Single Spot Urine Sample Research Articles

Renal tubular damage as an independent risk factor for all-cause and cardiovascular mortality in a community-based population: the Takahata study.

Renal tubular damage plays a crucial role in the development of end-stage kidney disease, a risk factor for cardiovascular events and mortality. However, the relationship between renal tubular damage and all-cause and cardiovascular mortality rates in the general population remains unclear. To address this gap, we conducted a cohort study in the general population using the urinary β2-microglobulin-creatinine ratio (UBCR) as a marker of renal tubular damage. This study included 3427 residents aged ≥ 40years in Takahata, Japan. We examined the association between the UBCR values in single-spot urine samples at enrollment and all-cause and cardiovascular mortality rates within a median follow-up of 9.2years. The participants were divided into two groups based on their UBCR levels (< 300μg/g and ≥ 300μg/g groups). Kaplan-Meier analysis showed a significantly higher incidence of all-cause and cardiovascular mortality rates in the high UBCR group (log-rank P < 0.01). Multivariable Cox proportional hazards model adjusted for age, sex, estimated glomerular filtration rate (eGFR), urine albumin level, smoking, and comorbidities showed a significantly higher hazard ratio of 1.49 (95% confidence interval (CI) 1.10-2.03, P = 0.01) for all-cause mortality and a hazard ratio of 1.73 (95% CI 1.00-2.98, P = 0.048) for cardiovascular mortality in the high-UBCR group. The net reclassification index was significantly improved by adding a high UBCR to the conventional risk factors. UBCR is an independent risk factor for all-cause and cardiovascular mortality in the general population, independent of eGFR and urinary albumin levels.

Associations between urinary level of bisphenol A, phthalates, 8-iso-prostaglandin-F2α, and emotional and behavioral problems among Chinese adolescents

BackgroundEmotional and behavioral problems (EBPs) of adolescents is a worldwide public health problem. Bisphenol A (BPA) and phthalate (PAEs) are prevalent and potentially toxic to human health. Therefore, this study aimed to investigate the associations between urinary level of BPA, PAEs, 8-iso-prostaglandin-F2α (8-iso-PGF2α), and EBPs. MethodsA total of 865 Chinese adolescents were included in this study and EBPs was assessed using the Strengths and Difficulties Questionnaire (SDQ). Urinary concentrations of BPA and seven PAEs metabolites in adolescents were determined by high performance liquid chromatography-tandem mass spectrometry. Urinary 8-iso-PGF2α concentration was detected by enzyme-linked immunosorbent assay (ELISA). Spearman rank correlation analysis, multivariate logistic regression analysis, restricted cubic spline functions were used to explore the relationship between the levels of BPA, PAEs, 8-iso-PGF2α and EBPs. ResultsBPA and PAEs metabolites were positively associated with EBPs in Chinese adolescents. And the 8-iso-PGF2α was significantly non-linearly correlated with emotional symptoms, conduct problems, peer problems and total difficulties. Furthermore, 8-iso-PGF2α may partially mediate the association between BPA and PAEs exposure and EBPs. LimitationsThis study was a cross-sectional study, the cause-effect relationship between BPA, PAEs exposure and EBPs could not be determined. A single spot urine sample for BPA and PAEs exposure characterization maybe could not represent their long-term exposure level. ConclusionsHigh exposure of BPA and PAEs are associated with EBPs, which may be partly mediated by oxidative stress among adolescents. The results of this study could provide certain ideas for subsequent related research.

Sodium Intake and Atopic Dermatitis

The association of diet with atopic dermatitis (AD) remains poorly understood and could help explain heterogeneity in disease course. To determine the extent to which a higher level of dietary sodium intake, estimated using urine sodium as a biomarker, is associated with AD in a large, population-based cohort. This cross-sectional study of adult participants (aged 37-73 years) from the UK Biobank examined 24-hour urine sodium excretion, which was estimated using a single spot urine sample collected between March 31, 2006, and October 1, 2010, and calculations from the sex-specific International Cooperative Study on Salt, Other Factors, and Blood Pressure equation, incorporating body mass index; age; and urine concentrations of potassium, sodium, and creatinine. The data were analyzed between February 23, 2022, and March 20, 2024. The primary exposure was 24-hour urinary sodium excretion. The primary outcome was AD or active AD based on diagnostic and prescription codes from linked electronic medical records. Multivariable logistic regression models adjusted for age, sex, race and ethnicity, Townsend Deprivation Index, and education were used to measure the association. The analytic sample comprised 215 832 participants (mean [SD] age, 56.52 [8.06] years; 54.3% female). Mean (SD) estimated 24-hour urine sodium excretion was 3.01 (0.82) g per day, and 10 839 participants (5.0%) had a diagnosis of AD. Multivariable logistic regression revealed that a 1-g increase in estimated 24-hour urine sodium excretion was associated with increased odds of AD (adjusted odds ratio [AOR], 1.11; 95% CI, 1.07-1.14), increased odds of active AD (AOR, 1.16; 95% CI, 1.05-1.28), and increased odds of increasing severity of AD (AOR, 1.11; 95% CI, 1.07-1.15). In a validation cohort of 13 014 participants from the National Health and Nutrition Examination Survey, a 1 g per day higher dietary sodium intake estimated using dietary recall questionnaires was associated with a higher risk of current AD (AOR, 1.22; 95% CI, 1.01-1.47). These findings suggest that restriction of dietary sodium intake may be a cost-effective and low-risk intervention for AD.

