Friday, 22 May 2015

Mid-upper arm circumference as an alternative measure of adult undernutrition

Dr Md Nazmul Karim from SPHPM has co-authored a paper with researchers from International Centre for Diarrhoeal Disease Research, Bangladesh (ICDDRB). The paper sought to assess the use of Mid-upper-arm circumference (MUAC) as a measure to determine adults who are undernourished.

For those living in low-income regions, nutritional issues can be overlooked in adults. To better understand the nutritional status of adults living in these countries, an appropriate and accurate indicator is required. The Body Mass Index (BMI) has been commonly adopted as this indicator for most individuals. BMI is a non-invasive objective indicator of adiposity as well as being used as an anthropometric measure in determining nutritional status.

Whilst BMI is widely used, there are limitations in its usage and practicality. As the BMI requires both height and weight, this cannot always be obtained, especially in those who are immobile or severely ill. Patients may not be able to move out of their beds or cannot be lifted upright to measure height. Furthermore, it is not always an appropriate tool in women who are pregnant as there is extra tissue and the weight of the foetus. Given these circumstances, there is a need for an alternative measure that can effectively gather similar information.

The proposed alternative by the authors is the use of mid-upper arm circumference (MUAC), a simple reliable measure which doesn’t need vast amounts of equipment. This is generally used as an anthropometric indicator in measuring nutritional levels in children aged 11-14 and has also been used to detect malnutrition in adults in hospital setting. A Dutch study even showed that low MUAC is more effective in predicting mortality than low BMI in older adults. Present study was seeking to assess the possibility of using MUAC as a tool to detect undernutrition and furthermore, to provide a cut-off value to identify undernutrition in adults.

The authors used a cross-sectional study design with 650 adult attendants of patients admitted to ICDDRB Dhaka Hospital. MUAC, weight and height of these patients were measured and curve estimation was done to assess the linearity and correlation of BMI and MUAC. Sensitivity and specificity of MUAC against BMI<18.5 was determined. Separate Receiver-operating-characteristic (ROC) analyses were performed for male and female. Areas under ROC curve and Youden's index were generated to aid selection of the most suitable cut-off value of MUAC for under nutrition.

The results indicated that there was a statistically significant positive linear correlation between BMI and MUAC. The male r-value was 0.81 (p<0.001) and the female r-value was 0.828 (p<0.001). The MUAC cut off determined for males was <25.1 cm and for females was <23.9. Both of these figures parallel with the BMI cut off equivalent for undernutrition.

The authors conclude that the MUAC does have a close correlation with the BMI indicator. Given the ease of conducting a MUAC measurement and its relative simplicity, the authors suggest that this can be used as a feasible alternative to the BMI cut off for the purpose of identifying adult undernutrition.

You can read the full paper here.  

No comments:

Post a Comment


Related Posts Plugin for WordPress, Blogger...