Moderate alcohol consumption on the risk of stroke in the Million Veteran Program

BACKGROUND

There is inconsistent evidence on the association of moderate alcohol consumption and stroke risk in the general population and is not well studied among U.S. Veterans. Furthermore, it is unclear whether primarily drinking beer, wine, or liquor is associated with a difference in stroke risk.

METHODS

The study included 185,323 Million Veteran Program participants who self-reported alcohol consumption on the Lifestyle Survey. Moderate consumption was defined as 1-2 drinks/day and beverage preference of beer, wine or liquor was defined if ≥ 50% of total drinks consumed were from a single type of beverage. Strokes were defined using ICD-9 and ICD-10 codes from the participants' electronic health record.

RESULTS

The mean (sd) age of the sample was 64 (13) years and 11% were women. We observed 4,339 (94% ischemic; 6% hemorrhagic) strokes over a median follow-up of 5.2 years. In Cox models adjusted for age, sex, race, education, income, body mass index, smoking, exercise, diet, cholesterol, prevalent diabetes, prevalent hypertension, lipid-lowering medication, antihypertensive medication, and diabetes medication, moderate alcohol consumption (1-2 drinks/day) was associated with a 22% lower risk of total stroke compared with never drinking [Hazards ratio (HR) 95% confidence interval (CI): 0.78 (0.67, 0.92)]. When stratifying by stroke type, we observed a similar protective association with moderate consumption and ischemic stroke [HR (95% CI): 0.76 (0.65, 0.90)], but a non-statistically significant higher risk of hemorrhagic stroke [HR (95% CI): 1.29 (0.64, 2.61)]. We did not observe a difference in ischemic or hemorrhagic stroke risk among those who preferred beer, liquor or wine vs. no beverage preference. When stratifying by prior number of hospital visits (≤ 15, 16-33, 34-64, ≥ 65) as a proxy for health status, we observed attenuation of the protective association with greater number of visits [HR (95% CI): 0.87 (0.63, 1.19) for ≥ 65 visits vs. 0.80 (0.59, 1.08) for ≤ 15 visits].

CONCLUSIONS

We observed a lower risk of ischemic stroke, but not hemorrhagic stroke with moderate alcohol consumption and did not observe substantial differences in risk by beverage preference among a sample of U.S. Veterans. Healthy user bias of moderate alcohol consumption may be driving some of the observed protective association.

Plant-based diets and the incidence of cardiovascular disease: the Million Veteran Program

Background

A healthful plant-based diet was associated with lower risks of coronary heart disease and type 2 diabetes, and a favourable profile of adiposity-associated biomarkers, while an unhealthful plant-based diet was associated with elevated risk of cardiometabolic disease in health professional populations. However, little is known about the associations between plant-based dietary patterns and risk of cardiovascular disease (CVD) in US veterans.

Methods

The study population consisted of 148 506 participants who were free of diabetes, CVD and cancer at baseline in the Veterans Affairs (VA) Million Veteran Program. Diet was assessed using a Food Frequency Questionnaire at baseline. We calculated an overall Plant-Based Diet Index (PDI), a healthful PDI (hPDI) and an unhealthful PDI (uPDI). The CVD endpoints included non-fatal myocardial infarction (MI) and acute ischaemic stroke (AIS) identified through high-throughput phenotyping algorithms approach and fatal CVD events identified by searching the National Death Index.

Results

With up to 8 years of follow-up, we documented 5025 CVD cases. After adjustment for confounding factors, a higher PDI was significantly associated with a lower risk of CVD (HR comparing extreme quintiles=0.75, 95% CI 0.68 to 0.82, P trend<0.0001). We observed an inverse association between hPDI and the risk of CVD (HR comparing extreme quintiles=0.71, 95% CI 0.64 to 0.78, P trend<0.001), whereas uPDI was positively associated with the risk of CVD (HR comparing extreme quintiles=1.12, 95% CI 1.02 to 1.24, P trend<0.001). We found similar associations of hPDI with subtypes of CVD; a 10-unit increment in hPDI was associated with HRs (95% CI) of 0.81 (0.75 to 0.87) for fatal CVD, 0.86 (0.79 to 0.94) for non-fatal MI and 0.86 (0.78 to 0.95) for non-fatal AIS.

Conclusions

Plant-based dietary pattern enriched with healthier plant foods was associated with a substantially lower CVD risk in US veterans.

Serum Cholesterol and Impact of Age on Coronary Heart Disease Death in More Than 4 Million Veterans

Background The lipid hypothesis postulates that lower blood cholesterol is associated with reduced coronary heart disease (CHD) risk, which has been challenged by reports of a U-shaped relation between cholesterol and death in recent studies. We sought to examine whether the U-shaped relationship is true and to assess the impact of age on this association. Method and Results We conducted a prospective cohort study of 4 467 942 veterans aged >18 years, with baseline outpatient visits from 2002 to 2007 and follow-up to December 30, 2018, in the Veterans Health Administration electronic health record system. We observed a J-shaped relation between total cholesterol (TC) and CHD mortality after a comprehensive adjustment of confounding factors: flat for TC <180 mg/dL, and greater risk was present at higher cholesterol levels. Compared with veterans with TC between 180 and 199 mg/dL, the multiadjusted hazard ratios (HRs) for CHD death were 1.03 (95% CI, 1.02-1.04), 1.07 (95% CI, 1.06-1.09), 1.15 (95% CI, 1.13-1.18), 1.25 (95% CI, 1.22-1.28), and 1.45 (95% CI, 1.42-1.49) times greater among veterans with TC (mg/dL) of 200 to 219, 220 to 239, 140 to 259, 260 to 279 and ≥280, respectively. Similar J-shaped TC-CHD mortality patterns were observed among veterans with and without statin use at or before baseline. Conclusions The cholesterol paradox, for example, higher CHD death in patients with a low cholesterol level, was a reflection of reverse causality, especially among older participants. Our results support the lipid hypothesis that lower blood cholesterol is associated with reduced CHD. Furthermore, the hypothesis remained true when TC was low due to use of statins or other lipid-lowering medication.

Metabolomic Signatures of Sedentary Behavior and Cardiometabolic Traits in US Hispanics/Latinos: Results from HCHS/SOL

PURPOSE

The aim of this study was to understand the serum metabolomic signatures of moderate-to-vigorous physical activity (MVPA) and sedentary behavior, and further associate their metabolomic signatures with incident cardiometabolic diseases.

METHODS

This analysis included 2711 US Hispanics/Latinos from the Hispanic Community Health Study/Study of Latinos (HCHS/SOL) aged 18-74 yr (2008-2011). An untargeted, liquid chromatography-mass spectrometry was used to profile the serum metabolome. The associations of metabolites with accelerometer-measured MVPA and sedentary time were examined using survey linear regressions adjusting for covariates. The weighted correlation network analysis identified modules of correlated metabolites in relation to sedentary time, and the modules were associated with incident diabetes, dyslipidemia, and hypertension over the 6-yr follow-up.

RESULTS

Of 624 metabolites, 5 and 102 were associated with MVPA and sedentary behavior at false discovery rate (FDR) <0.05, respectively, after adjusting for socioeconomic and lifestyle factors. The weighted correlation network analysis identified 8 modules from 102 metabolites associated with sedentary time. Four modules (branched-chain amino acids, erythritol, polyunsaturated fatty acid, creatine) were positively, and the other four (acyl choline, plasmalogen glycerol phosphatidyl choline, plasmalogen glycerol phosphatidyl ethanolamine, urea cycle) were negatively correlated with sedentary time. Among these modules, a higher branched-chain amino acid score and a lower plasmalogen glycerol phosphatidyl choline score were associated with increased risks of diabetes and dyslipidemia. A higher erythritol score was associated with an increased risk of diabetes, and a lower acyl choline score was linked to an increased risk of hypertension.

CONCLUSIONS

In this study of US Hispanics/Latinos, we identified multiple serum metabolomic signatures of sedentary behavior and their associations with risk of incident diabetes, hypertension, and dyslipidemia. These findings suggest a potential role of circulating metabolites in the links between sedentary behavior and cardiometabolic diseases.

Characterizing longitudinal change in accelerometry-based moderate-to-vigorous physical activity in the Hispanic Community Health Study/Study of Latinos and the Framingham Heart Study

BACKGROUND

Physical activity promotes health and is particularly important during middle and older age for decreasing morbidity and mortality. We assessed the correlates of changes over time in moderate-to-vigorous physical activity (MVPA) in Hispanic/Latino adults from the Hispanic Community Health Study/Study of Latinos (HCHS/SOL: mean [SD] age 49.2 y [11.5]) and compared them to a cohort of primarily White adults from the Framingham Heart Study (FHS: mean [SD] 46.9 y [9.2]).

METHODS

Between 2008 and 2019, we assessed accelerometry-based MVPA at two time points with an average follow-up of: 7.6 y, SD 1.3 for HCHS/SOL, and 7.8 y, SD 0.7 for FHS. We used multinomial logistic regression to relate socio-demographic and health behaviors with changes in compliance with 2018 US recommendations for MVPA from time 1 to time 2 (remained active or inactive; became active or inactive) across the two cohorts.

RESULTS

In HCHS/SOL mean MVPA was 22.6 (SD, 23.8) minutes at time 1 and dropped to 16.7 (19.0) minutes at time 2. In FHS Mean MVPA was 21.7 min (SD, 17.7) at time 1 and dropped to 21.3 min (SD, 19.2) at time 2. Across both cohorts, odds of meeting MVPA guidelines over time were about 6% lower in individuals who had lower quality diets vs. higher, about half in older vs. younger adults, about three times lower in women vs. men, and 9% lower in individuals who had a higher vs. lower BMI at baseline. Cohorts differed in how age, gender, income, education, depressive symptoms, marital status and perception of general health and pain associated with changes in physical activity. High income older Hispanics/Latino adults were more likely to become inactive at the follow-up visit as were HCHS/SOL women who were retired and FHS participants who had lower levels of education and income. Higher depressive symptomology was associated with becoming active only in HCHS/SOL women. Being male and married was associated with becoming inactive in both cohorts. Higher perception of general health and lower perception of pain were associated with remaining active only in FHS adults.