Temporal trends in exposure to parabens, benzophenones, triclosan, and triclocarban in adult females in Kyoto, Japan, from 1993 to 2016.

Products used in daily life can contain chemicals such as parabens, benzophenones, triclosan, and triclocarban that have potential endocrine-disrupting effects. Little is known about the temporal trends of exposure levels to some of these chemicals in Japan. Our study assessed the intake and risk associated with exposure to commonly used chemicals. We measured the concentrations of five parabens, four benzophenones, and triclosan and triclocarban in 133 single spot urine samples. The urine samples were collected in 1993, 2000, 2003, 2009, 2011, and 2016 from healthy female residents in Kyoto, Japan. With the exception of methylparaben, ethylparaben, and butylparaben, there were no significant fluctuations in the concentrations of target chemicals over the study period; however, methylparaben, ethylparaben, and butylparaben showed temporal changes in concentrations. Methylparaben concentrations peaked in 2003 with a median value of 309μg/g creatinine, ethylparaben concentrations peaked in 1993 with a median value of 17.3μg/g creatinine, and butylparaben showed a decline, with the median values becoming non-detectable in 2009 and 2016. We calculated estimated daily intakes and hazard quotients for each chemical. In the analysis of total samples, 2.3% (3 samples) for butylparaben and 0.8% (1 sample) for propylparaben were found to surpass a hazard quotient of 1. Overall, 3% (n = 4) of the study participants exceeded a hazard index of 1. The potential health risks associated with exposure to butylparaben and propylparaben emphasize the need for further monitoring and research.

Cross-sectional associations between phthalates, phenols, and parabens with metabolic syndrome risk during early-to-mid adolescence among a cohort of Mexican youth

BackgroundEpidemiological studies on children and adults have linked toxicants from plastics and personal care products to metabolic disruption. Yet, the impact of endocrine-disrupting chemicals (EDCs) on adolescent metabolic syndrome (MetS) risk during early and mid-adolescence is unclear. MethodsTo examine the links between exposure to EDCs and MetS risk and its components, cross-sectional data from 344 Mexican youth in early-to-mid adolescence (10–17 years) were analyzed. Urinary biomarker concentrations of phthalates, phenol, and paraben analytes were measured from a single spot urine sample collected in 2015; study personnel obtained anthropometric and metabolic measures. We examined associations between summary phthalates and metabolites, phenol, and paraben analytes with MetS risk z-scores using linear regression, adjusted for specific gravity, sex, age, pubertal status, smoking, alcohol intake, physical activity level, and screen time. As a secondary aim, mediation analysis was conducted to evaluate the role of hormones in the association between summary phthalates with lipids and MetS risk z-scores. ResultsThe mean (SD) age was 13.2 (1.9) years, and 50.9% were female. Sex-stratified analyses revealed associations between summary phthalates and lipids ratio z-scores, including Σ DEHP [β = 0.21 (95% CI: 0.04, 0.37; p < 0.01)], phthalates from plastic sources (Σ Plastic) [β = 0.22 (95% CI: 0.05, 0.39; p < 0.01)], anti-androgenic phthalates (Σ AA) [β = 0.22 (95% CI: 0.05, 0.39; p < 0.01)], and individual phthalate metabolites (MEHHP, MEOHP, and MECPP) among males. Among females, BPA [β = 0.24 (95% CI: 0.03, 0.44; p < 0.05)] was positively associated with lipids ratio z-score and one phenol (2,5 DCP) [β = 0.09 (95% CI: 0.01, 0.18); p < 0.05)] was associated with increased waist circumference z-score. Results showed no evidence of mediation by hormone concentrations in the association between summary phthalates with lipids ratio or MetS risk z-scores. ConclusionHigher EDC exposure was positively associated with serum lipids during adolescence, particularly among males.

