Association Between Serum Calcium and the Prevalence of Hypertension Among US Adults

Association between red cell distribution width and hypertension: Results from NHANES 1999-2018

The relationship between red cell distribution width (RDW) and hypertension remains a contentious topic, with a lack of large-scale studies focusing on the adults in the United States. This study aimed to investigate the association between RDW and hypertension among US adults from 1999 to 2018.

METHODS

Data were derived from the National Health and Nutrition Examination Survey (NHANES) 1999-2018. RDW values were obtained from the Laboratory Data's Complete Blood Count with 5-part Differential-Whole Blood module. Hypertension data were obtained through hypertension questionnaires and blood pressure measurements. Multivariable weighted logistic regression analyses were conducted to assess the association between RDW and hypertension, followed by subgroup and smooth curve analyses.

RESULTS

Compared to the non-hypertensive group, the hypertensive group exhibited higher RDW values (13.33±1.38 vs. 12.95±1.27, P <0.001). After adjusting for covariates, weighted multivariable logistic regression analysis revealed a positive correlation between RDW and hypertension prevalence (OR: 1.17, 95% CI 1.13, 1.21, P <0.001). When RDW was included as a categorical variable, participants in the fourth quartile had the highest risk of hypertension (OR: 1.86, 95% CI 1.70, 2.03, P <0.001). Subgroup analysis showed that, except for age, BMI and weak/failing kidneys, gender, race, education level, smoking, alcohol use, congestive heart failure, and stroke did not significantly influence this correlation (all P-values for interaction >0.05).Smooth curve fitting analysis revealed a reverse J-shaped relationship between RDW and hypertension prevalence, with an inflection point at 12.93%.

CONCLUSION

We first explored the relationship between RDW and hypertension among US adults and discovered a reverse J-shaped association, providing further insights into the relationship between blood cell counts and hypertension and offering a new foundation for hypertension prevention and control.

Association of plasma trans fatty acid concentrations with blood pressure and hypertension in U.S. adults

Objective

The present study aimed to evaluate the association of plasma trans fatty acids (TFAs) biomarkers with the risk of hypertension.

Methods

Using data from the National Health and Nutrition Examination Surveys (NHANES 2009-2010), we conducted a thorough analysis using both the traditional regression model and the Bayesian Kernel Machine Regression (BKMR) model to investigate the associations of individual TFAs and their mixtures with systolic blood pressure (SBP), diastolic blood pressure (DBP), and the risk of hypertension in a sample of 1,970 American adults.

Results

The concentrations of TFAs were natural logarithms (ln) transformed to approximate a normal distribution. Multivariate linear regression models showed that each 1-unit increase in ln-transformed plasma concentrations of palmitelaidic, elaidic, vaccenic, and linolelaidic acids was associated with separate 2.94-, 3.60-, 2.46- and 4.78-mm Hg and 2.77-, 2.35-, 2.03-, and 3.70- mm Hg increase in SBP and DBP, respectively (P < 0.05). The BKMR model showed positive associations between the four TFAs mixtures and SBP and DBP. In addition, linolelaidic acid contributed the most to an increased blood pressure. Similar results were observed with the threshold of hypertension (≥130/80 mm Hg).

Conclusion

Our findings provide preliminary evidence that plasma TFA concentrations are associated with increased blood pressure and the risk of hypertension in US adults. This study also suggests that linolelaidic acid might exhibit more deleterious effects on hypertension than other TFAs. Further studies should be conducted to validate these results.

Risk factors of different mortality periods in older patients with end-stage renal disease undergoing urgent-start peritoneal dialysis: a retrospective observational study

BACKGROUND

The first six months of therapy represents a high-risk period for peritoneal dialysis (PD) failure. The risk of death in the first six months is higher for older patients treated with urgent-start PD (USPD). However, there are still gaps in research on mortality and risk factors for death in this particular group of patients. We aimed to investigate mortality rates and risk factors for death in older patients with end-stage renal disease (ESRD) receiving USPD within and after six months of therapy.

