Xiangxian Feng

School based education programme to reduce salt intake in children and their families (School-EduSalt): cluster randomised controlled trial

Objective To determine whether an education programme targeted at schoolchildren could lower salt intake in children and their families. Design Cluster randomised controlled trial, with schools randomly assigned to either the intervention or control group. Setting 28 primary schools in urban Changzhi, northern China. Participants 279 children in grade 5 of primary school, with mean age of 10.1; 553 adult family members (mean age 43.8). Intervention Children in the intervention group were educated on the harmful effects of salt and how to reduce salt intake within the schools’ usual health education lessons. Children then delivered the salt reduction message to their families. The intervention lasted for one school term (about 3.5 months). Main outcome measures The primary outcome was the difference between the groups in the change in salt intake (as measured by 24 hour urinary sodium excretion) from baseline to the end of the trial. The secondary outcome was the difference between the two groups in the change in blood pressure. Results At baseline, the mean salt intake in children was 7.3 (SE 0.3) g/day in the intervention group and 6.8 (SE 0.3) g/day in the control group. In adult family members the salt intakes were 12.6 (SE 0.4) and 11.3 (SE 0.4) g/day, respectively. During the study there was a reduction in salt intake in the intervention group, whereas in the control group salt intake increased. The mean effect on salt intake for intervention versus control group was −1.9 g/day (95% confidence interval −2.6 to −1.3 g/day; P<0.001) in children and −2.9 g/day (−3.7 to −2.2 g/day; P<0.001) in adults. The mean effect on systolic blood pressure was −0.8 mm Hg (−3.0 to 1.5 mm Hg; P=0.51) in children and −2.3 mm Hg (−4.5 to −0.04 mm Hg; P<0.05) in adults. Conclusions An education programme delivered to primary school children as part of the usual curriculum is effective in lowering salt intake in children and their families. This offers a novel and important approach to reducing salt intake in a population in which most of the salt in the diet is added by consumers. Trial registration ClinicalTrials.gov NCT01821144. 

A large-scale cluster randomized trial to determine the effects of community-based dietary sodium reduction-the China Rural Health Initiative Sodium Reduction Study

BACKGROUND Cardiovascular diseases are the leading cause of death and disability in China. High blood pressure caused by excess intake of dietary sodium is widespread and an effective sodium reduction program has potential to improve cardiovascular health. DESIGN This study is a large-scale, cluster-randomized, trial done in five Northern Chinese provinces. Two counties have been selected from each province and 12 townships in each county making a total of 120 clusters. Within each township one village has been selected for participation with 1:1 randomization stratified by county. The sodium reduction intervention comprises community health education and a food supply strategy based upon providing access to salt substitute. Subsidization of the price of salt substitute was done in 30 intervention villages selected at random. Control villages continued usual practices. The primary outcome for the study is dietary sodium intake level estimated from assays of 24-hour urine. TRIAL STATUS The trial recruited and randomized 120 townships in April 2011. The sodium reduction program was commenced in the 60 intervention villages between May and June of that year with outcome surveys scheduled for October to December 2012. Baseline data collection shows that randomisation achieved good balance across groups. DISCUSSION The establishment of the China Rural Health Initiative has enabled the launch of this large-scale trial designed to identify a novel, scalable strategy for reduction of dietary sodium and control of blood pressure. If proved effective, the intervention could plausibly be implemented at low cost in large parts of China and other countries worldwide.

A school-based education programme to reduce salt intake in children and their families (School-EduSalt): protocol of a cluster randomised controlled trial

Introduction The current salt intake is very high for children as well as adults in China. A reduction in salt intake is one of the most cost-effective measures to curb the rapidly growing disease burden attributed to blood pressure and cardiovascular disease in the Chinese population. A lower salt diet starting from childhood has the potential to prevent the development of such conditions. The School-EduSalt (School-based Education Programme to Reduce Salt) study aims to determine whether an education programme targeted at school children can lower salt intake in children and their families. Methods and analysis The study is designed as a cluster randomised controlled trial. The location is Changzhi, Shanxi province in northern China. The study population will consist of 28 primary schools with 280 children aged ≈11 years and 560 adult family members. Children in the intervention group will be educated on how to reduce salt intake. They will then be empowered to deliver the salt reduction message home to their families. In particular, children need to persuade the person who does the cooking to reduce the amount of salt used during food preparations. The duration of the intervention is one school term (≈4.5 months). The primary outcome is the difference between the intervention and the control group in the change in 24 h urinary sodium and the secondary outcome is the difference between the intervention and control group in the change of blood pressure. An economic evaluation will be undertaken to assess cost-effectiveness. Ethics and dissemination The study has been approved by The Queen Mary Research Ethics Committee (QMREC2012/81) and Peking University Health Science Centre IRB (IRB00001052-12072). Study findings will be disseminated widely through conference presentations and peer-reviewed publications. Protocol Registration Protocol Registered on ClinicalTrials.gov NCT01821144.

