Joint effect of 25-hydroxyvitamin D and secondhand smoke exposure on hypertension in non-smoking women of childbearing age: NHANES 2007-2014

Association Between Homocysteine and All-Cause Mortality Among Osteoarthritis Patients: A Cohort Study from the NHANES Database

This study explored the association between serum Hcy level and the all-cause mortality among osteoarthritis (OA) patients. This cohort study included patients diagnosed as OA from the National Health and Nutrition Examination Survey (NHANES) 1999-2006. Abbott Homocysteine assay, a fully automated fluorescence polarization immunoassay (FPIA) method, was used to measure the level of serum Hcy. Covariates included sociodemographic information, lifestyles, history of diseases and medications were extracted from the database. The weighted univariate, multivariate Cox proportional hazard models and restricted cubic splines (RCS) were utilized to explore the association between Hcy level and all-cause mortality in OA patients, with hazard ratios (HRs) and 95% confidence intervals (CIs). Subgroup analyses based on different age, gender, duration of OA, complications and C-reactive protein (CRP) were further assessed by this association. Totally 1384 OA patients were included in this study, of which 817 (59.03%) died by 31 December 2019. After adjusting all covariates, high Hcy level was associated with the high all-cause mortality among OA patients (HR=1.31, 95%CI: 1.02-1.67), especially in females (HR=1.43, 95%CI: 1.07-1.91), aged >60 years (HR=1.49, 95%CI: 1.14-1.94), duration of OA >10 years (HR=1.40, 95%CI: 1.01-1.95), with the history of hypertension (HR=1.37, 95%CI: 1.03-1.80), without the history of diabetes (HR=1.36, 95%CI: 1.01-1.82) or CRP >0.29 mg/l (HR=1.51, 95%CI: 1.04-2.19). High serum Hcy level was associated with high risk of all-cause mortality in OA patients. Our results suggest that serum Hcy is a promising biomarker for the prognosis of OA patients.

The joint effect of vitamin-D status and tobacco exposure on overweight and obesity in children

This study aimed to explore the combined effects of serum vitamin-D level and tobacco exposure on the risk of overweight and obesity in children. This cross-sectional study analysed the data of 11 636 children aged 2-17 years from the National Health and Nutrition Examination Surveys database between 2007 and 2018. Univariable and multivariate weighted logistic regression models were used to analyse the associations of serum vitamin-D or cotinine levels with overweight and obesity in children as well as the combined effects of serum vitamin-D and cotinine on the risk of overweight and obesity in children. Subgroup analysis was performed in terms of gender, age, race and household smokers. OR with corresponding 95 % CI was presented. The elevated risk of overweight and obesity in children was found in those with serum vitamin-D < 20 ng/ml (OR = 1·44, 95 % CI: 1·29, 1·61). Also, the odds of overweight and obesity in children was 1·14 (OR = 1·14, 95 % CI: 1·01, 1·29) in children with cotinine ≥ 0·05 ng/ml. Relative to participants with serum vitamin-D ≥ 20 ng/ml and cotinine < 0·05 ng/ml, increased risk of overweight and obesity was identified in those with serum vitamin-D < 20 ng/ml and cotinine < 0·05 ng/ml (OR = 1·45, 95 % CI: 1·26, 1·68) and serum vitamin-D < 20 ng/ml and cotinine ≥ 0·05 ng/ml (OR = 1·62, 95 % CI: 1·38, 1·91). Serum vitamin-D and cotinine exposure had combined effects on the risk of overweight and obesity in children.

Inverse association between serum iron levels and Hashimoto's thyroiditis in United States females of reproductive age: analysis of the NHANES 2007-2012

Purpose

Hashimoto's thyroiditis (HT) is a significant public health concern, particularly among females. While existing studies have explored the correlation between serum iron levels and HT, limited research has specifically focused on this association in reproductive-age females. Our study aims to investigate the relationship between serum iron and HT.

Methods

Using data from the National Health and Nutrition Examination Survey (NHANES) database (2007-2012), we employed weighted multivariate logistic regression models, an XGBoost model, and smooth curve fitting. We assessed the correlation between serum iron and HT and examined linear and non-linear relationships with thyroid peroxidase antibodies (TPOAb) and thyroglobulin antibodies (TgAb).