METHODS

We retrospectively studied the clinical information of older adults aged ≥ 65 years with ESRD who received USPD between 2013 and 2019 in five Chinese hospitals. Patients were followed up to June 30, 2020. The mortality and risk factors for death in the first six months of USPD treatment and beyond were analyzed.

RESULTS

Of the 379 elderly patients in the study, 130 died over the study period. During the follow-up period, the highest number (45, 34.6%) of deaths occurred within the first six months. Cardiovascular disease was the most common cause of death. The baseline New York Heart Association (NYHA) class III-IV cardiac function [hazard ratio (HR) = 2.457, 95% confidence interval (CI): 1.200-5.030, p = 0.014] and higher white blood cell (WBC) count (HR = 1.082, 95% CI: 1.021-1.147, p = 0.008) increased the mortality risk within six months of USPD. The baseline NYHA class III-IV cardiac function (HR = 1.945, 95% CI: 1.149-3.294, p = 0.013), lower WBC count (HR = 0.917, 95% CI: 0.845-0.996, p = 0.040), lower potassium levels (HR = 0.584, 95% CI: 0.429-0.796, p = 0.001), and higher calcium levels (HR = 2.160, 95% CI: 1.025-4.554, p = 0.043) increased the mortality risk after six months of USPD.

CONCLUSION

Different risk factors correlated with mortality in older adults with ESRD within and after six months of undergoing USPD, including baseline NYHA class III-IV cardiac function, WBC count, potassium, and calcium levels.

Development of hypertension models for lung cancer screening cohorts using clinical and thoracic aorta imaging factors

This study aims to develop and validate nomogram models utilizing clinical and thoracic aorta imaging factors to assess the risk of hypertension for lung cancer screening cohorts. We included 804 patients and collected baseline clinical data, biochemical indicators, coexisting conditions, and thoracic aorta factors. Patients were randomly divided into a training set (70%) and a validation set (30%). In the training set, variance, t-test/Mann-Whitney U-test and standard least absolute shrinkage and selection operator were used to select thoracic aorta imaging features for constructing the AIScore. Multivariate logistic backward stepwise regression was utilized to analyze the influencing factors of hypertension. Five prediction models (named AIMeasure model, BasicClinical model, TotalClinical model, AIBasicClinical model, AITotalClinical model) were constructed for practical clinical use, tailored to different data scenarios. Additionally, the performance of the models was evaluated using receiver operating characteristic (ROC) curves, calibration curves and decision curve analyses (DCA). The areas under the ROC curve for the five models were 0.73, 0.77, 0.83, 0.78, 0.84 in the training set, and 0.77, 0.78, 0.81, 0.78, 0.82 in the validation set, respectively. Furthermore, the calibration curves and DCAs of both sets performed well on accuracy and clinical practicality. The nomogram models for hypertension risk prediction demonstrate good predictive capability and clinical utility. These models can serve as effective tools for assessing hypertension risk, enabling timely non-pharmacological interventions to preempt or delay the future onset of hypertension.

Dietary calcium is inversely associated with hepatitis B virus infection: an analysis of US National Health and Nutrition Examination Survey (NHANES) 2007-2020

BACKGROUND

There have been studies on the relationship between hepatitis B virus (HBV) infection and diet. We hypothesized HBV infection is related to dietary calcium intake, but the evidence is limited. This study aimed to examine whether dietary calcium intake is independently related to HBV infection in the United States population.

METHODS

A total of 20,488 participants aged over 20 years from the National Health and Nutrition Examination Survey (NHANES), conducted from 2007 to 2020, were included in this study. Pearson correlation was used to test the association between dietary calcium and serum calcium. The relationships of HBV infection with dietary calcium and serum calcium were assessed by logistic regression models.

RESULTS

There was a weak correlation between dietary calcium and serum calcium (r = 0.048). Logistic regression models indicated that HBV infection had a linear negative correlation with dietary calcium (OR 0.37; 95%CI 0.19, 0.76). For each additional 10 mg dietary calcium, the possibility of HBV infection was reduced by 63%. Hepatitis B positive participants had lower serum calcium content than negative participants. Stratified analysis shown the linear relationship between calcium and HBV infection varied among sex, race/ethnicity, and body mass index.

