Associations between long-term aircraft noise exposure, cardiovascular disease, and mortality in US cohorts of female nurses.

There is limited research examining aircraft noise and cardiovascular disease (CVD) risk. The objective of this study was to investigate associations of aircraft noise with CVD among two US cohorts, the Nurses' Health Study (NHS) and Nurses' Health Study II (NHSII). Methods: Between 1994 and 2014, we followed 57,306 NHS and 60,058 NHSII participants surrounding 90 airports. Aircraft noise was modeled above 44 A-weighted decibels (dB(A)) and linked to geocoded addresses. Based on exposure distributions, we dichotomized exposures at 50 dB(A) and tested sensitivity of this cut-point by analyzing aircraft noise as categories (<45, 45-49, 50-54, ≥55) and continuously. We fit cohort-specific Cox proportional hazards models to estimate relationships between time-varying day-night average sound level (DNL) and CVD incidence and CVD and all-cause mortality, adjusting for fixed and time-varying individual- and area-level covariates. Results were pooled using random effects meta-analysis. Results: Over 20 years of follow-up, there were 4529 CVD cases and 14,930 deaths. Approximately 7% (n = 317) of CVD cases were exposed to DNL ≥50 dB(A). In pooled analyses comparing ≥50 with <50 dB(A), the adjusted hazard ratio for CVD incidence was 1.00 (95% confidence interval: 0.89, 1.12). The corresponding adjusted hazard ratio for all-cause mortality was 1.02 (95% confidence interval: 0.96, 1.09). Patterns were similar for CVD mortality in NHS yet underpowered. Conclusions: Among participants in the NHS and NHSII prospective cohorts who generally experience low exposure to aircraft noise, we did not find adverse associations of aircraft noise with CVD incidence, CVD mortality, or all-cause mortality.

Sleep Restriction and Recurrent Circadian Disruption Differentially Affects Blood Pressure, Sodium Retention, and Aldosterone Secretion.

Prolonged exposure to chronic sleep restriction (CSR) and shiftwork are both associated with incident hypertension and cardiovascular disease. We hypothesized that the combination of CSR and shiftwork's rotating sleep schedule (causing recurrent circadian disruption, RCD) would increase blood pressure, renal sodium retention, potassium excretion, and aldosterone excretion. Seventeen healthy participants were studied during a 32-day inpatient protocol that included 20-h "days" with associated scheduled sleep/wake and eating behaviors. Participants were randomly assigned to restricted (1:3.3 sleep:wake, CSR group) or standard (1:2 sleep:wake, Control group) ratios of sleep:wake duration. Systolic blood pressure during circadian misalignment was ∼6% higher in CSR conditions. Renal sodium and potassium excretion showed robust circadian patterns; potassium excretion also displayed some influence of the scheduled behaviors (sleep/wake, fasting during sleep so made parallel fasting/feeding). In contrast, the timing of renal aldosterone excretion was affected predominately by scheduled behaviors. Per 20-h "day," total sodium excretion increased, and total potassium excretion decreased during RCD without a change in total aldosterone excretion. Lastly, a reduced total renal sodium excretion was found despite constant oral sodium consumption and total aldosterone excretion, suggesting a positive total body sodium balance independent of aldosterone excretion. These findings may provide mechanistic insight into the observed adverse cardiovascular and renal effects of shiftwork.

Long-term aircraft noise exposure and risk of hypertension in the Nurses' Health Studies.