CONCLUSIONS

These findings highlight potentially high-risk groups for targeted MVPA intervention.

Abstract P595: Low Serum Cholesterol and Coronary Heart Disease Mortality in Veterans

Background: The lipid hypothesis postulates that lower blood cholesterol is associated with reduced coronary heart disease (CHD) risk, which has been challenged by recent studies that observed a U-shaped relation between cholesterol and mortality. The effect of low cholesterol and CHD risk among Veterans is unclear.

Methods: This prospective cohort study included Veterans greater than 18 years of age with baseline outpatient visits from 2002 to 2007 and follow-up to December 30, 2018 in the Veterans Health Administration electronic health record system. Veterans were followed to assess CHD mortality risk in relation to outpatient blood cholesterol levels. We used Cox proportional hazard regression to estimate the hazard ratio (HR) and 95% confidence interval (CI) of CHD mortality associated with total cholesterol (TC).

Results: Among 4,467,942 Veterans, 381,871 CHD deaths were recorded. We observed a V-shaped relation between TC and age-, sex, race and smoking-adjusted risk of CHD mortality. The association became U-shaped after adjustment for statin use, body mass index, hypertension, and diabetes. When further adjusted for high-density lipoprotein level, 11 baseline diseases, and applying a 2-year lag analysis, the relation to CHD mortality was J-shaped--flat for TC<180 mg/dL and greater risk was present at higher cholesterol levels. Compared to Veterans with TC between 180-199 mg/dL, risk for CHD mortality (HR (95%CI)) was 1.03 (1.02-1.04), 1.07 (1.06-1.09), 1.15 (1.13-1.18), 1.25 (1.22-1.28) and 1.45 (1.42-1.49) times greater among Veterans with TC (mg/dL) of 200-219, 220-239, 140-259, 260-279 and ≥280, respectively. Transition of the TC- CHD mortality patterns were J-J-J, V-U-J and L-U-J among young, middle, and older veterans (P for interaction between TC and age group < 0.001). Similar J-shaped but weaker relations were observed in statin users at baseline.

Conclusions: Based on prospective data for almost 4.5 million adult Veterans, CHD mortality risk steadily increased for TC ≥200mg/dL after adjustment for a range of health conditions. Our results support the lipid hypothesis that lower blood cholesterol is associated with reduced CHD risk and lower prevalence of multimorbidity, mental health disorders, nutritional deficits, and other risk factors for CHD. Furthermore, the hypothesis remained true when TC was low due to use of statins or other lipid-lowering medication. The changes in risk for CHD mortality by TC groups observed in our study (L- to U- to J-shape) highlights the importance of fully adjusting for the presence of multimorbidity and HDL-C to avoid misleading conclusions.

Mild-to-Moderate Kidney Dysfunction and Cardiovascular Disease: Observational and Mendelian Randomization Analyses

BACKGROUND

End-stage renal disease is associated with a high risk of cardiovascular events. It is unknown, however, whether mild-to-moderate kidney dysfunction is causally related to coronary heart disease (CHD) and stroke.

METHODS

Observational analyses were conducted using individual-level data from 4 population data sources (Emerging Risk Factors Collaboration, EPIC-CVD [European Prospective Investigation into Cancer and Nutrition-Cardiovascular Disease Study], Million Veteran Program, and UK Biobank), comprising 648 135 participants with no history of cardiovascular disease or diabetes at baseline, yielding 42 858 and 15 693 incident CHD and stroke events, respectively, during 6.8 million person-years of follow-up. Using a genetic risk score of 218 variants for estimated glomerular filtration rate (eGFR), we conducted Mendelian randomization analyses involving 413 718 participants (25 917 CHD and 8622 strokes) in EPIC-CVD, Million Veteran Program, and UK Biobank.

RESULTS

There were U-shaped observational associations of creatinine-based eGFR with CHD and stroke, with higher risk in participants with eGFR values <60 or >105 mL·min-1·1.73 m-2, compared with those with eGFR between 60 and 105 mL·min-1·1.73 m-2. Mendelian randomization analyses for CHD showed an association among participants with eGFR <60 mL·min-1·1.73 m-2, with a 14% (95% CI, 3%-27%) higher CHD risk per 5 mL·min-1·1.73 m-2 lower genetically predicted eGFR, but not for those with eGFR >105 mL·min-1·1.73 m-2. Results were not materially different after adjustment for factors associated with the eGFR genetic risk score, such as lipoprotein(a), triglycerides, hemoglobin A1c, and blood pressure. Mendelian randomization results for stroke were nonsignificant but broadly similar to those for CHD.

CONCLUSIONS

In people without manifest cardiovascular disease or diabetes, mild-to-moderate kidney dysfunction is causally related to risk of CHD, highlighting the potential value of preventive approaches that preserve and modulate kidney function.

Temporal Trends in Incidence of Premature Cardiovascular Disease Over the Past 7 Decades: The Framingham Heart Study

Background Premature onset of cardiovascular disease (CVD) imposes a significant societal burden and challenges prevention efforts. Methods and Results Trends in the incidence of premature CVD (before age 55, 60, or 65 years, separate analysis for each threshold) were evaluated in 14 464 Framingham Heart Study participants over 7 decades of observation (1950-2019). The change in the incidence of premature CVD (per decade) in men and women was assessed using overdispersed Poisson regression (accounting for cohort effects), adjusting for age at entry and age at onset of premature CVD within each decade. CVD was defined as a composite of fatal or nonfatal coronary heart disease, stroke or transient ischemic attack, peripheral vascular disease, and heart failure. There were 2223 first CVD events (832 in women) before age 65 years during 282 481 person-years of observations (154 587 in women) between 1950 and 2019. The age-adjusted CVD incidence before age 65 years decreased from 14.8 per 1000 person-years (1950-1959) to 4.69 per 1000 person-years (2010-2019) in men and from 7.23 per 1000 person-years (1950-1959) to 1.73 per 1000 person-years (2010-2019) in women. In adjusted analyses, the incidence of premature CVD decreased per decade in men (18.4% [95% CI, 12.0%-24.0%], for onset before age 55 years; 19.5% [95% CI, 12.0%-27.0%], for onset before age 60 years; 21.3% [95% CI, 16.0%-27.0%], for onset before age 65 years) and women (15.1% [95% CI, 7.0%-22.0%], for onset before age 55 years; 14.0% [95% CI, 6.0%-22.0%], for onset before age 60 years; 18.2% [95% CI, 12.0%-24.0%], for onset before age 65 years). The decline in premature CVD was accompanied by a reduction in smoking and increased use of lipid-lowering treatments across the decades. Incidence of premature coronary heart disease decreased, whereas the contribution of stroke to premature CVD burden increased over time. Conclusions The incidence of premature CVD has decreased among White adults in the Framingham cohort over the past 70 years; the residual burden of premature stroke warrants further study. Additional studies of trends in premature CVD in more racially and geographically diverse populations are warranted to elucidate the generalizability of these findings.

Predictors of incident diabetes in two populations: framingham heart study and hispanic community health study / study of latinos

BACKGROUND

Non-genetic factors contribute to differences in diabetes risk across race/ethnic and socioeconomic groups, which raises the question of whether effects of predictors of diabetes are similar across populations. We studied diabetes incidence in the primarily non-Hispanic White Framingham Heart Study (FHS, N = 4066) and the urban, largely immigrant Hispanic Community Health Study/Study of Latinos (HCHS/SOL, N = 6891) Please check if the affiliations are captured and presented correctly.

METHODS

Clinical, behavioral, and socioeconomic characteristics were collected at in-person examinations followed by seven-day accelerometry. Among individuals without diabetes, Cox proportional hazards regression models (both age- and sex-adjusted, and then multivariable-adjusted for all candidate predictors) identified predictors of incident diabetes over a decade of follow-up, defined using clinical history or laboratory assessments.

RESULTS

Four independent predictors were shared between FHS and HCHS/SOL. In each cohort, the multivariable-adjusted hazard of diabetes increased by approximately 50% for every ten-year increment of age and every five-unit increment of body mass index (BMI), and was 50-70% higher among hypertensive than among non-hypertensive individuals (all P < 0.01). Compared with full-time employment status, the multivariable-adjusted hazard ratio (HR) and 95% confidence interval (CI) for part-time employment was 0.61 (0.37,1.00) in FHS and 0.62 (0.41,0.95) in HCHS/SOL. Moderate-to-vigorous physical activity (MVPA) was an additional predictor in common observed in age- and sex-adjusted models, which did not persist after adjustment for other covariates (compared with MVPA ≤ 5 min/day, HR for MVPA level ≥ 30 min/day was 0.48 [0.31,0.74] in FHS and 0.74 [0.56,0.97] in HCHS/SOL). Additional predictors found in sex- and age-adjusted analyses among the FHS participants included male gender and lower education, but these predictors were not found to be independent of others in multivariable adjusted models, nor were they associated with diabetes risk among HCHS/SOL adults.

CONCLUSIONS

The same four independent predictors - age, body mass index, hypertension and employment status - were associated with diabetes risk across two disparate US populations. While the reason for elevated diabetes risk in full-time workers is unclear, the findings suggest that diabetes may be part of the work-related burden of disease. Our findings also support prior evidence that differences by gender and socioeconomic position in diabetes risk are not universally present across populations.

Notable paradoxical phenomena in associations between cardiovascular health score, subclinical and clinical cardiovascular disease in the community: The Framingham Heart Study

Importance

Cardiovascular Health (CVH) scores are inversely associated with prevalent subclinical (SubDz) and incident cardiovascular disease (CVD). However, the majority of people who develop CVD have intermediate or ideal CVH scores, while many with poor CVH profiles escape CVD development.

