Estimating mean population salt intake in Fiji and Samoa using spot urine samples

Abstract Background There is an increasing interest in finding less costly and burdensome alternatives to measuring population-level salt intake than 24-h urine collection, such as spot urine samples. However, little is known about their usefulness in developing countries like Fiji and Samoa. The purpose of this study was to evaluate the capacity of spot urine samples to estimate mean population salt intake in Fiji and Samoa. Methods The study involved secondary analyses of urine data from cross-sectional surveys conducted in Fiji and Samoa between 2012 and 2016. Mean salt intake was estimated from spot urine samples using six equations, and compared with the measured salt intake from 24-h urine samples. Differences and agreement between the two methods were examined through paired samples t-test, intraclass correlation coefficient analysis, and Bland-Altman plots and analyses. Results A total of 414 participants from Fiji and 725 participants from Samoa were included. Unweighted mean salt intake based on 24-h urine collection was 10.58 g/day (95% CI 9.95 to 11.22) in Fiji and 7.09 g/day (95% CI 6.83 to 7.36) in Samoa. In both samples, the INTERSALT equation with potassium produced the closest salt intake estimate to the 24-h urine (difference of − 0.92 g/day, 95% CI − 1.67 to − 0.18 in the Fiji sample and + 1.53 g/day, 95% CI 1.28 to 1.77 in the Samoa sample). The presence of proportional bias was evident for all equations except for the Kawasaki equation. Conclusion These data suggest that additional studies where both 24-h urine and spot urine samples are collected are needed to further assess whether methods based on spot urine samples can be confidently used to estimate mean population salt intake in Fiji and Samoa.

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Mean Dietary Salt Intake in Vanuatu: A Population Survey of 755 Participants on Efate Island

Nutrients ◽

10.3390/nu11040916 ◽

2019 ◽

Vol 11 (4) ◽

pp. 916

Author(s):

Katherine Paterson ◽

Nerida Hinge ◽

Emalie Sparks ◽

Kathy Trieu ◽

Joseph Alvin Santos ◽

...

Keyword(s):

Salt Intake ◽

Urine Samples ◽

World Health ◽

Dietary Salt ◽

Cross Sectional Survey ◽

Cross Sectional ◽

Middle Income ◽

Dietary Salt Intake ◽

Spot Urine ◽

Salt Consumption

Non-communicable diseases are responsible for 63% of global deaths, with a higher burden in low- and middle-income countries. Hypertension is the leading cause of cardiovascular-disease-related deaths worldwide, and approximately 1.7 million deaths are directly attributable to excess salt intake annually. There has been little research conducted on the level of salt consumption amongst the population of Vanuatu. Based on data from other Pacific Island countries and knowledge of changing regional diets, it was predicted that salt intake would exceed the World Health Organization’s (WHO) recommended maximum of 5 g per day. The current study aimed to provide Vanuatu with a preliminary baseline assessment of population salt intake on Efate Island. A cross-sectional survey collected demographic, clinical, and urine data from participants aged 18 to 69 years in rural and urban communities on Efate Island in October 2016 and February 2017. Mean salt intake was determined to be 7.2 (SD 2.3) g/day from spot urine samples, and 5.9 (SD 3.6) g/day from 24-h urine samples, both of which exceed the WHO recommended maximum. Based on the spot urine samples, males had significantly higher salt intake than females (7.8 g compared to 6.5 g; p < 0.001) and almost 85% of the population consumed more than the WHO recommended maximum daily amount. A coordinated government strategy is recommended to reduce salt consumption, including fiscal policies, engagement with the food industry, and education and awareness-raising to promote behavior change.

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Estimating sodium intake from spot urine samples at population level: a validation and application study in French adults

British Journal Of Nutrition ◽

10.1017/s0007114519000886 ◽

2019 ◽

Vol 122 (2) ◽

pp. 186-194 ◽

Cited By ~ 1

Author(s):

Elise Emeville ◽

Camille Lassale ◽

Katia Castetbon ◽

Valérie Deschamps ◽

Benoît Salanave ◽

...