Prenatal exposures to isoflavones and neurobehavioral development in children at 2 and 4 years of age: A birth cohort study

Isoflavones (ISOs) are plant-derived estrogen-like compounds, which were already proved with cognition benefits on elderly people. However, studies assessing the associations between prenatal ISOs exposure and children’s neurodevelopment are scarce. This study aimed to examine the associations between maternal urinary ISOs concentrations, including genistein (GEN), daidzein (DAD), glycitein (GLY), and metabolite equol (EQU), and children’s neurodevelopment, based on a Chinese cohort study. Participants in this study were pregnant women recruited at 12–16 weeks of gestation, and they provided a single spot urine sample for the ISOs assay. Neurodevelopment was measured using the Child Behavior Checklist (CBCL) at 2 and 4 years of age. Negative binomial regression analysis and Generalized Estimating Equation (GEE) were performed to examine the associations between maternal urinary ISOs concentrations and CBCL scores. Associations were observed between moderate levels of prenatal ISOs exposure and decreased risks of childhood neurobehavioral problems, while the highest level of prenatal ISOs exposure was associated with increased risks of neurobehavioral problems among children. The neuroprotective effects were consistently between moderate DAD exposure and specific neurobehavioral problems, across different ages and sexes. For example, compared with the lowest exposure level, the third quartile group was associated with less Anxious/Depressed problems in boys at 2 years of age (RR=0.72 (95%CI: 0.52, 0.99)), girls at 2 years of age (RR=0.70 (95%CI: 0.46, 1.06)), boys at 4 years of age (RR=0.73 (95%CI: 0.55, 0.96)), and girls at 4 years of age (RR=0.95 (95%CI: 0.68, 1.31)).

A Cohort Study on the Effects of Maternal High Serum Iodine Status During Pregnancy on Infants in Terms of Iodine Status and Intellectual, Motor, and Physical Development.

The objective of the present study was to explore the effects of maternal iodine excess during pregnancy on infants' neurodevelopment and physical development. A total of 143 mother-child pairs were enrolled in this cohort study. Maternal blood samples were collected during the obstetric examination. A mother-child questionnaire survey was conducted, and infants' blood samples were collected during the newborn physical examination. Infants' single-spot urine samples were collected, and intellectual, motor, and physical development were assessed at 2months of age. The median (IQR) maternal serum iodine concentrations (SICs) in the first, second, and third trimesters of pregnancy were 91.2 (74.4, 102.2) μg/L, 81.2 (70.6, 94.8) μg/L, and 82.0 (68.9, 100.3) μg/L, respectively. In the first trimester of pregnancy, infants' psychomotor developmental index (PDI), body mass index (BMI) and weight-for-length Z score (WLZ) were higher with maternal suitable SIC (40 ~ 92μg/L) than with maternal excess SIC (P < 0.05). Infants' PDI, BMI, weight-for-age Z score (WAZ) and WLZ were negatively correlated with maternal SIC (P < 0.05). Maternal excess SIC had a slightly negative effect on infants' MDI (OR = 1.304, P = 0.035, 95% CI = 1.019 ~ 1.668), PDI (OR = 1.124, P = 0.001, 95% CI = 1.052 ~ 1.200) and BMI (OR = 0.790, P = 0.005, 95% CI = 0.669 ~ 0.933). In the third trimester, infants' length-for-age Z score (LAZ) was higher with maternal high SIC (> 92μg/L) (P = 0.015), and maternal SIC was positively correlated with infants' urine iodine concentration (UIC) (P = 0.026). Maternal iodine excess in the first trimester had a slightly negative effect on infants' intellectual, motor, and physical development. In the third trimester, maternal iodine excess only may have a positive impact on infants' height. Additionally, maternal iodine status was closely related to infants' iodine status.

Associations between exposure to phthalates, phenols, and parabens with objective and subjective measures of sleep health among Mexican women in midlife: a cross-sectional and retrospective analysis.

