Body composition-derived abdominal circumference, waist-to-hip ratio, and waist-to-height ratio cut-offs for Ethiopian adults in Northwest Ethiopia, 2023.

Background: Central and general obesity are commonly measured using tools like waist circumference (WC), hip circumference (HC), waist-to-hip ratio (WHR), and waist-to-height ratio (WHtR). However, the universally recognized cutoffs for these measures may be inadequate for individuals of Ethiopian descent. Due to the lack of universally applicable cutoffs, studies recommend tailoring the optimal screening thresholds to each population's specific characteristics. Therefore, this study aimed to determine body composition-based WC, WHR, and WHtR cutoffs for the healthy adult population of Ethiopia.

Method: A population based cross-sectional study was conducted in the Amhara region of Ethiopia from June to August 2023, collecting anthropometric and body composition data from 838 adult participants. Data were analyzed using Stata, and MedCalc software. The cut-off values were determined using ROC analysis, and performance was assessed using area under the curve (AUC), Youden index, sensitivity, and specificity.

Result: The optimal cut-off values for WC, HC, WHR, and WHtR to define obesity in men were 85.0 cm, 93.5 cm, 0.89, and 0.53 respectively. Correspondingly, these values in women were 81.1 cm, 97.2 cm, 0.84, and 0.5. These cutoff values showed the highest effectiveness in defining obesity especially for WC and WHtR. The new proposed cutoff values for waist circumference, hip circumference, and waist-to-height ratio had sensitivity ranging 76-93% and specificity of 83-94% in accurately identifying obesity. The current study also determined the cut-off values for underweight, normal weight, and overweight body weight categories. Accordingly, for men, the WC cut-offs were: ≤ 74.55 cm (underweight), 74.56-78.95 cm (normal), and 79.0-85.0 cm (overweight). For women, the cut-offs were: ≤ 68.25 cm (underweight), 68.26-79.59 cm (normal), and 79.60-81.10 cm (overweight). The WHtR thresholds were: ≤0.43 (underweight), 0.44-0.47 (normal), and 0.48-0.53 (overweight) in men; ≤0.43 (underweight), 0.44-0.50 (normal), and 0.50-0.51 (overweight) in women.

Conclusion: The findings indicate that the WC, WHR, and WHtR cutoff values for defining obesity in Ethiopian adults are lower than international standards. The newly proposed cutoff values showed improved sensitivity and specificity, suggesting their potential diagnostic relevance. Considering these country-specific cutoffs may be beneficial for clinical practice and obesity-related research in Ethiopia.