Obesity has emerged as a pressing health concern for the United Arab Emirates (UAE) in recent years. Data extracted from the UAE National Health Survey Report of 2017–2018 reveals a high prevalence of obesity among adults, estimated at around 27.8% (1). This statistic indicates a broader health context dominated by non-communicable diseases (NCDs), which the World Health Organization (WHO) identifies as the primary cause of mortality in the region. In fact, NCDs account for 55% of all deaths in the UAE, with cardiovascular diseases (CVDs) emerging as the primary culprit, responsible for 34% of these fatalities (2). Therefore, addressing the increasing prevalence of obesity and its related health risks has become an urgent priority in the UAE.
Assessing obesity requires methods that are not only accurate but also cost-effective and efficient for use in large-scale settings. Weight and height measurements, offer a simpler and quicker alternative, with Body Mass Index (BMI) being a widely employed metric (3). BMI's limitations include its inability to differentiate between muscle, fat, bone, or vital organs, leading to misclassification of individuals with high fat-free mass (FFM) relative to stature as overweight or obese, and its failure to account for variations in body composition among individuals (4, 5). Moreover, body fat percentage (BF%) varies with age, sex, ethnicity, and individual differences, complicating the interpretation of BMI values (6). Although BMI has its limitations, it remains popular in epidemiological research. Alternative methods for assessing obesity, such as body fat-mass measurement techniques including Bioelectrical Impedance Analysis (BIA), Computed Tomography (CT), Magnetic Resonance Imaging (MRI), and Dual-Energy X-ray Absorptiometry (DXA), are considered more precise for the assessment of body composition.
Dual-energy X-ray Absorptiometry (DXA) is renowned as the gold standard in body composition assessment and is recognized for its precision and applicability in various settings (7–9). Unlike conventional X-ray systems, DXA requires special beam filtering and precise spatial registration to measure both whole-body bone mass and soft tissue composition (10). DXA utilizes a 3-compartment model, with compartments encompassing fat mass (FM), FFM, and bone mineral content. Increasing the number of compartments enhances accuracy, lowers the chances of measurement errors, and reduces the need for assumptions in determining body composition (11). DXA assessments are rapid, non-invasive, and entail minimal inconvenience for patients, further enhancing its appeal in clinical practice and research (12). However, despite its advantages, DXA does have drawbacks, including the requirement for expensive specialized radiology equipment, small radiation exposure, and the need for trained technicians, which may limit its feasibility in routine clinical practice (12, 13).
To address these challenges, BIA has been suggested to assess body composition. BIA serves as an indirect method for assessing body composition, relying on parameters such as impedance and phase angle to calculate various body compartments (14). It utilizes the body's electrical properties to gauge resistance to an electric current, factoring in weight, height, and age to estimate total body water (TBW). Then applies equations to accurately determine BF% (6, 15). BIA, a two-compartment model, operates under the assumption of constant FFM density. However, significant water fluctuations during growth and development can lead to inaccuracies in body composition measurements (13). Other factors including device type, water distribution, hydration status, weight, and height, may increase the risk of inaccurately assessing FFM (6, 16). BIA is safe, simple, non-invasive, and cost-effective, making it increasingly popular for evaluating body composition in clinical and research settings (12, 13, 17, 18) It has emerged as a popular alternative to DXA for assessing body composition (9). BIA’s advantages, such as portability, affordability, minimal training requirements, and lack of radiation exposure, make it a practical option for assessing body composition in both clinical practice and large-scale epidemiological studies (15, 16, 19–21). However, the accuracy of predictive equations for estimating TBW depends on factors such as the type of BIA device used to record impedance data, the reference method employed to assess FFM, and the characteristics of the population in which the equation was developed (22).
BIA devices incorporate predictive equations for body fat that were originally developed using data from specific demographic groups (4, 12). Many of these equations were initially derived from studies involving predominantly white populations and subsequently applied to individuals from diverse ethnic backgrounds. However, research indicates that there are variations in body composition among different ethnic groups, potentially impacting the precision of BIA measurements (23–26). Hence, past research suggests the necessity for customized BIA equations tailored to specific ethnic groups (27, 28). Currently, there is a lack of research comparing BIA and DXA in the UAE. Therefore, the aim of this study was to examine the agreement between BIA and DEXA measurements of BF% among females.