Endocrine-disrupting chemicals (EDCs) may impact sleep during the menopausal transition by altering sex hormones. However, these studies are scarce among Latin American women. This investigation utilized cross-sectional and retrospective data from midlife women enrolled in the Early Life Exposure in Mexico to Environmental Toxicants (ELEMENT) study to examine associations between exposure to EDCs (phthalates, phenols, and parabens) and sleep health measures. For cross-sectional analyses, single spot urine samples were collected between 2017-2019 from a pilot sample of women (N = 91) of midlife age to estimate the urinary concentration of individual phthalates, phenols, and parabens and to calculate the summary concentration of phthalate mixtures. Seven-day nightly sleep duration, midpoint, and fragmentation were obtained from wrist-actigraphy devices and estimated from the actigraphy data using a pruned dynamic programming algorithm. Self-reported poor sleep quality was assessed by one item from the Pittsburgh Sleep Quality Index (PSQI). We examined associations between urinary summary phthalate mixtures, phthalate metabolites, phenol, and paraben analytes with each sleep measure using linear or logistic (to compute odds of poor sleep quality only) regression models adjusted for specific gravity, age, and socioeconomic status. We ran similar regression models for retrospective analyses (N = 74), except that urine exposure biomarker data were collected in 2008 when women were 24-50years old. At the 2017-2019 midlife visit, 38% reported poor sleep quality. Cross-sectionally, EDCs were associated with longer sleep duration, earlier sleep timing, and more fragmented sleep. For example, every 1-unit IQR increase in the phenol triclosan was associated with a 26.3min per night (95% CI: 10.5, 42.2; P < 0.05) longer sleep duration and marginally associated with 0.2 decimal hours (95% CI: -0.4, 0.0; P < 0.10) earlier sleep midpoint; while every 1-unit IQR increase in the phthalate metabolite MEHP was associated with 1.1% higher sleep fragmentation (95% CI: 0.1, 2.1; P < 0.05). Retrospective study results generally mirrored cross-sectional results such that EDCs were linked to longer sleep duration, earlier sleep timing, and more fragmented sleep. EDCs were not significantly associated with odds of self-reported poor sleep quality. Results from cross-sectional and retrospective analyses revealed that higher exposure to EDCs was predictive of longer sleep duration, earlier sleep timing, and more fragmented sleep among midlife women.

Temporal trends in bisphenol exposures and associated health risk among Japanese women living in the Kyoto area from 1993 to 2016

BackgroundBisphenols, and especially bisphenol A, are widely used as components of epoxy resins and polycarbonate. Widespread detection and potential health risks have led to bisphenol A being replaced by other alternatives, including structurally similar bisphenol analogs. Several bisphenol analogs are suspected to have similar adverse health consequences. This study examined the temporal trends in bisphenol exposure among a group of Japanese women from 1993 to 2016, and assessed the associated health risks. MethodsWe used archived single spot urine samples of healthy Japanese women living in the Kyoto area (n = 133) collected in 1993, 2000, 2003, 2009, 2011, and 2016. We measured the concentrations of 10 bisphenols in these samples. ResultsA sharp increase in the detection rates of bisphenol F was observed after 2000. There was a distinct downward trend in urinary bisphenol A concentrations and an upward trend in bisphenol E concentrations after 2009. While the hazard index for all measured bisphenols was below 1 in all subjects, bisphenol F was determined as the most important risk driver after 2000, rather than bisphenol A. DiscussionTrends of decreasing bisphenol A and increasing bisphenol E exposure especially after 2011, along with no significant change in the sum of all bisphenol analogs in urine, provide clear evidence that bisphenol A has been replaced by other bisphenols in the study population. We found no significant change in the total exposure to bisphenols during the study period. Bisphenol F might become the most important bisphenol in terms of risk, while cumulative risks due to all bisphenol exposure were deemed insignificant. Considering the accumulating evidence indicating adverse effects at lower exposure levels, further studies are warranted to assess exposure and risk from bisphenol A analogs.

Associations between maternal urinary isoflavone concentrations and anogenital distance of offspring throughout infancy: a prospective cohort study.