BACKGROUND: Aircraft noise can affect populations living near airports. Chronic exposure to aircraft noise has been associated with cardiovascular disease, including hypertension. However, previous studies have been limited in their ability to characterize noise exposures over time and to adequately control for confounders. OBJECTIVES: The aim of this study was to examine the association between aircraft noise and incident hypertension in two cohorts of female nurses, using aircraft noise exposure estimates with high spatial resolution over a 20-year period. METHODS: We obtained contour maps of modeled aircraft noise levels over time for 90 U.S. airports and linked them with geocoded addresses of participants in the Nurses' Health Study (NHS) and Nurses' Health Study II (NHS II) to assign noise exposure for 1994-2014 and 1995-2013, respectively. We used time-varying Cox proportional hazards models to estimate hypertension risk associated with time-varying noise exposure (dichotomized at 45 and 55 dB(A)), adjusting for fixed and time-varying confounders. Results from both cohorts were pooled via random effects meta-analysis. RESULTS: In meta-analyses of parsimonious and fully-adjusted models with aircraft noise dichotomized at 45 dB(A), hazard ratios (HR) for hypertension incidence were 1.04 (95% CI: 1.00, 1.07) and 1.03 (95% CI: 0.99, 1.07), respectively. When dichotomized at 55 dB(A), HRs were 1.10 (95% CI: 1.01, 1.19) and 1.07 (95% CI: 0.98, 1.15), respectively. After conducting fully-adjusted sensitivity analyses limited to years in which particulate matter (PM) was obtained, we observed similar findings. In NHS, the PM-unadjusted HR was 1.01 (95% CI: 0.90, 1.14) and PM-adjusted HR was 1.01 (95% CI: 0.89, 1.14); in NHS II, the PM-unadjusted HR was 1.08 (95% CI: 0.96, 1.22) and the PM-adjusted HR was 1.08 (95% CI: 0.95, 1.21). Overall, in these cohorts, we found marginally suggestive evidence of a positive association between aircraft noise exposure and hypertension.

Effect of daily 2000 IU versus 800 IU vitamin D on blood pressure among adults age 60 years and older: a randomized clinical trial.

BACKGROUND: Observational studies report higher blood pressure (BP) among individuals with lower 25-hydroxyvitamin D concentration. Whether dosage of vitamin D supplementation has a differential effect on BP control remains unclear. OBJECTIVE: The study aimed to determine if daily vitamin D supplementation with 2000 IU is more effective than 800 IU for BP control among older adults. METHODS: This randomized, double-blind, ancillary trial of the Zurich Multiple Endpoint Vitamin D Trial in Knee Osteoarthritis enrolled adults aged ≥60 y who underwent elective surgery due to severe knee osteoarthritis. Participants were randomly assigned to receive high dose (2000 IU) or standard dose (800 IU) daily vitamin D3 for 24 mo. Outcomes included daytime and 24-h mean systolic BP. BP variability and serum 25-hydroxyvitamin D concentration were examined in a post hoc and observational analysis. RESULTS: Of the 273 participants randomly assigned, 250 participants completed a follow-up 24-h ambulatory BP monitoring (mean age: 70.4 ± 6.4 y; 47.2% men). The difference in daytime mean systolic BP reduction between the 2000 IU (n = 123) and 800 IU (n = 127) groups was not statistically significant (-2.75 mm Hg vs. -3.94 mm Hg; difference: 1.18 mm Hg; 95% CI: -0.68, 3.05; P = 0.21), consistent with 24-h mean systolic BP. However, systolic BP variability was significantly reduced with 2000 IU (average real variability: -0.37 mm Hg) compared to 800 IU vitamin D3 (0.11 mm Hg; difference: -0.48 mm Hg; 95% CI: -0.94, -0.01; P = 0.045). Independent of group allocation, maximal reductions in mean BP were observed at 28.7 ng/mL of achieved serum 25-hydroxyvitamin D concentrations. CONCLUSIONS: While daily 2000 IU and 800 IU vitamin D3 reduced mean systolic BP over 2 y to a small and similar extent, 2000 IU reduced mean systolic BP variability significantly more compared with 800 IU. However, without a placebo control group we cannot ascertain whether vitamin D supplementation effectively reduces BP.This trial was registered at www.clinicaltrials.gov as NCT00599807.

Postanesthesia ultrasound facilitates creation of more preferred accesses without affecting access survival.