Objective

To describe the prevalence of paradoxical relations among CVH, SubDz, and CVD.

Design

Cohort study, Framingham Study data collected prospectively (1995–2016).

Setting

Population-based.

Participants

7,627 participants (mean age 49 years, 53% women) attending Offspring examinations 6/7 and Third Generation examinations 1/2.

Exposures

CVH score (range 0–14) constructed from poor, intermediate, or ideal status for each metric (smoking, diet, physical activity, blood pressure, body mass index, fasting glucose, total cholesterol); and prevalent SubDz (≥1 of: increased carotid intimal media thickness, CIMT; left ventricular hypertrophy, LVH; microalbuminuria, MA; elevated ankle brachial index, ABI; coronary artery calcium score ≥100,CAC).

Main outcome(s) and measure(s)

Ideal CVH (scores 12–14), intermediate CVH (scores 8–11), and poor CVH (0–7). We described three distinct paradoxical phenomena, involving combinations of CVH, SubDz, and CVD, and generated CVD incidence rates and predicted CVD probabilities for all combinations.

Results

We observed 842 CVD events (median follow-up 13.7 years); 1,663 participants had SubDz. Most individuals with poor CVH (78%) or SubDz (57% for CIMT to 77% for LVH) did not develop CVD on follow-up. Among participants with incident CVD, the majority had intermediate or ideal CVH (68%) or absent SubDz (46% for CAC to 96% for ABI) at baseline. We observed similar paradoxical results in relations between CVH and prevalent SubDz. Poor CVH and prevalent SubDz were each associated with higher CVD incidence rates compared to intermediate or ideal CVH and absent SubDz, respectively. The predicted CVD probability was nearly three-times greater among participants with poor (22%) versus intermediate or ideal CVH (8%). Mean CVD predicted probabilities were nearly three (26% vs. 10% for MA) to six-times (29% vs. 5% for CAC) greater among participants with SubDz versus without SubDz. Findings were consistent within age and sex strata.

Conclusions and relevance

Although poor CVH and SubDz presence are associated with CVD incidence, paradoxical phenomena involving CVH, SubDz, and CVD are frequently prevalent in the community. Further studies to elucidate biological mechanisms underlying these phenomena are warranted.

Million Veteran Program’s response to COVID-19: Survey development and preliminary findings

Background

In response to the novel Coronavirus Disease 2019 (COVID-19) pandemic, the Department of Veterans Affairs (VA) Million Veteran Program (MVP) organized efforts to better understand the impact of COVID-19 on Veterans by developing and deploying a self-reported survey.

Methods

The MVP COVID-19 Survey was developed to collect COVID-19 specific elements including symptoms, diagnosis, hospitalization, behavioral and psychosocial factors and to augment existing MVP data with longitudinal collection of key domains in physical and mental health. Due to the rapidly evolving nature of the pandemic, a multipronged strategy was implemented to widely disseminate the COVID-19 Survey and capture data using both the online platform and mailings.

Results

We limited the findings of this paper to the initial phase of survey dissemination which began in May 2020. A total of 729,625 eligible MVP Veterans were invited to complete version 1 of the COVID-19 Survey. As of October 31, 2020, 58,159 surveys have been returned. The mean and standard deviation (SD) age of responders was 71 (11) years, 8.6% were female, 8.2% were Black, 5.6% were Hispanic, and 446 (0.8%) self-reported a COVID-19 diagnosis. Over 90% of responders reported wearing masks, practicing social distancing, and frequent hand washing.

Conclusion

The MVP COVID-19 Survey provides a systematic collection of data regarding COVID-19 behaviors among Veterans and represents one of the first large-scale, national surveillance efforts of COVID-19 in the Veteran population. Continued work will examine the overall response to the survey with comparison to available VA health record data.

Degree of Adherence to Based Diet and Total and Cause-Specific Mortality: Prospective Cohort Study in the Million Veteran Program

OBJECTIVE

To examine the associations between adherence to plant-based diets and mortality.

DESIGN

prospective study. We calculated a plant-based diet index (PDI) by assigning positive scores to plant foods and reverse scores to animal foods. We also created a healthful PDI (hPDI) and an unhealthful PDI (uPDI) by further separate the healthy plant foods from less-healthy plant foods.

SETTING

the VA Million Veteran Program.

PARTICIPANTS

315,919 men and women aged 19 to 104 years who completed a food frequency questionnaire at the baseline.

RESULTS

We documented 31,136 deaths during the follow-up. A higher PDI was significantly associated with lower total mortality [hazard ratio (HR) comparing extreme deciles =0.75, 95% confidence interval (CI): 0.71 to 0.79, Ptrend <0.001]. We observed an inverse association between hPDI and total mortality (HR comparing extreme deciles =0.64, 95% CI: 0.61 to 0.68, Ptrend <0.001), whereas uPDI was positively associated with total mortality (HR comparing extreme deciles =1.41, 95% CI: 1.33 to 1.49, Ptrend <0.001). Similar significant associations of PDI, hPDI, and uPDI were also observed for CVD and cancer mortality. The associations between the plant-based diet indices and total mortality were consistent among African and European American participants, and participants free from CVD and cancer and those who were diagnosed with major chronic disease at baseline.

CONCLUSIONS

A greater adherence to a plant-based diet was associated with substantially lower total mortality in this large population of veterans. These findings support recommending plant-rich dietary patterns for the prevention of major chronic diseases.

Prevalence, Predictors, Progression, and Prognosis of Hypertension Subtypes in the Framingham Heart Study

Background

The epidemiology of hypertension subtypes has not been well characterized in the recent era.

Methods and Results

We delineated the prevalence, predictors, progression, and prognostic significance of hypertension subtypes in 8198 Framingham Heart Study participants (mean age, 46.5 years; 54% women). The prevalence of hypertension subtypes was as follows: nonhypertensive (systolic blood pressure [SBP] <140 mm Hg and diastolic blood pressure [DBP] <90 mm Hg), 79%; isolated systolic hypertension (ISH; SBP ≥140 mm Hg and DBP <90 mm Hg), 8%; isolated diastolic hypertension (SBP <140 mm Hg and DBP ≥90 mm Hg), 4%; and systolic‐diastolic hypertension (SDH; SBP ≥140 mm Hg and DBP ≥90 mm Hg), 9%. The prevalence of ISH and SDH increased with age. Analysis of a subsample of nonhypertensive participants demonstrated that increasing age, female sex, higher heart rate, left ventricular mass, and greater left ventricular concentricity were predictors of incident ISH and SDH. Higher baseline DBP was associated with the risk of developing isolated diastolic hypertension and SDH, whereas higher SBP was associated with all 3 hypertension subtypes. On follow‐up (median, 5.5 years), isolated diastolic hypertension often reverted to nonhypertensive BP (in 42% of participants) and ISH progressed to SDH (in 26% of participants), whereas SDH frequently transitioned to ISH (in 20% of participants). During follow‐up (median, 14.6 years), 889 participants developed cardiovascular disease. Compared with the nonhypertensive group (referent), ISH (adjusted hazard ratio [HR], 1.57; 95% CI, 1.30–1.90) and SDH (HR, 1.66; 95% CI, 1.36–2.01) were associated with increased cardiovascular disease risk, whereas isolated diastolic hypertension was not (HR, 1.03; 95% CI, 0.68–1.57).

Conclusions

Hypertension subtypes vary in prevalence with age, are dynamic during short‐term follow‐up, and exhibit distinctive prognoses, underscoring the importance of blood pressure subphenotyping.

Dietary Sodium and Potassium Intake and Risk of Non-Fatal Cardiovascular Diseases: The Million Veteran Program

Objective: To examine the association between intakes of sodium and potassium and the ratio of sodium to potassium and incident myocardial infarction and stroke. Design, Setting and Participants: Prospective cohort study of 180,156 Veterans aged 19 to 107 years with plausible dietary intake measured by food frequency questionnaire (FFQ) who were free of cardiovascular disease (CVD) and cancer at baseline in the VA Million Veteran Program (MVP). Main outcome measures: CVD defined as non-fatal myocardial infarction (MI) or acute ischemic stroke (AIS) ascertained using high-throughput phenotyping algorithms applied to electronic health records. Results: During up to 8 years of follow-up, we documented 4090 CVD cases (2499 MI and 1712 AIS). After adjustment for confounding factors, a higher sodium intake was associated with a higher risk of CVD, whereas potassium intake was inversely associated with the risk of CVD [hazard ratio (HR) comparing extreme quintiles, 95% confidence interval (CI): 1.09 (95% CI: 0.99−1.21, p trend = 0.01) for sodium and 0.87 (95% CI: 0.79−0.96, p trend = 0.005) for potassium]. In addition, the ratio of sodium to potassium (Na/K ratio) was positively associated with the risk of CVD (HR comparing extreme quintiles = 1.26, 95% CI: 1.14−1.39, p trend < 0.0001). The associations of Na/K ratio were consistent for two subtypes of CVD; one standard deviation increment in the ratio was associated with HRs (95% CI) of 1.12 (1.06−1.19) for MI and 1.11 (1.03−1.19) for AIS. In secondary analyses, the observed associations were consistent across race and status for diabetes, hypertension, and high cholesterol at baseline. Associations appeared to be more pronounced among participants with poor dietary quality. Conclusions: A high sodium intake and a low potassium intake were associated with a higher risk of CVD in this large population of US veterans.

Hypertension-Mediated Organ Damage: Prevalence, Correlates, and Prognosis in the Community

BACKGROUND

Guidelines emphasize screening people with elevated BP for the presence of end-organ damage.