Are maternal urinary isoflavone (ISO) concentrations during pregnancy associated with anogenital distance (AGD) in infants at birth, and at 6 and 12 months of age? Higher maternal urinary ISO concentrations during pregnancy were associated with longer AGD in infants of both sexes, and equol (EQU) and daidzein (DAD) were identified as the important ISO mixture components in the observed associations. Evidence of the association of prenatal exposure to ISO with offspring's AGD is mainly derived from animal studies, which used different study designs and had inconsistent results. Only one human study has been reported and it found null associations between maternal ISO exposure during pregnancy and AGD among boys at birth, with a small sample size and a wide range of exposure windows. No human study on girls was found. Prospective cohort study (Shanghai-Minhang Birth Cohort Study), with pregnant women recruited at 12-16 weeks of gestation in Shanghai, China between April and December 2012. One thousand two hundred and twenty-five live singletons were left in the cohort at delivery of which 480 mother-infant pairs had data on both maternal urinary ISO concentrations and at least one AGD measurement and were included in the present study. Anopenile distance (AGDAP) and anoscrotal distance (AGDAS) of boys and anoclitoral distance (AGDAC) and anofourchette distance (AGDAF) of girls were measured at birth and at 6 and 12 months of age. Multiple linear regression models were used to examine the associations between maternal ISO concentrations and AGD. Bayesian kernel machine regression (BKMR) was implemented to examine both the overall effects of ISO mixture and the single effect of each ISO and identify important components of ISO mixture. A general profile of higher concentrations of maternal ISO associated with longer AGD in infants of both sexes was observed, when maternal education, parity, BMI before pregnancy (BMI, categorical variable), passive smoking during early pregnancy, age at delivery, gestational weeks and infant body size were adjusted for. Among boys, EQU was associated with increased AGDAS at birth and at 6 and 12 months, and DAD was associated with increased AGDAP at birth. Among girls, the associations of EQU and DAD with increased AGDAC and AGDAF at birth were found. When gestational weight gain and feeding patterns of infants in the first 6 months were additionally adjusted for, and maternal BMI was adjusted for as a continuous variable, more pronounced associations were observed, especially for associations of genistein (GEN), DAD and glycitein (GLY) with increased AGDAP and AGDAS at 6 months in boys. However, these associations were not always observed in the highest tertile group, and no consistent dose-response relationships were found. Similar results were observed in BKMR models, showing positive correlations of concentration of ISO mixture with increased AGDAS at both 6 and 12 months among boys, and increased AGDAC and AGDAF at birth among girls. Statistically significant increments of 4.96 mm (95% credible interval (CrI): 1.40, 8.52) and 1.07 mm (95% CrI: 0.02, 2.13) in AGDAS at 6 months among boys and AGDAC at birth among girls, respectively, were observed at the 75th percentile of ISO mixture, compared with 25th percentile. EQU and DAD were identified as the important components among ISO-AGD associations. First, due to the short half-lives of ISO, the accuracy of a single spot urine sample reflecting ISO exposure during pregnancy may be limited, and thus may cause non-differential misclassification. Second, despite the adjustments for several important covariates in the study, unmeasured and residual confounding factors may remain a concern. Third, false discovery due to multiple testing may remain. Finally, the reduced sample sizes attributed to the loss of follow-up and missing data of confounders may limit our ability to detect an association, if any existed. Prenatal ISO exposure may affect the reproductive development of offspring. As ISO can be widely detected in pregnant women, especially in Eastern countries, more studies are warranted to provide evidence of the effects of prenatal ISO exposure on long-term reproductive outcomes. This work was supported by grants from the National Key Research and Development Program of China (2021YFC2701003), the National Natural Science Foundation of China (22076123), the Science and Technology Commission of Shanghai Municipality (21ZR1454700 and 20ZR1448000), the Shanghai Municipal Health Commission (20194Y0160) and Innovation-oriented Science and Technology Grant from NHC Key Laboratory of Reproduction Regulation (CX2022-04). The authors have no conflicts of interest to declare. N/A.

Iodine Deficiency in Patients with Hypothyroidism: A Pilot Study.

Objective Worldwide, 21 countries have insufficient iodine in their diets. Persistent iodine deficiency may result in hypothyroidism. The aim of this study is to determine whether iodine measurements can be used to determine the prevalence of iodine deficiency in patients with (subclinical) hypothyroidism compared to a control group. Design A prospective cohort pilot study was performed at the Internal Medicine Outpatient Clinic of Isala, a large teaching hospital in Zwolle, the Netherlands. Patients. This study consisted of two groups of 24 adult patients each: a group of consecutive patients presenting with overt or subclinical hypothyroidism and a control group of euthyroid patients with type 1 diabetes mellitus. Measurements. All patients collected 24-hour urine. Iodine status was determined using urinary iodine concentration (UIC), urinary iodine excretion (UIE), and iodine creatinine ratio (I : Cr). Iodine deficiency was defined as an iodine concentration <100 µg/L for UIC, iodine level <125 µg for UIE, and <0.13 µmol/mmol for I : Cr. Results According to UIE and UIC measurements, 54.2% of hypothyroid patients were iodine-deficient compared to 41.7–45.8% in the control group. According to the I : Cr measurement 91.7% of hypothyroid patients were iodine-deficient compared to 87.5% in the control group. No significant difference was seen between the two groups. No correlation was found between thyroid-stimulating hormone (TSH) level and iodine deficiency. Conclusions Iodine deficiency is prevalent in both hypothyroid patients and euthyroid patients. Because there is no significant difference between the groups, a single 24-hour urine or spot urine sample to determine UIC, UIE, and I : Cr, seems not suitable to determine iodine status in an individual participant.

