Urine Spot Samples Can Be Used to Estimate 24-Hour Urinary Sodium Excretion in Children.

The gold standard to assess salt intake is 24-h urine collections. Use of a urine spot sample can be a simpler alternative, especially when the goal is to assess sodium intake at the population level. Several equations to estimate 24-h urinary sodium excretion from urine spot samples have been tested in adults, but not in children. The objective of this study was to assess the ability of several equations and urine spot samples to estimate 24-h urinary sodium excretion in children. A cross-sectional study of children between 6 and 16 y of age was conducted. Each child collected one 24-h urine sample and 3 timed urine spot samples, i.e., evening (last void before going to bed), overnight (first void in the morning), and morning (second void in the morning). Eight equations (i.e., Kawasaki, Tanaka, Remer, Mage, Brown with and without potassium, Toft, and Meng) were used to estimate 24-h urinary sodium excretion. The estimates from the different spot samples and equations were compared with the measured excretion through the use of several statistics. Among the 101 children recruited, 86 had a complete 24-h urine collection and were included in the analysis (mean age: 10.5 y). The mean measured 24-h urinary sodium excretion was 2.5 g (range: 0.8-6.4 g). The different spot samples and equations provided highly heterogeneous estimates of the 24-h urinary sodium excretion. The overnight spot samples with the Tanaka and Brown equations provided the most accurate estimates (mean bias: -0.20 to -0.12 g; correlation: 0.48-0.53; precision: 69.7-76.5%; sensitivity: 76.9-81.6%; specificity: 66.7%; and misclassification: 23.0-27.7%). The other equations, irrespective of the timing of the spot, provided less accurate estimates. Urine spot samples, with selected equations, might provide accurate estimates of the 24-h sodium excretion in children at a population level. At an individual level, they could be used to identify children with high sodium excretion. This study was registered at clinicaltrials.gov as NCT02900261

Risk factors during first 1,000 days of life for carotid intima-media thickness in infants, children, and adolescents: A systematic review with meta-analyses.

The first 1,000 days of life, i.e., from conception to age 2 years, could be a critical period for cardiovascular health. Increased carotid intima-media thickness (CIMT) is a surrogate marker of atherosclerosis. We performed a systematic review with meta-analyses to assess (1) the relationship between exposures or interventions in the first 1,000 days of life and CIMT in infants, children, and adolescents; and (2) the CIMT measurement methods. Systematic searches of Medical Literature Analysis and Retrieval System Online (MEDLINE), Excerpta Medica database (EMBASE), and Cochrane Central Register of Controlled Trials (CENTRAL) were performed from inception to March 2019. Observational and interventional studies evaluating factors at the individual, familial, or environmental levels, for instance, size at birth, gestational age, breastfeeding, mode of conception, gestational diabetes, or smoking, were included. Quality was evaluated based on study methodological validity (adjusted Newcastle-Ottawa Scale if observational; Cochrane collaboration risk of bias tool if interventional) and CIMT measurement reliability. Estimates from bivariate or partial associations that were least adjusted for sex were used for pooling data across studies, when appropriate, using random-effects meta-analyses. The research protocol was published and registered on the International Prospective Register of Systematic Reviews (PROSPERO; CRD42017075169). Of 6,221 reports screened, 50 full-text articles from 36 studies (34 observational, 2 interventional) totaling 7,977 participants (0 to 18 years at CIMT assessment) were retained. Children born small for gestational age had increased CIMT (16 studies, 2,570 participants, pooled standardized mean difference (SMD): 0.40 (95% confidence interval (CI): 0.15 to 0.64, p: 0.001), I2: 83%). When restricted to studies of higher quality of CIMT measurement, this relationship was stronger (3 studies, 461 participants, pooled SMD: 0.64 (95% CI: 0.09 to 1.19, p: 0.024), I2: 86%). Only 1 study evaluating small size for gestational age was rated as high quality for all methodological domains. Children conceived through assisted reproductive technologies (ART) (3 studies, 323 participants, pooled SMD: 0.78 (95% CI: -0.20 to 1.75, p: 0.120), I2: 94%) or exposed to maternal smoking during pregnancy (3 studies, 909 participants, pooled SMD: 0.12 (95% CI: -0.06 to 0.30, p: 0.205), I2: 0%) had increased CIMT, but the imprecision around the estimates was high. None of the studies evaluating these 2 factors was rated as high quality for all methodological domains. Two studies evaluating the effect of nutritional interventions starting at birth did not show an effect on CIMT. Only 12 (33%) studies were at higher quality across all domains of CIMT reliability. The degree of confidence in results is limited by the low number of high-quality studies, the relatively small sample sizes, and the high between-study heterogeneity. In our meta-analyses, we found several risk factors in the first 1,000 days of life that may be associated with increased CIMT during childhood. Small size for gestational age had the most consistent relationship with increased CIMT. The associations with conception through ART or with smoking during pregnancy were not statistically significant, with a high imprecision around the estimates. Due to the large uncertainty in effect sizes and the limited quality of CIMT measurements, further high-quality studies are needed to justify intervention for primordial prevention of cardiovascular disease (CVD)