Results

Among 2,356 participants, each unit increase in serum iron was associated with a 43% reduced risk of HT (Odds Ratios (OR) 0.574; 95% Confidence Interval (CI) 0.572, 0.576). Quartile analysis confirmed these effects. The XGBoost model identified serum iron as the most significant variable correlated with HT. Smooth curves revealed a linear association between log2-transformed serum iron and HT. Additionally, log2-transformed serum iron inversely correlated with TPOAb levels (β -15.47; 95% CI -25.01, -5.92), while a non-linear relationship was observed with TgAb.

Conclusion

Our study reveals that in reproductive-age women, every unit increase in serum iron is associated with a 43% lower risk of HT, demonstrating an inverse relationship. Additionally, serum iron exhibits a negative correlation with TPOAb and a non-linear association with TgAb.

Association between dietary inflammatory index and all-cause mortality in patients with osteopenia or osteoporosis: A retrospective cohort study from the NHANES 2007-2018

Objective

Osteoporosis is an inflammatory disease that causes a large disease burden worldwide. Dietary inflammation index (DII), a comprehensive assessment index that reflects the pro-inflammatory/anti-inflammatory level of diet was related to multiple inflammatory diseases. This study aimed to explore the association between DII and all-cause mortality in patients with osteoporosis or osteopenia.

Methods

In this retrospective cohort study, data of patients aged ≥ 45 years diagnosed as osteopenia or osteoporosis and had complete dietary intake information were extracted from the National Health and Nutrition Examination Survey (NHANES 2007-2010, 2013-2014, 2017-2018). Dietary intake information was obtained from 24-h dietary recall interviews and was used to calculate the DII score. Weighted univariate and multivariate Cox proportional hazard models were utilized to explore the association between DII and all-cause mortality in patients with osteoporosis or osteopenia, with hazard ratios (HRs) and 95 % confidence intervals (CIs). Subgroup analyses based on different age, gender and complications were further assessed this association.

Results

A total of 5,381 patients were included. Until December 31, 2019, 1,286 all-cause deaths occurred. After adjusting all covariates, high DII was associated with the high odds of all-cause mortality among patients with osteoporosis or osteopenia (HR=1.28, 95 %CI: 1.10-1.48), especially in the male (HR=1.38, 95 %CI: 1.06-1.78), aged < 65 years (HR=1.49, 95 %CI: 1.09-2.02), and without the history the cardiovascular disease (HR=1.30, 95 %CI: 1.03-1.65), diabetes mellitus (HR=1.27, 95 %CI: 1.06-1.52) and chronic kidney disease (HR=1.28, 95 %CI: 1.03-1.58).

Conclusion

A pro-inflammatory diet may have an adverse effect on the prognosis of osteoporosis patients.

Non-high-density lipoprotein cholesterol to high-density lipoprotein cholesterol ratio (NHHR) and hypertension in American adults: a NHANES cross-sectional study

Objectives

The relationship between non-high-density lipoprotein cholesterol to high-density lipoprotein cholesterol ratio (NHHR) and hypertension remains uncertain, warranting further investigation. This study aims to elucidate the association between NHHR and hypertension.

Methods

A comprehensive cross-sectional stratified survey involving 30,602 participants aged 20 years and older was conducted using the National Health and Nutrition Examination Survey (NHANES) dataset from 2001 to 2018. NHHR was calculated as [total cholesterol (TC) - high-density lipoprotein cholesterol (HDL-C)]/HDL-C. The relationship between NHHR and hypertension was examined using weighted multiple linear regression, smooth curve fitting, hierarchical analysis, and interaction testing.

Results

The mean age of participants was 49.82 ± 17.64 years, with 15,266 women included. The average NHHR was 2.94 ± 0.56. A positive correlation between NHHR and hypertension was observed. Stratification of NHHR into quartiles, in the fully adjusted Model 3, revealed that individuals in the highest NHHR quartile had a 60% increased risk of hypertension for each unit increase in NHHR compared to those in the lowest quartile. Interaction tests indicated that the relationship between NHHR and hypertension remained consistent across subgroups, except for gender, age, education, and smoking status, which influenced this association.

