Effect of individual health perception, health consultation, and other risk factors on undiagnosed hypertension in South Africa

Similar to other nations, hypertension control is a challenge for public health in South Africa. To control hypertension, the condition must be screened and diagnosed in the public health system. This study examines how the prevalence of undiagnosed hypertension is influenced by various risk factors including demographic, socioeconomic, environmental, and behavioural factors, with primary focus on self-perceived health well-being and time since the last healthcare consultation. The study utilized data from the National Income Dynamics Study (NiDS), a panel survey conducted approximately every two years between 2008 and 2017. Participants aged 15 years and older with at least two blood pressure measurements were included. The sample included 15,712 unique individuals (60.0% women) and 31,340 observations from the five survey waves (5,357 in 2008; 5,206 in 2010/11; 6,385 in 2012; 7,060 in 2014/15; and 7,332 in 2017). Both descriptive and analytical methods were used to study undiagnosed hypertension. Multilevel logistic regression was used to explore the relationship between undiagnosed hypertension with various risk factors including perceived health well-being and time since last health consultation. The study showed that in 2008 (wave 1) and in 2017 (wave 5), approximately 53.5% and 42.6% respectively, of individuals aged 15 and above were unaware they could be hypertensive. Those who perceived their health as very good or excellent were respectively 2.15, 95% CI [1.89–2.44] and 3.29, 95% CI [2.85–3.80] times more likely to have undiagnosed hypertension, compared to those who perceived their health as fair or poor. Additionally, the risk of having undiagnosed hypertension increased gradually with time since last consultation on one’s health. Those whose last consultation was more than two years ago were 12.10, 95% CI [10.50–13.90] times more likely to have undiagnosed hypertension compared to those who had consulted within the last 30 days. Given that hypertension is often asymptomatic, self-perceived health can be misleading. This underscores the need for health programs to emphasize the importance of regular blood pressure checkups. Regular consultations with healthcare providers are crucial for early detection and management of hypertension.