OBJECTIVE: The results of preoperative ultrasound (pre-US) vein mapping for hemodialysis access creation can be affected by environmental and clinical factors, such as ambient temperature, acute illness, recent phlebotomy, and hypovolemia. These factors may inadvertently exclude otherwise viable veins as options for access creation. We hypothesized that repeating the ultrasound vein mapping immediately preoperatively after anesthesia administration (post-US) identifies additional veins not appreciated by pre-US, thereby altering the operative plan and producing more preferred accesses, particularly more forearm accesses. METHODS: We performed a retrospective cohort study of patients (N = 323) at one institution who underwent pre-US followed by creation of a permanent dialysis access (fistula or graft) between January 2008 and December 2013. By applying the Silva criteria to pre-US vein mapping reports, a preoperative surgical plan was established. There were 99 patients who underwent only pre-US (group I); an additional post-US was performed in 224 patients (group II). Using multivariable logistic regression, we tested the association of post-US (group II) with pre-US alone (group I) with a change in operative plan and placement of a more preferred access (ie, more distal and autogenous). We also analyzed access survival using multivariable Cox proportional hazards regression and determined maturation rates for accesses in groups I and II. RESULTS: In group II, there were more changes in operative plan after controlling for potential confounders (adjusted odds ratio, 1.96; 95% confidence interval, 1.18-3.25), and more preferred accesses were created (adjusted odds ratio, 1.82; 95% confidence interval, 1.01-3.27). In addition, more autogenous accesses were created in group II when initially only upper arm graft options had been identified (P = .01); overall, more forearm accesses were created in group II (P = .03). There was no significant difference in access maturation and patency in comparing accesses in group I and group II, despite creation of autogenous accesses in group II that are usually associated with higher rates of access failure. In fact, forearm radial-cephalic autogenous accesses created in group II had secondary patency rates of 91% at 2 years. CONCLUSIONS: Our study supports the hypothesis that the use of post-US in addition to pre-US leads to placement of more preferred accesses while maintaining maturation and patency rates. Ultrasound evaluation after anesthesia should be considered a step in the process of care for hemodialysis access creation to improve outcomes.

Association between sex hormones and ambulatory blood pressure.

INTRODUCTION: Higher levels of total testosterone and lower levels of sex hormone-binding globulin (SHBG) have been associated with increased blood pressure (BP) in women with an inverse association between total testosterone and BP among men. Fewer studies have examined associations with 24-h ambulatory blood pressure (ABP), blunted nocturnal BP decline or the role of dehydroepiandrosterone sulfate (DHEAS), a precursor to androgens. METHODS: Baseline blood samples were assayed for 229 normotensive men (≥50 years) and women (≥55 years) participating in the VITamin D and OmegA-3 TriaL. Standardized seated BP (SBP and DBP) and 24-h ABP were measured by trained technicians. Self-reported cardiovascular risk factors and sociodemographic variables were reported on baseline questionnaires. Sex stratified linear regression models adjusted for age, race/ethnicity, BMI, smoking and alcohol estimated the association between each sex hormone and measures of BP and 24-h ABP. Logistic regression used to estimate associations with blunted nocturnal decline (>10% reduction in SBP or DBP during sleeping hours). RESULTS: Total testosterone and SHBG demonstrated significant inverse correlations with SBP whereas DHEAS was not significantly associated with BP. Among men, in multivariable analyses, each 10% increase in DHEAS was associated with a 0.41 mmHg higher seated DBP (ß = 4.29, 95% CI 0.84-7.73) and each 10% increase in total testosterone and SHBG was associated with a 0.54 mmHg (ß = -5.65, 95% CI -10.45 to -0.84) and 0.60 mmHg (ß = -6.30, 95% CI -11.38 to -1.21) decrease in seated DBP, respectively. No significant associations were observed among women. CONCLUSION: Among men only, we observed statistically significant inverse cross-sectional associations between total testosterone and SHBG with seated DBP, and a significant positive association with DHEAS levels.

Association Between Endometriosis and Hypercholesterolemia or Hypertension.

An altered hormonal or chronic systemic inflammatory milieu characterizing endometriosis may result in a higher risk of hypercholesterolemia and hypertension. Conversely, elevated low-density lipoprotein in hypercholesterolemia and chronic systemic inflammation resulting from hypertension may increase the risk of endometriosis. We assessed the association of laparoscopically confirmed endometriosis with hypercholesterolemia and hypertension in a large prospective cohort study. In 1989, 116 430 registered female nurses aged 25 to 42 completed the baseline questionnaire and were followed for 20 years. Multivariable Cox proportional hazards models were applied. In 1989, there were 4244 women with laparoscopically confirmed endometriosis and 91 554 women without. After adjusting for demographic, anthropometric, family history, reproductive, dietary, and lifestyle risk factors prospectively, comparing women with laparoscopically confirmed endometriosis to women without, the relative risks were 1.25 (95% confidence interval, 1.21-1.30) for development of hypercholesterolemia and 1.14 (95% confidence interval, 1.09-1.18) for hypertension. Conversely, the relative risks of developing laparoscopically confirmed endometriosis were 1.22 (95% confidence interval, 1.15-1.31) comparing women with hypercholesterolemia to women without and 1.29 (95% confidence interval, 1.18-1.41) comparing women with hypertension to women without. The strength of associations of laparoscopically confirmed endometriosis with hypercholesterolemia or hypertension was strongest among women aged ≤40 and weakened as age increased (P values for interaction <0.001). We observed that ≈45% of the associations between endometriosis and hypercholesterolemia and hypertension could be accounted for by treatment factors after endometriosis diagnosis, including greater frequency of hysterectomy/oophorectomy and earlier age for this surgery. In this large cohort study, laparoscopically confirmed endometriosis was prospectively associated with increased risk of hypercholesterolemia and hypertension. Conversely, hypercholesterolemia and hypertension were prospectively associated with higher risk of laparoscopically confirmed endometriosis.

