease in the elderly. Participants who attended their first 5 annual clinic visits and experienced no event before the 5th visit were eligible (n = 3,852). Primary analyses were restricted to participants not using antihypertensive medications throughout the first 5 clinic visits (n = 1,642). Intraindividual SBP variables were defined using each participant{\textquoteright}s 5-visit blood pressure measures. Cox proportional hazards models estimated adjusted hazard ratios (HRs) per SD increase in intraindividual SBP variability, adjusted for intraindividual SBP mean and change over time.

RESULTS: Over a mean follow-up of 9.9 years, there were 844 deaths, 203 MIs, and 195 strokes. Intraindividual SBP variability was significantly associated with increased risk of mortality (HR = 1.13; 95\% confidence interval (CI) = 1.05-1.21) and of incident MI (HR = 1.20; 95\%CI = 1.06-1.36), independent of the effect from adjustment factors. Intraindividual SBP variability was not associated with risk of stroke (HR = 1.03; 95\% CI = 0.89-1.21).

CONCLUSIONS: Long-term visit-to-visit SBP variability was independently associated with a higher risk of subsequent mortality and MI but not stroke. More research is needed to determine the relationship of BP variability with cardiovascular risk and the clinical implications.

}, keywords = {Aged, Blood Pressure, Cohort Studies, Female, Humans, Incidence, Longitudinal Studies, Male, Mortality, Myocardial Infarction, Risk, Stroke, United States}, issn = {1941-7225}, doi = {10.1093/ajh/hpt092}, author = {Suchy-Dicey, Astrid M and Wallace, Erin R and Mitchell, S V Elkind and Aguilar, Maria and Gottesman, Rebecca F and Rice, Kenneth and Kronmal, Richard and Psaty, Bruce M and Longstreth, W T} } @article {6581, title = {Brain imaging findings in elderly adults and years of life, healthy life, and able life over the ensuing 16 years: the Cardiovascular Health Study.}, journal = {J Am Geriatr Soc}, volume = {62}, year = {2014}, month = {2014 Oct}, pages = {1838-43}, abstract = {

OBJECTIVES: To determine whether elderly people with different patterns of magnetic resonance imaging (MRI) findings have different long-term outcomes.

DESIGN: Longitudinal cohort study.

SETTING: Cardiovascular Health Study.

PARTICIPANTS: Individuals aged 65 and older were recruited (N = 5,888); 3,660 of these underwent MRI, and 3,230 without a stroke before MRI were included in these analyses.

MEASUREMENTS: Cluster analysis of brain MRI findings was previously used to define five clusters: normal, atrophy, simple infarct, leukoaraiosis, and complex infarct. Participants were subsequently classified as healthy if they rated their health as excellent, very good, or good and as able if they did not report any limitations in activities of daily living (ADLs). Mean years of life (YoL), years of healthy life (YHL), and years of able life (YAL) were calculated over 16 years after the MRI and compared between clusters using unadjusted and adjusted regression analyses.

RESULTS: Mean age of participants was 75.0. With 16 years of follow-up, mean YoL was 11.3; YHL, 8.0; and YAL, 8.4. Outcomes differed significantly between clusters. With or without adjustments, outcomes were all significantly better in the normal than complex infarct cluster. The three remaining clusters had intermediate results, significantly different from the normal and complex infarct clusters but not usually from one another. Over 16 years of follow-up, participants in the complex infarct cluster (n = 368) spent the largest percentage of their 8.4 years alive being sick (38\%) and not able (38\%).

CONCLUSION: Findings on MRI scans in elderly adults are associated not only with long-term survival, but also with long-term self-rated health and limitation in ADLs. The combination of infarcts and leukoaraiosis carried the worst prognosis, presumably reflecting small vessel disease.

}, keywords = {Activities of Daily Living, Aged, Atrophy, Brain, Brain Infarction, Cohort Studies, Disability Evaluation, Female, Health Status, Humans, Leukoaraiosis, Longevity, Longitudinal Studies, Magnetic Resonance Imaging, Male, Prognosis, Regression Analysis, United States}, issn = {1532-5415}, doi = {10.1111/jgs.13068}, author = {Longstreth, W T and Diehr, Paula H and Yee, Laura M and Newman, Anne B and Beauchamp, Norman J} } @article {7466, title = {Blood Pressure and Heart Rate Measures Associated With Increased Risk of Covert Brain Infarction and Worsening Leukoaraiosis in Older Adults.}, journal = {Arterioscler Thromb Vasc Biol}, volume = {37}, year = {2017}, month = {2017 Aug}, pages = {1579-1586}, abstract = {

OBJECTIVE: In people without previous stroke, covert findings on serial magnetic resonance imaging (MRI) of incident brain infarcts and worsening leukoaraiosis are associated with increased risk for ischemic stroke and dementia. We evaluated whether various measures of blood pressure (BP) and heart rate are associated with these MRI findings.

