The Association of Subscapular Skinfold with All-Cause, Cardiovascular and Cerebrovascular Mortality

Purpose

Previous studies suggested inconsistent relationship between subscapular skinfold and all-cause, cardiovascular, and cerebrovascular mortality. Therefore, the present study aimed to investigate the associations between subscapular skinfold with all-cause, cardiovascular, and cerebrovascular mortality.

Patients and Methods

Data were collected from the National Health and Nutrition Examination Survey (NHANES, 1999–2006) with follow-up data through 31 December 2015. Participants were categorized by subscapular skinfold quartiles. The hazard ratios (HRs) and 95% confidence intervals (CIs) were evaluated using the multivariate Cox regression model and subgroup analysis. Kaplan–Meier curves were used to present cause-specific mortalities and used Cox cubic regression splines to examine the association of subscapular skinfold with cause-specific mortalities.

Results

A total of 16,402 subjects (49.61% male) were involved in our study. After a mean follow-up of 141.73 months, there were 3078 (18.77%), 392 (2.39%), and 128 (0.78%) cases of all-cause, cardiovascular, and cerebrovascular mortality, respectively. Participants in the highest quartile of subscapular skinfold (≥24.80mm) versus the lowest (<13.20mm) had lower risk for all-cause mortality (HR, 0.71; 95% CI, 0.57–0.89; P for trend = 0.007) and cardiovascular mortality (HR, 0.44; 95% CI, 0.23–0.83; P for trend = 0.023) in the fully adjusted model. In the age-stratified analysis, subscapular skinfold was only inversely associated with all-cause and cardiovascular disease mortality in people ≥65 years of age (all P-interaction <0.001). No significant difference was found between subscapular skinfold and cerebrovascular mortality (all P > 0.05).

Conclusion

Subscapular skinfold showed an inverse association with all-cause and cardiovascular disease mortality in people aged ≥65 years.

Association of systolic blood pressure with atrial fibrillation among treated hypertensive patients

BACKGROUND

Although many studies have suggested the association between elevated blood pressure and atrial fibrillation (AF), how the relationship between systolic blood pressure (SBP) and AF differ by antihypertensive treatment has been unclear. Therefore, this study aimed to explore the relationship between SBP and AF in hypertensive patients with or without antihypertensive treatment.

METHODS

This was a cross-sectional study that enrolled 7,808 hypertensive patients aged ≥18 years old in 2013 in Guangdong, China. AF was screened and diagnosed by rest 12-lead electrocardiogram (ECG) or by self-reported. Patients were categorized into 5 groups according to a 10 mmHg increment in SBP. We then performed logistic regression and restricted cubic spline regression to evaluate the relationship between SBP and AF.

RESULTS

Out of 7,808 participants (women 52.9%, mean age 62.3 years), 78 cases of AF were identified. Both univariate and multivariate logistic regression illustrated that SBP associated with a lower chance of AF in all participants when SBP was treated as a continuous variable (P<0.05) or as a categorical variable (P for trend <0.001). Similar trend was found in patients with antihypertensive therapy (P for trend <0.001) but not for those without antihypertensive medications.

CONCLUSIONS

Our findings suggested that higher SBP is associated with lower likelihood of AF among all hypertensive patients and participants with antihypertensive treatment.

Dietary Manganese, Plasma Markers of Inflammation, and the Development of Type 2 Diabetes in Postmenopausal Women: Findings From the Women's Health Initiative

OBJECTIVE

To examine the association between manganese intake and the risk of type 2 diabetes in postmenopausal women and determine whether this association is mediated by circulating markers of inflammation.

RESEARCH DESIGN AND METHODS

We included 84,285 postmenopausal women without a history of diabetes from the national Women's Health Initiative Observational Study (WHI-OS). Replication analysis was then conducted among 62,338 women who participated in the WHI-Clinical Trial (WHI-CT). Additionally, data from a case-control study of 3,749 women nested in the WHI-OS with information on biomarkers of inflammation and endothelial dysfunction were examined using mediation analysis to determine the relative contributions of these known biomarkers by which manganese affects type 2 diabetes risk.

RESULTS

Compared with the lowest quintile of energy-adjusted dietary manganese, WHI-OS participants in the highest quintile had a 30% lower risk of type 2 diabetes (hazard ratio [HR] 0.70 [95% CI 0.65, 0.76]). A consistent association was also confirmed in the WHI-CT (HR 0.79 [95% CI 0.73, 0.85]). In the nested case-control study, higher energy-adjusted dietary manganese was associated with lower circulating levels of inflammatory biomarkers that significantly mediated the association between dietary manganese and type 2 diabetes risk. Specifically, 19% and 12% of type 2 diabetes risk due to manganese were mediated through interleukin 6 and hs-CRP, respectively.

CONCLUSIONS

Higher intake of manganese was directly associated with a lower type 2 diabetes risk independent of known risk factors. This association may be partially mediated by inflammatory biomarkers.