Effect of Vitamin D on Endothelial Function: A Randomized, Double-Blind, Placebo-Controlled Trial.

BACKGROUND: In nonhypertensive individuals, lower levels of 25-hydroxyvitamin D (25[OH]D) have been associated with an increased risk of hypertension, and vitamin D deficiency has been associated with endothelial dysfunction in such individuals. However, the effect of vitamin D supplementation on endothelial dysfunction in nonhypertensive individuals has not been examined in a rigorous fashion. METHODS: In this randomized, double-blind, placebo-controlled trial of nonhypertensive, nondiabetic overweight, or obese individuals with vitamin D deficiency (body mass index ≥25 and 25[OH]D ≤ 20 ng/ml), we assigned subjects to receive either ergocalciferol (50,000 units) or matching placebo, once a week for 8 weeks. Our primary outcome was endothelial-dependent vasodilation (EDV) measured by brachial artery ultrasound at baseline and 8 weeks postrandomization. RESULTS: By the end of the trial, 46 and 47 participants were allocated to receive ergocalciferol and placebo, respectively. Mean 25(OH)D levels increased from 14.9 to 30.3 in the vitamin D group and 14.4 to 17.4 in the placebo. EDV did not change significantly with either vitamin D repletion (from 6.3 ± 3.6% at baseline to 6.1 ± 4.6% at 8 weeks; P value = 0.78) or placebo (7.9 ± 4.7% to 6.8 ± 4.7%; P = 0.17). The treatment effect P value (comparing the 8-week change with ergocalciferol to the change with placebo) was 0.35. CONCLUSIONS: In this randomized, double-blind, placebo-controlled trial, there was no improvement in endothelial function (measured as EDV) after repletion of vitamin D in overweight/obese nonhypertensive individuals.

A nested case-control study of the association between melatonin secretion and incident myocardial infarction.

OBJECTIVES: Low nocturnal melatonin secretion is associated with cardiovascular risk factors, diabetes and hypertension, while individuals with prevalent cardiovascular disease have lower nocturnal melatonin levels. However, the prospective association of melatonin secretion with myocardial infarction (MI) has not been studied. We aimed to study the association between melatonin secretion and the risk of developing MI. METHODS: We performed a prospective nested case-control study of participants from the Nurses' Health Study cohorts I and II. A total of 209 incident cases of fatal and non-fatal MI were identified among women who provided first morning voided urine specimens at baseline and were matched to 209 controls. Nocturnal melatonin secretion was assessed using 6-sulfatoxymelatonin concentrations in morning urines normalised to the urines' creatinine concentration. Multivariable conditional logistic regression was used to analyse associations independent of important risk factors. RESULTS: Lower melatonin secretion was significantly associated with a higher risk of MI. After conditioning on matching variables, the OR for every one unit lower log-transformed sulfatoxymelatonin/creatinine ratio was 1.51 (95% CI 1.16 to 1.96). In multivariable models controlling for factors included in the American Heart Association Cardiovascular Risk Score plus circadian factors, every one unit lower in the ratio was associated with a significantly increased risk of MI (OR, 1.40; 95% CI 1.02 to 1.93). Women in the highest category had an estimated absolute risk of MI of 84 cases per 100 000 person-years compared with 197 cases per 100 000 person-years in the lowest category. The association was strongly modified by body mass index (BMI) (p value for interaction=0.02). CONCLUSIONS: Lower melatonin secretion was significantly associated with a greater risk of incident MI in women with increased BMI. Melatonin may be a novel and modifiable risk factor for MI among such women.