Urinary phthalate metabolite concentrations and personal care product use during pregnancy – Results of a pilot study

IntroductionPhthalates are reproductive toxicants commonly found in personal care products (PCPs). These endocrine disrupting chemicals are associated with pregnancy complications, including gestational diabetes. Yet, little is known about PCP use as a contributor to urinary phthalate metabolite concentrations in pregnancy. MethodsWe conducted a pilot study among 108 pregnant participants to examine the associations of self-reported PCP use with 14 phthalate and 2 DINCH (di(isononyl) cyclohexane-1,2-dicarboxylate) metabolite concentrations measured in single spot urine samples during pregnancy (median: 36 weeks of gestation). At the time of urine collection, participants self-reported use of hair products (within the last month) and other PCPs (within the last 48 h). We used linear regression to estimate associations for natural log-transformed, specific gravity-corrected concentrations of common PCP-associated phthalate metabolites (monoethyl phthalate [MEP], mono-n-butyl phthalate [MBP], and mono-isobutyl phthalate [MIBP]) in our primary analyses, and additional phthalate metabolites in secondary analyses. ResultsMost urinary metabolites were detected for >90% of participants. Participants who reported using hair oil within the past month had MEP concentrations 125% higher (95% confidence interval [CI]: −0.1, 408) than non-users. For other personal care products, we observed the greatest percent difference in PCP-associated metabolites for MIBP among hair gel users (39.3%, 95% CI: −6.3, 107) and for MEP among conditioner/crème rinse users (−55.4%, 95% CI: −76.4, −15.6) compared to non-users. ConclusionFindings suggest that self-reported use of hair oils during late pregnancy may be associated with higher urinary concentrations of MEP. Hair gel use in late pregnancy may also be associated with higher urinary phthalate metabolite concentrations, while conditioner/crème rinse use may be associated with lower levels if MEP.

Iodine intake in healthy Japanese aged from 6 to 70 years residing in the same district

Iodine is an essential component of thyroid hormones and a dietary micronutrient for humans, and adequate iodine intake is necessary to maintain thyroid function. A population's iodine intake and nutritional status are assessed based on urinary iodine excretion. There are few studies on iodine nutritional status for all age groups residing in the same area in Japan. Between 2010 and 2017, a total of 769 healthy subjects aged 6.4-73 years in three sites in Yokohama City, were enrolled in the survey. The urinary iodine concentration (UIC), iodine to creatinine (Cr) ratio (UI/Cr) and estimated 24-h urinary iodine excretion (UIE) in single spot urine samples were measured, and habitual dietary iodine intake was assessed by food frequency questionnaires. The estimated 24-h UIE was calculated using individual predicted 24-h creatinine excretion by the validated equations developed for healthy Japanese children and adults which vary by age, gender and anthropometry. The median UIC for all participants was 219 μg/L, suggesting adequate iodine intake for this population. There was an increasing trend in median UI/Cr and estimated 24-h UIE by age. A significant correlation between UIC and UI/Cr (r = 0.6378), UIC and estimated 24-h UIE (r = 0.6804), and UI/Cr and estimated 24-h UIE (r = 0.5756) were observed. These estimates can be feasible, convenient and alternative methods to 24-h urine collection in order to assess iodine status in some populations such as ethnically or racially homogeneous and well-nourished people. Additional studies are required to validate these findings.

Associations between arsenic, cadmium, and selenium exposure and oxidative stress in rural residents of northern Laos

BACKGROUND AND AIM: Oxidative stress is an important consequence of exposure to arsenic and cadmium, but it is unclear to what extent low-level exposures contribute to oxidative stress. Additionally, previous studies suggested that selenium suppresses the toxicity of arsenic and cadmium. This study aimed to examine associations between arsenic and cadmium exposure and oxidative damage to DNA and lipid in rural residents of northern Laos, considering selenium interactions with the two toxic elements. METHODS: We collected data on general characteristics (village, sex, age, smoking, drinking, height, and weight) and a single spot urine sample from the participants (n = 341). Urinary concentrations of arsenic, cadmium, and selenium were measured by inductively coupled plasma mass spectrometry to estimate their exposure/intake levels. Urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG) and 8-isoprostane concentrations were measured by liquid chromatography-tandem mass spectrometry (oxidative stress biomarkers of DNA and lipid, respectively). Multiple linear regression analyses examined associations of urinary concentrations of arsenic and cadmium with those of oxidative stress markers, adjusted for covariates. We performed additional analyses to include interaction terms between urinary concentrations of arsenic/cadmium and selenium. RESULTS:Geometric means of specific gravity-adjusted urinary concentrations of arsenic, cadmium, selenium, 8-OHdG, and 8-isoprostane were 40.0, 1.38, 11.7, 3.89, and 0.934 µg/L, respectively. Urinary concentration of arsenic and cadmium showed positive associations with that of 8-isoprostane. We also observed that there were significant interactions between arsenic and selenium in the association with 8-OHdG (Coefficient (95% CI) = -0.21 (-0.37, -0.05)) and between cadmium and selenium in the association with 8-isoprostane (Coefficient (95% CI) = -0.14 (-0.25, -0.03)). CONCLUSIONS:Our findings suggested that arsenic and cadmium exposure were positively associated with oxidative stress in rural residents of northern Laos. Additionally, selenium might have protective effects on arsenic-/cadmium-induced oxidative stress. KEYWORDS: Heavy metals, Chemical exposures, Environmental epidemiology

