Study design and baseline characteristics of a combined educational and environmental intervention trial to lower sodium intake in Swiss employees

Abstract

BackgroundBlood pressure is a primary cardiovascular disease risk factor. Population-wide governmental strategies aim to reduce lifestyle and dietary risk factors for hypertension, one of which is an unbalanced diet with high sodium and low potassium intakes. Nutrition interventions in the workplace are considered a promising approach in encouraging health-promoting behaviors. We developed and conducted the health promoting sodium reduction trial “Healthful & Tasty: Sure!” in worksites in the German-speaking part of Switzerland from May 2015 to Nov 2016, for which we present the study protocol and baseline characteristics.MethodsHealthful & Tasty, a cluster nonrandomized single-arm trial with calibration arm, aimed to demonstrate the effectiveness of a combined educational and environmental intervention in the workplace in reducing employees’ average daily sodium/salt intake by 15%. To this end, health and food literacy of employees and guideline compliance among the catering facility team needed to be improved. The primary outcome measure was sodium/salt intake estimated from sodium excretion in a 24-h urine sample. Secondary outcome measures included changes in the overall qualitative diet composition, blood pressure, anthropometric indices, and health and food literacy.Of eight organizations with catering facilities, seven organizations took part in the nutrition education and catering salt reduction interventions, and one organization participated as a control. Overall, 145 consenting employees were included in the staggered, one-year four-phase trial, of which 132 participated in the intervention group. In addition to catering surveys and food sampling, the trial included five follow-up health assessments including questionnaires, blood pressure measurements, anthropometrics, and sodium, potassium, and iodine intake measurements obtained from 24-h and spot urine samples, and a food record checklist. Exploratory and hypothesis generating baseline statistical analysis included 141 participants with adequate 24-h urine samples.DiscussionDespite practice-driven limitations to the study design and small cluster and participant numbers, this trial has methodological strength and will provide important insights into the effectiveness of a combined educational and environmental intervention to reduce salt intake among female and male Swiss employees.Trial registrationGerman Clinical Trials Register, DRKS00006790. Registered 23 September 2014.

RE-AIM evaluation of a one-year trial of a combined educational and environmental workplace intervention to lower salt intake in Switzerland

“…A detailed description of the study protocol along CONSORT guidelines is available elsewhere (Beer-Borst et al, 2018). Swissethics approved the trial that was registered in the German Clinical Trials Register (DRKS00006790, 23.09.2014).…”

“…Due to recruitment problems (see Section 3.1 Adoption, below), the design was changed to a cluster nonrandomized single-arm trial with calibration arm. This alteration required participation of seven intervention clusters with a threshold of 112 participants before 10% dropout (Beer-Borst et al, 2018).…”

“…In the intervention group, participants attended the education program and had five individual follow-up health assessments. Measurements included blood pressure, heart rate, body weight, height (only t0), and waist and hip circumference from which body mass index (BMI) and waist-to-height ratio (WHtR) were calculated (Beer-Borst et al, 2018). Na/salt and K intakes were estimated using three methods during three-day periods at t0 and t12.…”

“…Na/salt and K intakes were estimated using three methods during three-day periods at t0 and t12. A food record checklist, which provided semiquantitative information on food sources of Na and K intake (day 1–3) (Beer-Borst et al, 2017), a late afternoon spot urine (day 2) and a 24-hour urine (day 3) collection according to standard procedures (Beer-Borst et al, 2018). Urine specimens were analyzed in a private accredited medical laboratory.…”

Cardiovascular health status and its associations with cardiovascular disease and ischemic heart disease prevalence in Australian adults

“…224 Recent studies documented the effectiveness of population-wide salt reduction programs in lowering the CVD risk. 225,226 A number of programs have conducted to reduce the salt intake in Australia. 227 However, there is no campaign to influence consumer behavior regarding salt and no mechanism to monitor the changes in salt intake national wide.…”