CONCLUSION

Our findings demonstrated HBV infection was linearly and inversely correlated with dietary calcium. The current study is expected to offer a fresh perspective on reducing HBV infection.

Independent associations of serum calcium with or without albumin adjustment and serum phosphorus with nonalcoholic fatty liver disease: results from NHANES 1999-2018

Background

The associations of serum calcium and phosphorus with nonalcoholic fatty liver disease (NAFLD) remain unclear. In addition, there may be an effect of albumin correction on the association between serum calcium and NAFLD. We aimed to explore these relationships in the National Health and Nutrition Examination Survey (NHANES).

Methods

Eligible adult individuals from NHANES 1999-2018 were recruited for the study. We explored the associations of serum calcium, albumin-adjusted serum calcium, and serum phosphorus with NAFLD in multivariable-adjusted regression models. In addition, restricted cubic spline (RCS), stratified analysis, and multiple sensitivity analyses were used for further elaboration.

Results

The study sample consisted of 20,900 participants, with an observed NAFLD prevalence of 44.65%. Fully adjusted models indicated that serum calcium was inversely associated with NAFLD (odds ratio [OR] and 95% confidence interval [CI] = 0.70 (0.62, 0.78), p<0.0001), whereas albumin-adjusted serum calcium was positively associated with NAFLD (OR and 95% CI=1.59 (1.41, 1.79), p<0.0001). RCS modeling indicated that serum calcium without and with albumin adjustment was linearly(p nonlinear = 0.083) and nonlinearly (p nonlinear < 0.0001) associated with NAFLD, respectively, whereas serum phosphorus showed a U-shaped relationship with NAFLD(p nonlinear < 0.0001). Gender is a significant influence in all associations, and other variables may also have an effect. Sensitivity analyses indicated that these associations were independent of additional significant confounders.

Conclusion

Serum calcium and phosphorus were significantly associated with the development of NAFLD. These findings suggest the potential clinical significance of serum calcium/phosphorus and albumin levels in individuals at high risk for NAFLD. Our study supports the potential role of serum calcium/phosphorus homeostasis in the pathophysiology of NAFLD and could serve as NAFLD-related biomarkers.

Impaired Sensitivity to Thyroid Hormones Is Associated With Decreased Vitamin D Levels in the Euthyroid Population

CONTEXT

The relationship between vitamin D and thyroid profiles lacks consensus despite extensive investigations. Whether vitamin D levels correlate with thyroid hormone sensitivity remains largely unexplored.

OBJECTIVE

To explore the relationship between vitamin D levels and thyroid hormone sensitivity among euthyroid individuals.

METHODS

This study involved 6452 euthyroid participants. Clinical parameters, including TSH, free thyroxine, 25-hydroxyvitamin D [25(OH)D], and other relevant indicators were extracted from the National Health and Nutrition Examination Survey 2007-2012. To quantify thyroid hormone sensitivity, we calculated the Thyroid Feedback Quantile-based Index (TFQI), the TSH index (TSHI), and the thyrotropin thyroxine resistance index (TT4RI).

RESULTS

Subjects with impaired thyroid hormone sensitivity have decreased 25(OH)D levels (TFQI, TT4RI: P < 0.05; TSHI: P = .05574) following adjustment of confounding variables. Age-specific analysis found negative correlations between thyroid hormone sensitivity indices and 25(OH)D within the 20 to 60 years subgroup, turning positive in the 60 to 80 years subgroup. In females, thyroid hormone sensitivity indices and vitamin D levels were negatively linked, while in males, vitamin D's relationships with TFQI, TT4RI, and TSHI shifted from negative to positive when 25(OH)D levels exceeded 63.5 nmol/L, 56.7 nmol/L, and 56.7 nmol/L, respectively. Stratification by race revealed U-shaped curvilinear patterns resembling those found in the males. In body mass index (BMI) subanalysis, vitamin D had differing associations with thyroid hormone sensitivity indices: negative in the <25 kg/m2 and ≥30 kg/m2 subgroups and U-shaped in the 25-30 kg/m2 subgroup.

