John P Forman

Harvard Medical School, Boston, Massachusetts, United States

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Publications (93)619.8 Total impact

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    ABSTRACT: Increased systolic blood pressure variability between outpatient visits is associated with increased incidence of cardiovascular end points. However, few studies have examined the association of visit-to-visit variability in systolic blood pressure with clinically relevant kidney disease outcomes. We analyzed the association of systolic blood pressure visit-to-visit variability with renal and cardiovascular morbidity and mortality among individuals with diabetes and nephropathy.
    American journal of kidney diseases : the official journal of the National Kidney Foundation. 07/2014;
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    ABSTRACT: Objective To determine whether daytime sleepiness is independently associated with coronary heart disease (CHD) and stroke or whether the positive association is explained by short sleep duration, disturbed sleep, and circadian disruption, conditions that are associated with cardiometabolic risk factors for vascular events. Methods Longitudinal analyses of data from the Nurses’ Health Study II comprising 84,003 female registered nurses aged 37 to 54 at baseline in 2001 with follow-up until 2009. Multivariate Cox regression was used to explore the relationship between reported daytime sleepiness and the incidence of either CHD or stroke (n = 500 cases). Results Women who reported daytime sleepiness almost every day, compared with rarely/never, had an elevated adjusted risk for cardiovascular disease (CVD) (HR = 1.58, 95% CI 1.15-2.17). Controlling for sleep variables (sleep duration, snoring, shift work, and sleep adequacy) or potential metabolic biological mediators of disrupted sleep (diabetes, hypercholesterolemia, and hypertension) appreciably attenuated the relationship (HR = 1.17, 95% CI 0.84 – 1.65; and HR = 1.34, 95% CI 0.97 – 1.85, respectively). Controlling for both sleep variables and metabolic risk factors eliminated an independent association (HR = 1.09, 95% CI 0.77 – 1.53). A similar pattern was observed for CHD and stroke individually. Conclusions Daytime sleepiness was not an independent risk factor for CVD in this cohort of women, but rather, was associated with sleep characteristics and metabolic abnormalities that are risk factors for CVD
    Sleep Medicine 07/2014; · 3.49 Impact Factor
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    ABSTRACT: To evaluate the associations of dietary fiber after myocardial infarction (MI) and changes in dietary fiber intake from before to after MI with all cause and cardiovascular mortality. Prospective cohort study. Two large prospective cohort studies of US women and men with repeated dietary measurements: the Nurses' Health Study and the Health Professionals Follow-Up Study. 2258 women and 1840 men who were free of cardiovascular disease, stroke, or cancer at enrollment, survived a first MI during follow-up, were free of stroke at the time of initial onset of MI, and provided food frequency questionnaires pre-MI and at least one post-MI. Associations of dietary fiber post-MI and changes from before to after MI with all cause and cardiovascular mortality using Cox proportional hazards models, adjusting for drug use, medical history, and lifestyle factors. Higher post-MI fiber intake was significantly associated with lower all cause mortality (comparing extreme fifths, pooled hazard ratio 0.75, 95% confidence interval 0.58 to 0.97). Greater intake of cereal fiber was more strongly associated with all cause mortality (pooled hazard ratio 0.73, 0.58 to 0.91) than were other sources of dietary fiber. Increased fiber intake from before to after MI was significantly associated with lower all cause mortality (pooled hazard ratio 0.69, 0.55 to 0.87). In this prospective study of patients who survived MI, a greater intake of dietary fiber after MI, especially cereal fiber, was inversely associated with all cause mortality. In addition, increasing consumption of fiber from before to after MI was significantly associated with lower all cause and cardiovascular mortality.
