Modelling of South African child hypertension-application of panel quantile regression

Abstract

Introduction: Hypertension in children is an emerging public health concern that has traditionally received limited attention, particularly in developing countries such as South Africa

Objective: This study addresses a methodological gap by modeling pediatric hypertension in South Africa using panel quantile regression analysis, aiming to uncover the heterogeneous effects of key predictors across the blood pressure distribution over time.

Methods: Data were obtained from the South African National Income Dynamics Study Household Surveys conducted in 2014–2015 (Wave 4) and 2017 (Wave 5). We constructed a balanced panel of 103 adolescents (<18 years) who participated in both Waves 4 and 5. Panel quantile regression was applied to examine predictors of blood pressure over time.

Results: The prevalence of child hypertension based on abnormal systolic blood pressure increased slightly from 16.5% in 2014–2015 to 21.4% in 2017. Age, body mass index, gender, exercise frequency, cigarette use, depression, and perceived health status were identified as significant predictors of elevated systolic blood pressure or diastolic blood pressure over time. Fixed-effects and random-effects specifications produced identical point estimates.

Conclusion: These results underscore the importance of targeted interventions that consider modifiable lifestyle and psychosocial factors when addressing hypertension among South African children.

Keywords

Child hypertension / South Africa / Panel quantile regression / Random-effects model / Fixed-effects model

Acknowledgements

The authors sincerely thank the South African National Income Dynamics Study (NIDS) 2014–2015 (Wave 4) and 2017 (Wave 5) study teams for granting permission to use their data.

Funding

None.

Conflict of interest

The authors declare that they have no conflicts of interest.

Author contributions

Conceptualization:Anesu Gelfand Kuhudzai

Investigation: Anesu Gelfand Kuhudzai

Methodology: Anesu Gelfand Kuhudzai

Formal analysis: Anesu Gelfand Kuhudzai Supervision: Kolentino Mpeta

Writing–original draft: Anesu Gelfand Kuhudzai

Writing–review & editing: All authors

Ethics approval and consent to participate

The South African National Income Dynamics Study was conducted with ethical approval from the Ethics Committee of Faculty of Commerce, University of Cape Town (ethical approval no.: REC 20202/04/017). All participants provided informed consent prior to participation.

Consent for publication

Not applicable as this study utilised secondary data obtained from the South African National Income Dynamic Study Wave 4 and Wave 5.

Availability of data

The dataset analyzed during the current study is available from the corresponding author upon reasonable request.

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