Association of mean arterial pressure with all-cause and cardiovascular mortality in young adults

BACKGROUND

Mean arterial pressure (MAP) is a predictor of all-cause and cardiovascular disease (CVD) mortality in middle-aged population and elderly, but less evidence has been shown in young adults.

OBJECTIVES

We examined the associations of MAP with all-cause and CVD mortality in young adults aged between 18 and 40 years.

METHODS

Data were from the National Health and Nutrition Examination Survey (1999-2006) and participants were followed up to 31 December 2015. MAP was categorised by quartiles. Multivariable Cox proportional hazards models and Kaplan-Meier survival curves were performed to estimate the association between MAP, all-cause and CVD mortality.

RESULTS

There were a total of 8356 (4598 women (55.03%)) participants with the mean age of 26.63±7.01 years, of which 265 (3.17%) and 10 (0.12%) cases of all-cause and cardiovascular mortality occurred during a median follow-up duration of 152.96±30.45 months, respectively. There was no significant difference in the survival rate by MAP quartiles (p=0.058). When MAP was treated as a continuous variable, the multivariable adjusted HRs for all-cause and CVD mortality were 1.00 (95% CI 0.96 to 1.04; p=0.910) and 0.94 (95% CI 0.77 to 1.14; p=0.529), respectively. When using the lowest quartile (Q1) as referent, the adjusted HRs for all-cause mortality from Q2 to Q4 were 1.16 (95% CI 0.56 to 2.42), 1.06 (95% CI 0.48 to 2.32) and 0.91 (95% CI 0.37 to 2.24; p for tend was 0.749) after adjusting for potential confounders.

CONCLUSION

There was no significant association of MAP with all-cause and CVD mortality in young adults with a relatively short follow-up time.

Effects of waist to height ratio, waist circumference, body mass index on the risk of chronic diseases, all-cause, cardiovascular and cancer mortality

BACKGROUND

Given the fat redistribution in later stages of life, how the associations between abdominal obesity and the risk of morbidity and mortality have changed with age have not been elucidated, especially for waist to height ratio (WHtR).

OBJECTIVE

To compare the strength of association between obesity indices and chronic diseases at baseline, and the subsequent mortality risk among US adults.

METHODS

We included 21 109 participants from National Health and Nutrition Examination Survey 1999-2014. We performed logistic regression and receiver operating curve analysis to examine the discriminatory power of obesity indicators on cardiometabolic diseases and cancer at baseline. Sex-stratified and age-stratified Cox models were constructed to explore the prospective association between obesity indices and all-cause, cardiovascular and cancer mortality.

RESULTS

Elevated WHtR, elevated waist circumference (WC) and body mass index (BMI)-classified obesity are associated with higher odds of hypertension (OR: 1.37-2.13), dyslipidemia (OR: 1.06 to 1.75, all p<0.05) and diabetes (OR: 1.40-3.16, all p<0.05). WHtR had significantly better discriminatory power to predict cardiometabolic health than BMI, especially for diabetes (area under the curve: 0.709 vs 0.654). After multivariable adjustment, all obesity indicators are associated with lower risk of all-cause mortality among females aged ≥65 years (HR: 0.64 to 0.85), but the association was only significant for BMI when obesity indicators were mutually adjusted (HR: 0.79).

CONCLUSIONS

WHtR and WC appeared to be the better indicators for cardiometabolic health than BMI. However, BMI had a stronger and inverse association with a greater risk of all-cause mortality among older females.

The association between serum uric acid levels and ischemic stroke in essential hypertension patients

Objectives: The association between serum uric acid (SUA) and ischemic stroke is still inconsistent across population. This study aimed to examine the association between SUA and ischemic stroke in essential hypertension patients. Methods: This retrospective study recruited participants from September 2011 to December 2012, in the Liao-bu community, Guangdong Province, China, and followed them until 31 December 2016. Participants were divided into quartiles based on SUA concentrations. Hazard ratio (HR) and confidence intervals (CIs) was estimated from Cox proportional hazards models, and propensity score analysis, Kaplan-Meier survival curves and receiver operating characteristic (ROC) curve were performed to evaluate the relationship between SUA and the risk of ischemic stroke. Results: A total of 5473 eligible hypertensive subjects were enrolled in this study, 2666 (48.71%) of them were males with an average age of 62.02 ± 13.76 years. A total of 155 (2.83%) ischemic stroke occurred after the mean follow-up period of 4.5 years. After adjusting for potential confounders, comparing with the lowest quartiles of SUA, multivariable HR (95%CI) for ischemic stroke for participants with SUA at the second, third and fourth quartiles were 1.13 (95%CI: 1.10, 1.81), 1.39 (95%CI: 1.18, 1.89), and 1.64 (95%CI: 1.19, 1.95), respectively (P < 0.0001 for trend). Elevated SUA was positively associated with ischemic stroke (HR = 1.41, 95%CI: 1.16, 1.84; P < 0.01) and the propensity scores analysis (HR = 1.45, 95%CI: 1.17, 1.90; P < 0.01) showed the similar results. Gender subgroup analysis showed SUA was an independent risk of ischemic stroke in female (HR = 1.35, 95%CI: 1.11, 1.81, P = 0.002) and male (HR = 1.53, 95%CI: 1.14, 1.92, P < 0.001). ROC curve demonstrated that SUA yielded an AUC of 0.7476 (95%CI: 0.7098, 0.7855, P < 0.001) for predictive of ischemic stroke. Conclusions: SUA was an independent risk factor for ischemic stroke, and also have a good predictive value ischemic stroke among hypertensive patients in Chinese community.