Diet-dependent acid load and type 2 diabetes: pooled results from three prospective cohort studies.

AIMS/HYPOTHESIS: Studies suggest a potential link between low-grade metabolic acidosis and type 2 diabetes. A western dietary pattern increases daily acid load but the association between diet-dependent acid load and type 2 diabetes is still unclear. This study aimed to assess whether diet-dependent acid load is associated with the risk of type 2 diabetes. METHODS: We examined the association between energy-adjusted net endogenous acid production (NEAP), potential renal acid load (PRAL) and animal protein-to-potassium ratio (A:P) on incident type 2 diabetes in 67,433 women from the Nurses' Health Study, 84,310 women from the Nurses' Health Study II and 35,743 men from the Health Professionals' Follow-up Study who were free from type 2 diabetes, cardiovascular disease and cancer at baseline. Study-specific HRs were estimated using Cox proportional hazards models with time-varying covariates and were pooled using a random effects meta-analysis. RESULTS: We documented 15,305 cases of type 2 diabetes during 4,025,131 person-years of follow-up. After adjustment for diabetes risk factors, dietary NEAP, PRAL and A:P were positively associated with type 2 diabetes (pooled HR [95% CI] for highest (Q5) vs lowest quintile (Q1): 1.29 [1.22, 1.37], p trend <0.0001; 1.29 [1.22, 1.36], p trend <0.0001 and 1.32 [1.24, 1.40], p trend <0.0001 for NEAP, PRAL and A:P, respectively). These results were not fully explained by other dietary factors including glycaemic load and dietary quality (HR [95% CI] for Q5 vs Q1: 1.21 [1.09, 1.33], p trend <0.0001; 1.19 [1.08, 1.30] and 1.26 [1.17, 1.36], p trend <0.0001 for NEAP, PRAL and A:P, respectively). CONCLUSIONS/INTERPRETATION: This study suggests that higher diet-dependent acid load is associated with an increased risk of type 2 diabetes. This association is not fully explained by diabetes risk factors and overall diet quality.

Recognition and Management of Resistant Hypertension.

Despite improvements in hypertension awareness and treatment, 30%-60% of hypertensive patients do not achieve BP targets and subsequently remain at risk for target organ damage. This therapeutic gap is particularly important to nephrologists, who frequently encounter treatment-resistant hypertension in patients with CKD. Data are limited on how best to treat patients with CKD and resistant hypertension, because patients with CKD have historically been excluded from hypertension treatment trials. First, we propose a consistent definition of resistant hypertension as BP levels confirmed by both in-office and out-of-office measurements that exceed appropriate targets while the patient is receiving treatment with at least three antihypertensive medications, including a diuretic, at dosages optimized to provide maximum benefit in the absence of intolerable side effects. Second, we recommend that each patient undergo a standardized, stepwise evaluation to assess adherence to dietary and lifestyle modifications and antihypertensive medications to identify and reduce barriers and discontinue use of substances that may exacerbate hypertension. Patients in whom there is high clinical suspicion should be evaluated for potential secondary causes of hypertension. Evidence-based management of resistant hypertension is discussed with special considerations of the differences in approach to patients with and without CKD, including the specific roles of diuretics and mineralocorticoid receptor antagonists and the current place of emerging therapies, such as renal denervation and baroreceptor stimulation. We endorse use of such a systematic approach to improve recognition and care for this vulnerable patient group that is at high risk for future kidney and cardiovascular events.

The effect of vitamin D on renin-angiotensin system activation and blood pressure: a randomized control trial.