Conclusion

Analysis of NHANES data from 2001 to 2018 demonstrated a consistent positive association between NHHR and hypertension. NHHR may provide potential assistance in hypertension prevention and diagnosis.

Association between dietary carotenoid intakes and the risk of asthma in children and adolescents: evidence from the National Health and Nutrition Examination Survey 2007-2016

Background

In recent years, the incidence of asthma in children has been increasing. As a chronic disease, in addition to drug treatment, dietary management is also important. However, studies of carotenoids and asthma have shown mixed results. This study aimed to evaluate whether the relationship between carotenoid intake and current asthma holds significant importance.

Methods

We studied 9,118 children aged 6-16 years in the National Health and Nutrition Examination Survey (NHANES) of US from 2007 to 2016, and the relationship of dietary carotenoid and its subgroup with pediatric asthma. Current asthma was assessed by parent-reported, doctor-diagnosed, asthma using a standardized questionnaire. We used multivariate logistic regression to calculate the odds ratio (OR) for current asthma with a 95% confidence interval (CI).

Results

Total carotenoid intake was not associated with the risk of current asthma. Compared with the first quantile, the second quantile of β-cryptoxanthin intake was positively correlated with current asthma (Q2: 1.227; 95% CI: 1.025-1.470; P=0.03). The test of trend showed that, as the α-carotene intake increased, the risk of current asthma showed a decreasing trend, which was very close to the statistic confidence cutoff (Model I: P for trend =0.001; Model II: P for trend =0.003; Model III: P for trend =0.08). In subgroup analysis, family history of asthma interacted with carotenoid intake (P=0.005). The population without a family history of asthma, there were significant negative associations between carotenoid intakes and asthma (quartile 4: Model III: 0.720; 95% CI: 0.549-0.943; P=0.02).

Conclusions

In this study, pediatric current asthma was not related to total carotenoids in our total participants. Total dietary carotenoid intake has a protective effect on children without a family history of asthma. Meanwhile, β-cryptoxanthin intake is positively correlated with asthma.

Potential interaction of sugar intake and tobacco exposure on dental caries in adults-A cross-sectional study from the National Health and Nutrition Examination Survey

Background/purpose

We suspected that there might be an interaction between sugar intake and tobacco exposure on the risk of dental caries. The study aimed to investigate the associations of sugar intake or tobacco exposure with the risk of dental caries.

Materials and methods

This cross-sectional study obtained data of 18804 participants from National Health and Nutrition Examination Survey (NHANES) between 2011 and 2018. Weighted univariable and multivariable logistic regression models were applied to explore the associations of total sugar intake or tobacco exposure with the risk of dental caries. The relative excess risk of interaction (RERI), attributable proportion of interaction (API), and synergy index (SI) evaluated the interaction between total sugar intake and tobacco exposure on the risk of dental caries. The effect size of odds ratio (OR), and 95% confidence interval (CI) was inputted.

Results

The OR of dental caries in adults with cotinine >10 ng/mL was 1.59 (95%CI: 1.38-1.82). The increased risk of dental caries was found in people with total sugar >19.5%E compared to those with total sugar ≤19.5%E (OR = 1.55, 95%CI: 1.34-1.78). Compared to people with cotinine ≤10 ng/mL and total sugar ≤19.5%E, adults with cotinine >10 ng/mL and total sugar >19.5%E were correlated with elevated risk of dental caries (OR = 2.76, 95%CI: 2.29-3.33). The interaction indicators RERI was 0.980 (95%CI: 0.413-1.547), API was 0.355 (95%CI: 0.192-0.517), and SI was 2.250 (95%CI: 1.344-3.767).

Conclusion

There might be interaction between sugar intake and tobacco exposure on the occurrence of dental caries in adults.

Association between secondhand smoke exposure and serum sex hormone concentrations among US female adults: a cross-sectional analysis using data from the National Health and Nutrition Examination Survey, 2013-2016

OBJECTIVE

To estimate the association between secondhand smoke (SHS) exposure and serum sex hormone concentrations in female adults (never smokers and former smokers).

DESIGN

Cross-sectional analysis.