CONCLUSION

Impaired thyroid hormone sensitivity correlates with decreased vitamin D levels among euthyroid subjects, with associations varying by age, sex, race, and BMI.

The hypertension and hyperlipidemia status among type 2 diabetic patients in the community and influencing factors analysis of glycemic control

OBJECTIVE

To understand the prevalence of hypertension and hyperlipidaemia as well as the current status of glycaemic control and its influencing factors among type 2 diabetes mellitus patients in the community in South China, and to provide recommendations for the prevention and control of diabetes.

METHODS

Questionnaires, physical examinations and laboratory tests were conducted on patients with type 2 diabetes mellitus who participated in the National Basic Public Health Service Programme in Guangzhou in 2020. The chi-square test, t-test and multi-factor unconditional logistic regression analysis were performed using R 4.1.2 software.

RESULT

Among 127,423 type 2 diabetic patients in Guangzhou, 57,695 achieved glycemic control standards, with a glycemic control rate of 45.28%.In this study, the proportion of T2DM patients with hypertension and hyperlipidaemia together was 27.79%, The percentage of T2DM patients with hypertension alone and hyperlipidaemia alone was 28.34% and 20.53% respectively, and the rate of no complications was 23.34%. There was a statistically significant difference in the rate of glycaemic control between the different disease combination states (P < 0.05). The glycaemic control rate was 47.67% in diabetic patients without hypertension and hyperlipidaemia, 52.54% and 37.24% in those with combined hypertension alone and hyperlipidaemia alone respectively, compared to 41.80% in diabetic patients with hypertension and hyperlipidaemia. After adjusting for all covariates, multivariate analysis showed that combined hypertension alone was associated with good glycaemic control (OR 0.817, 95% CI 0.791, 0.843, P < 0.001),when using comorbid T2DM as a control group, combined hyperlipidaemia alone, combined hypertension and hyperlipidaemia were associated with poor glycaemic control (OR 1.521, 95% CI 1.470,1.574, P < 0.001 and OR 1.250, 95% CI 1.211,1.291, P < 0.001), Subgroup analyses as well as multifactorial unconditional logistic regression analyses showed that patients with type 2 diabetes who were overweight and obese, smoked, drank alcohol, had a diagnosis of diabetes for ≥ 6 years, had fair or poor adherence and had a family history of diabetes had lower rates of glycaemic control.

CONCLUSION

The results of this study showed that the co-morbidity of hypertension and hyperlipidaemia was high and prevalent among diabetic patients in Guangzhou. Moreover, glycaemic control of T2DM patients with hyperlipidaemia was lower than other diabetic patients. Obesity and overweight, poor lifestyle and dietary habits are also major factors affecting the treatment and control of T2D patients in this region. Therefore, comprehensive measures should be actively taken to control blood glucose levels in type 2 diabetic patients by also incorporating lipid management into the community and strictly controlling lipid levels.

Association between serum calcium level and type 2 diabetes: An NHANES analysis and Mendelian randomization study

AIMS

This study investigated the association between serum calcium levels and the prevalence of T2D using a cross-sectional study and Mendelian randomization analysis.

METHODS

Cross-sectional data were obtained from the National Health and Nutrition Examination Survey (NHANES) from 1999 to 2018. Serum calcium levels were divided into three groups (low, medium and high groups) according to the tertiles. Logistic regression was used to estimate the association between serum calcium levels and T2D prevalence. Instrumental variables for serum calcium levels were obtained from the UK Biobank and a two-sample MR analysis was performed to examine the causal relationship between genetically predicted serum calcium levels and the risk of T2D.

