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

Abstract

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.

Analysis of cluster randomised trials with an assessment of outcome at baseline

“…This approach was used by He and colleagues to evaluate a school based education programme aimed at reducing salt intake in children and their families (box 1). 4…”

Prevention and Control of Cardiovascular Disease in the Rapidly Changing Economy of China

“…56 The China Salt Substitute Study demonstrated, among 608 individuals with high cardiovascular risk from rural northern China, after 12 months of intervention with salt substitute, systolic blood pressure was significantly reduced by 5.4 mm Hg (P=0.001) on average in comparison with the regular salt group. 57 The blood pressure lowering effect of salt substitute has been reconfirmed in trials in patients with hypertension in other Chinese populations.…”

“…The examples of implementation research in prevention and control of CVD in China include the Simplified Cardiovascular Management Study (SimCard), 178 school based education programme to reduce salt intake in children and their families (School EduSalt), 56 China Rural Health Initiative (CRHI) 179, 180 , CPACS, 181, 182 China Da Qing Diabetes Prevention Study, 183 etc. 184 For example, the recently completed SimCard trial demonstrated that a simplified cardiovascular management program, only two drugs (anti-hypertensive and aspirin) and two lifestyle recommendations (smoking cessation and salt reduction), delivered by community health workers with the aid of a smartphone-based electronic decision support system, was effective 178 .…”

Impact of a hospital-based educational intervention on dietary salt-related knowledge and behaviour in a cardiac care unit population in Lebanon

“…In parallel to national initiatives smaller scale salt-reduction interventions have been shown to be effective in reducing salt intake. For example, a recent school-based educational intervention was shown to reduce salt consumption of both the children exposed to the intervention and their families (16). The lack of national salt-reduction initiatives in low-to middleincome countries, such as Lebanon, could be attributed to limited funding and organizational infrastructure at governmental level.…”