Botha J., De Ridder J.H., Potgieter J.C., Steyn H.S., Malan L.
Physical Activity Sport and Recreation (PhASRec), North-West University, Potchefstroom, South Africa; School for Psychosocial Behavioural Science, North-West University, Potchefstroom, South Africa; Statistical Consultation Service, North-West University, Potchefstroom, South Africa; Hypertension in Africa Research Team (HART), North-West University, Private Bag X6001, 2520 Potchefstroom, South Africa
Botha, J., Physical Activity Sport and Recreation (PhASRec), North-West University, Potchefstroom, South Africa; De Ridder, J.H., Physical Activity Sport and Recreation (PhASRec), North-West University, Potchefstroom, South Africa; Potgieter, J.C., School for Psychosocial Behavioural Science, North-West University, Potchefstroom, South Africa; Steyn, H.S., Statistical Consultation Service, North-West University, Potchefstroom, South Africa; Malan, L., Hypertension in Africa Research Team (HART), North-West University, Private Bag X6001, 2520 Potchefstroom, South Africa
A recently proposed model for waist circumference cut points (RPWC), driven by increased blood pressure, was demonstrated in an African population. We therefore aimed to validate the RPWC by comparing the RPWC and the Joint Statement Consensus (JSC) models via Logistic Regression (LR) and Neural Networks (NN) analyses. Urban African gender groups (N=171) were stratified according to the JSC and RPWC cut point models. Ultrasound carotid intima media thickness (CIMT), blood pressure (BP) and fasting bloods (glucose, high density lipoprotein (HDL) and triglycerides) were obtained in a well-controlled setting. The RPWC male model (LR ROC AUC: 0.71, NN ROC AUC: 0.71) was practically equal to the JSC model (LR ROC AUC: 0.71, NN ROC AUC: 0.69) to predict structural vascular disease. Similarly, the female RPWC model (LR ROC AUC: 0.84, NN ROC AUC: 0.82) and JSC model (LR ROC AUC: 0.82, NN ROC AUC: 0.81) equally predicted CIMT as surrogate marker for structural vascular disease. Odds ratios supported validity where prediction of CIMT revealed clinical significance, well over 1, for both the JSC and RPWC models in African males and females (OR 3.75-13.98). In conclusion, the proposed RPWC model was substantially validated utilizing linear and non-linear analyses. We therefore propose ethnic-specific WC cut points (African males, ≥90 cm; -females, ≥98 cm) to predict a surrogate marker for structural vascular disease. © Georg Thieme Verlag KG Stuttgart · New York.
gamma glutamyltransferase; glucose; high density lipoprotein; triacylglycerol; adult; Africa; aged; arterial wall thickness; article; artificial neural network; blood pressure measurement; body mass; cardiovascular risk; carotid artery; diastolic blood pressure; disease marker; energy expenditure; ethnicity; female; gamma glutamyl transferase blood level; glucose blood level; human; human tissue; logistic regression analysis; male; normal human; physical activity; priority journal; systolic blood pressure; triacylglycerol blood level; vascular disease; waist circumference; Adult; Africa; Aged; Biological Markers; Blood Glucose; Blood Pressure; Carotid Intima-Media Thickness; Female; Humans; Linear Models; Lipoproteins, HDL; Logistic Models; Male; Middle Aged; Models, Statistical; Neural Networks (Computer); Nonlinear Dynamics; Odds Ratio; Reproducibility of Results; ROC Curve; Sex Characteristics; Triglycerides; Urban Population; Vascular Diseases; Waist Circumference; Young Adult