RESULTS

A total of 39,645 participants were available for cross-sectional analysis. After adjusting for covariates, participants in the high serum calcium group had significantly higher odds of T2D (OR = 1.18, 95% CI = 1.07, 1.30, p = 0.001) than those in the moderate group. Restricted cubic spline plots showed a J-shaped curve relationship between serum calcium level and prevalence of T2D. Consistently, Mendelian randomization analysis showed that higher genetically predicted serum calcium levels were causally associated with a higher risk of T2D (OR = 1.16, 95% CI: 1.01, 1.33, p = 0.031).

CONCLUSIONS

The results of this study suggest that higher serum calcium levels are causally associated with a higher risk of T2D. Further studies are needed to clarify whether intervening in high serum calcium could reduce the risk of T2D.

Salivary Calcium Level and Its Correlation with Salivary pH, Salivary Volume, and Calcium Intake in Hypertensive Female Patients with Different Blood Sugar Levels

Aims

This study aimed to evaluate the salivary calcium level and its correlation with salivary pH, salivary volume, and calcium intake in hypertensive female patients with different blood sugar levels.

Materials and Methods

This cross-sectional study included 49 female subjects with hypertension. Subjects were divided into three groups based on the HbA1c test: normal, prediabetes, and diabetes. Unstimulated whole saliva was collected using the spitting method. Salivary calcium levels were evaluated using an Atomic Absorption Spectrophotometer. Salivary pH was obtained using a universal indicator pH paper test. Calcium intake was assessed by a semi-quantitative food frequency questionnaire. The Kruskal-Wallis test was used to compare salivary parameters and total calcium intake within study groups. Spearman rank correlation and multiple regression analysis were used to evaluate the correlation between salivary calcium levels and all variables in the study.

Results

No significant difference in salivary calcium, volume, pH, and total calcium intake was observed within the study groups. However, a significant correlation was found between salivary calcium levels and salivary pH in hypertensive females with normal blood glucose levels. Moreover, salivary calcium levels have a significant correlation with systolic blood pressure in prediabetes and diabetes groups.

Conclusions

This study found a decrease in all salivary parameters (calcium, pH, and volume) as well as a low calcium intake in hypertensive females, despite no significant difference found in groups with different blood glucose levels. Blood glucose levels appeared to be a confounder in the relationship between salivary calcium with salivary pH and systolic blood pressure.

Associations between plasma metal mixture exposure and risk of hypertension: A cross-sectional study among adults in Shenzhen, China

Background

Metal exposure affects human health. Current studies mainly focus on the individual health effect of metal exposure on hypertension (HTN), and the results remain controversial. Moreover, the studies assessing overall effect of metal mixtures on hypertension risk are limited.

Methods

A cross-sectional study was conducted by recruiting 1,546 Chinese adults who attended routine medical check-ups at the Eighth Affiliated Hospital of Sun Yat-sen University, Shenzhen. The plasma levels of 13 metals were measured using inductively coupled plasma mass spectrometry. Multivariate logistic regression model, restricted cubic spline (RCS) model and the Bayesian Kernel Machine Regression (BKMR) model were applied to explore the single and combined effect of metals on the risk of HTN.

Results

A total of 642 (41.5%) participants were diagnosed with HTN. In the logistic regression model, the adjusted odds ratios (ORs) were 0.71 (0.52, 0.97) for cobalt, 1.40 (1.04, 1.89) for calcium, 0.66 (0.48, 0.90), and 0.60 (0.43, 0.83) for aluminum in the second and third quartile, respectively. The RCS analysis showed a V-shaped or an inverse V-shaped dose-response relationship between metals (aluminum or calcium, respectively) and the risk of HTN (P for non-linearity was 0.017 or 0.009, respectively). However, no combined effect was found between metal mixture and the risk of hypertension.

Conclusions

Plasma levels of cobalt, aluminum and calcium were found to be associated with the risk of HTN. Further studies are needed to confirm our findings and their potential mechanisms with prospective studies and experimental study designs.