    BMJ (online) 04/2014; 348:g2659. · 17.22 Impact Factor
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    ABSTRACT: Blood pressure normally declines during the night ('dipping'); a blunted nocturnal decline is an important cardiovascular risk factor. Marriage may be associated with lower ambulatory blood pressure, although this may be confounded by socio-economic and dietary factors. We examined the association of marital status with nocturnal dipping and night-time SBP amongst individuals on a controlled diet. We analysed 325 individuals enrolled in the Dietary Approaches to Stop Hypertension trial who had available 24-h SBP data and who ingested a control diet. Logistic and linear regression models were fit to estimate the association of marital status with nocturnal dipping and mean night-time SBP. Of the 325 individuals, 52.9% were men, the average age was 45.1 years and 48.9% reported being married. Compared with nonmarried individuals, those who were married had greater adjusted odds of dipping [odds ratio (OR) 2.26; 95% confidence interval (CI) 1.26-4.03; P = 0.01]. In adjusted models, being married was associated with lower night-time SBP (-2.4 mmHg; 95% CI -3.8 to -0.9 mmHg; P = 0.002), with the suggestion of a greater association in married men compared with married women (-3.1 vs. -1.7 mmHg); there was less difference for married nonblacks compared with married blacks (-2.7 and -2.4 mmHg, respectively). Being married is independently associated with a greater likelihood of nocturnal dipping and with lower night-time SBP among individuals participating in a controlled dietary intervention; the association was particularly strong in married men. Marital status is a variable that may be considered in future analyses of ambulatory blood pressure.
    Journal of Hypertension 02/2014; · 4.22 Impact Factor
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    ABSTRACT: Introduction Hydrochlorothiazide, an effective antihypertensive medication commonly prescribed to blacks, decreases urinary calcium excretion. Blacks have significantly higher rates of hypertension and lower levels of 25-hydroxyvitamin D. Thus, they are more likely to be exposed to vitamin D supplementation and thiazide diuretics. The risk for hypercalcemia among blacks using vitamin D and hydrochlorothiazide is undefined. Methods We assessed the frequency of hypercalcemia in HCTZ users in a post-hoc analysis of a randomized, double-blind, dose-finding trial of 328 blacks (median age, 51 years) assigned to either placebo, or 1000, 2000, or 4000 international units of cholecalciferol (vitamin D3) daily for 3 months during the winter (2007-2010). Results Of the 328 participants, 84 reported hydrochlorothiazide use and had serum calcium levels assessed. Additionally, a comparison convenience group of 44 enrolled participants who were not taking hydrochlorothiazide had serum calcium measurements at 3-months but not at baseline. At 3-months, hydrochlorothiazide participants had higher calcium levels (0.2 mg/dL, p<.001) than non-hydrochlorothiazide participants, but only one participant in the hydrochlorothiazide group had hypercalcemia. In contrast, none of the non-hydrochlorothiazide participants had hypercalcemia. In linear regression model adjusted for age, sex, 25-hydroxyvitamin D at 3-months, and other covariates, only hydrochlorothiazide use [Estimate (SE):0.05(0.01) p=0.01] predicted serum calcium at 3-months. Conclusion In summary, vitamin D3 supplementation up to 4000 IU in hydrochlorothiazide users is associated with a rise in serum calcium but a low frequency of hypercalcemia. These findings suggest that participants of this population can use HCTZ with up to 4000 IU of vitamin D3 daily and experience a low frequency of hypercalcemia.
    The American journal of medicine 01/2014; · 5.30 Impact Factor
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    ABSTRACT: The healthiest dietary pattern for myocardial infarction (MI) survivors is not known. Specific long-term benefits of a low-carbohydrate diet (LCD) are unknown, whether from animal or vegetable sources. There is a need to examine the associations between post-MI adherence to an LCD and all-cause and cardiovascular mortality.
    Journal of the American Heart Association. 01/2014; 3(5).