Keyword(s):

Salt Intake ◽

Sodium Intake ◽

Adult Population ◽

Correlation Coefficients ◽

Population Level ◽

Urine Samples ◽

Validation Sample ◽

Application Study ◽

Spot Urine ◽

Calibration Coefficients

AbstractThe aim of this study was to assess the validity of the predictive INTERSALT equation using spot urine samples to estimate 24-h urinary Na (24-hUNa) excretion and daily Na intake among the French adult population. Among 193 French adults (‘validation sample’), we assessed the validity by comparing predicted 24-hUNa excretion from spot urine and measured 24-hUNa excretion from 24-h urine collections. Spearman correlation coefficients and Bland–Altman plots were used and we calculated calibration coefficients. In a nationally representative sample of 1720 French adults (‘application sample’), the calibrated predictive equation was then applied to the spot urine Na values to estimate 24-hUNa excretion and daily Na intake. In that sample, predicted Na intake was compared with that estimated from 24-h dietary recalls. Results were adjusted and corrected using calibration coefficients. In the validation sample, the measured 24-hUNa excretion was on average 14 % higher than the predicted 24-hUNa (+13 % for men and +16 % for women). Correlation between measured and predicted 24-hUNa excretion was moderate (Spearman r 0·42), and the Bland–Altman plots showed underestimation at lower excretion level and overestimation at higher level. In the application study, estimated daily salt intake was 8·0 g/d using dietary recalls, 8·1 g/d using predicted INTERSALT equation and 9·3 g/d after applying calibration coefficients calculated in the validation study. Despite overall underestimation of 24-hUNa excretion by spot urinary Na, the use of predictive INTERSALT equation remains an acceptable alternative in monitoring global Na intake/excreted in the French population but its use is not advised at the individual level.

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Perbandingan kandungan iodium dalam urin antara sampel urin 24 jam dan on spot pada anak usia sekolah

Jurnal Gizi Klinik Indonesia ◽

10.22146/ijcn.17865 ◽

2017 ◽

Vol 13 (3) ◽

pp. 129

Author(s):

Widya Ayu Kurnia Putri ◽

Dodik Briawan ◽

Hidayat Syarif ◽

Leily Amelia

Keyword(s):

Iodine Concentration ◽

Cross Sectional Study ◽

Urine Samples ◽

School Age Children ◽

Healthy Children ◽

Urine Collection ◽

Cross Sectional ◽

Iodine Status ◽

Spot Urine ◽

Epidemiological Surveys

Background: Urine Iodine Concentration (UIC) is the indicator to assess iodine status. UIC from 24-hour urine collection appropriate to used as a direct measure of the iodine status and helps to validate the estimates intake of iodine. 24-hours urine collection is not practical in large studies and epidemiological surveys because it is quite difficult to complete and accurate collection. WHO/UNICEF/ICCIDD recommend the use of on spot urine collection.Objective: The aim of this study was to compare of 24-hour urine collection and spot urine collection for the assessment UIC in children.Method: The cross-sectional study was applied in Bogor. UIC was measured in 24-hour urine and parallel collected three spot urine namely on spot 1 collected morning, on spot 2 collected afternoon, and on spot 3 collected evening, sample urine collected from 44 healthy children age 10-13 years. UIC of 24-hour urine and one spot urine analyzed in the laboratory GAKY FK UNDIP using acid digestion method.Results: The average UIC from 24-hour urine collection was 179.77 ± 56.4 µg/l and UIC from on spot urine collection were on spot morning 145.30 ± 63.6 µg/l, on spot afternoon 159.95 ± 64.5 µg/l, and on spot evening 167.50 ± 66.1 µg/l. However, UIC correlation between UIC from on spot afternoon and UIC 24-hour (r = 0.456) with 66.67 % sensitivity and 75.61 % specificity.Conclusion: UIC urine samples from lunch to dinner more accurately reflects the UIC 24 hours to categorize the iodine status of the population. UIC from spot urine samples collected on the afternoon can be used as an alternative to evaluate the iodine status of school-age children.