The Levels of Bioelements in Postmenopausal Women with Metabolic Syndrome

(1) Metabolic syndrome is a set of factors that considerably increase the risk of developing atherosclerosis, type 2 diabetes, and their cardiovascular complications. Studies show that menopause and the levels of elements may be significantly associated with increased risk of MetS. The present study evaluated the relationship between element levels (Ca, P, Na, K, Fe, Mg, Cu, Zn, Sr) and the incidence of MetS and concomitant metabolic disorders in peri-menopausal women. (2) The study involved 170 perimenopausal women. The methods used were: survey, anthropometric measurement (WC, height, BMI, WHtR), blood pressure measurement, and biochemical analysis of venous blood (lipid profile, glucose, insulin, HbA1C). (3) The study demonstrated statistically significantly higher WC, WHtR, SBP, and DBP values in women with pre-Mets than in those with Mets and the control group. Significantly higher FPG, TG, LDL, HbA1C, insulin, TG/HDL ratio, and TC/HDL ratio were recorded in the MetS group compared to the rest of respondents. In addition, post hoc analysis revealed statistically significant differences in mean K concentrations between pre-MetS and MetS women. (4) Low blood K levels in perimenopausal women are associated with an increased risk of MetS. Significantly higher Cu levels were observed in overweight women. The concentration of Cu negatively correlates with the values of TC, LDL, and SBP.

The Association Between Total Percent Fat and Serum Uric Acid in Adults

Background

Serum uric acid (SUA) has been proven to be closely associated with metabolic abnormalities, including obesity. This study aimed to investigate the detailed relationship between total percent fat (TPF) and SUA among adults.

Methods

Briefly, 23,715 adults aged 18–59 years in the National Health and Nutrition Examination Survey (NHANES) 1999–2018 were included in this study. Multivariable linear regression models were used to examine the association between TPF and SUA. Subgroup analyses stratified by sex and obesity status were also performed by multivariable linear regression. Then, fitted smoothing curves and generalized additive models were also applied to address the non-linear relationship between TPF and SUA. Finally, a recursive algorithm was used to calculate the inflection point in the non-linear relationship and a two-segment piecewise linear regression model was used to analyze the relationship between TPF and SUA on both sides of the inflection point.

Results

There were 15,808 (66.7%) obese individuals in all 23,715 participants. In the fully adjusted model, there was a positive association between TPF and SUA (β = 0.99, 95% CI: 0.73–1.26). Besides, this positive association remained statistically significant in subgroup analyses stratified by sex and obesity status. Interestingly, in males, the association of TPF and SUA was an inverted U-shaped curve (inflection point: 34.3%).

Conclusion

Our study revealed a significant positive relationship between TPF and SUA among adults and this association remained statistically significant when stratified by sex and obesity status, but the shape of the smoothing curve in males differed from that in females.

Association between serum Klotho levels and the prevalence of diabetes among adults in the United States

BACKGROUND

Diabetes is a critical contributor to the pathogenesis of cardiovascular diseases. Klotho is an anti-aging protein with cardiovascular-renal protective effects. However, the relationship between serum Klotho levels and diabetes remains poorly understood.

OBJECTIVES

This study aimed to investigate the relationship between serum Klotho levels and diabetes in US adults.

METHODS

We analyzed the cross-sectional data obtained from 13751 subjects aged 40-79 years in the National Health and Nutrition Examination Survey (NHANES) (2007-2016). Serum Klotho concentration was measured using an enzyme-linked immunosorbent assay (ELISA) and categorized into four quartiles (Q1-Q4). Multivariate logistic regression and restricted cubic spline (RCS) regression were conducted to explore the association between serum Klotho levels and the prevalence of diabetes.

RESULTS

As compared with quartile 1, serum Klotho levels in quartiles 2-4 yielded odds ratios (OR) (95% CI) of diabetes of 0.96 (0.80-1.15), 0.98 (0.82-1.18), and 1.25 (1.04-1.50), respectively, after covariate adjustment (P for trend = 0.018). The results implied an increased risk of diabetes. The RCS plot showed a U-shaped relationship linking serum Klotho levels with diabetes (P for nonlinearity = 0.003).

CONCLUSIONS

In summary, a nonlinear and positive association was found between serum Klotho levels and the prevalence of diabetes. Further study is needed to verify the causality of this association and elucidate the underlying mechanisms.