The Effects of a Community-Based Sodium Reduction Program in Rural China – A Cluster-Randomized Trial

Background Average sodium intake and stroke mortality in northern China are both among the highest in the world. An effective, low-cost strategy to reduce sodium intake in this population is urgently needed. Objective We sought to determine the effects of a community-based sodium reduction program on salt consumption in rural northern China. Design This study was a cluster-randomized trial done over 18 months in 120 townships (one village from each township) from five provinces. Sixty control villages were compared to 60 intervention villages that were given access to a reduced-sodium, added-potassium salt substitute in conjunction with a community-based health education program focusing on sodium reduction. The primary outcome was the difference in 24-hour urinary sodium excretion between randomized groups. Results Among 1,903 people with valid 24-hour urine collections, mean urinary sodium excretion in intervention compared with control villages was reduced by 5.5% (-14mmol/day, 95% confidence interval -26 to -1; p = 0.03), potassium excretion was increased by 16% (+7mmol/day, +4 to +10; p<0.001), and sodium to potassium ratio declined by 15% (-0.9, -1.2 to -0.5; p<0.001). Mean blood pressure differences were -1.1 mm Hg systolic (-3.3 to +1.1; p = 0.33) and -0.7 mm Hg diastolic (-2.2 to +0.8, p = 0.35) and the difference in the proportion with hypertension was -1.3% (-5.1 to 2.5, p = 0.56). Conclusion There were clear differences in population sodium and potassium intake between villages that were most likely a consequence of increased use of salt substitute. The absence of effects on blood pressure reflects the moderate changes in sodium and potassium intake achieved. Trial Registration Clinicaltrials.gov identifier: NCT01259700.

Rationale, design, and baseline characteristics of the Salt Substitute and Stroke Study (SSaSS)-A large-scale cluster randomized controlled trial.

Lowering sodium intake with a reduced-sodium, added potassium salt substitute has been proved to lower blood pressure levels. Whether the same strategy will also reduce the risks of vascular outcomes is uncertain and controversial. The SSaSS has been designed to test whether sodium reduction achieved with a salt substitute can reduce the risk of vascular disease. The study is a large-scale, open, cluster-randomized controlled trial done in 600 villages across 5 provinces in China. Participants have either a history of stroke or an elevated risk of stroke based on age and blood pressure level at entry. Villages were randomized in a 1:1 ratio to intervention or continued usual care. Salt substitute is provided free of charge to participants in villages assigned to the intervention group. Follow-up is scheduled every 6months for 5years, and all potential endpoints are reviewed by a masked adjudication committee. The primary end point is fatal and nonfatal stroke, and the 2 secondary endpoints are total major cardiovascular events and total mortality. The study has been designed to provide 90% statistical power (with 2-sided α = .05) to detect a 13% or greater relative risk reduction for stroke. The power estimate assumes a primary outcome event rate of 3.5% per year and a systolic blood pressure difference of 3.0mm Hg between randomized groups. Recruitment is complete and there are 20,996 participants (about 35 per village) that have been enrolled. Mean age is 65years and 49% are female. There were 73% enrolled on the basis of a history of stroke. The trial is well placed to describe the effects of salt substitution on the risks of vascular disease and death and will provide important policy-relevant data.

Cost and cost-effectiveness of a school-based education program to reduce salt intake in children and their families in China

Objective The School-based Education Program to Reduce Salt Intake in Children and Their Families study was a cluster randomized control trial among grade five students in 28 primary schools and their families in Changzhi, China. It achieved a significant effect in lowering systolic blood pressure (SBP) in all family adults by 2.3 mmHg and in elderlies (aged > = 60 years) by 9.5 mmHg. The aim of this study was to assess the cost-effectiveness of this salt reduction program. Methods Costs of the intervention were assessed using an ingredients approach to identify resource use. A trial-based incremental cost-effectiveness ratio (ICER) was estimated based on the observed effectiveness in lowering SBP. A Markov model was used to estimate the long-term cost-effectiveness of the intervention, and then based on population data, extrapolated to a scenario where the program is scaled up nationwide. Findings were presented in terms of an incremental cost per quality-adjusted life year (QALY). The perspective was that of the health sector. Results The intervention cost Int