July 2021 at a glance: focus on blood volume distribution, haemodynamics and adherence to therapy.

July 2021 at a glance: focus on blood volume distribution, haemodynamics and adherence to therapy.

Pre- and early post-natal exposure to phthalates and DINCH in a new type of mother-child cohort relying on within-subject pools of repeated urine samples

For non-persistent chemicals such as phthalates, a single spot urine sample only reflects exposure in the past few hours. Collecting repeated urine samples for each participant over windows of sensitivity is expected to improve exposure characterization but has rarely been done. We aimed to rely on within-subject pools of repeated urine samples to assess phthalate exposure during pregnancy and infancy.Women of the French SEPAGES mother-child cohort were asked to collect three urine samples per day over seven consecutive days, twice during their pregnancy (approximatively second (T2) and third (T3) trimesters). For their infants they also collected one sample per day during a week at two (M2) and twelve months (M12). Samples were pooled (within-subject, within-period) prior to phthalate and DINCH metabolite concentrations assessment. Number of pooled samples assayed was 477, 456, 152 and 100 for T2, T3, M2 and M12, respectively. All metabolites were detected in more than 95% of the pooled samples except for the two DINCH metabolites (oh- and oxo-MINCH), MMCHP and oh-MPHP at M2 for which detection frequencies ranged between 64% and 88%. Maternal concentrations of MiBP, MBzP, DEHP metabolites and oxo-MiNP decreased between 2014 and 2017, whereas concentrations of oh-MiNP and the two DINCH metabolites increased (Mann-Kendall p-values < 0.05). While improved compared to studies that relied on spot samples, Intraclass Correlation Coefficients for the pregnancy were below 0.40 for most metabolites. Spearman correlation coefficients between pooled samples collected in infancy were lower than those observed during pregnancy, and were all below 0.30. Exposure to emerging phthalate substitutes such as DINCH and DPHP seems widespread among pregnant women and infants. Collecting repeated urine samples in pregnant women and infants is feasible. The relatively low correlation across trimesters and between maternal and infant samples highlights the need to collect biospecimens in the assumed sensitive time window.

Salt reduction to prevent hypertension: the reasons of the controversy.

There is a causal relationship between dietary salt intake and blood pressure. A reduction in salt intake from the current world average of ∼10 g/day to the WHO recommended level of <5 g/day, lowers blood pressure and reduces the risk of cardiovascular disease and all-cause mortality. However, a few cohort studies have claimed that there is a J-shaped relationship between salt intake and cardiovascular risk, i.e. both high and low salt intakes are associated with an increased risk. These cohort studies have several methodological problems, including reverse causality, and inaccurate and biased estimation of salt intake, e.g. from a single spot urine sample with formulas. Recent studies have shown that the formulas used to estimate salt intake from spot urine cause a spurious J-curve. Research with inappropriate methodology should not be used to refute the robust evidence on the enormous benefits of population-wide reduction in salt intake. Several countries, e.g. Finland, the UK, have successfully reduced salt intake, which has resulted in falls in population blood pressure and deaths from stroke and ischaemic heart disease. Every country should develop and implement a coherent, workable strategy to reduce salt intake. Even a modest reduction in salt intake across the whole population will lead to a major improvement in public health, along with huge cost-savings to the healthcare service.