METHODS

We characterized the prevalence, correlates, and prognosis of hypertension-mediated organ damage (HMOD) in the community-based Framingham Study. 7898 participants (mean age 51.6 years, 54% women) underwent assessment for the following HMOD: electrocardiographic and echocardiographic left ventricular hypertrophy, abnormal brain imaging findings consistent with vascular injury, increased carotid intima-media thickness, elevated carotid-femoral pulse wave velocity, reduced kidney function, microalbuminuria, and low ankle-brachial index. We characterized HMOD prevalence according to blood pressure (BP) categories defined by four international BP guidelines. Participants were followed up for incidence of cardiovascular disease.

RESULTS

The prevalence of HMOD varied positively with systolic BP and pulse pressure but negatively with diastolic BP; it increased with age, was similar in both sexes, and varied across BP guidelines based on their thresholds defining hypertension. Among participants with hypertension, elevated carotid-femoral pulse wave velocity was the most prevalent HMOD (40%-60%), whereas low ankle-brachial index was the least prevalent (<5%). Left ventricular hypertrophy, reduced kidney function, microalbuminuria, increased carotid intima-media thickness, and abnormal brain imaging findings had an intermediate prevalence (20%-40%). HMOD frequently clustered within individuals. On follow-up (median, 14.1 years), there were 384 cardiovascular disease events among 5865 participants with concurrent assessment of left ventricular mass, carotid-femoral pulse wave velocity, kidney function, and microalbuminuria. For every BP category above optimal (referent group), the presence of HMOD increased cardiovascular disease risk compared with its absence.

CONCLUSIONS

The prevalence of HMOD varies across international BP guidelines based on their different thresholds for defining hypertension. The presence of HMOD confers incremental prognostic information regarding cardiovascular disease risk at every BP category.

Frailty and cardiovascular mortality in more than 3 million US Veterans

AIMS

Frailty is associated with an increased risk of all-cause mortality and cardiovascular (CV) events. Limited data exist from the modern era of CV prevention on the relationship between frailty and CV mortality. We hypothesized that frailty is associated with an increased risk of CV mortality.

METHODS AND RESULTS

All US Veterans aged ≥65 years who were regular users of Veteran Affairs care from 2002 to 2017 were included. Frailty was defined using a 31-item previously validated frailty index, ranging from 0 to 1. The primary outcome was CV mortality with secondary analyses examining the relationship between frailty and CV events (myocardial infarction, stroke, revascularization). Survival analysis models were adjusted for age, sex, ethnicity, geographic region, smoking, hyperlipidaemia, statin use, and blood pressure medication use. There were 3 068 439 US Veterans included in the analysis. Mean age was 74.1 ± 5.8 years in 2002, 76.0 ± 8.3 years in 2014, 98% male, and 87.5% White. In 2002, the median (interquartile range) frailty score was 0.16 (0.10-0.23). This increased and stabilized to 0.19 (0.10-0.32) for 2006-14. The presence of frailty was associated with an increased risk of CV mortality at every stage of frailty. Frailty was associated with an increased risk of myocardial infarction and stroke, but not revascularization.

CONCLUSION

In this population, both the presence and severity of frailty are tightly correlated with CV death, independent of underlying CV disease. This study is the largest and most contemporary evaluation of the relationship between frailty and CV mortality to date. Further work is needed to understand how this risk can be diminished.

KEY QUESTION

Can an electronic frailty index identify adults aged 65 and older who are at risk of CV mortality and major CV events?

KEY FINDING

Among 3 068 439 US Veterans aged 65 and older, frailty was associated with an increased risk of CV mortality at every level of frailty. Frailty was also associated with an increased risk of myocardial infarction and stroke, but not revascularization.

TAKE HOME MESSAGE

Both the presence and severity of frailty are associated with CV mortality and major CV events, independent of underlying CV disease.

Aortic Root Diameter and Arterial Stiffness: Conjoint Relations to the Incidence of Cardiovascular Disease in the Framingham Heart Study

[Figure: see text].

Association of Estimated Cardiorespiratory Fitness in Midlife With Cardiometabolic Outcomes and Mortality

IMPORTANCE

The associations of estimated cardiorespiratory fitness (eCRF) during midlife with subclinical atherosclerosis, arterial stiffness, incident cardiometabolic disease, and mortality are not well understood.

OBJECTIVE

To examine associations of midlife eCRF with subclinical atherosclerosis, arterial stiffness, incident cardiometabolic disease, and mortality.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study included 2962 participants in the Framingham Study Second Generation (conducted between 1979 and 2001). Data were analyzed from January 2020 to June 2020.

EXPOSURES

eCRF was calculated using sex-specific algorithms (including age, body mass index, waist circumference, physical activity, resting heart rate, and smoking) and was categorized as: (1) tertiles of standardized eCRF at examination cycle 7 (1998 to 2001); (2) tertiles of standardized average eCRF between examination cycles 2 and 7 (1979 to 2001); and (3) eCRF trajectories between examination cycles 2 and 7, with the lowest tertile or trajectory (ie, low eCRF) as referent group.

MAIN OUTCOMES AND MEASURES

Subclinical atherosclerosis (carotid intima-media thickness [CIMT], coronary artery calcium [CAC] score); arterial stiffness (carotid-femoral pulse wave velocity [-1000/CFPWV]); incident hypertension, diabetes, chronic kidney disease (CKD), cardiovascular disease (CVD), and mortality after examination cycle 7.

RESULTS

A total of 2962 participants were included in this cohort study (mean [SD] age, 61.5 [9.2] years; 1562 [52.7%] women). The number of events or participants at risk after examination cycle 7 (at a mean follow-up of 15 years) was 728 of 1506 for hypertension, 214 of 2268 for diabetes, 439 of 2343 for CKD, 500 of 2608 for CVD, and 770 of 2962 for mortality. Compared with the low eCRF reference value, high single examination eCRF was associated with lower CFPWV (β [SE], -11.13 [1.33] ms/m) and CIMT (β [SE], -0.12 [0.05] mm), and lower risk of hypertension (hazard ratio [HR], 0.63; 95% CI, 0.46-0.85), diabetes (HR, 0.38; 95% CI, 0.23-0.62), and CVD (HR, 0.71; 95% CI, 0.53-0.95), although it was not associated with CKD or mortality. Similarly, compared with the low eCRF reference, high eCRF trajectories and mean eCRF were associated with lower CFPWV (β [SE], -11.85 [1.89] ms/m and -10.36 [1.54] ms/m), CIMT (β [SE], -0.19 [0.06] mm and -0.15 [0.05] mm), CAC scores (β [SE], -0.67 [0.25] AU and -0.63 [0.20] AU), and lower risk of hypertension (HR, 0.54; 95% CI, 0.34-0.87 and HR, 0.48; 95% CI, 0.34-0.68), diabetes (HR, 0.27; 95% CI, 0.15-0.48 and HR, 0.31; 95% CI, 0.18-0.54), CKD (HR, 0.63; 95% CI, 0.40-0.97 and HR, 0.64; 95% CI, 0.44-0.94), and CVD (HR, 0.46; 95% CI, 0.31-0.68 and HR, 0.43; 95% CI, 0.30-0.60). Compared with the reference value, a high eCRF trajectory was associated with lower risk of mortality (HR, 0.69; 95% CI, 0.50-0.95).

CONCLUSIONS AND RELEVANCE

In this cohort study, higher midlife eCRF was associated with lower burdens of subclinical atherosclerosis and vascular stiffness, and with a lower risk of hypertension, diabetes, chronic kidney disease, cardiovascular disease, and mortality. These findings suggest that midlife eCRF may serve as a prognostic marker for subclinical atherosclerosis, arterial stiffness, cardiometabolic health, and mortality in later life.

Association of Mildly Reduced Kidney Function With Cardiovascular Disease: The Framingham Heart Study

Background Data are limited on the association of mildly reduced estimated glomerular filtration rate (eGFR 60-89 mL/min per 1.73 m²) with cardiovascular disease (CVD) in the community. Methods and Results We evaluated 3066 Framingham Offspring Study participants (55% women, mean age 58 years), without clinical CVD. Using multivariable regression, we related categories of mildly reduced eGFR (80-89, 70-79, or 60-69 versus ≥90 mL/min per 1.73 m² [referent]) to prevalent coronary artery calcium, carotid intima media thickness, and left ventricular hypertrophy, and to circulating concentrations of cardiac stress biomarkers. We related eGFR categories to CVD incidence and to progression to ≥Stage 3 chronic kidney disease (eGFR <60 mL/min per 1.73 m²) using Cox regression. Individuals with eGFR 60-69 mL/min per 1.73 m² (n=320) had higher coronary artery calcium score (odds ratio 1.69; 95% CI 1.02-2.80) compared with the referent group. Individuals with eGFR 60-69 and 70-79 mL/min per 1.73 m² had higher blood growth differentiating factor-15 concentrations (β=0.131 and 0.058 per unit-increase in log-biomarker, respectively). Participants with eGFR 60-69 and 80-89 mL/min per 1.73 m² had higher blood B-type natriuretic peptide concentrations (β=0.119 and 0.116, respectively). On follow-up (median 16 years; 691 incident CVD and 252 chronic kidney disease events), individuals with eGFR 60-69 and 70-79 mL/min per 1.73 m² experienced higher CVD incidence (hazard ratio [HR], 1.40; 95% CI, 1.02-1.93 and 1.45, 95% CI, 1.05-2.00, respectively, versus referent). Participants with eGFR 60-69 mL/min per 1.73 m² experienced higher chronic kidney disease incidence (HR, 2.94; 95% CI, 1.80-4.78 versus referent). Conclusions Individuals with mildly reduced eGFR 60-69 mL/min per 1.73 m² have a higher burden of subclinical atherosclerosis cross-sectionally, and a greater risk of CVD and chronic kidney disease progression prospectively. Additional studies are warranted to confirm our findings.

Abstract 009: Incremental Predictive Utility Of Subclinical Disease Measures For Cardiovascular Disease Risk

Introduction: The Framingham Risk Score (FRS) has been widely used to predict cardiovascular disease (CVD) risk. However, a comparison of the incremental prognostic utility of different subclinical disease (SubDz) measures is not clear.