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    ABSTRACT: IMPORTANCE Information about diet after myocardial infarction (MI) and mortality is limited, despite the growing number of MI survivors in the United States. OBJECTIVE To examine the association of post-MI dietary quality and changes from pre- to post-MI with all-cause and cardiovascular mortality among MI survivors. DESIGN, SETTING, AND PARTICIPANTS We included 2258 women from the Nurses' Health Study and 1840 men from the Health Professionals Follow-up Study. Participants had survived an initial MI during the study follow-up period and completed the pre- and post-MI food frequency questionnaire. Diet quality was measured using Alternative Healthy Eating Index 2010 (AHEI2010), which consists of food and nutrients associated with the risk of chronic disease reported in the literature. We adjusted for medication use, medical history, and lifestyle risk factors using Cox proportional hazards regression models. MAIN OUTCOMES AND MEASURES All-cause and cardiovascular mortality. RESULTS During follow-up, we confirmed 682 all-cause deaths for women and 451 for men. The median survival time after the initial MI onset was 8.7 years for women and 9.0 years for men. When the results were pooled, the adjusted hazard ratio (HR) was 0.76 (95% CI, 0.60-0.96) for all-cause mortality and 0.73 (95% CI, 0.51-1.04) for cardiovascular mortality, comparing the extreme quintiles of post-MI AHEI2010. A greater increase in the AHEI2010 score from pre- to post-MI was significantly associated with lower all-cause mortality (pooled HR, 0.71; 95% CI, 0.56-0.91) and cardiovascular mortality (pooled HR, 0.60; 95% CI, 0.41- 0.86), comparing the extreme quintiles. The adjusted HRs associated with post-MI AHEI2010 were 0.73 (95% CI, 0.58-0.93) for all-cause mortality and 0.81 (95% CI, 0.64-1.04) for cardiovascular mortality when the alcohol component was excluded. CONCLUSIONS AND RELEVANCE Myocardial infarction survivors who consume a higher-quality diet, which has been associated with a lower risk of coronary heart disease in primary prevention, have lower subsequent all-cause mortality.
    JAMA Internal Medicine 09/2013; · 13.25 Impact Factor
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    ABSTRACT: Several biomarkers of metabolic acidosis, including lower plasma bicarbonate, have been associated with prevalent hypertension in cross-sectional studies. We sought to examine prospectively whether lower plasma bicarbonate is associated with incident hypertension. We conducted a prospective case-control study nested within the Nurses' Health Study II. Plasma bicarbonate was measured in 695 nonobese women without hypertension at time of blood draw who subsequently developed hypertension during 6 years of follow-up. Control subjects were matched to case subjects according to age, race, time and day of blood draw, and day of menstrual cycle. We used unconditional logistic regression to generate odds ratios (ORs) for development of hypertension by quintile of baseline plasma bicarbonate. After adjusting for matching factors, body mass index, family history of hypertension, plasma creatinine, and dietary and lifestyle factors, higher plasma bicarbonate was associated with lower odds of developing hypertension across quintiles (P for linear trend = 0.04). Those in the highest compared with the lowest quintile of plasma bicarbonate had 31% lower odds of developing hypertension (OR = 0.69; 95% confidence interval = 0.48-0.99). Further adjustment for diet-estimated net endogenous acid production, plasma insulin, 25-hydroxyvitamin D, and uric acid did not alter these findings. Our case-control study is consistent with a modest association between higher plasma bicarbonate and reduced odds of developing hypertension among nonobese women, although our findings are of borderline statistical significance. Further research is required to confirm this finding as part of a larger prospective cohort study and to elucidate the mechanism for this relation.
    American Journal of Hypertension 08/2013; · 3.67 Impact Factor
  • JAMA The Journal of the American Medical Association 08/2013; 310(5):537. · 29.98 Impact Factor
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    ABSTRACT: Exogenous melatonin ameliorates insulin resistance in animals, while among humans, polymorphisms in the melatonin receptor gene are associated with insulin resistance. We aimed to investigate the association of endogenous nocturnal melatonin secretion with insulin resistance in humans. We analyzed the association between endogenous nocturnal melatonin secretion, estimated by measuring the main melatonin metabolite, 6-sulfatoxymelatonin, from the first morning urinary void, and the prevalence of insulin resistance based on fasting blood samples collected in a cross-sectional study of 1,075 US women (1997-1999) without diabetes, hypertension, or malignancy. Urinary 6-sulfatoxymelatonin level was standardized to urinary creatinine level; insulin resistance was defined as an insulin sensitivity index value (using the McAuley formula) less than 7.85. Logistic regression models included adjustment for age, body mass index, smoking, physical activity, alcohol intake, dietary glycemic index, family history of diabetes mellitus, blood pressure, plasma total cholesterol, uric acid, and estimated glomerular filtration rate. Higher nocturnal melatonin secretion was inversely associated with insulin levels and insulin resistance. In fully adjusted models, the odds ratio for insulin resistance was 0.45 (95% confidence interval: 0.28, 0.74) among women in the highest quartile of urinary 6-sulfatoxymelatonin:creatinine ratio compared with women in the lowest quartile. Nocturnal melatonin secretion is independently and inversely associated with insulin resistance.
