## 4 Discussion  
The main objective of this study was to investigate the utility of obesity indicators for predicting hypertension among older persons in the rural community of Limpopo Province, South Africa. The study determined the prevalence of general obesity, abdominal obesity and hypertension and, thereafter, the relationship between obesity indicators and hypertension. The area under the ROC curve (AUC) was used to assess a certain indicator's potential to predict overall hypertension and either increased SBP or increased DBP. Regarding the socio-demographic status, the current study reported a high level of low literacy and dependence on old age grants among the participants in the Vhembe District, similar to other reports in South Africa [36; 48; 49; 50]. Generally, this study showed a 46% rate of hypertension among older persons. The reported prevalence of hypertension in this study is lower than the prevalence reported in South Africa (77.9%) among older persons [26; 51] and in other LMICs, such as Ghana \begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**Anthropometric Index** & **AUC (95\% CI)** & **Cut-Off Point** & **Sensitivity (\%)** & **Specificity (\%)** & _p-Value_ \\ \hline Men & & & & & \\ \hline BMI & 0.603 (0.52; 0.69) * & 27.50 & 61 & 57 & 0.026 \\ WHR & 0.505 (0.41; 0.60) & 0.96 & 55 & 47 & 0.914 \\ WHtR & 0.589 (0.50; 0.68) & 0.55 & 55 & 61 & 0.053 \\ WC & 0.582 (0.49; 0.67) & 87.50 & 62 & 55 & 0.077 \\ \hline Women & & & & & \\ \hline BMI & 0.554 (0.47; 0.64) & 29.04 & 62 & 53 & 0.208 \\ WHR & 0.497 (0.41; 0.58) & 0.90 & 50 & 43 & 0.954 \\ WHtR & 0.605 (0.52; 0.69) * & 0.58 & 61 & 55 & 0.014 \\ WC & 0.640 (0.56; 0.72) * & 90.50 & 67 & 57 & 0.001 \\ \hline \hline \end{tabular}
* Significant difference (_p_ < 0.05).  
\end{table} 
Table 4: The area under the ROC curve (AUC) to predict hypertension among men and women. \begin{table}
\begin{tabular}{c c c c c} \hline \hline
**Variable** & **Model 1** & **Model 2** & **Model 3** & **Model 4** \\  & **AOR (95\% CI)** & **AOR (95\% CI)** & **AOR (95\% CI)** & **AOR (95\% CI)** \\ \hline Men & & & & \\ \hline BMI (\(\geq\)25 kg/m\({}^{2}\)) & 1.84 (0.78; 4.62) & 1.77 (0.74; 4.51) & 1.78 (0.74; 4.55) & 1.57 (0.61; 4.30) \\ WHR (\(\geq\)0.90) & 0.51 (0.18; 1.42) & 0.49 (0.16; 1.40) & 0.49 (0.16; 1.42) & 0.43 (0.13; 1.38) \\ WHtR (\(\geq\)0.50) & 1.58 (0.73; 3.42) & 1.62 (0.74; 3.53) & 1.62 (0.74; 3.53) & 1.20 (0.49; 2.88) \\ WC (\(\geq\)90 cm) & 0.86 (0.35; 2.10) & 0.85 (0.34; 2.10) & 0.84 (0.34; 2.09) & 0.58 (0.19; 1.66) \\ \hline Women & & & & \\ \hline BMI (\(\geq\)25 kg/m\({}^{2}\)) & 0.99 (0.42; 2.40) & 1.04 (0.43; 2.57) & 1.01 (0.41; 2.50) & 1.17 (0.42; 3.37) \\ WHR (\(\geq\)0.90) & 0.90 (0.36; 2.27) & 0.79 (0.31; 2.04) & 0.78 (0.30; 2.01) & 1.01 (0.33; 3.28) \\ WHtR (\(\geq\)0.50) & 1.11 (0.51; 2.45) & 1.11 (0.50; 2.46) & 1.11 (0.51; 2.48) & 0.83 (0.34; 2.03) \\ WC (\(\geq\)90 cm) & 2.99 (0.94; 10.75) & 2.93 (0.92; 10.55) & 2.86 (0.89; 10.34) & 1.22 (1.16; 1.79) * \\ \hline \hline \end{tabular}  
* Significant difference (_p_ < 0.05). Model 1: BMI, WHR, WC, Model 2: BMI, WHR, WHC, age; Model 3: BMI, WHR, WHtR, WC, age, smoking, alcohol; Model 4: BMI, WHR, WHR, WC, age, smoking and alcohol use, marital status, education, old age grant, family history of hypertension.  
\end{table} 
Table 5: Association of obesity indicators with hypertension. (57.1%) and Mexico (58.2%). However, a lower prevalence of hypertension among older persons in comparison to the current study has been reported in countries like Zambia (34.8%) [52] and Ethiopia (41.9%) [17], while similar prevalence has been reported in Nepal (44.9%) [53] and in Brazil (46.7%) [54]. Researchers have suggested that the increased prevalence of hypertension among older persons might be due to endothelial function, which contributes significantly to increased arterial stiffness in patients with isolated systolic hypertension and increased age [55; 56]. The present study also showed a higher prevalence of increased SBP (69%) than DBP (49%) among older persons.