The correlation between mid-upper Arm circumference and Body Mass index in the assessment of adult nutritional status in Malawi.

Abstract

Background Body Mass Index (BMI) is a widely used and accepted indicator of nutritional status in adults. Mid-Upper-Arm-Circumference (MUAC) is another anthropometric measure used primarily among children. While BMI remains the best indicator of nutritional status, it can sometimes be impractical because of logistical requirements for weight and height measurement, especially for large population-based studies and bed-ridden patients. Therefore, we analyzed anthropometric data collected from the Malawi Epidemiology and Intervention Research Unit (MEIRU) Non-Communicable Disease (NCD) survey to determine the correlation between BMI and MUAC in the assessment of adult nutritional status in Malawi. Methods A secondary data analysis utilizing descriptive and correlational statistical research methods was used to determine the relationship between BMI and MUAC in the assessment of adults’ nutritional status in Malawi. The data was analyzed using SPSS version 27. The independent t test and Chi-square were employed. Furthermore, the study included the Pearson correlation test to assess the relationship between variables. A p-value of <0.05 was considered statistically significant. Results The study assessed 30,575 participants, of whom the majority (61.8%) were females. The mean MUAC was 27.2 (SD = 3.300), and the mean BMI was 23.5 (SD = 4.55). The study found a strong positive statistically significant correlation between MUAC and BMI among Malawians (r = 0.836, CI = (0.832-0.839) such that for each additional centimeter increase in MUAC, BMI is expected to increase by approximately 1.153 units (BMI = -7.797 + 1.153 (MUAC)). There was a significant positive correlation between BMI and MUAC in both males and females and in rural and urban residents (P<0.01). The ROC curve was excellent for BMI in the overweight range (AUC = 0.87), and the findings were superior in the obese range (AUC = 0.956). Conclusion The correlation between MUAC and BMI is positive regardless of sex or rural/urban residence. Therefore, the MUAC can be used as a clinical test to predict BMI .