SETTING

US National Health and Nutrition Examination Survey, 2013-2016.

OUTCOME MEASURES

Serum sex hormone measures included total testosterone (TT) and oestradiol (E2), sex hormone-binding globulin (SHBG), the ratio of TT and E2 and free androgen index (FAI). Isotope dilution-liquid chromatography tandem mass spectrometry was used to measure serum TT and E2. SHBG was measured using immunoassay. The ratio of TT and E2 and FAI were calculated. SHS exposure was defined as serum cotinine concentration of 0.05-10 ng/mL.

PARTICIPANTS

A total of 622 female participants aged ≥20 years were included in the analysis.

RESULTS

For never smokers, a doubling of serum cotinine concentration was associated with a 2.85% (95% CI 0.29% to 5.47%) increase in TT concentration and a 6.29% (95% CI 0.68% to 12.23%) increase in E2 in fully adjusted models. The never smokers in the highest quartile (Q4) of serum cotinine level exhibited a 10.30% (95% CI 0.78% to 20.72%) increase in TT concentration and a 27.75% (95% CI 5.17% to 55.17%) increase in E2 compared with those in the lowest quartile (Q1). For former smokers, SHBG was reduced by 4.36% (95% CI -8.47% to -0.07%, p for trend=0.049) when the serum cotinine level was doubled, and the SHBG of those in Q4 was reduced by 17.58% (95% CI -31.33% to -1.07%, p for trend=0.018) compared with those in Q1.

CONCLUSION

SHS was associated with serum sex hormone concentrations among female adults. In never smokers, SHS was associated with increased levels of TT and E2. In former smokers, SHS was associated with decreased SHBG levels.

The roles of serum vitamin D and tobacco smoke exposure in insomnia: a cross-sectional study of adults in the United States

Aim

Tobacco smoke exposure and vitamin D (VD) status were both associated with insomnia. However, the combined effect of smoking and VD on insomnia has not been discussed. This study aimed to explore the role of VD in the association between tobacco smoke exposure and insomnia.

Methods

Data on adults were extracted from the National Health and Nutrition Examination Surveys (NHANES) database in 2005-2008 for this cross-sectional study. Weighted univariate and multivariate logistic regression analyses were used to explore the associations between serum cotinine, serum VD, and insomnia. A surface diagram was drawn to reflect the effect of VD on the association between serum cotinine and insomnia. In addition, the potential regulating effect of VD in subgroups of smoking status was also performed. The evaluation index was odds ratios (ORs) with 95% confidence intervals (CIs).

Results

Among the eligible participants, 1,766 had insomnia. After adjusting for covariates, we found that elevated serum cotinine levels were associated with higher odds of insomnia [OR = 1.55, 95% CI: (1.22, 1.97)]. However, the relationship between serum VD level and insomnia was not significant (P = 0.553). Higher serum cotinine levels were also associated with higher odds of insomnia [OR = 1.52, 95% CI: (1.17, 1.98)] when serum VD level was <75 nmol/L; however, this relationship became non-significant when serum VD concentration was elevated (P = 0.088). Additionally, the potential regulating effect of VD was also found in adults who were not smoking.

Conclusion

VD may play a potential regulative role in the association between tobacco smoke exposure and insomnia. Further studies are needed to clarify the causal relationships between VD, tobacco smoke exposure, and insomnia.

Adherence to the Mediterranean diet regulates the association between osteopenia and the risk of all-cause mortality in general population

BACKGROUND

This study aimed to explore the association of adherence to the Mediterranean diet (MD), osteopenia and the risk of all-cause mortality in general population.

METHODS

This retrospective cohort study included 5452 participants ≥ 50 years from the National Health and Nutrition Examination Survey (NHANES). The associations of osteopenia and adherence to the MD with all-cause mortality, as well as the interaction and moderating effects between the osteopenia and adherence to the MD on the all-cause mortality, were explored via univariate and multivariable Cox proportional hazards models.