OBJECTIVE: Disruption of vitamin D signaling in rodents causes activation of the rennin-angiotensin system (RAS) and development of hypertension. Observational studies in humans found lower circulating 25-hydroxyvitamin D [25(OH)D] is associated with increased RAS activity and blood pressure (BP). We performed the first randomized control trial to investigate the effects of vitamin D supplementation on the RAS in humans. METHODS: Vitamin D deficient, [25(OH)D ≤20 ng/ml), overweight individuals without hypertension were randomized into a double-blind, placebo-controlled trial of 8-weeks treatment with ergocalciferol or placebo. Kidney-specific RAS activity, measured using renal plasma flow response to captopril in high sodium balance, was assessed at baseline and 8 weeks, as was systemic RAS activity and 24-h ambulatory BP. RESULTS: In total, 84 participants completed the study. Mean 25[OH]D levels increased from 14.7 to 30.3 ng/ml in the ergocalciferol group, P value < 0.0001, and from 14.3 to 17.4 ng/ml in the placebo group, P value = 0.3. The renal plasma flow response to captopril was 33.9 ±â€Š56.1 ml/min per 1.73 m at baseline and 35.7 ±â€Š47.7 ml/min per 1.73 m at 8 weeks in the ergocalciferol group (P value = 0.83); and was 37.3 ±â€Š46.9 ml/min per 1.73 m at baseline and 35.9 ±â€Š26.2 ml/min per 1.73 m at 8 weeks in the placebo group (P value = 0.78). Ergocalciferol had no effect on PRA, AngII, or 24-h BP measurements. CONCLUSIONS: This trial found no benefit from correcting vitamin D deficiency on RAS activity or BP after 8 weeks. These findings are not consistent with the hypothesis that vitamin D is a modifiable target for lowering BP in vitamin D deficient individuals.

Effect of Uric Acid-Lowering Agents on Endothelial Function: A Randomized, Double-Blind, Placebo-Controlled Trial.

Higher levels of serum uric acid are independently associated with endothelial dysfunction, a mechanism for incident hypertension. Overweight/obese individuals are more prone to endothelial dysfunction than their lean counterparts. However, the effect of lowering serum uric acid on endothelial dysfunction in these individuals has not been examined thoroughly. In this randomized, double-blind, placebo-controlled trial of nonhypertensive, overweight, or obese individuals with higher serum uric acid (body mass index ≥25 kg/m2 and serum uric acid ≥5.0 mg/dL), we assigned subjects to probenecid (500-1000 mg/d), allopurinol (300-600 mg/d), or matching placebo. The primary outcome was endothelium-dependent vasodilation measured by brachial artery ultrasound at baseline and 8 weeks. By the end of the trial, 47, 49, and 53 participants had been allocated to receive probenecid, allopurinol, and placebo, respectively. Mean serum uric acid levels significantly decreased in the probenecid (from 6.1 to 3.5 mg/dL) and allopurinol groups (from 6.1 to 2.9 mg/dL) but not in the placebo group (6.1 to 5.6 mg/dL). None of the interventions produced any significant change in endothelium-dependent vasodilation (probenecid, 7.4±5.1% at baseline and 8.3±5.1% at 8 weeks; allopurinol, 7.6±6.0% at baseline and 6.2±4.8% at 8 weeks; and placebo, 6.5±3.8% at baseline and 7.1±4.9% at 8 weeks). In this randomized, double-blind, placebo-controlled trial, uric acid lowering did not affect endothelial function in overweight or obese nonhypertensive individuals. These data do not support the hypothesis that uric acid is causally related to endothelial dysfunction, a potential mechanism for development of hypertension.

Potato intake and incidence of hypertension: results from three prospective US cohort studies.

OBJECTIVE: To determine whether higher intake of baked or boiled potatoes, French fries, or potato chips is associated with incidence of hypertension. DESIGN: Prospective longitudinal cohort studies. SETTING: Healthcare providers in the United States. PARTICIPANTS: 62 175 women in Nurses' Health Study, 88 475 women in Nurses' Health Study II, and 36 803 men in Health Professionals Follow-up Study who were non-hypertensive at baseline. MAIN OUTCOME MEASURE: Incident cases of hypertension (self reported diagnosis by healthcare provider). RESULTS: Compared with consumption of less than one serving a month, the random effects pooled hazard ratios for four or more servings a week were 1.11 (95% confidence interval 0.96 to 1.28; P for trend=0.05) for baked, boiled, or mashed potatoes, 1.17 (1.07 to 1.27; P for trend=0.001) for French fries, and 0.97 (0.87 to 1.08; P for trend=0.98) for potato chips. In substitution analyses, replacing one serving a day of baked, boiled, or mashed potatoes with one serving a day of non-starchy vegetables was associated with decreased risk of hypertension (hazard ratio 0.93, 0.89 to 0.96). CONCLUSION: Higher intake of baked, boiled, or mashed potatoes and French fries was independently and prospectively associated with an increased risk of developing hypertension in three large cohorts of adult men and women.