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Development, validation and application of a machine learning model to estimate salt consumption in 54 countries

eLife ◽

10.7554/elife.72930 ◽

2022 ◽

Vol 11 ◽

Author(s):

Wilmer Cristobal Guzman-Vilca ◽

Manuel Castillo-Cara ◽

Rodrigo M Carrillo-Larco

Keyword(s):

Machine Learning ◽

Salt Intake ◽

Population Level ◽

American Samoa ◽

Population Based ◽

Urine Samples ◽

Spot Urine ◽

Salt Consumption ◽

Model Based ◽

Machine Learning Model

Global targets to reduce salt intake have been proposed but their monitoring is challenged by the lack of population-based data on salt consumption. We developed a machine learning (ML) model to predict salt consumption at the population level based on simple predictors and applied this model to national surveys in 54 countries. We used 21 surveys with spot urine samples for the ML model derivation and validation; we developed a supervised ML regression model based on: sex, age, weight, height, systolic and diastolic blood pressure. We applied the ML model to 54 new surveys to quantify the mean salt consumption in the population. The pooled dataset in which we developed the ML model included 49,776 people. Overall, there were no substantial differences between the observed and ML-predicted mean salt intake (p<0.001). The pooled dataset where we applied the ML model included 166,677 people; the predicted mean salt consumption ranged from 6.8 g/day (95% CI: 6.8-6.8 g/day) in Eritrea to 10.0 g/day (95% CI: 9.9-10.0 g/day) in American Samoa. The countries with the highest predicted mean salt intake were in Western Pacific. The lowest predicted intake was found in Africa. The country-specific predicted mean salt intake was within reasonable difference from the best available evidence. A ML model based on readily available predictors estimated daily salt consumption with good accuracy. This model could be used to predict mean salt consumption in the general population where urine samples are not available.

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Can methods based on spot urine samples be used to estimate average population 24 h sodium excretion? Results from the Isfahan Salt Study

Public Health Nutrition ◽

10.1017/s136898001900257x ◽

2019 ◽

Vol 23 (2) ◽

pp. 202-213 ◽

Cited By ~ 1

Author(s):

Noushin Mohammadifard ◽

Hamidreza Marateb ◽

Marjan Mansourian ◽

Alireza Khosravi ◽

Zahra Abdollahi ◽

...

Keyword(s):

Healthy Volunteer ◽

Validation Study ◽

Salt Intake ◽

Population Characteristics ◽

Urine Samples ◽

Urine Collection ◽

Group Level ◽

Spot Urine ◽

Larger Sample ◽

Urine Specimens

AbstractObjective:To assess agreement between established methods of estimating salt intake from spot urine collections and 24 h urinary Na (24hUNa) and then to develop a valid formula that can be used in the Iranian population to estimate salt intake from spot urine samples.Design:A validation study. Three spot urine samples were collected (fasting second-void morning; afternoon; evening) on the same day as a 24 h urine collection. We estimated 24hUNa from spot specimens using the Kawasaki, Tanaka and INTERSALT equations. Two new formulas were developed, the Iran formula 1 (Iran 1) and Iran formula 2 (Iran 2), based on our population characteristics.Setting:Iranian adults recruited in 2014–2015.Participants:Healthy volunteer adults aged ≥18 years.Results:With all three spot urine specimens, predicted population 24hUNa was underestimated based on the INTERSALT equation (−469 to −708 mg/d; all P < 0·05) and conversely overestimation occurred with the Kawasaki equation (926 to 1080 mg/d; all P < 0·01). The Tanaka equation produced comparable estimates to measured 24hUNa (–151 to 86 mg/d; all P > 0·49). The newly derived formulas, Iran 1 and Iran 2, showed less mean bias than the established equations (Iran 1: 43 to 80 mg/d, all P > 0·55; Iran 2: 22 to 90 mg/d, all P > 0·50).Conclusions:In this Iranian sample, the Tanaka equation and newly derived formulas produced group-level estimates comparable to measured 24hUNa. The newly developed formulas showed less mean bias than established equations; however, they need to be tested for generalization in a larger sample.