Association between pulse pressure and ischaemic stroke in elderly patients with hypertension

BACKGROUND

The association between pulse pressure (PP) and the risk of first ischaemic stroke (IS) is inconsistent. Therefore, we evaluated the association between PP and the risk of first IS among elderly hypertensive population in China.

METHODS

This was a retrospective cohort study. Patients with hypertension and aged ≥60 years were recruited. Multivariate Cox regression was performed to evaluate the association between PP and the risk of IS. We further stratified the regression models into subgroups and test for interaction to assess whether the associations were modified by other covariates.

RESULTS

A total of 3315 patients with hypertension (44.49% male; mean age 71.41±7.20 years) were included, and 206 cases of IS occurred with a median follow-up of 5.5 years. The results showed that per SD mm Hg increment in PP was associated with a 17% (95% CI 1.05 to 1.40, p=0.0172) increased risk of IS. Moreover, the HR of IS for the highest quartile of PP was 1.46 (95% CI 1.18 to 1.73, p=0.0011, p for trend <0.001) comparing with the lowest quartile of PP. Subgroup analysis showed that population aged ≥70 years, male, patients with smoking or drinking habit, diabetes at baseline, being overweight, with uncontrolled blood pressure or did not take antihypertensive drugs have a higher risk for IS.

CONCLUSIONS

We found that PP was significantly associated with IS and was an independent risk factor for IS.

Environmental heavy metals and cardiovascular diseases: Status and future direction

Cardiovascular disease (CVD) and environmental degradation are leading global health problems of our time. Recent studies have linked exposure to heavy metals to the risks of CVD and diabetes, particularly in populations from low- and middle-income countries, where concomitant rapid development occurs. In this review, we 1) assessed the totality, quantity, and consistency of the available epidemiological studies, linking heavy metal exposures to the risk of CVD (including stroke and coronary heart disease); 2) discussed the potential biological mechanisms underlying some tantalizing observations in humans; and 3) identified gaps in our knowledge base that must be investigated in future work. An accumulating body of evidence from both experimental and observational studies implicates exposure to heavy metals, in a dose-response manner, in the increased risk of CVD. The limitations of most existing studies include insufficient statistical power, lack of comprehensive assessment of exposure, and cross-sectional design. Given the widespread exposure to heavy metals, an urgent need has emerged to investigate these putative associations of environmental exposures, either independently or jointly, with incident CVD outcomes prospectively in well-characterized cohorts of diverse populations, and to determine potential strategies to prevent and control the impacts of heavy metal exposure on the cardiometabolic health outcomes of individuals and populations.

The relationship between mean telomere length and blood pressure: results from the National Health and Nutrition Examination Surveys

Background

Recent studies have shown that telomere length has significantly relationship with different age-related diseases. However, the relationship between mean telomere length (MTL) and elevated blood pressure (BP) has been unclear. Therefore, the aim of the recent study was tried to explore the association of MLT with BP.

Methods

There were 5,981 subjects from the National Health and Nutrition Examination Surveys (NHANES, 1999–2002) was included in analysis. The MTL was measured using the quantitative polymerase chain reaction (PCR) method and expressed in telomere-to-single copy gene (T/S) ratio and grouped into quartiles. Multivariate linear [expressed in beta and 95% confidence interval (CI)], logistic regression [odds ratios (ORs) and 95% CI] analyses and smooth curve fitting were performed to evaluate the relationship between MTL, BPs and the likelihood of hypertension.

Results

The mean age of the participants was 45.2±17.3 years, including 2,923 (48.9%) males. After adjusting for potential confounders, MLT was significantly related to the prevalence of hypertension (OR: 0.12, 95% CI: 0.02, 0.94; P=0.04). Smooth curve fitting found a non-linear relationship between MTL, the levels of systolic and diastolic blood pressure (SBP/DBP) and the prevalence of hypertension. The inflection points for the smooth curve of MLT were at 0.86, 1.02 and 0.80 (T/S ratio) respectively. The betas (95% CIs) for SBP [–12.58 (–20.07, –5.09), P<0.01 and 2.25 (0.07, 4.43), P=0.04] and DBP [4.88 (1.29, 8.47), P<0.01 and –3.30 (–5.54, –1.06), P<0.01], and ORs (95% CIs) for the prevalence of hypertension [0.02 (0.001, 9.71), P=0.15 and 0.26 (0.026, 2.60), P=0.25] on the left and right of the inflection point, respectively.