    American journal of epidemiology 06/2013; · 5.59 Impact Factor
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    ABSTRACT: BACKGROUND: Acute sleep restriction has been shown to increase blood pressure and sympathetic nervous system activity. METHODS: We investigated the relationships between sleep duration and hypertension among women whose sleep durations were self-reported in 1986 (n = 82,130) and 2000 (n = 71,658) in the Nurses' Health Study I (NHS-I) and in 2001 (n = 84,674) in the Nurses' Health Study II (NHS-II). RESULTS: After controlling for multiple risk factors in logistic regression models, the prevalence of hypertension was significantly higher among women in all 3 groups who slept ≤5 hours (odds ratio = 1.19, 95% confidence interval [CI] = 1.14-1.25) per night compared with 7 hours. In prospective analyses using Cox regression shorter sleep duration of ≤5 hours per night was significantly associated with a higher incidence of hypertension only in younger women (hazard ratio [HR] =1.20, 95% CI = 1.09-1.31 for those aged <50 years; HR = 1.11, 95% CI = 1.00-1.23 for those aged 50-59 years). In both prevalent and incident analyses, results were consistent with obesity acting as a partial mediator. Results were not consistent with diabetes or hypercholesterolemia acting as mediators or with shift work, snoring, menopause, or postmenopausal hormone therapy acting as effect modifiers. CONCLUSIONS: Sufficient sleep could represent a lifestyle practice worthy of investigation as an approach to reduce hypertension incidence and prevalence.
    American Journal of Hypertension 04/2013; · 3.67 Impact Factor
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    ABSTRACT: Loss-of-function mutations in the melatonin receptor are associated with insulin resistance and type 2 diabetes. Additionally, in a cross-sectional analysis of persons without diabetes, lower nocturnal melatonin secretion was associated with increased insulin resistance. To study the association between melatonin secretion and the risk of developing type 2 diabetes. Case-control study nested within the Nurses' Health Study cohort. Among participants without diabetes who provided urine and blood samples at baseline in 2000, we identified 370 women who developed type 2 diabetes from 2000-2012 and matched 370 controls using risk-set sampling. Associations between melatonin secretion at baseline and incidence of type 2 diabetes were evaluated with multivariable conditional logistic regression controlling for demographic characteristics, lifestyle habits, measures of sleep quality, and biomarkers of inflammation and endothelial dysfunction. The median urinary ratios of 6-sulfatoxymelatonin to creatinine were 28.2 ng/mg (5%-95% range, 5.5-84.2 ng/mg) among cases and 36.3 ng/mg (5%-95% range, 6.9-110.8 ng/mg) among controls. Women with lower ratios of 6-sulfatoxymelatonin to creatinine had increased risk of diabetes (multivariable odds ratio, 1.48 [95% CI, 1.11-1.98] per unit decrease in the estimated log ratio of 6-sulfatoxymelatonin to creatinine). Compared with women in the highest ratio category of 6-sulfatoxymelatonin to creatinine, those in the lowest category had a multivariable odds ratio of 2.17 (95% CI, 1.18-3.98) of developing type 2 diabetes. Women in the highest category of melatonin secretion had an estimated diabetes incidence rate of 4.27 cases/1000 person-years compared with 9.27 cases/1000 person-years in the lowest category. Lower melatonin secretion was independently associated with a higher risk of developing type 2 diabetes. Further research is warranted to assess if melatonin secretion is a modifiable risk factor for diabetes within the general population.