Methods: We evaluated participants aged 40-79 years (mean age 55 years, 56% women) from the Framingham Offspring (Exam 8, 2005-2008) and Third Generation cohorts (Exam 1, 2002-2005), free of CVD and diabetes, with data on coronary artery calcium (CAC, n=2497), and two measures of target organ damage: urine albumin-to-creatinine ratio (UACR, n=4011) and left ventricular mass (LVM, n=3770). We categorized FRS: <10%, 10-19%, and ≥20% and defined high CAC as CAC≥100, microalbuminuria (MA) as UACR ≥25mg/g in men and ≥35mg/g in women, and left ventricular hypertrophy (LVH) as LVM/body surface area>115 g/m 2 (men) and >95g/m 2 (women). We created 6 cross-classified groups: FRS <10%-No SubDz; FRS <10% + SubDz; FRS 10-19%-No SubDz; FRS 10-19% + SubDz; FRS ≥20%-No SubDz; and FRS ≥20% + SubDz. We related the groups to CVD risk using Cox regression adjusting for age, sex, and cohort and plotted Kaplan-Meier curves to display CVD cumulative incidence by each SubDz cross-classified group.

Results: Over a median follow-up of 12 years, 7% of participants developed CVD. Comparing FRS 10-19%-No SubDz and FRS 10-19% + SubDz to FRS <10%-No SubDz (referent), we observed hazards ratios (95% CI) for CVD of 1.68 (0.99-2.83) and 6.50 (3.64-11.61) for high CAC; 1.33 (0.95-1.85) and 2.15 (1.10-4.18) for MA; and 1.43 (0.99-2.07) and 2.18 (1.33-3.57) for LVH. Each SubDz measure predicted CVD risk incrementally over the FRS. In a sub-sample with all three SubDz measures, the model c-statistic with FRS only was 0.725, increasing to 0.773, 0.726, and 0.728 when adding CAC, MA, and LVH, respectively.

Conclusion: Presence of a high CAC score outperformed other measures of target organ damage (MA or LVH) for predicting CVD risk, regardless of FRS. Additional studies of larger multi-ethnic samples are warranted to confirm our findings.

Phenome-wide association of 1809 phenotypes and COVID-19 disease progression in the Veterans Health Administration Million Veteran Program

BACKGROUND

The risk factors associated with the stages of Coronavirus Disease-2019 (COVID-19) disease progression are not well known. We aim to identify risk factors specific to each state of COVID-19 progression from SARS-CoV-2 infection through death.

METHODS AND RESULTS

We included 648,202 participants from the Veteran Affairs Million Veteran Program (2011-). We identified characteristics and 1,809 ICD code-based phenotypes from the electronic health record. We used logistic regression to examine the association of age, sex, body mass index (BMI), race, and prevalent phenotypes to the stages of COVID-19 disease progression: infection, hospitalization, intensive care unit (ICU) admission, and 30-day mortality (separate models for each). Models were adjusted for age, sex, race, ethnicity, number of visit months and ICD codes, state infection rate and controlled for multiple testing using false discovery rate (≤0.1). As of August 10, 2020, 5,929 individuals were SARS-CoV-2 positive and among those, 1,463 (25%) were hospitalized, 579 (10%) were in ICU, and 398 (7%) died. We observed a lower risk in women vs. men for ICU and mortality (Odds Ratio (95% CI): 0.48 (0.30-0.76) and 0.59 (0.31-1.15), respectively) and a higher risk in Black vs. Other race patients for hospitalization and ICU (OR (95%CI): 1.53 (1.32-1.77) and 1.63 (1.32-2.02), respectively). We observed an increased risk of all COVID-19 disease states with older age and BMI ≥35 vs. 20-24 kg/m2. Renal failure, respiratory failure, morbid obesity, acid-base balance disorder, white blood cell diseases, hydronephrosis and bacterial infections were associated with an increased risk of ICU admissions; sepsis, chronic skin ulcers, acid-base balance disorder and acidosis were associated with mortality.

CONCLUSIONS

Older age, higher BMI, males and patients with a history of respiratory, kidney, bacterial or metabolic comorbidities experienced greater COVID-19 severity. Future studies to investigate the underlying mechanisms associated with these phenotype clusters and COVID-19 are warranted.

Association of Blood Pressure and Heart Rate Responses to Submaximal Exercise With Incident Heart Failure: The Framingham Heart Study

Background Exercise stress tests are conventionally performed to assess risk of coronary artery disease. Using the FHS (Framingham Heart Study) Offspring cohort, we related blood pressure (BP) and heart rate responses during and after submaximal exercise to the incidence of heart failure (HF). Methods and Results We evaluated Framingham Offspring Study participants (n=2066; mean age, 58 years; 53% women) who completed 2 stages of an exercise test (Bruce protocol) at their seventh examination (1998-2002). We measured pulse pressure, systolic BP, diastolic BP, and heart rate responses during stage 2 exercise (2.5 mph at 12% grade). We calculated the changes in systolic BP, diastolic BP, and heart rate from stage 2 to recovery 3 minutes after exercise. We used Cox proportional hazards regression to relate each standardized exercise variable (during stage 2, and at 3 minutes of recovery) individually to HF incidence, adjusting for standard risk factors. On follow-up (median, 16.8 years), 85 participants developed new-onset HF. Higher exercise diastolic BP was associated with higher HF with reduced ejection fraction (ejection fraction <50%) risk (hazard ratio [HR] per SD increment, 1.26; 95% CI, 1.01-1.59). Lower stage 2 pulse pressure and rapid postexercise recovery of heart rate and systolic BP were associated with higher HF with reduced ejection fraction risk (HR per SD increment, 0.73 [95% CI, 0.57-0.94]; 0.52 [95% CI, 0.35-0.76]; and 0.63 [95% CI, 0.47-0.84], respectively). BP and heart rate responses to submaximal exercise were not associated with risk of HF with preserved ejection fraction (ejection fraction ≥50%). Conclusions Accentuated diastolic BP during exercise with slower systolic BP and heart rate recovery after exercise are markers of HF with reduced ejection fraction risk.

Racial and Ethnic Disparities in U.S. Veteran Health Characteristics

Racial/ethnic health disparities persist among veterans despite comparable access and quality of care. We describe racial/ethnic differences in self-reported health characteristics among 437,413 men and women (mean age (SD) = 64.5 (12.6), 91% men, 79% White) within the Million Veteran Program. The Cochran-Mantel-Haenszel test and linear mixed models were used to compare age-standardized frequencies and means across race/ethnicity groups, stratified by gender. Black, Hispanic, and Other race men and women reported worse self-rated health, greater VA healthcare utilization, and more combat exposure than Whites. Compared to White men, Black and Other men reported more circulatory, musculoskeletal, mental health, and infectious disease conditions while Hispanic men reported fewer circulatory and more mental health, infectious disease, kidney, and neurological conditions. Compared to White women, Black women reported more circulatory and infectious disease conditions and Other women reported more infectious disease conditions. Smoking rates were higher among Black men, but lower for other minority groups compared to Whites. Minority groups were less likely to drink alcohol and had lower physical fitness than Whites. By identifying differences in burden of various health conditions and risk factors across different racial/ethnic groups, our findings can inform future studies and ultimately interventions addressing disparities.

Circulating growth factors and cardiac remodeling in the community: The Framingham Heart Study

BACKGROUND AND AIMS

Cardiac and vascular growth factors (GF) may influence myocardial remodeling through cardiac growth and angiogenic effects. We hypothesized that concentrations of circulating GF are associated with cardiac remodeling traits.

METHODS

We related blood concentrations of vascular endothelial GF (VEGF), VEGFR-1 (sFlt1), angiopoietin 2 (Ang-2), soluble angiopoietin type-2 receptor (sTie2), hepatocyte GF (HGF), insulin-like GF (IGF)-1, IGF binding protein (IGFBP)-3, and growth differentiation factor-15 (GDF-15) to echocardiographic traits in 3151 Framingham Study participants (mean age 40 years, 55% women). We evaluated the following measures: left ventricular (LV) mass index (LVMi), LV ejection fraction (LVEF), global longitudinal strain (GLS), mitral E/e', and aortic root diameter (AoR). All biomarker values were sex-standardized.

RESULTS

In multivariable-adjusted analyses, higher GDF-15 concentrations were associated with higher log-LVMi (β = 0.009 per SD, P = 0.01). Similarly, sTie2 concentrations were positively associated with log-E/e' (β = 0.011 per SD, P = 0.04). IGF-1 and Ang-2 concentrations were positively and negatively associated with GLS, respectively (β_IGF-1 = 0.16 per SD and β_Ang-2 = -0.15 per SD, both P < 0.05), whereas higher sFlt1 and Ang-2 levels were associated with smaller log-AoR (β_sFlt1 = -0.004 per SD and β _Ang-2 = -0.005 per SD, respectively; P < 0.05).

CONCLUSION

In our large community-based sample, we observed patterns of associations between several circulating vascular GF and cardiac remodeling indices that are consistent with the known biological effects of these pro- and anti-angiogenic factors on the myocardium and conduit arteries. Additional studies are warranted to replicate our findings and assess their prognostic significance.