Conclusions

Our findings revealed that MTL was related with SBP, DBP and the odds of hypertension in a non-linear manner.

Relationship between body mass index and ischaemic stroke in Chinese elderly hypertensive patients

BACKGROUND

Despite obesity being a major risk factor for ischaemic stroke (IS), the association between body mass index (BMI) and IS in patients with hypertension remains uncertain.

OBJECTIVE

To assess the association between BMI and IS among elderly hypertensive patients in China.

METHODS AND RESULTS

We recruited 3500 hypertensive patients aged ≥60 between 1 January 2010 and 31 December 2011 in China and ascertained their stroke status until December 2016. Multivariate Cox regression was used to evaluate the association between BMI and IS with interaction tests for exposure and covariates. A total of 3315 subjects (mean age 71.41±7.20 years, 44.5% were men) were included for data analysis. During an average follow-up period of 5.5 years, there were 206 onset cases (6.21%) of IS. When BMI was treated as a continuous variable, it was positively associated with the incidence of new onset IS (HR=1.14; 95% CI: 1.05 to 1.34; p=0.005) after adjusting for potential confounders. Meanwhile, when BMI was treated as a categorical variable, the highest category (≥28 kg/m²) was strongly associated with an increased risk for IS compared with normal BMI category (18.5 to 24 kg/m²) (HR=1.36, 95% CI: 1.09 to 1.80; p<0.001) in the fully adjusted model. Subgroup and interaction analysis also demonstrated that BMI independently associated with IS among males, smokers, alcohol drinkers, diabetic patients, people with uncontrolled blood pressure, decreased estimated glomerular filtration rate and those aged ≥70 years.

CONCLUSION

BMI was significantly associated with IS and was an independent risk of IS in Chinese elderly hypertensive patients.

Prehypertension and risk for all-cause and cardiovascular mortality by diabetes status: results from the national health and nutrition examination surveys

Background

It is unclear whether prehypertension alone or combined with diabetes associate with a higher risk for cardiovascular or all-cause mortality. The purpose of this study was to explore the relationship between prehypertension and all-cause and cardiovascular mortality stratified by diabetes status.

Methods

All participants aged ≥18 years were enrolled from the 1999–2014 National Health and Nutrition Examination Surveys (NHANES). Prehypertension was defined as systolic/diastolic blood pressure (BP): 120–139/80–89 mmHg. The status of cardiovascular and all-cause mortality of participants were followed up through 31 December 2015. We performed Cox proportional hazards models and Kaplan-Meier survival curves to evaluate the relationships as mentioned above.

Results

In general, we enrolled 26,070 participants while 15,295 (58.67%) of them did not have diabetes nor prehypertension, 8,870 (34.02%) had prehypertension alone, 835 (3.20%) had diabetes alone, and 1,070 (4.11%) had both diabetes and prehypertension. Compared with participants without diabetes nor prehypertension, the multivariable adjusted hazard ratios and 95% confidence interval (CI) for all-cause mortality among participants with prehypertension alone, diabetes alone, and both diabetes and prehypertension were 1.08 (95% CI: 0.95, 1.23), 1.26 (0.98, 1.62), and 1.67 (1.38, 2.03) (P for trend <0.001), for cardiovascular mortality, the corresponding hazard ratios and 95% CI were 1.40 (95% CI: 0.92, 2.14), 2.21 (1.12, 4.38), and 2.87 (1.65, 4.99) (P for trend <0.001) respectively.

Conclusions

Our findings suggested that prehypertension associated with an increased risk for cardiovascular and all-cause mortality when compared with diabetes, but not for prehypertension alone. Early screening and intervention for BP among diabetic patients may be beneficial.

Association of circulating selenium concentration with dyslipidemia: Results from the NHANES

BACKGROUND

Observational studies have suggested that selenium levels might associate with the risk of cardio-metabolic diseases, but how circulating selenium is related to dyslipidemia remains inconclusive.

OBJECTIVES

To investigate the association of circulating selenium levels with lipid profiles and dyslipidemia among US adults.

METHODS

Using the data collected from the National Health and Nutrition Examination Survey (NHANES 1999-2006), we performed multivariate logistic regression to examine the association of circulating selenium levels (in quartiles) with total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), non-HDL-C, and atherogenic index (AI).

RESULTS

We included 2903 adults (49.3 % male) (average age: 61.9) for analysis. Circulating selenium had non-linear association with TC, LDL-C, HDL-C, and AI (all p < 0.05). When comparing with the lowest quartile, subjects with the highest quartile of circulating selenium (>147.00 μg/L) had the higher odds of elevated TG (OR: 1.75, 95% CI = 1.14, 2.68), TC (OR: 2.47, 95% CI = 1.62, 3.76), LDL-C (OR: 2.52, 95% CI = 1.60, 3.96), non-HDL-C (OR: 2.17, 95% CI = 1.41, 3.33), AI (OR: 1.20, 95% CI = 0.73, 1.97) and low-HDL-C (OR: 2.10, 95% CI = 1.19, 3.72). Similar patterns were observed in subgroup analysis.