Association of short sleep duration and rapid decline in renal function.

The kidney is influenced by circadian rhythms and is entrained to the sleep-wake cycle allowing anticipation of the metabolic and physiological demands of the kidney throughout a 24-hour cycle. Although sleep disruption has been studied extensively in cardiovascular and metabolic disease, its association with chronic kidney disease has not been shown. We examined this in a prospective cohort study of 4238 participants from the Nurses' Health Study and analyzed the association of self-reported sleep duration with decline in renal function over an 11-year period (1989 to 2000). Individuals who reported shorter sleep duration were more likely to experience a rapid decline in estimated glomerular filtration rate (30% or more). Compared with sleeping 7 to 8 hours per night, the adjusted odds ratios for a rapid decline in renal function were a significant 1.79 (95% CI, 1.06-3.03) for 5 hours or less sleep per night, a significant 1.31 (95% CI, 1.01-1.71) for 6 hours sleep per night, but an insignificant 0.88 (95% CI, 0.50-1.57) for 9 or more hours sleep per night. Similarly, there was a significant trend in the adjusted annualized decline in estimated glomerular filtration rate of 1.2 ml/min/1.73 m(2)/year, 0.9 ml/min/1.73 m(2)/year, 0.8 ml/min/1.73 m(2)/year, and 0.8 ml/min/1.73 m(2)/year for individuals sleeping 5 hours or less per night, 6 hours per night, 7 to 8 hours per night, and 9 hours or more per night, respectively. Thus, shorter sleep duration is prospectively and independently associated with faster decline in renal function.

Long-Term Exposure to Particulate Matter and Self-Reported Hypertension: A Prospective Analysis in the Nurses' Health Study.

BACKGROUND: Studies have suggested associations between elevated blood pressure and short-term air pollution exposures, but the evidence is mixed regarding long-term exposures on incidence of hypertension. OBJECTIVES: We examined the association of hypertension incidence with long-term residential exposures to ambient particulate matter (PM) and residential distance to roadway. METHODS: We estimated 24-month and cumulative average exposures to PM10, PM2.5, and PM2.5-10 and residential distance to road for women participating in the prospective nationwide Nurses' Health Study. Hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated for incident hypertension from 1988 to 2008 using Cox proportional hazards models adjusted for potential confounders. We considered effect modification by age, diet, diabetes, obesity, region, and latitude. RESULTS: Among 74,880 participants, 36,812 incident cases of hypertension were observed during 960,041 person-years. In multivariable models, 10-µg/m3 increases in 24-month average PM10, PM2.5, and PM2.5-10 were associated with small increases in the incidence of hypertension (HR: 1.02, 95% CI: 1.00, 1.04; HR: 1.04, 95% CI: 1.00, 1.07; and HR: 1.03, 95% CI: 1.00, 1.07, respectively). Associations were stronger among women < 65 years of age (HR: 1.04, 95% CI: 1.01, 1.06; HR: 1.07, 95% CI: 1.02, 1.12; and HR: 1.05, 95% CI: 1.01, 1.09, respectively) and the obese (HR: 1.07, 95% CI: 1.04, 1.12; HR: 1.15, 95% CI: 1.07, 1.23; and HR: 1.13, 95% CI: 1.07, 1.19, respectively), with p-values for interaction < 0.05 for all models except age and PM2.5-10. There was no association with roadway proximity. CONCLUSIONS: Long-term exposure to particulate matter was associated with small increases in risk of incident hypertension, particularly among younger women and the obese. CITATION: Zhang Z, Laden F, Forman JP, Hart JE. 2016. Long-term exposure to particulate matter and self-reported hypertension: a prospective analysis in the Nurses' Health Study. Environ Health Perspect 124:1414-1420; http://dx.doi.org/10.1289/EHP163.

Healthful Dietary Patterns and the Risk of Hypertension Among Women With a History of Gestational Diabetes Mellitus: A Prospective Cohort Study.

