Objective: To determine the most appropriate cut-off values of Waist Circumference (WC) and Waist-to-Height Ratio (WHtR) for diagnosing moderate acute malnutrition (MAM) and severe acute malnutrition (SAM) in under-five children.
Methods: This cross-sectional diagnostic accuracy study was conducted between January 2021 and August 2022 in the Department of Pediatrics of a tertiary hospital in Delhi. Children aged 6 months to 5 years attending the outpatient or emergency services were included in the study. Detailed clinical evaluation and anthropometry including measurement of WC were done at enrollment. Body mass index (BMI) and WHtR were calculated. Malnutrition was classified as per the WHO criteria. Receiver operating characteristic curves (sensitivity, specificity) for WC and WHtR (absolute values) were drawn against the standard test of WHO definitions for MAM and SAM to determine the most appropriate cut-offs for diagnosing MAM and SAM.
Results: 1500 children with a median (IQR) age of 29 (14, 43) months were enrolled; 21% children had MAM and 11% had SAM as per the WHO criteria. WC < 44.5 cm (sensitivity 74.1%, specificity 71.1%) and WHtR < 0.565 (sensitivity 75.6%, specificity 33.7%) was the best cut-off to identify MAM, whereas WC < 42.3 cm (sensitivity 67.5%, specificity 81.3%) and WHtR < 0.563 (sensitivity 81.3%, specificity 33.4%) was the best cut-off to diagnose SAM.
Conclusions: Waist circumference (< 44.5 cm for MAM; < 42.3 cm for SAM) had a reasonably good sensitivity and specificity for diagnosing MAM and SAM, but the same was not true for WHtR.