Sodium intake and blood pressure in children with clinical conditions: A systematic review with meta-analysis.

Little is known on the effect of sodium intake on BP of children with clinical conditions. Our objective was therefore to review systematically studies that have assessed the association between sodium intake and BP in children with various clinical conditions. A systematic search of several databases was conducted and supplemented by a manual search of bibliographies and unpublished studies. Experimental and observational studies assessing the association between sodium intake and BP and involving children or adolescents between 0 and 18 years of age with any clinical condition were included. Out of the 6861 records identified, 51 full texts were reviewed, and 16 studies (10 experimental and 6 observational), involving overall 2902 children and adolescents, were included. Ten studies were conducted in children with elevated BP without identifiable cause, two in children with familial hypertension, one in children with at least one cardiovascular risk factor, one in children with chronic renal insufficiency, one in children with urolithiasis, and one in premature infants. A positive association between sodium intake and BP was found in all studies, except one. The meta-analysis of six studies among children with elevated BP without identifiable cause revealed a difference of 6.3 mm Hg (95% CI 2.9-9.6) and 3.5 mm Hg (95% CI 1.2-5.7) in systolic and diastolic BP, respectively, for every additional gram of sodium intake per day. In conclusion, our results indicate that the BP response to salt is greater in children with clinical conditions, mainly hypertension, than in those without associated clinical conditions

Population biomonitoring of micronutrient intakes in children using urinary spot samples.

Urinary spot samples are a promising method for the biomonitoring of micronutrient intake in children. Our aim was to assess whether urinary spot samples could be used to estimate the 24-h urinary excretion of potassium, phosphate, and iodine at the population level. A cross-sectional study of 101 children between 6 and 16 years of age was conducted. Each child collected a 24-h urine collection and three urinary spot samples (evening, overnight, and morning). Several equations were used to estimate 24-h excretion based on the urinary concentrations of each micronutrient in the three spot samples. Various equations and spot combinations were compared using several statistics and plots. Ninety-four children were included in the analysis (mean age: 10.5 years). The mean measured 24-h urinary excretions of potassium, phosphate, and iodine were 1.76 g, 0.61 g, and 95 µg, respectively. For potassium, the best 24-h estimates were obtained with the Mage equation and morning spot (mean bias: 0.2 g, correlation: 0.27, precision: 56%, and misclassification: 10%). For phosphate, the best 24-h estimates were obtained with the Mage equation and overnight spot (mean bias: - 0.03 g, correlation: 0.54, precision: 72%, and misclassification: 10%). For iodine, the best 24-h estimates were obtained with the Remer equation and overnight spot (mean bias: - 8 µg, correlation: 0.58, precision: 86%, misclassification: 16%). Urinary spot samples could be a good alternative to 24-h urine collection for the population biomonitoring of iodine and phosphate intakes in children. For potassium, spot samples were less reliable

Monitoring caffeine intake in children with a questionnaire and urine collection: a cross-sectional study in a convenience sample in Switzerland.