RESULTS

The follow-up was from October 1, 2006, to December 31, 2019. The median survival time of patients was 81 months. In total, 4724 people were survived and 728 were dead. Osteopenia was associated with increased risk of all-cause mortality in people [hazards ratio (HR) = 1.57, 95% confidence interval (CI) 1.23-1.99]. No significant risk of all-cause mortality was found in people with high adherence to the MD compared with those with low adherence to the MD (P > 0.05). Compared to subjects with no osteopenia who had high adherence to the MD, osteopenia people who had high adherence to the MD (HR = 1.52, 95% CI 1.17-1.98) or low adherence to the MD (HR = 1.81, 95% CI 1.23-2.66) were at increased risk of all-cause mortality after adjusting for confounding factors. The relationship between osteopenia and the risk of all-cause mortality was decreased in those with high adherence to the MD (HR = 1.57, 95% CI 1.17-2.11) compared with those with low adherence to the MD (HR = 1.62, 95% CI 1.08-2.41) after adjusting for confounding factors.

CONCLUSION

The adherence to the MD regulated the association between osteopenia and the risk of all-cause mortality, which suggested the importance of adherence to the MD in those with osteopenia, and the MD could be advocated in general people.

Association of remnant cholesterol with hypertension, type 2 diabetes, and their coexistence: the mediating role of inflammation-related indicators

PURPOSE

Cholesterol metabolism is a risk factor for cardiovascular disease, and recent studies have shown that cholesterol metabolism poses a residual risk of cardiovascular disease even when conventional lipid risk factors are in the optimal range. The association between remnant cholesterol (RC) and cardiovascular disease has been demonstrated; however, its association with hypertension, type 2 diabetes mellitus (T2DM), and the concomitance of the two diseases requires further study. This study aimed to evaluate the association of RC with hypertension, T2DM, and both in a large sample of the U.S. population, and to further explore the potential mechanisms involved.

METHODS

This cross-sectional study used data from the 2005-2018 cycles of the National Health and Nutrition Examination Survey (N = 17,749). Univariable and multivariable logistic regression analyses were performed to explore the relationships of RC with hypertension, T2DM, and both comorbidities. A restricted cubic spline regression model was used to reveal the dose effect. Mediation analyses were performed to explore the potential mediating roles of inflammation-related indicators in these associations.

RESULTS

Of the 17,749 participants included (mean [SD] age: 41.57 [0.23] years; women: 8983 (50.6%), men: 8766 (49.4%)), the prevalence of hypertension, T2DM, and their co-occurrence was 32.6%, 16.1%, and 11.0%, respectively. Higher RC concentrations were associated with an increased risk of hypertension, T2DM, and their co-occurrence (adjusted odds ratios for per unit increase in RC were 1.068, 2.259, and 2.362, and 95% confidence intervals were 1.063-1.073, 1.797-2.838, and 1.834-3.041, respectively), with a linear dose-response relationship. Even when conventional lipids were present at normal levels, positive associations were observed. Inflammation-related indicators (leukocytes, lymphocytes, monocytes, and neutrophils) partially mediated these associations. Among these, leukocytes had the greatest mediating effect (10.8%, 14.5%, and 14.0%, respectively).

CONCLUSION

The results of this study provide evidence that RC is associated with the risk of hypertension, T2DM, and their co-occurrence, possibly mediated by an inflammatory response.

Joint effect of overweight/obesity and tobacco exposure on hypertension in children aged 6-17 years: a cross-sectional study

Aim

To assess the individual effects of overweight/obesity and tobacco exposure, and their combined effects on hypertension in children.

Methods

This cross-sectional study included 6,339 children aged 6-17 years from National Health and Nutrition Examination Surveys 1999-2018. Participants' height, weight and blood pressure (BP) were measured by trained technicians. Hypertension was defined as: mean systolic BP (SBP) and/or diastolic BP (DBP) ≥ 90th percentile for sex, age, and height (for children aged 1-13 years), and SBP ≥120 mmHg and/or a DBP ≥80 mmHg (for adolescents aged 13-17 years); or self-reported having been diagnosed with hypertension or taking antihypertensive medication. Gender- and age-specific body mass index (BMI) cut-points were used to define overweight/obesity: "overweight" was defined as a BMI > 1 standard deviation (SD); "obesity" was defined as BMI > 2SD; and "thinness" was defined as BMI < -2SD. Tobacco exposure was defined as having serum cotinine levels >0.05 µg/L or reporting the presence of at least one smoker in the household. Weighted univariate and multivariate logistic regression models were used to assess overweight/obesity and tobacco exposure with the odds of hypertension, and the combined effects of overweight/ obesity and tobacco exposure on hypertension, followed by strata-specific analyses. Odds ratios (OR) with 95% confidence intervals (CI) were calculated.