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Validity of predictive equations for 24-h urinary potassium excretion based on timing of spot urine collection among adults: the MESA and CARDIA Urinary Sodium Study and NHANES Urinary Sodium Calibration Study

American Journal of Clinical Nutrition ◽

10.1093/ajcn/nqy138 ◽

2018 ◽

Vol 108 (3) ◽

pp. 532-547 ◽

Cited By ~ 8

Author(s):

Carla I Mercado ◽

Mary E Cogswell ◽

Catherine M Loria ◽

Kiang Liu ◽

Norrina Allen ◽

...

Keyword(s):

Prediction Equation ◽

Cross Sectional Study ◽

Urinary Sodium ◽

Urine Samples ◽

Potassium Excretion ◽

Urine Collection ◽

Cross Sectional ◽

Spot Urine ◽

Study Results ◽

Urinary Potassium

ABSTRACT Background 24-h urine collections are the suggested method to measure daily urinary potassium excretion (uK) but are costly and burdensome to implement. Objective This study tested how well existing equations with the use of spot urine samples can estimate 24-h uK and if accuracy varies by timing of spot urine collection, age, race, or sex. Design This cross-sectional study used data from 407 participants aged 18–39 y from the Washington, DC area in 2011 and 554 participants aged 45–79 y from Chicago in 2013. Spot urine samples were collected in individual containers for 24 h, and 1 for each timed period (morning, afternoon, evening, and overnight) was selected. For each selected timed spot urine, 24-h uK was predicted through the use of published equations. Difference (bias) between predicted and measured 24-h uK was calculated for each timed period and within age, race, and sex subgroups. Individual-level differences were assessed through the use of Bland-Altman plots and correlation tests. Results For all equations, regardless of the timing of spot urine, mean bias was usually significantly different than 0. No one prediction equation was unbiased across all sex, race, and age subgroups. With the use of the Kawasaki and Tanaka equations, 24-h uK was overestimated at low levels and underestimated at high levels, whereas observed differential bias with the Mage equation was in the opposite direction. Depending on prediction equation and timing of urine sample, 61–75% of individual 24-h uKs were misclassified among 500-mg incremental categories from <1500 to ≥3000 mg. Correlations between predicted and measured 24-h uK were poor to moderate (0.19–0.71). Conclusion Because predicted 24-h uK accuracy varies by timing of spot urine collection, published prediction equations, and within age-race-sex subgroups, study results making use of predicted 24-h uK in association with health outcomes should be interpreted with caution. It is possible that a more accurate prediction equation can be developed leading to different results.

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Biochemical Assessment of Renal and Liver Function among Preeclamptics in Lagos Metropolis

International Journal of Reproductive Medicine ◽

10.1155/2018/1594182 ◽

2018 ◽

Vol 2018 ◽

pp. 1-6

Author(s):

Oloruntoba Ayodele Ekun ◽

Oluwatumininu Mary Olawumi ◽

Christian Chigozie Makwe ◽

Nkeiruka Ogochukwu Ogidi

Keyword(s):

Uric Acid ◽

Liver Function ◽

Total Protein ◽

Venous Blood ◽

Urine Samples ◽

Plasma Sodium ◽

Cross Sectional ◽

Blood Samples ◽

Spot Urine ◽

Specific Syndrome

Objectives. Preeclampsia is a pregnancy specific syndrome. Studies have shown that preeclampsia has multiorgan dysfunction effects. This study evaluated biomarkers of renal and liver function among preeclamptic Nigerian women. Study Design. This was a cross-sectional study conducted among 49 preeclamptic women and 50 normotensive healthy pregnant women. Method. The baseline data comprising age, gestational age, and blood pressure were obtained. Venous blood and spot urine samples were collected from each participant. Plasma obtained from blood samples taken into lithium heparinized vacutainer bottles was assayed for electrolytes, urea, creatinine, total protein, albumin, and uric acid, while sera samples from blood samples taken into serum separation tube- (SST-) gel vacutainer were assayed for aspartate transaminase and alanine transaminase using ion selective electrode technique and Cobas autoanalyzer. Spot urine samples were assayed for protein and creatinine using Pyrogallol’s reagent and Jaffe’s methods, respectively. Microalbuminuria (protein/creatinine ratio) was generated from spot urine protein and creatinine data. Result. The plasma sodium, total protein, and albumin in preeclamptic group were significantly decreased (p<0.05) when compared with control. There was statistically significant increase (p<0.05) in microalbuminuria, plasma potassium, urea, creatinine, uric acid levels, serum AST, and ALT activities in preeclamptic group. A positive association (p<0.05) between alanine aminotransferase and biomarkers of renal function was observed. Conclusion. Preeclampsia has deleterious effects on renal and liver function as shown by alteration of these parameters.