The objectives of this study were (1) to estimate caffeine intake and identify the main sources of intake using a dietary questionnaire, (2) to assess 24-h urinary excretion of caffeine and its metabolites, and (3) to assess how self-reported intake estimates correlates with urinary excretion among children in Switzerland. We conducted a cross-sectional study of children between 6 and 16 years of age in one region of Switzerland. The participants filled in a dietary questionnaire and collected a 24-h urine sample. Caffeine intake was estimated with the questionnaire. Caffeine, paraxanthine, theophylline, and theobromine excretions were measured in the urine sample. Correlations between questionnaire-based intake and urinary excretion estimates were assessed using Spearman correlation coefficients. Ninety-one children were included in the analysis (mean age 10.6 years; 43% female). The mean daily caffeine intake estimate derived from the diet questionnaire was 39 mg (range 0-237), corresponding, when related to body weight, to 1.2 mg/kg (range 0.0-6.3). Seven children (8%) had a caffeine intake above the upper recommended level of 3 mg/kg per day. The main sources of caffeine intake were cocoa milk (29%), chocolate (25%), soft drinks (11%), mocha yogurt (10%), tea (8%), and energy drinks (8%). The 24-h urinary excretion of caffeine was 0.3 mg (range 0.0-1.5), paraxanthine 1.4 mg (range 0.0-7.1), theophylline 0.1 mg (range 0.0-0.6), and theobromine 14.8 mg (range 0.3-59.9). The correlations between estimates of caffeine intake and the 24-h urinary excretion of caffeine was modest (ρ = 0.21, p = 0.046) and with the metabolites of caffeine were weak (ρ = 0.09-0.11, p = 0.288-0.423). Caffeine intake in a sample of children in a region of Switzerland was relatively low. The major sources of intake were cocoa milk, chocolate and soft drinks. Self-reported caffeine intake correlated weakly with urinary excretion of caffeine and some of its main metabolites. NCT02900261

Spot urine samples to estimate 24-hour urinary calcium excretion in school-age children.

Urinary calcium/creatinine ratio (UCa/Cr) on a single spot urine sample is frequently used in children to evaluate calciuria, but its accuracy to estimate 24-h urinary calcium excretion (24hUCa) has not been properly assessed. We analyzed the correlation between UCa/Cr in various spot samples and 24hUCa among healthy children. A 24-h urine specimen and three spot urine samples (evening, first, and second morning) were collected in a convenience sample of children aged 6 to 16 years (n = 101). Measured 24hUCa was compared with UCa/Cr in each of the three spot samples. The ability of UCa/Cr to discriminate between children with and without hypercalciuria (calciuria > 4 mg/kg/24 h, 1 mmol/kg/24 h) and optimal timing of the spot sample were determined. Eighty-five children completed an adequate 24-h urine collection. Pearson correlation coefficients between the UCa/Cr on the spot sample and 24hUCa were 0.64, 0.71, and 0.52 for the evening, first, and second morning spot samples, respectively. Areas under the ROC curve were 0.90, 0.82, and 0.75, respectively, for the corresponding spot samples.Conclusion: The relatively strong correlation between 24hUCa and UCa/Cr in evening and first morning spot urine samples suggests that these spots could be preferred in clinical practice.Trial registration: ClinicalTrials.gov , NCT02900261, date of trial registration 14 September 2016. What is Known: •Urinary calcium/creatinine ratio on a single spot urine sample is frequently used as a proxy for 24-h urinary calcium excretion. •Correlation of these indicators, including the best timing for spot urine sampling, has not been properly assessed. What is New: •Relatively strong correlations were found between the calcium/creatinine ratio on a single spot urine sample and 24-h urinary calcium excretion in healthy children. •Evening and first morning spot samples had the highest correlation