Results

The prevalence of overweight/obesity and tobacco exposure was significantly higher in the hypertension group than in the non-hypertension group. Overweight/obesity (OR = 1.67, 95%CI: 1.26-2.21/ OR = 2.38, 95%CI: 1.67-3.39) and tobacco exposure (OR = 1.58, 95%CI: 1.16-2.14) were associated with a higher odd of hypertension in children, respectively. Additionally, we also observed the combined effect between overweight (OR = 3.05, 95%CI: 1.96-4.75)/obesity (OR = 3.68, 95%CI: 2.24-6.03) and tobacco exposure were related to hypertension odds in children, with a significant effect in different populations.

Conclusion

There may exist joint effect of overweight/obesity and tobacco exposure on the odds of hypertension in American children. These findings offer an insight that early weight control and reduction of tobacco exposure may be important to reduce odds of hypertension in children.

Synergistic effects of overweight/obesity and high hemoglobin A1c status on elevated high-sensitivity C-reactive protein in Chinese adults: a cross-sectional study

Background

High-sensitivity C-reactive protein (hs-CRP) is an inflammatory marker that has been suggested as a predictor of cardiovascular diseases. High glycated hemoglobin (HbA1c) levels and overweight/obesity are independently associated with elevated hs-CRP; meanwhile, high HbA1c levels are frequently accompanied by overweight or obesity. However, their joint effect on elevated hs-CRP levels has not been well-established. Therefore, we evaluated whether overweight/obesity modified the association between high HbA1c levels and elevated hs-CRP.

Methods

Based on cross-sectional data from the Chinese Urban Adults Diet and Health Study (CUADHS) in 2016, we included 1,630 adults aged 18-75 years (mean age 50.16 years and 33.6% male). Elevated hs-CRP was defined as serum hs-CRP ≥ 3 and <10 mg/L. The interactive effects of BMI and HbA1c levels on the risk of elevated hs-CRP levels were calculated by using multiple logistic regression models, followed by strata-specific analyses.

Results

Individuals with elevated hs-CRP had a higher rate of HbA1c level than those without elevated (25.3 vs. 11.3%, P < 0.001), as well as a higher rate of overweight/obesity (67.1 vs. 43.5%, P < 0.001). Higher HbA1c levels were independently associated with an increased risk of elevated hs-CRP [adjusted odds ratio (aOR) = 2.31, 95% confidence interval (CI): 1.47, 3.65], as well as overweight/obesity with the risk of elevated hs-CRP (aOR = .31, 95% confidenc-3.73). Furthermore, overweight/obesity showed a significant synergistic effect on high HbA1c levels with a higher aOR of 5.25 (2.77, 9.95) (P_interaction < 0.001). This synergistic effect was more prominent when stratified by age (in 18-44 years old, aOR, 95% CI = 30.90, 4.40-236.47 for interaction vs. 6.46, 1.38-30.23 for high HbA1c only) and gender (in women, aOR, 95% CI = 8.33, 3.80-18.23 for interaction vs. 2.46,1.38-4.40 for high HbA1c only).

Conclusion

There are synergistic effects of high HbA1c levels and overweight/obesity on the risk of elevated hs-CRP in Chinese adults, with more significant effects in adults aged 18-44 years or females. Intervention strategies for preventing high blood glucose levels and body weight simultaneously may be important for reducing hs-CRP-related diseases. Further studies are needed to confirm this finding in other populations, and its molecular mechanisms need to be elucidated.

Association between soluble transferrin receptor and systolic hypertension in adults: National Health and Nutrition Examination Survey (2007-2010 and 2015-2018)

Background

Hypertension increases the global burden of disease and mortality. Iron metabolism is considered to be an important factor in hypertension. However, as an indicator of iron metabolism, little is known about the associations of soluble transferrin receptor (sTfR) with hypertension. We studied the relationship between sTfR and hypertension.

