Hypertension management in a population of older adults in rural South Africa

Abstract

Objective Assess awareness, treatment, and control of hypertension, as an indication of its management, in rural South Africa, especially regarding modifiers of these variables. Methods A population-representative sample of adults aged at least 40 years residing in the rural Agincourt subdistrict (Mpumalanga Province) covered by a long-term health and sociodemographic surveillance system was recruited. In-person interviews, physical exams, and dried blood spots were collected. Hypertension awareness, treatment, and control rates were assessed. A regression model was built to identify predictors of those outcomes. Results The mean age of the 2884 hypertensive participants was 64.1 ± 12.7 years. Hypertension awareness rate was 64.4%, treatment among those aware was 89.3 and 45.8% of those treated were controlled. Considering aware and unaware hypertensives, treatment rate was 49.7% and control 22.8%. In the multivariable regression model, awareness was predicted by female sex, age at least 60 years, higher social economic status, prior cardiovascular disease (CVD), nonimmigrant status, literacy, and physical limitation. Improved control among those treated was predicted by age at least 60 years. Blood pressure control among all hypertensive study participants was predicted by female sex, being HIV-negative, age at least 60 years, nonimmigrant status, and prior CVD. Conclusion High rates of awareness and treatment of hypertension as well as good levels of control were found in this population, probably explained by the long-term surveillance program conducted in the area. Considering the predictors of hypertension management, particular attention should be given to men, residents younger than 60 years, immigrants, and study participants without CVD as these characteristics were predictors of poor outcome.

Disparities in Management of Cardiovascular Disease in Rural South Africa

“…Male sex, absence of physical disability and SES were positively associated with the number of risk factors controlled. Higher SES has been consistently associated with better risk factor control 47 in secondary prevention of CVD and even within the HAALSI cohort, hypertension was better managed in those individuals from higher SES 25 . A possible explanation for the male sex and absence of physical disability results might be related to a better adherence to treatment in these two groups, when compared to females and individuals with co-morbidities 48, 49 .…”

“…This may create a specific environment of improved health care surveillance that might increase the level of risk factor control among patients with CVD, when compared to subjects with CVD living in other parts of South Africa, as we previously showed in a study addressing hypertension management 25 . The low control rates of CVD risk factors, observed in this particular area under surveillance suggests that levels of risk factor’s control may be even worse at sites not covered by a HDSS.…”

“…Included in this model were variables previously reported as possible factors interfering with health management in this setting 25–29 , including illiteracy, immigration status, physical disability and SES. Male sex, absence of physical disability and SES were positively associated with the number of risk factors controlled.…”

“…Continuous variables were compared using T test (expressed in mean values and standard deviations, since they were normally distributed) and categorical variables using Chi Square test (expressed in absolute numbers and percentiles). The distribution of modifiable risk factors under control was assessed by HIV and immigration status, since these two conditions were highly prevalent in this cohort, have been shown to impact on NCD management in the region and yet need to be better studied 25 . A linear regression model was built to identify factors associated with the number of cardiovascular risk factors controlled.…”

“…The predictors included in this model were sex, PD, age, SES, HIV status, immigrant status and illiteracy. These variables were included because they were previously reported as possible factors interfering with health management in this setting 25–29 . The results are presented using β- coefficients and 95% confidence intervals; level of significance was set as 5%.…”