    JAMA The Journal of the American Medical Association 04/2013; 309(13):1388-96. · 29.98 Impact Factor
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    ABSTRACT: Blacks have significantly higher rates of hypertension than whites, and lower circulating levels of 25-hydroxyvitamin D. There are few data about the effect of vitamin D3 (cholecalciferol) supplementation on blood pressure in blacks. During 2 winters from 2008 to 2010, 283 blacks (median age, 51 years) were randomized into a 4-arm, double-blind trial for 3 months of placebo, 1000, 2000, or 4000 international units of cholecalciferol per day. At baseline, 3 months, and 6 months, systolic and diastolic pressure and 25-hydroxyvitamin D were measured. The 3-month follow-up was completed in 250 (88%) participants. The difference in systolic pressure between baseline and 3 months was +1.7 mm Hg for those receiving placebo, -0.66 mm Hg for 1000 U/d, -3.4 mm Hg for 2000 U/d, and -4.0 mm Hg for 4000 U/d of cholecalciferol (-1.4 mm Hg for each additional 1000 U/d of cholecalciferol; P=0.04). For each 1-ng/mL increase in plasma 25-hydroxyvitamin D, there was a significant 0.2-mm Hg reduction in systolic pressure (P=0.02). There was no effect of cholecalciferol supplementation on diastolic pressure (P=0.37). Within an unselected population of blacks, 3 months of oral vitamin D3 supplementation significantly, yet modestly, lowered systolic pressure. Future trials of vitamin D supplementation on blood pressure are needed to confirm these promising results, particularly among blacks, a population for whom vitamin D deficiency may play a more specific mechanistic role in the pathogenesis of hypertension.
    Hypertension 04/2013; 61(4):779-85. · 6.87 Impact Factor
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    ABSTRACT: BACKGROUND AND OBJECTIVES: Increased systolic BP visit-to-visit variability (SBV) may be associated with higher overall mortality and cardiovascular events. However, few studies have examined these associations in patients with CKD, and the relation of SBV with CKD progression and ESRD has not been shown. This study analyzed the association of SBV with overall mortality, cardiovascular mortality, cardiovascular events, and renal events among individuals enrolled in the African American Study of Kidney Disease (AASK) trial. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: This was a prospective observational study of 908 participants during the trial phase of the AASK study, with at least 1 year of BP measurements available and followed for 3-6.4 years. SBV was calculated as the SD of the systolic pressure from five visits occurring 3-12 months after randomization. The association of SBV with risk of overall mortality, cardiovascular mortality, a composite of fatal and nonfatal cardiovascular events, and a composite of renal events was assessed using proportional hazards regression and adjusting for multiple potential confounders. RESULTS: Greater SBV was associated with higher overall mortality. The adjusted hazard ratio (95% confidence interval) was 2.82 (1.14-6.95) comparing the highest with lowest tertile of SBV. A similar comparison revealed that greater SBV was also associated with cardiovascular mortality (adjusted hazard ratio, 4.91; 1.12-21.50). SBV was associated with both the cardiovascular renal composite endpoints in unadjusted but not adjusted analyses. CONCLUSIONS: In African Americans with CKD, SBV is strongly and independently associated with overall and cardiovascular mortality.