CONCLUSIONS

Higher circulating selenium levels had non-linear association with lipid profiles and the increased odds of dyslipidemia.

A U-shaped association between serum uric acid with all-cause mortality in normal-weight population

BACKGROUND

It is uncertain how serum uric acid (SUA) associated with all-cause mortality among people with normal weight, hence was explored in this study.

METHODS

We enrolled participants from 1999 to 2006 National Health and Nutrition Examination Survey (NHANES) that had mortality status through 31 December 2015. We estimated adjusted hazard ratios (HRs) and 95% confidence intervals (CI) for all-cause mortality using Cox proportional hazard models, and propensity score analyses were performed. We also performed restricted cubic splines to demonstrate the nonlinear relationship, and used subgroup analysis to examine the effect modification.

RESULTS

We enrolled 6169 participants (2905 men and 3264 women, mean age 42.3 ± 21.4 years) and 1060 (17.2%) cases of all-cause mortality occurred during the mean follow-up of 11.9 years. When using the lowest quartile of SUA as referent, the multivariable HRs for all-cause mortality increased in not parallel with the quartiles of SUA (HRs were 0.92 (95%CI: 0.68, 1.23), 1.10 (95%CI: 0.82, 1.47), and 1.08 (95%CI: 0.80, 1.45) from the second to the fourth quartiles, respectively. When treating SUA as continuous variable, the HRs for all-cause mortality were 1.07 (95%CI: 1.00, 1.15; P = 0.046), 1.03 (95%CI: 0.94, 1.12; P = 0.518) and 1.15 (95%CI: 1.01, 1.31; P = 0.032) in all population, male and female subjects, respectively. Elevated SUA was associated with all-cause mortality and the propensity scores analysis showed the similar results. Subgroup analysis showed SUA was an independent risk of all-cause mortality in female (HR1.17, 95%CI: 1.05, 1.31, P = 0.005), people aged <60 years (HR1.18, 95%CI: 1.03, 1.35, P = 0.018), non-diabetic population (HR1.10, 95%CI: 1.02, 1.18, P = 0.017) and people with eGFR<90 (HR1.10, 95%CI: 1.02, 1.19, P = 0.016). Smoothing spline plots suggested the optimal SUA for the lowest risk of all-cause mortality was approximately 4.7 mg/dl.

CONCLUSION

In normal-weight population, SUA was seemed to be a U-shaped relationship with all-cause mortality.

Relationship between serum uric acid level and all-cause and cardiovascular mortality in population with obesity

BACKGROUND

We aimed to investigate the association between serum uric acid (SUA) and all-cause or cardiovascular mortality among participants with obesity.

METHOD

All participants were included from the 1999 to 2014 National Health and Nutrition Examination Survey with follow-up mortality assessment through 31 December 2015. Cox proportional hazards models were built to estimate adjusted HRs and 95% CIs for mortality according to baseline uric acid in quartiles. Obesity was defined as body mass index ≥30 (kg/m²). Generalised additive model (GAM) and two-piecewise linear regression models were performed to explore any non-linearity in associations.

RESULTS

There were 12 637 adults with obesity eligible for analysis. There were 999 (7.91%) all-cause and 147 (1.16%) cardiovascular mortality occurred during the mean follow-up of 98.11 months. Comparing with the lowest quartile of SUA, the highest SUA group did not have significant association with all-cause (HR 1.08, 95% CI 0.76 to 1.52) and cardiovascular mortality (HR 1.63, 95% CI 0.58 to 4.53) after adjusting for various confounding factors. GAM and two-piecewise linear regression model demonstrated a non-linearly relationship between SUA and all-cause mortality, and the corresponding cut-off point was 6.5 mg/dL. However, there is no significant relationship between uric acid and cardiovascular death on both sides of the cut-off value of 6.1 mg/dL.

CONCLUSIONS

SUA showed a J-shaped relationship with all-cause mortality, but no significant with cardiovascular mortality in adults with obesity.

Gender difference in the association of serum selenium with all-cause and cardiovascular mortality

Objectives: The relationship between selenium and all-cause mortality has been inconsistent from observational studies and clinical trials. The present study aimed to reveal the relationship between serum selenium and all-cause and cardiovascular disease (CVD) mortality and the potential gender differences.Methods: All participants were recruited from the 1999-2006 National Health and Nutrition Examination Survey (NHANES). Participants with available serum selenium data were followed up until 31 December 2015. Cox proportional hazards models were performed to estimate adjusted hazard ratios (HRs) and 95% confidence intervals (CI) for all-cause and CVD mortality according to baseline selenium level in quartiles. Multivariable-adjusted spline curves were performed to detect non-linearity in relationships.Results: There were 2,903 subjects (50.7% female) included in this study. The mean age was 61.9 ± 13.7 years, and the mean selenium levels were 136.4 ± 19.6 ug/L. A total of 858 (29.6%) cases of all-cause mortality and 126 (4.3%) CVD mortality occurred during the median follow-up duration of 10.2 years. On average, deceased participants had lower serum selenium levels, (135.1 ± 22.3 vs. 137.0 ± 18.4 ug/L; P = 0.02). Serum selenium was also lower in female than male (134.7 ± 19.7 vs. 138.2 ± 19.4 ug/L; P < 0.01). Comparing with the lowest quartile, participants with the highest selenium concentration had a lower risk for all-cause (HR: 0.60, 95%CI: 0.45, 0.78; P < 0.01, P for trend<0.01) and CVD mortality (HR: 0.73, 95%CI: 0.37, 1.43; P = 0.36, P for trend = 0.90). Selenium was significantly associated with all-cause and CVD mortality among both males and females, but only associated with CVD mortality in among females.Conclusion: This study demonstrated significant relationship between serum selenium and all-cause mortality in both genders, but the relationship with CVD mortality was only significant in females.

