Thresholds of Anthropometric Indices of Adiposity and Digit Ratio (2d:4d) for High Blood Pressure Among the Hausa Ethnic Group in Kano, Nigeria

Body adiposity measures and the ratio of the second-to-fourth digit (2D:4D) of the hand is documented to exhibit strong relationship with cardio-metabolic risk factors (CMRF). High blood pressure is a hall mark of CMRF. Globally, the predictors of CMRF do not demonstrate universal validity across ethnic groups. This cross-sectional study was therefore aimed at determining the cut-off values (COV) of the anthropometric indices adiposity and 2D:4D for HBP among the Hausas of Kano. The study included 465 (266 males and 199 females) subjects, with a mean age of 34.4 years and 32.0 years for males and females respectively. Systematic random sampling technique was employed. Adiposity indices and 2D:4D were measured using standard anthropometric techniques. Systemic blood pressure was measured following standard clinical procedures. SPSS version 20 (IBM Corporation, NY) software was used for statistical analysis and Receiver operating characteristic (ROC) curve was used to determine the COV of 2D:4D and adiposity indices for HBP. The COV of body mass index (BMI), waist circumference (WC), hip circumference (HC), neck circumference (NC), waist-to-hip ratio (WHR), waist-to- height ratio (WHtR), body adiposity index (BAI), right digit ratio (R2D:4D) and left digit ratio (L2D:4D) for diastolic blood pressure (DBP) in males and females were 23.24 kg/m2, 79.45cm, 88.05cm, 34.95cm, 0.87, 0.47, 18.20, 0.97, 0.97 and 23.32 kg/m2, 72.15cm, 88.05cm, 31.32cm, 0.87, 0.43, 27.52, 0.98, 0.99 respectively. While COV of BMI, WC, HC, NC, WHR, WHtR, BAI, R2D:4D and L2D:4D for systolic blood pressure (SBP) in males and females were 24.10 kg/m2, 76.65cm, 89.30cm, 35.05cm, 0.89, 0.45, 26.15, 0.97, 0.98 and 23.32 kg/m2, 71.95cm, 88.05cm, 31.05cm, 0.87, 0.43, 27.52, 0.97, 0.98 respectively. Conclusively, Digit ratio has a threshold for HBP and the COV of adiposity indices for HBP in Hausas are slightly different from the commonly adopted values.

Key Words: Cut-off values, adiposity indices, digit ratio, high blood pressure, Kano