    Clinical Journal of the American Society of Nephrology 03/2013; · 5.07 Impact Factor
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    ABSTRACT: BACKGROUND The association of preawake (difference between pre- and postwaking blood pressure (BP)) and sleep-through surge (difference between sleeping nadir and postwaking BP) with cardiovascular events is unclear. Examination of factors associated with surge may provide novel insights. We examined the association of race, which associates with nocturnal dipping, and plasma renin activity (PRA) with preawake and sleep-through surge among individuals on a controlled diet.METHODS We performed a post hoc analysis of 323 subjects from the Dietary Approaches to Stop Hypertension trial who had available 24-hour BP data and who ingested a control diet during a 3-week run-in period. Linear regression models were fit to estimate the association of race and PRA with preawake and sleep-through surge.RESULTSOf the 323 individuals, 55% were black, 53% were men, and the average age was 45 years. After controlling for other factors, black race was associated with a 3.2mm Hg lower preawake and a 3.7mm Hg lower sleep-through surge compared with nonblacks. In nonblacks, higher PRA was associated with greater preawake surge only. There was no association of PRA with either preawake or sleep-through surge in blacks. Additional adjustment for dipping status resulted in attenuation of the race-surge associations.CONCLUSIONS Black race is associated with lower preawake and sleep-through surge compared with nonblacks, but the effect is partially attenuated by dipping status. Higher PRA appears to be associated with a higher preawake surge in nonblacks only. Further research should address if morning surge is definitively associated with clinical outcomes in racial subgroups, independent of dipping.
    American Journal of Hypertension 03/2013; · 3.67 Impact Factor
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    ABSTRACT: OBJECTIVES: To develop an electronic registry of patients with chronic kidney disease (CKD) treated in a nephrology practice in order to provide clinically meaningful measurement and population management to improve rates of blood pressure (BP) control. METHODS: We combined data from multiple electronic sources: the billing system, structured fields in the electronic health record (EHR), and free text physician notes using natural language processing (NLP). We also used point-of-care worksheets to capture clinical rationale. RESULTS: Nephrologist billing accurately identified patients with CKD. Using an algorithm that incorporated multiple BP readings increased the measured rate of control (130/80 mm Hg) from 37.1% to 42.3%. With the addition of NLP to capture BP readings from free text notes, the rate was 52.6%. Data from point-of-care worksheets indicated that in 52% of visits in which patients were identified as not having controlled BP, patients were actually at goal based on BP readings taken at home or on that day in the office. CONCLUSIONS: Building a method for clinically meaningful continuous performance measurement of BP control is possible, but will require data from multiple sources. Electronic measurement systems need to grow to be able to capture and process performance data from patients as well as in real-time from physicians.
    Journal of the American Medical Informatics Association 01/2013; · 3.57 Impact Factor
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    ABSTRACT: OBJECTIVE: The renin-angiotensin-aldosterone system (RAAS), vitamin D, and parathyroid hormone have all been implicated as regulators of adipocytokines and inflammation. We evaluated human interventional study protocols to investigate whether controlled modulations of these calcium- and sodium-regulatory hormones could influence adipocytokines and inflammation in obesity and diabetes. METHODS: Post-hoc analyses of two separate human protocols (Protocol 1, n=14; Protocol 2, n=24) conducted in a clinical research setting after rigorous control of diet, posture, medications, and diurnal rhythm, were performed. Protocol 1 evaluated obese hypertensives with vitamin D deficiency who received an infusion of angiotensin II (AngII) before and after 1month of vitamin D(3) therapy. Protocol 2 evaluated obese subjects with type 2 diabetes who also received AngII. Adipocytokines and inflammatory markers were measured before and after vitamin D(3) therapy, and also before and after infusions of AngII. RESULTS: Vitamin D(3) therapy significantly raised 25(OH)D and 1,25(OH)(2)D concentrations, and lowered parathyroid hormone, but had no effect on concentrations of adiponectin, resistin, leptin, IL-6, PAI-1, urinary TGFβ1, or HOMA-IR. AngII infusions, despite significant elevations in blood pressure and serum aldosterone, did not influence adipocytokine concentrations in either protocol. CONCLUSION: In contrast to prior studies conducted in healthy populations, or those that could not control major regulators of the RAAS or adipocytokines, we observed that robust modulations in calcium- and sodium-regulatory hormones did not influence adipocytokines or inflammation in obesity or diabetes. Adipose-tissue physiology in these conditions may alter the hormonal regulation of inflammatory parameters.