Serum Vitamin D, Sleep Pattern and Cardiometabolic Diseases: Findings from the National Health and Nutrition Examination Survey

OBJECTIVE

Although poor sleep health and vitamin D deficiency may be associated with diabetes and hypertension, whether this association shows a trend depending on vitamin D concentration is unclear.

SUBJECTS AND METHODS

We analyzed data from 10,742 participants (4997 men) from the 2007-2014 National Health and Nutrition Examination Survey. Abnormal sleep pattern (ie, short sleep duration, sleep complaint, and/or sleep disorder), lifestyle factors, serum vitamin D level, and the status of diabetes and hypertension were assessed. Logistic regression was performed to estimate the odds ratio (OR) and 95% confidence interval (CI).

RESULTS

Serum vitamin D significantly interacted with short sleep duration and abnormal sleep pattern (both p = 0.003) on the association with diabetes in men. Short sleep duration (OR: 1.82, 95% CI = 1.29, 2.57) and abnormal sleep pattern (OR: 1.95, 95% CI = 1.38, 2.77) were associated with diabetes in men with serum vitamin D of >75 nmol/L. Serum vitamin D significantly interacted with sleep complaint on the association with hypertension in men and women (both p < 0.05). The magnitude of association between sleep complaint and hypertension in men was stronger when serum vitamin D level was <50 nmol/L (OR: 2.26, 95% CI = 1.57, 3.25) than when the level was >75 nmol/L (OR: 1.28, 95% CI = 0.90, 1.83). Similarly, the magnitude of association between sleep complaint and hypertension in women was stronger when serum vitamin D level was <50 nmol/L (OR: 2.09, 95% CI = 1.53, 2.86) than when the level was >75 nmol/L (OR: 1.64, 95% CI = 0.98, 2.72). No significant interactions were observed between serum vitamin D level and other sleep variables.

CONCLUSION

Abnormal sleep pattern is associated with a high risk of diabetes and hypertension. The relationship between sleep complaint and hypertension may be strong in people with vitamin D deficiency, and this observation should be verified by prospective studies.

Impacts of Pre-Diabetes or Prehypertension on Subsequent Occurrence of Cardiovascular and All-Cause Mortality among Population without Cardiovascular Diseases

BACKGROUND

Among the population without cardiovascular diseases (CVD), it is unclear whether pre-diabetes and/or prehypertension elevated the risk of all-cause and cardiovascular mortality.

METHODS

All participants without CVD at baseline were recruited from the 1999-2014 National Health and Nutrition Examination Survey (NHANES), with survival status being updated until 31 December 2015. Cox proportional hazards models and subgroup analyses were performed to estimate hazard ratios (HRs) and 95% confidence interval (CI).

RESULTS

There were 23,622 participants (11,233 [47.6%] male) with mean age of 37.2 years. Compared to participants without prehypertension or pre-diabetes, the HRs for all-cause mortality among participants with prehypertension alone, pre-diabetes alone, and combined pre-diabetes and prehypertension were 1.04 (95% CI: 0.88, 1.24), 0.96 (95% CI:0.76, 1.21), and 1.19 (95% CI:0.98, 1.46), respectively. The corresponding HRs for cardiovascular mortality were 1.51 (95% CI: 0.83, 2.77), 1.40 (95% CI: 0.64, 3.06), and 1.70 (95% CI: 0.88, 3.27), respectively. A subgroup analysis showed that participants with combined pre-diabetes and prehypertension had a higher risk of all-cause mortality among younger participants, higher BMI, white population, and people with elevated non-HDLC. Moreover, the association between combined pre-diabetes and prehypertension and cardiovascular death was only significant among people with elevated non-HDLC.

CONCLUSION

Pre-diabetes combined with prehypertension might elevate the risk of all-cause mortality among subjects, particularly for those with elevated body weight, high non-HDLC, younger participants or white population.

Systolic Blood Pressure, Cardiovascular Mortality, and All-Cause Mortality in Normoglycemia, Prediabetes, and Diabetes

BACKGROUND

The optimal blood pressure (BP) level for diabetic patients remains controversial, while studies provided limited evidence on BP management for individuals with normoglycemia or prediabetes. We aimed to investigate the associations between systolic blood pressure (SBP) and all-cause and cardiovascular (CVD) mortality among US adults with different glycemic profiles.