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Abstract P262: Spot Urine Sodium to Potassium Ratio Predicts Increasing Blood Pressure Levels in a General Population: The Nagahama Study

Hypertension ◽

10.1161/hyp.68.suppl_1.p262 ◽

2016 ◽

Vol 68 (suppl_1) ◽

Author(s):

Yasuharu Tabara ◽

Yoshimitsu Takahashi ◽

Takeo Nakayama ◽

Fumihiko Matsuda

Keyword(s):

Blood Pressure ◽

Salt Intake ◽

Linear Regression Analysis ◽

Prognostic Significance ◽

Reverse Causality ◽

Cross Sectional ◽

Salt Loading ◽

Available N ◽

Spot Urine

Excessive salt intake is a risk factor for hypertension. The most reliable method for estimating daily salt intake is measurement of 24-h urinary sodium excretion, while it is inconvenient. Sodium-to-potassium ratio (Na/K) of a urine sample is another index of salt loading. We previously reported that a simple measure of spot urine Na/K might be a representative of salt loading in a cross-sectional setting. Here, we conducted a longitudinal study aiming to clarify a prognostic significance of spot urine Na/K for increasing blood pressure (BP) levels. Study subjects consists of 9,769 general individuals. Among them, individuals whose baseline Na/K was available (n=9,328), who were normotensive at baseline (n=6,392), and who participated in the follow-up measurement (n=5,209) were included in this analysis (51.8±12.9 years old, male: 29.2%). Mean follow-up duration was 5.0±0.5 years. Mean Na/K at baseline was 3.1±1.7, and showed step-wise increase with BP levels (optimal: 3.0±1.6, normal: 3.3±1.8, high normal: 3.4±1.8, P<0.001). Other major factors that were significantly associated with Na/K was fasting time (r=-0.220, P<0.001), and CKD (CKD (n=694): 2.7±1.6, control: 3.2±1.7, P<0.001). Mean SBP was significantly increased during follow-up period (baseline: 116±12, follow-up: 119±15 mmHg), and 805 individuals (15.5%) were newly diagnosed as hypertension (HT). These individuals were significantly older (HT: 60.3±9.9, NT: 50.3±12.8 years), were frequently male (36.4%, 27.9%), and had higher SBP (127±9, 115±11 mmHg) at baseline (P<0.001). In contrast, baseline spot urine Na/K was slightly lower in individuals who developed HT (3.0±1.6, 3.1±1.8, P=0.013), while that measured at follow-up investigation was oppositely higher in hypertensives (3.1±1.8, 2.8±1.5, P<0.001). Multiple linear regression analysis adjusted for the covariates identified baseline Na/K (β=0.108, P<0.001) and changes in Na/K during follow-up period (β=0.222, P<0.001) as independent determinants for future SBP levels. Higher spot urine Na/K, as well as increases in the Na/K levels, was significant determinant for future BP levels. The apparently lower baseline Na/K levels in individuals who developed HT might be due to reverse causality.

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

Journal of Nutrition ◽

10.1093/jn/nxy211 ◽

2018 ◽

Vol 148 (12) ◽

pp. 1946-1953 ◽

Cited By ~ 6

Author(s):

Magali Rios-Leyvraz ◽

Pascal Bovet ◽

René Tabin ◽

Bernard Genin ◽

Michel Russo ◽

...

Keyword(s):

Sodium Excretion ◽

Salt Intake ◽

Sodium Intake ◽

Population Level ◽

Urinary Sodium Excretion ◽

Cross Sectional Study ◽

Urinary Sodium ◽

Cross Sectional ◽

High Sodium ◽

Individual Level

ABSTRACT Background 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. Objective 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. Methods 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. Results 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. Conclusions 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.

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