Faculty Bibliography

BACKGROUND: A previous analysis examined the contribution of endocrine disruptor exposures (endocrine-disrupting chemicals, EDCs) to adult diabetes, but was limited to effects of phthalates in middle-aged women and did not simultaneously examine multiple EDCs which are known to coexist in the environment. We therefore endeavoured to quantify potential reductions in diabetes and disease costs that could result from reducing synthetic chemical diabetogenic exposures in the elderly in Europe. METHODS: We leveraged the Prospective Investigation of the Vasculature in Uppsala Seniors (PIVUS) study ( approximately 1000 participants), which has measured exposure to phthalates; dichlorodiphenyltrichloroethylene; polychlorinated biphenyls (PCBs) and perfluoroalkyl substances to examine their independent contribution to diabetes. We estimated risk reductions assuming identical 25% reductions across levels of 4 selected compounds (PCB 153, monoethylphthalate, dichlorodiphenyldichloroethylene and perfluorononanoic acid), and diabetes costs saved in European men and women if diabetogenic exposures are limited. RESULTS: Reduction of chemical exposures was associated with a 13% (95% CI 2% to 22%) reduction in prevalent diabetes, compared with 40% resulting from an identical (25%) reduction in body mass index (BMI) in cross-sectional analyses. Extrapolating to Europe, 152 481 cases of diabetes in Europe and euro4.51 billion/year in associated costs could be prevented, compared with 469 172 cases prevented by reducing BMI. CONCLUSIONS: These findings support regulatory and individual efforts to reduce chemical exposures to reduce the burden and costs of diabetes.

Elevated blood pressure, a major risk factor for ischemic heart disease, heart failure, and stroke, is the leading global risk for mortality. Treatment and control rates are very low in low- and middle-income countries. There is an urgent need to address this problem. The Global Alliance for Chronic Diseases sponsored research projects focus on controlling hypertension, including community engagement, salt reduction, salt substitution, task redistribution, mHealth, and fixed-dose combination therapies. This paper reviews the rationale for each approach and summarizes the experience of some of the research teams. The studies demonstrate innovative and practical methods for improving hypertension control.

Cardiovascular diseases are approaching epidemic levels in Kenya and other low- and middle-income countries without accompanying effective preventive and therapeutic strategies. This is happening in the background of residual and emerging infections and other diseases of poverty, and increasing physical injuries from traffic accidents and noncommunicable diseases. Investments to create a skilled workforce and health care infrastructure are needed. Improving diagnostic capacity, access to high-quality medications, health care, appropriate legislation, and proper coordination are key components to ensuring the reversal of the epidemic and a healthy citizenry. Strong partnerships with the developed countries also crucial.

OBJECTIVES: The current study examined the role of emotional distress in explaining racial/ethnic differences in unhealthy sleep duration. DESIGN: Data from the 2004-2013 National Health Interview Survey were analyzed using SPSS 20. SETTING: Data were collected through personal household interviews in the United States. PARTICIPANTS: Of the total 261,686 participants (age>/=18 years), 17.0% were black, 83.0% were white, and the mean age was 48 years (SE=0.04). MEASUREMENTS: To ascertain total sleep duration, participants were asked, "How many hours of sleep do you get on average in a 24-hour period?" Sleep duration was coded as short sleep (<7hours), average sleep (7-8hours), or long sleep (>8hours). Emotional distress-feeling sad, nervous, restless, hopeless, worthless, and burdened over a 30-day period-was measured using Kessler-6, a 6-item screening scale. RESULTS: Of the participants reporting significant emotional distress (4.0% black, 3.5% white), chi2 analyses revealed that a higher percentage of blacks, compared with whites, reported unhealthy sleep durations. Relative to Whites, Blacks had increased prevalence of short sleep (prevalence ratio=1.32, P<.001) or long sleep (odds ratio =1.189, P<.001). The interaction between race/ethnicity and emotional distress was significantly associated with short (prevalence ratio=0.99, P<.001) and long sleep (odds ratio=0.98, P<.001) durations. CONCLUSIONS: Individuals of the black race/ethnicity or those reporting greater levels of emotional distress are more likely to report short or long sleep duration. Emotional distress might partially explain racial/ethnic differences in unhealthy sleep duration between blacks and whites.

BACKGROUND:Cardiac autonomic perturbations frequently antecede onset of paroxysmal atrial fibrillation (AF). Interventions that influence autonomic inputs to myocardium may prevent AF. However, whether low heart rate or heart rate variability (HRV), which are noninvasive measures of cardiac autonomic dysfunction, are associated with AF incidence is unclear. OBJECTIVES/OBJECTIVE:This study sought to study the association between HRV and risk of AF. METHODS:This study included 11,715 middle-aged adults in the ARIC (Atherosclerosis Risk In Communities) cohort with heart rate and HRV measures obtained from 2-min electrocardiogram recordings performed at baseline (1987 to 1989). These measures included SD of normal-to-normal RR intervals, high-frequency (HF) (0.15 to 0.40 Hz), low-frequency (0.04 to 0.15 Hz), and the low-frequency/HF ratio (denoting a greater sympathetic to parasympathetic dominance). Incident AF cases were ascertained by electrocardiogram at ARIC follow-up visits, hospital discharge diagnosis, or death certificates through 2011. RESULTS:During an average follow-up of 19.4 years, 1,580 or 13.5% of participants developed AF. A baseline heart rate <60 beats/min was associated modestly with an increased risk of AF. Lower overall HRV as well as increased sympathetic/parasympathetic tone were associated independently with a higher risk of AF; the hazard ratio for each 1 SD lower SD of normal-to-normal RR intervals was 1.14 (95% confidence interval: 1.08 to 1.21), for HF was 1.12 (95% confidence interval: 1.06 to 1.17), and for low frequency/HF was 1.08 (95% confidence interval: 1.03 to 1.14). CONCLUSIONS:Cardiac autonomic dysfunction denoted by low resting short-term HRV was associated with higher AF incidence. A low heart rate may be associated with higher AF risk. Further studies are needed to determine whether interventions in the general population to restore autonomic balance may prevent AF.