METHODS

We used data from the 1999-2014 National Health and Nutrition Examination Survey (NHANES, n=40,046) with comprehensive baseline examination and follow-up assessment. Restricted cubic spline analysis was performed to examine dose-response relationship between SBP and mortality risk. Cox regression models were used to estimate hazard ratios of all-cause mortality and CVD mortality for SBP categories.

RESULTS

U-shaped associations between SBP and all-cause mortality were observed regardless of glucose status. The relationship between SBP and CVD mortality was found to be U-shaped only in normoglycemic participants. The lowest mortality risk of optimal SBP (mmHg) by group was 115-120 (normoglycemia), 120-130 (prediabetes), and 125-135 (diabetes). When compared with the reference group, SBP < 100 mmHg was significantly associated with 49% (HR=1.49, 95% CI: 1.13-1.96), 57% (1.57, 1.07-2.3), and 59% (1.59, 1.12-2.25) higher all-cause mortality risk in people with normoglycemia, prediabetes, and diabetes, respectively. The multivariable-adjusted HRs of all-cause mortality for SBP ≥150 mmHg were 1.51 (1.25-1.82), 1.56 (1.27-1.93), and 1.33 (1.08-1.64), respectively. As for CVD mortality, the multivariable-adjusted HRs were 2.85 (1.29-6.33) for SBP <100 mmHg and 2.71 (1.56-4.69) for SBP ≥150 mmHg in normoglycemia; HR was 1.66 (1.05-2.63) for SBP ≥150 mmHg in diabetic patients.

CONCLUSION

U-shaped relationships between SBP and all-cause mortality were observed regardless of diabetes status. The optimal SBP range was gradually higher with worsening glucose status.

Relationship between diastolic blood pressure and the first ischaemic stroke in elderly patients with hypertension

BACKGROUND

It is uncertain how diastolic blood pressure (DBP) may associate with ischaemic stroke in elder patients with hypertension. We aimed to explore this relationship in a Chinese community.

METHODS

A total of 3315 participants aged ≥60 years with essential hypertension were enrolled between January 2010 and December 2011, and being followed up until 31 December 2016. DBP levels were categorised into five groups (<60, 60-70, 70-80, 80-90 and ≥90 mm Hg), using 70-80 mm Hg as referent. We performed Cox regression analysis and subgroup analyses to evaluate the relationship between DBP and the incidence of ischaemic stroke.

RESULTS

Among the 3315 participants, 44.49% were men and they were 71.4 years old on average. During a median follow-up period of 5.5 years, there were 206 onset cases of ischaemic stroke. The HRs for the first ischaemic stroke in the fully adjusted model were 1.32 (95% CI 0.73 to 2.40) for DBP <70 mm Hg, 1.50 (95% CI 1.13 to 2.73) for DBP between 80 and 89.9 mm Hg and 2.31 (95% CI 1.14 to 4.68) for DBP ≥90 mm Hg compared with DBP between 70 and 79.9 mm Hg (p=0.020 for trend). Subgroup and interaction analysis showed no significant findings.

CONCLUSIONS

DBP had a non-linear association with the risk of ischaemic stroke among Chinese elderly patients with hypertension. DBP between 70 and 80 mm Hg may be an appropriate indicator for a lower stroke risk.

Association of pulse pressure with all-cause mortality in young adults

Background

Pulse blood pressure was significantly associated with all-cause mortality in middle-aged and elderly populations, but less evidence was known in young adults.

Objective

To assess the association of pulse pressure (PP) with all-cause mortality in young adults.

Methods

This cohort from the 1999–2006 National Health and Nutrition Examination Survey included adults aged 18–40 years. All included participants were followed up until the date of death or 31 December 2015. PP was categorised into three groups: <50, 50~60, ≥60 mm Hg. Cox proportional hazards models and subgroup analysis were performed to estimate the adjusted HRs and 95% CIs for all-cause mortality.

Results

After applying the exclusion criteria, 8356 participants (median age 26.63±7.01 years, 4598 women (55.03%)) were included, of which 265 (3.17%) have died during a median follow-up duration of 152.96±30.45 months. When treating PP as a continuous variable, multivariate Cox analysis showed that PP was an independent risk factor for all-cause mortality (HR 1.94, 95% CI 1.02 to 3.69; p=0.0422). When using PP<50 mm Hg as referent, from the 50~60 mm Hg to the ≥60 mm Hg group, the risks of all-cause mortality for participants with PP ranging 50–60 mm Hg or ≥60 mm Hg were 0.93 (95% CI 0.42 to 2.04) and 1.15 (95% CI 0.32 to 4.07) (P for tend was 0.959). Subgroup analysis showed that PP (HR 2.00, 95% CI 1.05 to 3.82; p=0.0360) was associated with all-cause mortality among non-hypertensive participants.

Conclusion

Among young adults, higher PP was significantly associated with an increased risk of all-cause mortality, particularly among those without hypertension.