Microalbuminuria and its associations with clinical profile and complications of type 2 Diabetes Mellitus

Background and Aims: Microalbuminuria is an early marker of diabetic nephropathy, which accounts for a significant reduction in life expectancy of diabetic patients. Timely detection of microalbuminuria facilitates appropriate preventive and therapeutic approaches to minimize risks. The aim of this study is to determine the prevalence and association of microalbuminuria with clinical profile and complications of type 2 diabetes mellitus.&#x0D; Methods: This study was a descriptive, cross sectional study involving 100 diabetic subjects between July 2018 to January 2019 at Bir Hospital. Microalbuminuria (mg/dl) was defined as spot urine albumin to creatinine ratio of 30-300 mg/g (Kidney Disease Improving Global Outcomes guidelines) in a single spot urine sample. Statistical analysis was done using Statistical package for the social sciences version 20.&#x0D; Results: Microalbuminuria was found in 35% of the sample and the rate was significantly higher among males (P =0.027). Microalbuminuria was significantly related to Body mass index (P = 0.018), duration of diabetes (P =0.000), retinopathy (P = 0.000) and stroke (P = 0.043). No statistically significant relation was found between microalbuminuria and age (P = 0.366), hypertension (P = 0.208), HbA1c (P = 0.098), dyslipidemia (P = 0.171) and ischemic heart disease (P = 0.651).&#x0D; Conclusions: This study shows high prevalence of microalbuminuria in Nepalese Type 2 diabetes mellitus. Screening for microalbuminuria should be done for all the type 2 diabetes mellitus patients for early detection and management of complications of diabetes mellitus.

Non-adherence to heart failure medications predicts clinical outcomes: assessment in a single spot urine sample by liquid chromatography-tandem mass spectrometry (results of a prospective multicentre study).

Liquid chromatography-mass spectrometry (LC-MS/MS) is an objective new technique to assess non-adherence to medications. We used this method to study the prevalence, predictors and outcomes of non-adherence in patients with heart failure with reduced left ventricular ejection fraction (HFrEF). This study included 1296 patients with HFrEF from BIOSTAT-CHF, a study that aimed to optimise guideline-recommended therapies. Angiotensin-converting enzyme inhibitors (ACEi), angiotensin receptor blockers (ARBs), mineralocorticoid receptor antagonists, β-blockers and loop diuretics were measured in a single spot urine sample at 9 months using LC-MS/MS. The relationship between medication non-adherence and the composite endpoint of all-cause death or heart failure hospitalisation, over a median follow-up of 21 months, was evaluated. Non-adherence to at least one prescribed medication was observed in 45.9% of patients. The strongest predictor of non-adherence was non-adherence to any of the other medication classes (P< 0.0005). Regional differences within Europe were observed. On multivariable analyses, non-adherence to ACEi/ARBs and β-blockers was associated with an increased risk of the composite endpoint [hazard ratio (HR) 1.38, 95% confidence interval (CI) 1.09-1.95, P= 0.008 and HR 1.48, 95% CI 1.12-1.96, P= 0.006, respectively). Non-adherence to β-blockers was also associated with an increased risk of death (HR 2.48, 95% CI 1.67-3.68, P< 0.0005). Patients who were non-adherent to loop diuretics were healthier and had a decreased risk of the composite endpoint (HR 0.69, 95% CI 0.51-0.93, P= 0.014). Non-adherence to mineralocorticoid receptor antagonists was not related to any clinical outcome. Non-adherence to medications, assessed by a single urine test, is common and predicts clinical outcomes in patients with HFrEF.

Direct measurement of pregnanediol 3-glucuronide (PDG) in dried urine spots by liquid chromatography-mass spectrometry to detect ovulation

BackgroundNon-invasive self-testing using an objective chemical method to detect ovulation is valuable for women planning conception, practising contraception or undergoing infertility investigations or treatment. MethodsBased on luteal phase secretion of progesterone (P4) and excretion of its major metabolite, pregnanediol glucuronide (PDG), we developed a novel direct liquid chromatography-mass spectrometry (LCMS) method to measure PDG and other steroid glucuronides in urine and in dried urine spots (DUS) without deconjugation or derivatization. Urine PDG by LCMS and immunoassay (P3G) and P4 by immunoassay with and without adjustment for creatinine were evaluated in daily first void urine samples from 10 women through a single menstrual cycle in which ovulation was confirmed by serial transvaginal ultrasound. ResultsUrine PDG with and without creatinine adjustment was stable during the follicular phase with the expected striking rise in the luteal phase peaking at 5 days after ovulation. Using a single spot urine sample (100 μL) or a DUS (<20 μL urine) and an optimal threshold to distinguish pre- from post-ovulatory samples, in ROC analysis urine PDG adjusted for creatinine accurately identified ovulation in 92 % of samples was comparable with P3G immunoassay and superior to urine P4 with or without adjustment for creatinine. Extending the analysis to two or three consecutive daily samples reduced the false negative rate from 8% to 2.6 % for two and 1.9 % for three urine samples. ConclusionsThis method holds promise as a non-invasive self-test method for women to determine by an objective chemical method their ovulatory status.