    Metabolism: clinical and experimental 11/2012; · 3.10 Impact Factor
  • John P Forman, Walter C Willett
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    ABSTRACT: Apart from the specific findings of this analysis, the authors encourage the use of what they call a nutrient-wide association study (NWAS), analogous to a genome-wide association study (GWAS), to investigate dietary determinants of health outcomes(1). Similar to the agnostic approach used in a GWAS, the features of their approach include: the inclusion of all available nutrient exposures; non-incorporation of prior knowledge; adjustment of statistical tests for multiple comparisons; division of the primary dataset into training and test subsets; and the use of a confirmatory dataset. The primary objectives are to analyze all possible nutrient-disease hypotheses and to avoid false positive conclusions.
    Circulation 10/2012; · 15.20 Impact Factor
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    ABSTRACT: Cross-sectional studies and animal experiments suggest that methylmercury exposure could increase the risk of hypertension. This relationship has not been evaluated in large prospective studies. Using data from previous nested case-control studies in 2 separate prospective cohorts, we measured toenail mercury, a valid biomarker of long-term methylmercury exposure, among 6045 US men and women free of hypertension at baseline. Geometric mean toenail mercury concentrations were 0.08 μg/g in the lowest quintile and 0.74 μg/g in the highest quintile, the latter corresponding with exposures ≈2.0-fold higher than the US Environmental Protection Agency reference dose. Participants were followed prospectively (mean±SD follow-up, 14.9±7.9 years) for a new self-report of physician-diagnosed hypertension (3540 cases), shown to be >95% sensitive and specific for diagnosing hypertension in these cohorts as compared with review of medical charts and direct blood pressure measurement, respectively. After adjustment for demographic, clinical, and lifestyle risk factors, the hazard ratio (95% CI) for incident hypertension in the highest versus lowest quintile of mercury exposure was 0.96 (0.84-1.09) in women, 0.82 (0.62-1.08) in men, and 0.94 (0.84-1.06) in both cohorts combined. Findings were similar when more extreme categories of mercury were compared (across deciles, with geometric mean levels in highest decile ≈2.9-fold higher than the reference dose) and in analyses stratified by fish or omega-3 consumption, selenium levels, body mass index, and age. These findings from 2 separate large prospective cohort studies do not support any clinically apparent adverse effects of methylmercury exposure on the risk of hypertension in men or women, including at levels ≤2.5-fold higher than the reference dose.
    Hypertension 08/2012; 60(3):645-52. · 6.87 Impact Factor
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    David M Charytan, John P Forman
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    ABSTRACT: Interactions between sodium intake, the renin-angiotensin system, and renal and cardiovascular outcomes are incompletely understood. The analysis by Lambers Heerspink et al. shows that angiotensin receptor blockade improves diabetic nephropathy and cardiovascular disease more when dietary sodium intake is low, and suggests possible harm when sodium intake is high. These findings highlight dietary salt as a modifiable cardiovascular and renal risk factor and emphasize the need for detailed mechanistic studies.
    Kidney International 08/2012; 82(3):257-9. · 8.52 Impact Factor

Publication Stats

2k Citations
619.80 Total Impact Points

Institutions

  • 2005–2014
    • Harvard Medical School
      • • Department of Medicine
      • • Division of Nutrition
      Boston, Massachusetts, United States
  • 2004–2014
    • Brigham and Women's Hospital
      • • Department of Medicine
      • • Division of Endocrinology, Diabetes and Hypertension
      • • Division of Renal Medicine
      Boston, Massachusetts, United States
  • 2013
    • Columbia University
      • Department of Psychiatry
      New York City, NY, United States
    • University of Massachusetts Medical School
      Worcester, Massachusetts, United States
    • Massachusetts Department of Public Health
      Boston, Massachusetts, United States
  • 2008–2013
    • Partners HealthCare
      Boston, Massachusetts, United States
  • 2012
    • University of Maryland, Baltimore
      • Division of Nephrology
      Baltimore, MD, United States
  • 2011
    • University of North Carolina at Chapel Hill
      • Department of Obstetrics and Gynecology
      Chapel Hill, NC, United States
    • University of East Anglia
      Norwich, England, United Kingdom
  • 2009
    • Massachusetts General Hospital
      • Department of Medicine
      Boston, Massachusetts, United States