Background: Body mass index (BMI) is often used by dietitians in practice as part of their nutritional assessment of patients (1). However, waist-to-height ratio (WHtR) is more closely associated with health risk in overnutrition than BMI (2). WHtR requires the measurement of waist circumference. At present, there is little published information about dietitians’ views and use of WC but this would be useful to understand their choice of assessment methods and whether using WHtR could be included. The present study aimed to investigate dietitians’ knowledge and use of WC and WHtR in practice.
Methods: Dietitians (n=235) who had participated in a student anthropometric practical that included measuring WC and been given a tape measure to keep during their pre-registration training at one university were contacted by email between one to eight years after graduation and invited to participate in an online cross-sectional survey. Questions were developed specifically for the survey and focused on (i) use of BMI and WC measurements in practice (ii) views and practicalities of the use of BMI and WC measurements in practice (iii) knowledge of anthropometric ranges and cut-off values for health risk associated with BMI and WHtR. Demographic variables were collected. Fisher’s exact probability test was used to analyse responses to questions with categorical answers and open questions were thematically analysed. The study was ethically approved and participating in the survey was considered to be giving implied consent.
Results: Twenty-eight dietitians (12%) participated. All of them used BMI in practice and 25% also used WC. (i) Dietitians were significantly more likely to use WC when working in diabetes (P=0.009) and cardiovascular disease (P=0.021) than in weight management, undernutrition or renal disease; (ii) ‘unfamiliarity’ was the most common reason for not using WC and/or WHtR but dietitians who used them considered them ‘useful’; (iii) most dietitians knew the BMI ranges associated with healthy weight (100%), overweight (100%) and obesity (96%) but few were aware of the maximum WHtR associated with low cardiometabolic risk in men (36%) and women (11%).
Discussion: WC and WHtR measurements are relevant to assessment in overnutrition but not undernutrition so it is logical that dietitians working in diabetes and cardiovascular disease are more likely to use them even though overall use was low. Use in weight management was surprisingly low but this might reflect the perceived practical difficulty and sensitivity of measuring WC in this population which has been previously reported in general practice (3). Although all participants were known to have taken part in previous training in WC measurement, for some this was up to 8 years earlier. Their lack of familiarity with the procedure and ability to interpret values indicate more training is needed before WHtR can be considered as a routine nutrition assessment tool. However, the low response rate and recruitment and data collection methods limit the generalisability of results so further evidence is needed to confirm this need for training.
Conclusion: This small study showed that dietitians’ use and knowledge of WC and WHtR is low but that these are more likely to be used by those working in diabetes and cardiovascular disease.References1Madden, A.M. & Smith, S. (2016) Body composition and morphological assessment of nutritional status in adults: a review of anthropometric variables. J. Hum. Nutr. Diet. 29:7-25.2Ashwell, M. & Gibson, S. (2016) Waist-to-height ratio as an indicator of 'early health risk': simpler and more predictive than using a 'matrix' based on BMI and waist circumference. BMJ Open 3:1-7.3Dunkley, A.J., Stone, M.A., Patel, N. et al., (2009) Waist circumference measurement: knowledge, attitudes and barriers in patients and practitioners in a multi-ethnic population. Fam. Pract. 26:365-71.
|Number of pages
|Published - 5 Dec 2018
|British Dietetic Association Research Symposium 2018 - Birmingham, United Kingdom
Duration: 5 Dec 2018 → 5 Dec 2018
|British Dietetic Association Research Symposium 2018
|5/12/18 → 5/12/18