BACKGROUND:Evidence regarding the association of lower extremity peripheral arterial disease with quality of life (QOL) is mainly from selected clinical populations or relatively small clinical cohorts. Thus, we investigated this association in community-derived populations. METHODS AND RESULTS:Using data of 5115 participants aged 66 to 90 years from visit 5 (2011-2013) of the Atherosclerosis Risk in Communities Study, we quantified the associations of ankle-brachial index (ABI) with several QOL parameters, including 12-item Short-Form Health Survey (SF-12), after accounting for potential confounders using linear and logistic regression models. Peripheral arterial disease defined by an ABI <0.90 (n=402), was independently associated with a low SF-12 Physical Component Summary score (-3.26 [95% CI -5.60 to -0.92]), compared to the ABI reference 1.10 to 1.19 (n=1900) but not with the Mental Component Summary score (-0.07 [-2.21 to 2.06]). A low ABI was significantly associated with poorer status of all SF-12 physical domains (physical functioning, role-physical, bodily pain, and general health) but only vitality out of 4 mental domains. Similarly, low ABI values were more consistently associated with other physically related QOL parameters (leisure-time exercise/activity/walking) than mentally related parameters (significant depressive symptoms and hopeless feeling). Lower physical QOL was observed even in individuals with borderline low ABI (0.90 to 0.99; n=426). CONCLUSIONS:Low ABI (even borderline) was independently associated with poor QOL, especially for physical components, in community-dwelling older adults. QOL is a critical element for older adults, and thus, further studies are warranted to assess whether peripheral arterial disease-specific management can improve QOL in older populations.

BACKGROUND:Although heart failure (HF) disproportionately affects older adults, little data exist regarding the prevalence of American College of Cardiology/American Heart Association HF stages among older individuals in the community. Additionally, the role of contemporary measures of longitudinal strain and diastolic dysfunction in defining HF stages is unclear. METHODS:HF stages were classified in 6118 participants in the Atherosclerosis Risk in Communities study (67-91 years of age) at the fifth study visit as follows: A (asymptomatic with HF risk factors but no cardiac structural or functional abnormalities), B (asymptomatic with structural abnormalities, defined as left ventricular hypertrophy, dilation or dysfunction, or significant valvular disease), C1 (clinical HF without prior hospitalization), and C2 (clinical HF with earlier hospitalization). RESULTS:Using the traditional definitions of HF stages, only 5% of examined participants were free of HF risk factors or structural heart disease (Stage 0), 52% were categorized as Stage A, 30% Stage B, 7% Stage C1, and 6% Stage C2. Worse HF stage was associated with a greater risk of incident HF hospitalization or death at a median follow-up of 608 days. Left ventricular (LV) ejection fraction was preserved in 77% and 65% in Stages C1 and C2, respectively. Incorporation of longitudinal strain and diastolic dysfunction into the Stage B definition reclassified 14% of the sample from Stage A to B and improved the net reclassification index (P=0.028) and integrated discrimination index (P=0.016). Abnormal LV structure, systolic function (based on LV ejection fraction and longitudinal strain), and diastolic function (based on e', E/e', and left atrial volume index) were each independently and additively associated with risk of incident HF hospitalization or death in Stage A and B participants. CONCLUSIONS:The majority of older adults in the community are at risk for HF (Stages A or B), appreciably more compared with previous reports in younger community-based samples. LV ejection fraction is robustly preserved in at least two-thirds of older adults with prevalent HF (Stage C), highlighting the burden of HF with preserved LV ejection fraction in the elderly. LV diastolic function and longitudinal strain provide incremental prognostic value beyond conventional measures of LV structure and LV ejection fraction in identifying persons at risk for HF hospitalization or death.

OBJECTIVE: This study introduces a rapid picture naming test, the Mobile Universal Lexicon Evaluation System (MULES), as a novel, vision-based performance measure for concussion screening. The MULES is a visual-verbal task that includes 54 original photographs of fruits, objects and animals. We piloted MULES in a cohort of volunteers to determine feasibility, ranges of picture naming responses, and the relation of MULES time scores to those of King-Devick (K-D), a rapid number naming test. METHODS: A convenience sample (n=20, age 34+/-10) underwent MULES and K-D (spiral bound, iPad versions). Administration order was randomized; MULES tests were audio-recorded to provide objective data on temporal variability and ranges of picture naming responses. RESULTS: Scores for the best of two trials for all tests were 40-50s; average times required to name each MULES picture (0.72+/-0.14s) was greater than those needed for each K-D number ((spiral: 0.33+/-0.05s, iPad: 0.36+/-0.06s, 120 numbers), p<0.0001, paired t-test). MULES scores showed the greatest degree of improvement between trials (9.4+/-4.8s, p<0.0001 for trials 1 vs. 2), compared to K-D (spiral 1.5+/-3.3s, iPad 1.8+/-3.4s). Shorter MULES times demonstrated moderate and significant correlations with shorter iPad but not spiral K-D times (r=0.49, p=0.03). CONCLUSION: The MULES test is a rapid picture naming task that may engage more extensive neural systems than more commonly used rapid number naming tasks. Rapid picture naming may require additional processing devoted to color perception, object identification, and categorization. Both tests rely on initiation and sequencing of saccadic eye movements.