Premature Parental Cardiovascular Disease and Subclinical Disease Burden in the Offspring

Background Offspring of parents with premature cardiovascular disease (CVD) have an increased risk of developing subclinical and clinical CVD. It is unclear whether this association differs by vascular beds in the offspring or by the age cut points used to define premature parental CVD. Methods and Results Using 3 generations of Framingham Heart Study participants, we assessed prevalent coronary artery calcification, the progression of coronary artery calcification over 6.1 years (median), carotid intima media thickness and the ankle-brachial index in 1046 offspring of parents with premature CVD before age 70 years, in 1618 offspring with both parents free of CVD and in 923 offspring with parents with CVD after age 70 years. We used different age cut points (55, 60, 65, and 70 years) to define premature parental CVD. In multivariable-adjusted models, offspring of parents with premature CVD (onset before age 65 years) displayed greater odds for prevalent coronary artery calcification (odds ratio [OR], 1.81; 95% CI, 1.35-2.43), higher carotid intima media thickness (OR, 1.50; 95% CI, 0.92-2.44) and lower ankle-brachial index (OR, 1.89; 95% CI, 1.00-3.58). These associations were generally consistent across different age cut points used to define premature parental CVD. The association with the progression of coronary artery calcification was less consistent. Conclusions Parental premature CVD is associated with increased subclinical CVD burden in the offspring, with consistent relations across different vascular beds and for different age cut points used to define premature parental CVD. Future studies should evaluate whether screening for subclinical CVD traits is warranted in offspring with premature parental CVD.

Familial Clustering of Aortic Size, Aneurysms, and Dissections in the Community

Background:

Ruptured aortic aneurysm and aortic dissections are potentially preventable disorders associated with high mortality. Screening of individuals at risk may translate into elective surgical interventions and lowered mortality. It is uncertain if the risk of aortic dilation of varying degrees aggregates within families.

Methods:

We investigated the risk of having thoracic and abdominal aortic sizes in the highest quartile (measured by computed tomography scans and indexed for body size) if at least 1 parent did so in the Framingham Heart Study cohorts, and estimated the incidence rates and hazard ratios of developing aortic aneurysm or dissection among first-degree relatives of those with aortic aneurysm or dissection, in comparison with age- and sex-matched controls (1:10 for aortic aneurysm and 1:100 for aortic dissection) using the Danish nationwide administrative registries.

Results:

In the Framingham Heart Study, offspring (n=235) whose parent(s) had a sex- and age-standardized aortic size in the upper quartile had a multivariable-adjusted ≈3-fold increased odds ratio of belonging to the upper quartile themselves. In Denmark, a total of 68 939 individuals (mean age, 42 years) had a first-degree relative with aortic aneurysm and 7209 persons (mean age, 39 years) had a first-degree relative with aortic dissection. During an average follow-up of 7 years, first-degree relatives of patients with aortic aneurysm and dissection had a hazard ratio of 6.70 (95% CI, 5.96–7.52) for developing aortic aneurysm and a hazard ratio of 9.24 (95% CI, 5.53–15.44) for dissection in comparison with matched controls. These estimates remained unchanged on adjusting for several comorbidities, including prevalent hypertension, bicuspid aortic valve, and the Marfan syndrome. For both aortic aneurysm and dissections, the absolute event rates approached 1 per 1000 person-years for first-degree relatives versus 11 to 13 (aortic aneurysm) and 2 to 3 (aortic dissections) per 100 000 person-years among controls.

Conclusions:

Increased aortic size, a precursor of aortic aneurysm and a risk factor for dissection, clusters in families. The incidence rates of aortic aneurysm and dissections approach the incidence rates of other common cardiovascular conditions in first-degree relatives, supporting the use of systematic screening for these conditions.

Association of Circulating Tissue Inhibitor of Metalloproteinases-1 and Procollagen Type III Aminoterminal Peptide Levels With Incident Heart Failure and Chronic Kidney Disease

Background Tissue inhibitor of metalloproteinases-1 ( TIMP -1) and procollagen type III aminoterminal peptide are established circulating markers of extracellular matrix remodeling and associated with cardiovascular disease. The association of both biomarkers with incident congestive heart failure and chronic kidney disease ( CKD ) in the community is not well studied. Methods and Results We measured plasma total TIMP -1 and procollagen type III aminoterminal peptide levels in 922 Framingham participants (mean age, 57 years; 57% women) and related both biomarkers to the risk of incident CKD and congestive heart failure in multivariable-adjusted Cox regression models. Plasma total TIMP -1 levels were positively associated with risk of incident CKD (164 events; hazard ratio per 1 SD in log-biomarker, 1.90; 95% CI , 1.53-2.37) in multivariable models, including adjustments for left ventricular mass, C-reactive protein, and B-type natriuretic peptide levels. The association of total TIMP -1 with risk of congestive heart failure was statistically significant in an age- and sex-adjusted model, but was attenuated upon adjustment for conventional risk factors. Blood procollagen type III aminoterminal peptide levels were not related to the risk of CKD or congestive heart failure. Conclusions Higher baseline levels of total TIMP -1 conferred an increased risk for incident CKD , independent of conventional risk factors and circulating biomarkers of chronic systemic inflammation and neurohormonal activation. Our prospective observations in a large community-based sample support the role of matrix remodeling in the pathogenesis of CKD .

Plant-Based Diet and the Risk of Cardiovascular Disease and Mortality: The Million Veteran Program

Objectives

Although prior studies have found inverse associations of plant-based diets with the risk of coronary heart disease, the results for stroke and total mortality are inconsistent. Little is known about the associations between a plant-based diet and cardiovascular health in US Veterans. We aim to prospectively examine the associations between the adherence to a plant-based diet and the incidence of myocardial infarction (MI), acute ischemic stroke (AIS) and total mortality.

Methods

We included 181,359 participants who were free of cardiovascular disease and cancer at baseline from the Million Veteran Program. Diet was assessed using a food frequency questionnaire at baseline. We calculated a plant-based diet index (PDI) by assigning positive scores to plant foods and reverse scores to animal foods. We calculated hazard ratios (HRs) and 95% confident intervals (CIs) by comparing participants in each quintile with those in the lowest quintile of the PDI. We used electronic health records to identify incident MI and AIS cases. Information on mortality was obtained from systematic searches of the National Death Index.

Results

Over 717,857 person-years of follow-up (mean follow-up: 4 years), we documented 1467 incident MI cases, 1253 AIS cases, and 5609 deaths. After adjustment for age, sex, body mass index (BMI), total energy intake, race/ethnicity, smoking, physical activity, alcohol use, educational level, socioeconomic status and baseline histories of diabetes, hypercholesterolemia and hypertension, a higher PDI was associated with significantly lower mortality (HR comparing extreme quintiles: 0.87, 95% CI: 0.78–0.96, Ptrend = 0.006). Participants with a greater adherence to a plant-based diet experienced lower risk of incident MI and AIS (HRs comparing extreme quintiles: 0.79, 95% CI: 0.64–0.97, Ptrend = 0.02 for MI; 0.69, 95% CI: 0.55–0.85, Ptrend = 0.005 for AIS). The associations of PDI with mortality, MI and AIS were consistent across different subgroups defined by sex, age, smoking, BMI, diabetes, hypertension and hypercholesterolemia, as well as between white and African American participants.

Conclusions

A greater adherence to a plant-based diet is associated with substantially lower risk of cardiovascular disease and total mortality in this large population of Veterans.

Funding Sources

US Department of Veterans Affairs.

Association of Cardiorespiratory Fitness and Hemodynamic Responses to Submaximal Exercise Testing With the Incidence of Chronic Kidney Disease: The Framingham Heart Study

OBJECTIVE

To relate cardiorespiratory fitness (CRF) and hemodynamic responses to exercise to the incidence of chronic kidney disease (CKD).

METHODS

We evaluated 2715 Framingham Offspring Study participants followed up (mean, 24.8 years) after their second examination (1979-1983) until the end of their ninth examination (2011-2014). Participants (mean age, 43 years; 1397 women [51.5%]) without prevalent CKD or cardiovascular disease at baseline were included. We examined the associations of CRF and hemodynamic response to exercise with incident CKD using multivariable Cox proportional hazards regression with discrete intervals.

RESULTS

Compared with low CRF (first tertile), participants with moderate (second tertile) or high (third tertile) CRF had a lower risk of CKD (hazard ratios [95% CIs]: 0.74 [0.61-0.91] and 0.73 [0.59-0.91], respectively). Participants with chronotropic incompetence (hazard ratio, 1.38 [95% CI, 1.06 to 1.79]), higher exercise systolic blood pressure (hazard ratio per SD, 1.20 [95% CI, 1.07 to 1.34]), and impaired heart rate recovery (hazard ratio, 1.51 [95% CI, 1.08 to 2.10]) had a higher risk of CKD compared with those with chronotropic competence, lower exercise systolic blood pressure, and normal heart rate recovery, respectively. These associations remained robust when the exercise variables were mutually adjusted for. The third tertile of a standardized exercise test score comprising the statistically significant variables was associated with a higher risk of CKD compared with the first tertile (hazard ratio, 1.85; 95% CI, 1.45 to 2.36).

CONCLUSION

Higher CRF and favorable hemodynamic responses to submaximal exercise in young adulthood may be markers of lower risk of CKD in later life.

Proteomic and Metabolomic Correlates of Healthy Dietary Patterns: The Framingham Heart Study

Data on proteomic and metabolomic signatures of healthy dietary patterns are limited. We evaluated the cross-sectional association of serum proteomic and metabolomic markers with three dietary patterns: the Alternative Healthy Eating Index (AHEI), the Dietary Approaches to Stop Hypertension (DASH) diet; and a Mediterranean-style (MDS) diet. We examined participants from the Framingham Offspring Study (mean age; 55 years; 52% women) who had complete proteomic (n = 1713) and metabolomic (n = 2284) data; using food frequency questionnaires to derive dietary pattern indices. Proteins and metabolites were quantified using the SomaScan platform and liquid chromatography/tandem mass spectrometry; respectively. We used multivariable-adjusted linear regression models to relate each dietary pattern index (independent variables) to each proteomic and metabolomic marker (dependent variables). Of the 1373 proteins; 103 were associated with at least one dietary pattern (48 with AHEI; 83 with DASH; and 8 with MDS; all false discovery rate [FDR] ≤ 0.05). We identified unique associations between dietary patterns and proteins (17 with AHEI; 52 with DASH; and 3 with MDS; all FDR ≤ 0.05). Significant proteins enriched biological pathways involved in cellular metabolism/proliferation and immune response/inflammation. Of the 216 metabolites; 65 were associated with at least one dietary pattern (38 with AHEI; 43 with DASH; and 50 with MDS; all FDR ≤ 0.05). All three dietary patterns were associated with a common signature of 24 metabolites (63% lipids). Proteins and metabolites associated with dietary patterns may help characterize intermediate phenotypes that provide insights into the molecular mechanisms mediating diet-related disease. Our findings warrant replication in independent populations.