Changes in dietary habits and prevalence of cardiovascular risk factors among school students in Macao, China

OBJECTIVE

Given the increasing burden of childhood obesity, it is important to examine the changes in dietary habits and prevalence of cardiovascular risk factors among Macao students.

METHODS

A cross-sectional study was conducted among primary and secondary school students in Macao, China in 2014-2015 with addition to data collected from 2008 to 2009 for comparison. The dietary behaviours, prevalence of obesity and dyslipidaemia were compared by study period.

SUBJECTS

In 2014-2015, dietary assessment was conducted among 3635 students, physical assessment was conducted among 1427 school students. In 2008-2009, dietary assessment was conducted among 4271 students, physical assessment was conducted among 1700 school students.

RESULTS

When compared with students in 2008, higher percentage of students from present study period consumed dairy products, crispy food and chocolate, while fewer students had fruits, vegetables and fried food at least once every day. Despite lower prevalence of elevated total cholesterol and low-density-lipoprotein cholesterol, the rate of general obesity, low high-density-lipoprotein cholesterol and hyperglycaemia has increased significantly in 2014-2015. Students aged 12-14 consumed less fruits and vegetables and suffered from higher rate of general and abdominal obesity, as well as low high-density-lipoprotein cholesterol and elevated serum triglycerides in 2014-15.

CONCLUSIONS

The students' diet had both favourable and unfavourable changes. The rate of obesity and dyslipidaemia rises, while the situation for students aged 12-14 is more concerning.

Reporting sample size calculations for randomized controlled trials published in nursing journals: A cross-sectional study

BACKGROUND

Prior sample size calculation is essential to ensure that a randomized controlled trial (RCT) has enough power to detect any statistical differences between two groups while not over-recruiting participants. However, the compliance among RCTs published in nursing field is unknown.

OBJECTIVE

To describe the reporting of sample size methodology and parameters used in RCTs published in nursing journals.

DESIGN

A cross-sectional database search of all RCTs published in nursing journals was conducted.

SETTING

116 journals in the category of nursing.

PARTICIPANTS

Not applicable.

METHODS

A database search was conducted to identify all RCTs published in nursing journals from January 2016 to December 2016. Two-arm RCTs were reviewed to see if sample size estimation was mentioned in the text and if the parameters were sufficient for the estimation. For RCTs with effect size, sample sizes were recomputed and compared with the reported size.

RESULTS

Two hundred and twenty-three RCTs were included in this study, and 143 (64.1%) studies mentioned how they obtained their sample sizes. Among these 143 studies, 132 (92.3%), 133 (93.0%), 33 (23.1%), and 84 (58.7%) specified their levels of significance (α), powers, tails of the test, and effect size related information, respectively. Only 22 (15.4%) provided all the necessary parameters to compute their sample sizes. Out of the 84 RCTs with effect size information, 49 (58.3%) had a relative difference of less than 25%.

DISCUSSION

Around 36% of the RCTs published in nursing journals did not report how they reached their sample sizes. For those that had reported, only 15% provided all the necessary parameters to re-compute their sizes. It is concluded that the methodology and parameters used for sample size determination are inadequately reported in RCTs published in nursing journals.

Relations of magnesium intake to cognitive impairment and dementia among participants in the Women's Health Initiative Memory Study: a prospective cohort study

OBJECTIVE

To examine the associations of dietary and supplemental magnesium (Mg) as assessed by a semi-quantitative food frequency questionnaire with cognitive outcomes among ageing women.

DESIGN

This work conducts a prospective cohort study of participants enrolled in the Women's Health Initiative Memory Study (WHIMS), which was subsequently extended and named WHIMS-Epidemiology of Cognitive Health.

SETTING

Forty clinical centres in the USA.

PARTICIPANTS

Postmenopausal women aged 65-79 years without dementia on enrolment.

MAIN OUTCOME MEASURES

Physician-adjudicated mild cognitive impairment (MCI) and/or probable dementia (PD).

RESULTS

Participants were excluded (n=1006) if they had extreme values of dietary energy intake, had missing or extreme body mass index values, with prevalent MCI/PD at baseline, received only one cognitive assessment or had been followed up for <1 year. During >20 years of follow-up, 765 (11.8%) out of 6473 participants developed MCI/PD. For MCI/PD and MCI, the risks tended to be lower among participants in quintiles Q2-Q5 of Mg consumption compared with those in the lowest quintile. Participants in Q3 had a significantly lower risk of MCI/PD (HR 0.69, 95% CI 0.53 to 0.91) and MCI (HR 0.63, 95% CI 0.45 to 0.87) after multivariate adjustments. No significant association was observed between total Mg intake and PD. The association between total Mg intake, MCI/PD and MCI was non-linear as suggested by the likelihood test.

CONCLUSIONS

Total Mg intake between the estimated average requirement and the recommended dietary allowances may associate with a lower risk of MCI/PD and MCI.

TRIAL REGISTRATION NUMBER

NCT00685009.