Women who developed gestational diabetes mellitus represent a high-risk population for hypertension later in life. The role of diet in the progression of hypertension among this susceptible population is unknown. We conducted a prospective cohort study of 3818 women with a history of gestational diabetes mellitus in the Nurses' Health Study II as part of the ongoing Diabetes & Women's Health Study. These women were followed-up from 1989 to 2011. Incident hypertension was identified through self-administered questionnaires that were validated previously by medical record review. Adherence scores for the alternative Healthy Eating Index 2010, the alternative Mediterranean diet, and the Dietary Approaches to Stop Hypertension were computed for each participant. Cox proportional hazard models were used to evaluate the associations between dietary scores and hypertension while adjusting for major risk factors for hypertension. We documented 1069 incident hypertension cases during a median of 18.5 years of follow-up. After adjustment for major risk factors for hypertension, including body mass index, alternative Healthy Eating Index 2010, alternative Mediterranean diet, and Dietary Approaches to Stop Hypertension scores were significantly inversely associated with the risk of hypertension; hazard ratio and 95% confidence interval comparing the extreme quartiles (highest versus lowest) were 0.76 (0.61-0.94; P for linear trend =0.03) for AHEI score, 0.72 (0.58-0.90; P for trend =0.01) for Dietary Approach to Stop Hypertension score, and 0.70 (0.56-0.88; P for trend =0.002) for alternative Mediterranean diet score. Adherence to a healthful dietary pattern was related to a lower subsequent risk of developing hypertension among women with a history of gestational diabetes mellitus.

Hypertension, use of antihypertensive medications, and risk of epithelial ovarian cancer.

Few studies have examined the associations of hypertension and antihypertensive medications with ovarian cancer. In particular, beta-blockers, one of the most commonly prescribed medications to treat hypertension, may reduce ovarian cancer risk by inhibiting beta-adrenergic signaling. We prospectively followed 90,384 women in the Nurses' Health Study (NHS) between 1988-2012 and 113,121 NHSII participants between 1989-2011. Hypertension and use of antihypertensive medications were self-reported biennially. Cox proportional hazards models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs). We documented 948 ovarian cancer cases during follow-up. Similar results were observed in the two cohorts. While hypertension was not associated with ovarian cancer risk (Pooled HR = 1.01; 95% CI = 0.88, 1.16), current use of any antihypertensive medication was associated with slightly increased risk compared to never users (Pooled HR = 1.18; 95% CI: 1.02, 1.37). This increased risk was primarily due to use of thiazide diuretics (Pooled HR = 1.37; 95% CI: 1.13, 1.68). No associations were observed for beta-blockers or angiotensin-converting-enzyme inhibitors. Calcium channel blockers (CCBs) were associated with suggestively reduced risk (NHS HR = 0.73; 95% CI: 0.53, 1.01), after adjusting for all antihypertensive medications. Associations were similar among hypertensive women and stronger for longer use of thiazide diuretics and CCBs. In conclusion, our results provided no evidence that beta-blockers were associated with reduced ovarian cancer risk. In contrast, we observed an increased risk for use of thiazide diuretics that should be confirmed in other studies.

Fruit and Vegetable Consumption and the Incidence of Hypertension in Three Prospective Cohort Studies.

Increased fruit and vegetable intake lowers blood pressure in short-term interventional studies. However, data on the association of long-term intake of fruits and vegetables with hypertension risk are scarce. We prospectively examined the independent association of whole fruit (excluding juices) and vegetable intake, as well as the change in consumption of whole fruits and vegetables, with incident hypertension in 3 large longitudinal cohort studies: Nurses' Health Study (n=62 175), Nurses' Health Study II (n=88 475), and Health Professionals Follow-up Study (n=36 803). We calculated hazard ratios and 95% confidence intervals for fruit and vegetable consumption while controlling for hypertension risk factors. Compared with participants whose consumption was ≤4 servings/week, the pooled hazard ratios among those whose intake was ≥4 servings/day were 0.92(0.87-0.97) for total whole fruit intake and 0.95(0.86-1.04) for total vegetable intake. Similarly, compared with participants who did not increase their fruit or vegetable consumption, the pooled hazard ratios for those whose intake increased by ≥7 servings/week were 0.94(0.90-0.97) for total whole fruit intake and 0.98(0.94-1.01) for total vegetable. Analyses of individual fruits and vegetables yielded different results. Consumption levels of ≥4 servings/week (as opposed to <1 serving/month) of broccoli, carrots, tofu or soybeans, raisins, and apples was associated with lower hypertension risk. In conclusion, our results suggest that greater long-term intake and increased consumption of whole fruits may reduce the risk of developing hypertension.