Association of subclinical atherosclerosis with echocardiographic indices of cardiac remodeling: The Framingham Study

Background

It is well established that coronary artery disease progresses along with myocardial disease. However, data on the association between coronary artery calcium (CAC) and echocardiographic variables are lacking.

Methods and results

Among 2,650 Framingham Study participants (mean age 51 yrs, 48% women; 40% with CAC>0), we related CT-based CAC score to left ventricular (LV) mass index (LVMi), LV ejection fraction (LVEF), E/e’, global longitudinal strain (GLS), left atrial emptying fraction (LAEF), and aortic root diameter (AoR), using multivariable-adjusted generalized linear models. CAC score (independent variable) was used as log-transformed continuous [ln(CAC+1)] and as a categorical (0, 1–100, and ≥101) variable. Adjusting for standard risk factors, higher CAC score was associated with higher LVMi and AoR (β_LVMI per 1-SD increase 0.012, β_AoR 0.008; P<0.05, for both). Participants with 1≤CAC≤100 and those with CAC≥101 had higher AoR (β_AoR 0.013 and 0.020, respectively, P = 0.01) than those with CAC = 0. CAC score was not significantly associated with LVEF, E/e’, GLS or LAEF. Age modified the association of CAC score with AoR; higher CAC scores were associated with larger AoR more strongly in older (>58 years; β_AoR0.0042;P<0.007) than in younger (≤58 years) participants (β_AoR0.0027;P<0.03).

Conclusions

We observed that subclinical atherosclerosis was associated with ventricular and aortic remodeling. The prognostic significance of these associations warrants evaluation in additional mechanistic studies.

Diabetes Mellitus-Related All-Cause and Cardiovascular Mortality in a National Cohort of Adults

Background Diabetes mellitus is a risk factor for cardiovascular disease ( CVD ) and has been associated with 2- to 4-fold higher mortality. Diabetes mellitus-related mortality has not been reassessed in individuals receiving routine care in the United States in the contemporary era of CVD risk reduction. Methods and Results We retrospectively studied 963 648 adults receiving care in the US Veterans Affairs Healthcare System from 2002 to 2014; mean follow-up was 8 years. We estimated associations of diabetes mellitus status and hemoglobin A1c (HbA1c) with all-cause and CVD mortality using covariate-adjusted incidence rates and multivariable Cox proportional hazards regression. Of participants, 34% had diabetes mellitus. Compared with nondiabetic individuals, patients with diabetes mellitus had 7.0 (95% CI , 6.7-7.4) and 3.5 (95% CI, 3.3-3.7) deaths/1000-person-years higher all-cause and CVD mortality, respectively. The age-, sex-, race-, and ethnicity-adjusted hazard ratio for diabetes mellitus-related mortality was 1.29 (95% CI, 1.28-1.31), and declined with adjustment for CVD risk factors (hazard ratio, 1.18 [95% CI, 1.16-1.19]) and glycemia (hazard ratio, 1.03 [95% CI, 1.02-1.05]). Among individuals with diabetes mellitus, CVD mortality increased as HbA1c exceeded 7% (hazard ratios, 1.11 [95% CI, 1.08-1.14], 1.25 [95% CI, 1.22-1.29], and 1.52 [95% CI, 1.48-1.56] for HbA1c 7%-7.9%, 8%-8.9%, and ≥9%, respectively, relative to HbA1c 6%-6.9%). HbA1c 6% to 6.9% was associated with the lowest mortality risk irrespective of CVD history or age. Conclusions Diabetes mellitus remains significantly associated with all-cause and CVD mortality, although diabetes mellitus-related excess mortality is lower in the contemporary era than previously. We observed a gradient of mortality risk with increasing HbA1c >6% to 6.9%, suggesting HbA1c remains an informative predictor of outcomes even if causality cannot be inferred.

Left Ventricular Mass and Incident Chronic Kidney Disease

Chronic kidney disease (CKD) is associated with incident cardiovascular morbidity and mortality. Whether subclinical cardiovascular disease and target organ damage is associated with incident CKD is unknown. We investigated the relations of echocardiographic left ventricular mass (LVM) with incident CKD. We evaluated 2258 Framingham Offspring cohort participants (mean age, 57 years; 56% women) who underwent echocardiography at a routine examination and had an estimated glomerular filtration rate ≥60 mL/min per 1.73 m². We used Cox proportional hazards regression with discrete time intervals to relate sex-standardized LVM (independent variable) to the incidence of CKD, defined as estimated glomerular filtration rate <60 L/min per 1.73 m², on follow-up. During a median follow-up of 14.6 years, 373 (16.5%) participants developed incident CKD. Higher LVM was associated with higher risk of CKD after adjusting for prevalent cardiovascular disease, body mass index, systolic blood pressure, total and HDL (high-density lipoprotein) cholesterol, antihypertensive medication, smoking, and diabetes mellitus (hazard ratio, 1.15 [95% CI, 1.03-1.29]; P=0.017) per 1-SD increase in LVM g/m². Further adjustment for baseline estimated glomerular filtration rate (adjusted hazard ratio, 1.16 [95% CI, 1.04-1.31]; P=0.010) and baseline urine albumin/creatinine ratio (adjusted hazard ratio, 1.18 [95% CI, 1.04-1.33]; P=0.009) slightly attenuated the association. In our community-based sample, LVM was associated with incident CKD prospectively, which suggests that the relations between CKD and subclinical cardiovascular disease may be bidirectional. Further studies are needed to confirm our findings.

Gender Differences in Demographic and Health Characteristics of the Million Veteran Program Cohort

BACKGROUND

The Department of Veterans Affairs Million Veteran Program (MVP) is the largest ongoing cohort program of its kind, with 654,903 enrollees as of June 2018. The objectives of this study were to examine gender differences in the MVP cohort with respect to response and enrollment rates; demographic, health, and health care characteristics; and prevalence of self-reported health conditions.

METHODS

The MVP Baseline Survey was completed by 415,694 veterans (8% women), providing self-report measures of demographic characteristics, health status, and medical history.

RESULTS

Relative to men, women demonstrated a higher positive responder rate (23.0% vs. 16.0%), slightly higher enrollment rate (13.5% vs. 12.9%), and, among enrollees, a lower survey completion rate (59.7% vs. 63.8%). Women were younger, more racially diverse, had higher educational attainment, and were less likely to be married or cohabitating with a partner than men. Women were more likely to report good to excellent health status but poorer physical fitness, and less likely to report lifetime smoking and drinking than men. Compared with men, women veterans showed an increased prevalence of musculoskeletal conditions, thyroid problems, gastrointestinal conditions, migraine headaches, and mental health disorders, as well as a decreased prevalence of gout, cardiovascular diseases, high cholesterol, diabetes, and hearing problems.

CONCLUSIONS

These results revealed some substantial gender differences in the research participation rates, demographic profile, health characteristics, and prevalence of health conditions for veterans in the MVP cohort. Findings highlight the need for tailoring recruitment efforts to ensure representation of the increasing women veteran population receiving care through the Veterans Health Administration.

Association of statin therapy with incidence of type 2 diabetes among US Veterans

Aims

While some but not all trial data have suggested an elevated risk of type 2 diabetes with statin use, limited data are available on the relation of statin treatment with glycaemia and risk of type 2 diabetes among Veterans. We examined whether statin use was associated with a higher incidence of type 2 diabetes and secondarily, if statin use was associated with high plasma glucose.

Methods

Prospective analysis based on electronic health records of 3,390,799 US Veterans from 2000 to 2012. We used the Veteran Administration Corporate Data Warehouse to obtain information on random plasma glucose. Statin use was captured using the pharmacy database. type 2 diabetes was defined as having at least one inpatient diagnosis or at least two outpatient diagnoses of type 2 diabetes using International Classification of Disease version 9 codes 250.xx, or the use of hypoglycemic agents. We used multi-level derived propensity score and inverse probability weighting to address confounding by indication and Cox regression to estimate relative risk of type 2 diabetes.

Results

The mean age was 62±11.9 years; 93.3% were men and 82.7% were white. During a median follow-up of 3.0 years, 443,104 new cases of type 2 diabetes occurred. Compared to no statin use, multivariable adjusted hazard ratio (95% CI) for type 2 diabetes was 1.21 (1.19-1.24) for low statin potency, 1.22 (1.21-1.23) for medium statin potency, and 1.34 (1.32-1.36) for high statin potency (p linear trend <0.0001). In secondary analysis, statin use was not associated with higher plasma glucose.

Conclusions

Our data show a positive association between statin use and incidence of type 2 diabetes among US Veterans.

Perceived Stress and Fecundability: A Preconception Cohort Study of North American Couples

While some epidemiologic studies support the hypothesis that stress can adversely affect fertility, few prospective studies have assessed the association in couples from the general population. We used data from Pregnancy Study Online, a web-based preconception cohort study of pregnancy planners from the United States and Canada (2013-2018), to examine the association between women's and men's perceived stress levels prior to conception and fecundability. Women (aged 21-45 years) and their male partners (aged ≥21 years) who were attempting conception without fertility treatment were eligible. We measured perceived stress using the 10-item Perceived Stress Scale (PSS). We ascertained pregnancy information using bimonthly follow-up questionnaires of female participants. We followed 4,769 couples until self-reported pregnancy, initiation of fertility treatment, loss to follow-up, or 12 menstrual cycles of attempt time, whichever came first. We used proportional probabilities regression models to estimate fecundability ratios and 95% confidence intervals, adjusting for potential confounders. Higher PSS scores among the women were associated with slight reductions in fecundability (comparing PSS scores of ≥25 vs. <10, fecundability ratio = 0.87, 95% confidence interval: 0.74, 1.02). PSS scores among the men were not substantially associated with fecundability.