Materials and methods

We studied 7,416 adults aged 20 years old or above from the National Health and Nutrition Examination Survey (NHANES), a nationally representative, cross-sectional, population-based study. Weighted logistic regression was used to examine the association between markers of iron metabolism and hypertension. The restricted cubic spline (RCS) was used to characterize the association between sTfR and blood pressure.

Results

Weighted logistic regression showed that higher sTfR level was associated with higher odds of hypertension (OR = 1.05; 95% CI: 1.01-1.05; p = 0.001) after adjustment for all the potential confounding factors. Meanwhile, weighted logistic regression analyses indicated independent associations of high sTfR (p = 0.009) with systolic hypertension after adjusting for various different confounders. The result of restricted cubic splines showed a non-linear association between sTfR and systolic blood pressure among U.S. adults.

Conclusion

Soluble transferrin receptor was found to be an independent factor in systolic hypertension. And, a non-linear relationship between sTfR and systolic blood pressure was discovered.

Prevalence of Vitamin D and Calcium Deficiency and Insufficiency in Women of Childbearing Age and Associated Risk Factors: A Systematic Review and Meta-Analysis

Vitamin D deficiency and insufficiency as well as low serum calcium levels can trigger negative health outcomes in women of childbearing age. Therefore, we aimed to estimate the prevalence of serum vitamin D and calcium deficiencies and insufficiencies and associated risk factors in Brazilian women of childbearing age and to assess whether there are differences in prevalence according to regions of the country and the presence or absence of pregnancy. The systematic literature review was performed using the following databases: PubMed, LILACS, Embase, Scopus, and Web of Science. Cross-sectional, cohort, and intervention studies were included. Among pregnant women, the prevalence of vitamin D deficiency ranged from 0% to 27% and of vitamin D insufficiency from 33.9% to 70.4%. Among non-pregnant women, the prevalence of vitamin D deficiency ranged from 0% to 41.7% and of vitamin D insufficiency from 38.5% to 69.3%. We found a high prevalence of vitamin D deficiency and insufficiency in women of childbearing age, with insufficiency affecting more than half of these women. The highest prevalence of vitamin D deficiency and insufficiency was observed in the South region. It was not possible to assess the prevalence and factors associated with calcium deficiency.

Comparison of Vitamin D Levels and Related Factors in Pregnant Women and Neonates Exposed to Second-Hand Smoke

Introduction: Exposure to second-hand smoke, a significant public health issue today, may lead to various health problems, especially in pregnant women and their infants. Low vitamin D levels during pregnancy may lead to preeclampsia and gestational diabetes in the mother, while it may cause low birth weight and respiratory problems in the infant.

Method: The study group consisted of 42 mothers, who smoked regularly, and their infants and 45 mothers (passive smokers), who were regularly exposed to second-hand smoke in their home environment, although they did not smoke, and their infants. Meanwhile, the control group consisted of 46 healthy mothers, who did not smoke and were not exposed to second-hand smoke at home, and their infants with similar gestational age and birth weight. Blood samples were taken as two different samples, from the mother and the baby, and 25-hydroxyvitamin D (25(OH)D) and related blood parameters were studied and compared statistically.

Results: 25(OH)D, calcium, and magnesium levels of mothers who smoked were significantly lower than those who were exposed to second-hand smoke and those who did not. Moreover, the vitamin D levels of mothers and babies exposed to second-hand smoke in the non-smoker group were significantly lower than mothers and babies who were not exposed to second-hand smoke. In the babies of these three groups, a significant decrease was observed only in vitamin D levels.

Conclusion: The present study shows that pregnant women and their infants exposed to second-hand smoke have lower vitamin D levels. Hence, more emphasis should be put on vitamin D monitoring and supplementation to prevent severe health problems in pregnant women and their infants exposed to tobacco smoke. Further studies are needed to assess the associated risks for maternal and fetal health as well as possible long-term implications for the infant.