APPROACH AND RESULTS: In the CHS (Cardiovascular Health Study), a longitudinal cohort study of older adults, we used relative risk regression to assess the associations of mean, variability, and trend in systolic BP, diastolic BP, and heart rate measured at 4 annual clinic visits between 2 brain MRIs with incident covert brain infarction and worsening white matter grade (using a 10-point scale to characterize leukoaraiosis). We included participants who had both brain MRIs, no stroke before the follow-up MRI, and no change in antihypertensive medication status during follow-up. Among 878 eligible participants, incident covert brain infarction occurred in 15\% and worsening white matter grade in 27\%. Mean systolic BP was associated with increased risk for incident covert brain infarction (relative risk per 10 mm Hg, 1.28; 95\% confidence interval, 1.12-1.47), and mean diastolic BP was associated with increased risk for worsening white matter grade (relative risk per 10 mm Hg, 1.45; 95\% confidence interval, 1.24-1.69). These findings persisted in secondary and sensitivity analyses.

CONCLUSIONS: Elevated mean systolic BP is associated with increased risk for covert brain infarction, and elevated mean diastolic BP is associated with increased risk for worsening leukoaraiosis. These findings reinforce the importance of hypertension in the development of silent cerebrovascular diseases, but the pathophysiologic relationships to BP for each may differ.

}, keywords = {Age Factors, Aged, Antihypertensive Agents, Blood Pressure, Cerebral Infarction, Disease Progression, Female, Heart Rate, Humans, Hypertension, Incidence, Leukoaraiosis, Longitudinal Studies, Magnetic Resonance Imaging, Male, Prospective Studies, Pulsatile Flow, Risk Factors, Time Factors, United States}, issn = {1524-4636}, doi = {10.1161/ATVBAHA.117.309298}, author = {Leung, Lester Y and Bartz, Traci M and Rice, Kenneth and Floyd, James and Psaty, Bruce and Gutierrez, Jose and Longstreth, W T and Mukamal, Kenneth J} } @article {8838, title = {BinomiRare: A robust test for association of a rare genetic variant with a binary outcome for mixed models and any case-control proportion.}, journal = {HGG Adv}, volume = {2}, year = {2021}, month = {2021 Jul 08}, abstract = {

Whole-genome sequencing (WGS) and whole-exome sequencing studies have become increasingly available and are being used to identify rare genetic variants associated with health and disease outcomes. Investigators routinely use mixed models to account for genetic relatedness or other clustering variables (e.g., family or household) when testing genetic associations. However, no existing tests of the association of a rare variant with a binary outcome in the presence of correlated data control the type 1 error where there are (1) few individuals harboring the rare allele, (2) a small proportion of cases relative to controls, and (3) covariates to adjust for. Here, we address all three issues in developing a framework for testing rare variant association with a binary trait in individuals harboring at least one risk allele. In this framework, we estimate outcome probabilities under the null hypothesis and then use them, within the individuals with at least one risk allele, to test variant associations. We extend the BinomiRare test, which was previously proposed for independent observations, and develop the Conway-Maxwell-Poisson (CMP) test and study their properties in simulations. We show that the BinomiRare test always controls the type 1 error, while the CMP test sometimes does not. We then use the BinomiRare test to test the association of rare genetic variants in target genes with small-vessel disease (SVD) stroke, short sleep, and venous thromboembolism (VTE), in whole-genome sequence data from the Trans-Omics for Precision Medicine (TOPMed) program.

}, issn = {2666-2477}, doi = {10.1016/j.xhgg.2021.100040}, author = {Sofer, Tamar and Lee, Jiwon and Kurniansyah, Nuzulul and Jain, Deepti and Laurie, Cecelia A and Gogarten, Stephanie M and Conomos, Matthew P and Heavner, Ben and Hu, Yao and Kooperberg, Charles and Haessler, Jeffrey and Vasan, Ramachandran S and Cupples, L Adrienne and Coombes, Brandon J and Seyerle, Amanda and Gharib, Sina A and Chen, Han and O{\textquoteright}Connell, Jeffrey R and Zhang, Man and Gottlieb, Daniel J and Psaty, Bruce M and Longstreth, W T and Rotter, Jerome I and Taylor, Kent D and Rich, Stephen S and Guo, Xiuqing and Boerwinkle, Eric and Morrison, Alanna C and Pankow, James S and Johnson, Andrew D and Pankratz, Nathan and Reiner, Alex P and Redline, Susan and Smith, Nicholas L and Rice, Kenneth M and Schifano, Elizabeth D} }