A phenotyping algorithm to identify acute ischemic stroke accurately from a national biobank: the Million Veteran Program

Background

Large databases provide an efficient way to analyze patient data. A challenge with these databases is the inconsistency of ICD codes and a potential for inaccurate ascertainment of cases. The purpose of this study was to develop and validate a reliable protocol to identify cases of acute ischemic stroke (AIS) from a large national database.

Methods

Using the national Veterans Affairs electronic health-record system, Center for Medicare and Medicaid Services, and National Death Index data, we developed an algorithm to identify cases of AIS. Using a combination of inpatient and outpatient ICD9 codes, we selected cases of AIS and controls from 1992 to 2014. Diagnoses determined after medical-chart review were considered the gold standard. We used a machine-learning algorithm and a neural network approach to identify AIS from ICD9 codes and electronic health-record information and compared it with a previous rule-based stroke-classification algorithm.

Results

We reviewed administrative hospital data, ICD9 codes, and medical records of 268 patients in detail. Compared with the gold standard, this AIS algorithm had a sensitivity of 91%, specificity of 95%, and positive predictive value of 88%. A total of 80,508 highly likely cases of AIS were identified using the algorithm in the Veterans Affairs national cardiovascular disease-risk cohort (n=2,114,458).

Conclusion

Our algorithm had high specificity for identifying AIS in a nationwide electronic health-record system. This approach may be utilized in other electronic health databases to accurately identify patients with AIS.

Baseline Characterization and Annual Trends of Body Mass Index for a Mega-Biobank Cohort of US Veterans 2011-2017

AIM

Million Veteran Program (MVP) is the largest ongoing mega-cohort biobank program in the US with 570,131 enrollees as of May 2017. The primary aim is to describe demographics, military service, and major diseases and comorbidities of the MVP cohort. Our secondary aim is to examine body mass index (BMI), a proxy for general health, among enrollees.

MATERIALS AND METHOD

The study population consists of Veterans who actively use the Veterans Health Administration in the US. Data evaluated in this paper combine health information from multiple sources to provide the most comprehensive demographic profile and information on height and weight of MVP enrollees. A standardized cleaning algorithm was used to curate the demographic variables for each participant in MVP. For height and weight, we derived a final data point for each participant to evaluate BMI.

STATISTICAL ANALYSIS USED

Multivariable logistic regression was used to compare the differences in BMI categories across enrollment years adjusting for gender, race, and age. P < 0.05 was considered statistically significant. All analyses were conducted using Statistical Analysis System 9.2.

RESULTS

The MVP cohort consists of 90.4% of males with an average age of 61.9 years (standard deviation [SD] = 13.9). MVP is the largest multiethnic biobank cohort within the Veteran population with 73.9% White, 19.0% Black, and 6.5% Hispanic. The most common self-reported disease was hypertension (62.6%) for males and depression (47.5%) for females. Mean BMI was 29.7 kg/m² (SD = 5.8) with 38.2% obese and 42.3% overweight.

CONCLUSIONS

Our findings suggest that demographic representation in MVP is similar to the Veterans Health Administration population and contrasts with the overall National Health and Nutrition Examination Survey US population. The prevalence of overweight and obese is high among US Veterans, and future studies will examine the role of BMI and disease risk in the Veteran population.

Molecularly cloned SHIV-1157ipd3N4: a highly replication- competent, mucosally transmissible R5 simian-human immunodeficiency virus encoding HIV clade C Env

Human immunodeficiency virus type 1 (HIV-1) clade C causes >50% of all HIV infections worldwide, and an estimated 90% of all transmissions occur mucosally with R5 strains. A pathogenic R5 simian-human immunodeficiency virus (SHIV) encoding HIV clade C env is highly desirable to evaluate candidate AIDS vaccines in nonhuman primates. To this end, we generated SHIV-1157i, a molecular clone from a Zambian infant isolate that carries HIV clade C env. SHIV-1157i was adapted by serial passage in five monkeys, three of which developed peripheral CD4(+) T-cell depletion. After the first inoculated monkey developed AIDS at week 137 postinoculation, transfer of its infected blood to a naïve animal induced memory T-cell depletion and thrombocytopenia within 3 months in the recipient. In parallel, genomic DNA from the blood donor was amplified to generate the late proviral clone SHIV-1157ipd3. To increase the replicative capacity of SHIV-1157ipd3, an extra NF-kappaB binding site was engineered into its 3' long terminal repeat, giving rise to SHIV-1157ipd3N4. This virus was exclusively R5 tropic and replicated more potently in rhesus peripheral blood mononuclear cells than SHIV-1157ipd3 in the presence of tumor necrosis factor alpha. Rhesus macaques of Indian and Chinese origin were next inoculated intrarectally with SHIV-1157ipd3N4; this virus replicated vigorously in both sets of monkeys. We conclude that SHIV-1157ipd3N4 is a highly replication-competent, mucosally transmissible R5 SHIV that represents a valuable tool to test candidate AIDS vaccines targeting HIV-1 clade C Env.

Antibodies: can they protect against HIV infection?

More than 20 million people have died since the discovery of human immunodeficiency virus (HIV), yet a broadly reactive AIDS vaccine remains elusive. Neutralizing antibody (nAb) response-based vaccine strategies were the first to be tested; however, when the difficulty in neutralizing primary HIV isolates was recognized, vaccine development focused instead on generating cytotoxic T-lymphocyte (CTL) responses. Recently, interest in anti-HIV nAbs has been revived by the impressive protection achieved in primates given passive immunization with neutralizing monoclonal antibodies (nmAbs) isolated from HIV clade B-infected individuals. The nmAbs used in these studies target conserved, functionally important epitopes in HIV gp120 and gp41. Regimens involving combinations of such human nmAbs or high-dose single-agent nmAb protected monkeys against intravenous (iv) and mucosal challenges with simian-human immunodeficiency virus (SHIV) strains encoding X4, X4R5 or R5 HIV env genes. In several such studies, sterilizing immunity was achieved, thus providing proof-of-concept that nAbs targeting conserved epitopes can be fully protective. The existence of these broadly reactive nmAbs suggests that it may be possible to design immunogens capable of inducing similar nAb responses by active vaccination. Unraveling the three-dimensional structures involved in the nmAb-HIV Env epitope interactions may facilitate the future development of a potent AIDS vaccine. This review is focused on the importance of nAbs in protecting against HIV infection or in containing viral spread, with particular emphasis on the successful use of nmAbs in passive immunization studies. The implications of the data from these studies on AIDS vaccine design in general are also discussed.

Remaining small bowel length: association with catheter sepsis in patients receiving home total parenteral nutrition: evidence of bacterial translocation

Patients with short bowel syndrome (SBS) receiving total parenteral nutrition (TPN) have a high incidence of catheter-related sepsis, one of its major complications. The aim of this study was to correlate the length of remaining small bowel (RSB) with septic episodes related to the central venous catheter in a group of patients with severe SBS with home TPN. The length of the RSB (<50 cm or > or = 50 cm) was related to the frequency of catheter sepsis, time until the first episode, and the agents responsible in eight SBS patients receiving home TPN. There were 13 episodes of catheter infection (0.88 per patient-year). The group with a shorter RSB length (five patients) presented 1.3 to 2.76 infections/year and 2 to 9 months until the first episode, compared to 0 to 0.75 infections/ year (p = 0.0357) and 11 to 65 months until the first episode (p = 0.0332) in the group with the longer RSB. In the first group, the agents isolated were Enterobacteriae (Enterobacter sp., Klebsiella sp., Pseudomonas sp., and Proteus sp.) in eight episodes and Candida sp. in one. In the latter sepsis was caused by Staphylococcus sp. in three episodes and Pseudomonas sp. in one. Therefore patients with remaining small bowel shorter than 50 cm have a higher frequency of catheter-related sepsis, particularly by enteric microorganisms. This might be an evidence of the occurrence of bacterial translocation and its role in the pathogenesis of catheter-related sepsis in patients with an extremely short RSB receiving home TPN.

Nitrogen dioxide in indoor ice skating facilities: an international survey

An international survey of nitrogen dioxide (NO2) levels inside indoor ice skating facilities was conducted. One-week average NO2 concentrations were measured inside and outside of 332 ice rinks located in nine countries. Each rink manager also completed a questionnaire describing the building, the resurfacing machines, and their use patterns. The (arithmetic) mean NO2 level for all rinks in the study was 228 ppb, with a range of 1-2,680 ppb, based on a sample collected at breathing height and adjacent to the ice surface. The mean of the second indoor sample (collected at a spectator's area) was 221 ppb, with a range of 1-3,175 ppb. The ratio of the indoor to outdoor NO2 concentrations was above 1 for 95% of the rinks sampled, indicating the presence of an indoor NO2 source (mean indoor:outdoor ratio = 20). Estimates of short-term NO2 concentrations indicated that as many as 40% of the sampled rinks would have exceeded the World Health Organization 1-hour guideline value of 213 ppb NO2 for indoor air. Statistically significant associations were observed between NO2 levels and the type of fuel used to power the resurfacer, the absence of a catalytic converter on a resurfacer, and the use of an ice edger. There were also indications that decreased use of mechanical ventilation, increased number of resurfacing operations per day, and smaller rink volumes were associated with increased NO2 levels. In rinks where the main resurfacer was powered by propane, the NO2 concentrations were higher than in those with gasoline-powered resurfacers, while the latter had NO2 concentrations higher than in those using diesel. Rinks where the main resurfacer was electric had the lowest indoor NO2 concentrations, similar to the levels measured outdoors.