Association of Serum 25(OH)D with Metabolic Syndrome in Chinese Women of Childbearing Age

Objective: To analyze the associations between serum 25(OH)D levels and the risk of metabolic syndrome (MetS) and its components, and the related genetic and non-genetic factors in non-diabetic women of childbearing age in China. Methods: Subjects were randomly selected from the 2015 Chinese Adult Chronic Disease and Nutrition Surveillance. The data of sociodemographic characteristics and lifestyle factors were obtained through questionnaire survey. Anthropometry was measured by trained interviewers, and fasting blood was collected to test 25-hydroxyvitamin D [25(OH)D], total cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), fasting blood glucose (FBG), and other related parameters. Generalized linear mode and multivariate logistic analysis were performed to analyze the associations between serum 25(OH)D and MetS and its components, adjusting for the possible confounders. Results: Body mass index (BMI), serum alanine aminotransferase (ALT), hypersensitive C-reactive protein (hs-CRP), 25(OH)D, phosphorus (P), and parathyroid hormone (PTH) levels were associated with the number of MetS’s components. G allele carriers of GC rs2282679 had higher diastolic blood pressure (DBP) and FBG levels compared with the TT genotypes, while higher genetic risk score (GRS) seemed to be associated with reduced HDL-C level. The odds ratio (OR) for MetS in lowest group of 25(OH)D was 1.533 (0.980−2.399) after adjusting for season, district, area type, latitude, age, BMI, PTH, P, ALT, CRE, interleukin-6 (IL-6), and hs-CRP, compared with the median group, but the association was not significant. An insufficient 25(OH)D concentration (<14.22 ng/mL) was significantly related to the risk of elevated waist circumference (WC) (OR = 1.612 (1.014−2.561)) and TG (OR = 2.210 (1.318−3.706)), and reduced HDL-C (OR = 1.639 (1.206−2.229)) after adjusting for the confounders among these women. Moreover, these relationships were not affected by vitamin D metabolism-related gene polymorphisms. Conclusion: After comprehensively considering various influencing factors, significant associations between insufficient serum 25(OH)D and MetS‘s components, including elevated WC, TG, and reduced HDL-C, were observed. However, MetS, hypertension, and hyperglycemia were not found independently associated with 25(OH)D levels.

Association between Sensitivity to Thyroid Hormone Indices and Bone Mineral Density in US Males

OBJECTIVES

Thyroid hormone is acknowledged as a pivotal factor in skeletal development and adult bone maintenance. However, available data about the relationship between sensitivity to thyroid hormone and bone mineral density (BMD) remain limited and conflicting. The purpose of the study was to explore the complex relationship between sensitivity to thyroid hormone indices and BMD using cross-sectional analysis.

METHODS

An overall sample of 3,107 males from the National Health and Nutrition Examination Survey (NHANES) was studied in the study. The thyroid hormone sensitivity indices included free triiodothyronine/tree thyroxine (FT3/FT4), thyroid-stimulating hormone index (TSHI), thyrotroph thyroxine resistance index (TT4RI), and thyroid feedback quantile-based index (TFQI). Given the complex study design and sample weights, the correlation between sensitivity to thyroid hormone indices and BMD was evaluated through multivariate linear regression models, and extra subgroup analyses were performed to examine the robustness of the results.

RESULTS

Among the 3,107 participants, we demonstrated that FT3/FT4 was negatively correlated with lumbar BMD (β = -0.0.35, 95% CI: -0.084-0.013, P < 0.05). In the terms of central sensitivity to thyroid hormone, TFQI showed a significant negative relationship with the BMD of the lumbar (β = -0.018, 95% CI: -0.033 to -0.003, P < 0.05), total femur (β = -0.020, 95% CI: -0.035 to -0.006, P < 0.01), and femur neck (β = -0.018, 95% CI: -0.031 to -0.005, P < 0.01). In the subgroup analyses stratified by body mass index (BMI), the significant negative correlation between TFQI and lumbar BMD remained in the male participants with BMI between 18.5 and 24.9 kg/m².

CONCLUSIONS

Decreased indices of sensitivity to thyroid hormones are strongly associated with increased lumbar BMD, suggesting that the dysfunction of peripheral and central response to thyroid hormone might contribute to bone loss. In addition, FT3/FT4 and TFQI were considered to be the preferable indicators to guide the prevention and clinical treatment of osteoporosis.