Effect of salt reduction on iodine status in children and their families in northern China: a sub-study of a cluster-randomised controlled trial

19.04 per family and yielded an ICER of Int

Sodium and potassium content of 24 h urinary collections: a comparison between field- and laboratory-based analysers

2.74 (90% CI: 1.17–12.30) per mmHg reduction of SBP in all participants (combining children and adult participants together) compared with control group. If scaled up nationwide for 10 years and assumed deterioration in treatment effect of 50% over this period, it would reach 165 million families and estimated to avert 42,720 acute myocardial infarction deaths and 107,512 stroke deaths in China. This would represent a gain of 635,816 QALYs over 10-year time frame, translating into Int

OS 03-05 EFFECT OF SALT REDUCTION ON IODINE STATUS ASSESSED BY 24 H URINARY IODINE EXCRETION IN CHILDREN AND THEIR FAMILIES IN NORTHERN CHINA: A CLUSTER RANDOMISED CONTROLLED TRIAL.

1,358 per QALY gained. Conclusion Based on WHO-CHOICE criteria, our analysis demonstrated that the proposed salt reduction strategy is highly cost-effective, and if scaled up nationwide, the benefits could be substantial. Trial registration ClinicalTrials.gov NCT01821144

OS 03-04 INFLUENCE OF FAMILY AND PEER NETWORKS ON SALT REDUCTION IN CHILDREN IN THE SCHOOL-EDUSALT (SCHOOL BASED EDUCATION PROGRAMME TO REDUCE SALT) TRIAL

Abstract Background Salt reduction is a very cost-effective measure to reduce the risk of cardiovascular disease. Meanwhile, salt has been used as a vehicle for iodine fortification to prevent iodine deficiency. It is therefore important to monitor iodine status after salt intake is reduced. Methods This is a prespecified sub-study of the School-EduSalt trial (School-based Education Programme to Reduce Salt), a cluster-randomised controlled trial in Changzhi, northern China, where universal salt iodisation is mandatory. Primary schools were randomly assigned (1:1) to either the intervention or the control group with stratification by the location of schools (ie, urban or suburban) and the size of the class. The randomisation was done using a computer-generated random number system by an independent statistician who was blinded to the identity of the schools. The randomisation took place after written consents had been obtained and the baseline assessments had completed. Therefore, the participants, the school teachers, and the local investigators who undertook participant recruitment and data collection, were unaware of the allocation until the point prior to the commencement of the intervention. Children were eligible for inclusion if they ate homemade meals for at least 3 days a week and if their home was less than 3 km from the school. From each childs family we also enrolled two adults who shared the same meals with the child. Children in the intervention group were educated on how to reduce salt. They then delivered the message to their families. The duration was one school term (about 3·5 months). Urinary iodine was measured by ammonium persulfate digestion with spectrophotometric detection of the Sandell-Kolthoff reaction. The primary outcome was iodine intake as measured by repeat 24 h urinary iodine excretion. All participants who entered the School-EduSalt trial were included in this sub-study. The analysis was carried out on intention-to-treat basis. We used linear mixed models with adjustment of clustering and potential confounding factors. Logarithmic transformed iodine was used in the analysis. This trial is registered with ClinicalTrials.gov, number NCT01821144. Findings We enrolled 28 primary schools: 279 children (mean age 10·1 years [SD 0·5] and 553 adults (43·8 years [12·2]). At baseline, the mean salt intake was 7·0 g/d (SD 2.5) for children and 11·7 g/d (4·4) for adults, and the median iodine intake was 165·1 μg/d (IQR 122·6–216·7) for children and 280·7 μg/d (IQR 205·1–380·9) for adults. During the study both salt and iodine intake decreased in the intervention group compared with the control group. The mean effect on salt for intervention versus control was –1·9 g/day (95% CI –2·6 to –1·3; p Interpretation A 25% reduction in salt intake was associated with a significant reduction in iodine consumption in northern China where salt is iodised. Despite this, iodine intake was still adequate. Our findings indicate that meeting the WHO target of a 30% reduction in salt intake by 2025 will not compromise iodine status. Funding UK Medical Research Council (MR/J015903/1) and National Natural Science Foundation of China (81330064, 81273057).