Anthropometric Linear Measurements as Surrogate Marker in Low Birth Weight Infants: A Cross-sectional Study

Abstract

Introduction: Low Birth Weight (LBW) is linked to perinatal mortality and morbidity, growth, and cognitive developmental defects, along with a greater tendency to develop non communicable diseases later in life. In many settings, the birth weight of infants is not properly noted; weight is either not measured appropriately or tabulated accurately. This has necessitated the use of alternative indices in lieu of birth weight to reliably identify LBW babies, especially in settings where the availability of weighing scales is very limited. Aim: To determine the reliability of anthropometric measurements as a surrogate marker of weight in LBW infants born in a tertiary care hospital. Materials and Methods: This hospital-based cross-sectional study was conducted at Department of Paediatrics and Neonatology, Assam Medical College, Dibrugarh, Assam, India from March 2023 to May 2023. Admitted inborn babies (n=2074) in the postnatal ward and inborn Neonatal Intensive Care Unit (NICU) were included. LBW was defined as <2500 grams. Crown-heel Length (CHL), Chest Circumference (CC), Head Circumference (HC), and Mid-upper Arm Circumference (MUAC) were measured. Student’s t-test and Receiver Operating Characteristic (ROC) curve analysis were used to statistically analyse the data. Results: Out of the 2074 included babies, 1123 were male, and 471 were LBW. The mean birth weight of the LBW cohort was 1.98±0.45 kg compared to 2.78±0.33 kg in the NBW cohort (p-value<0.05). CHL, CC, HC, and MUAC were all significantly lower in the LBW cohort compared to the NBW cohort. MUAC seemed to be the best indicator of LBW. The cut-offs for CHL, HC, CC, and MUAC were 48.5cm, 33.5cm, 30.5cm, and 10.5cm, respectively. Conclusion: The MUAC was strongly correlated with birth weight. MUAC is easy to obtain, simple to perform, and does not require sophisticated equipment.