CARDIOVASCULAR JOURNAL OF AFRICA • Volume 34, No 3, July/August 2023 162 AFRICA and the regulation of uric acid transporters, specifically ABCG2 and SLC2A9.26 Hypertensive disorders of pregnancy (HDP) have been linked in many studies to increased risk for future hypertension.27-29 Gestational hypertension in our study was self-reported and we were unable to differentiate between the different subtypes of HDP. Studies have shown that women with gestational hypertension or pre-eclampsia are two to three times more likely to develop chronic hypertension than women with normotensive first pregnancies.27,30,31 The mechanism behind this is not clearly understood. It is thought that HDP could unmask underlying cardiovascular risk already present due to the ‘stress’ of pregnancy or that pregnancy could induce endothelial or organ damage, altering the woman’s trajectory towards cardiovascular risk-factor development.27 Regardless of the underlying mechanism, these women represent a large proportion of society who could be monitored for the development of hypertension with appropriate institution of treatment prior to the development of complications. Studies conducted with synthetic progesterone used for contraception or hormone replacement therapy have shown an elevating effect on BP.32,33 This is thought to be due to an increase in sodium retention as well as androgenic properties of synthetic progesterone.34,35 An Ethiopian study of 100 women (50 using injectable progesterone and 50 controls) found no difference in BP between the two groups.36 Two-thirds of the females who were using some form of contraception were using injectable progesterone in our cohort and this was found to be associated with a 4.6-mmHg higher SBP than those females on no contraception. This is also a modifiable factor that could prevent hypertension in young pre-menopausal women. There are some limitations to the study. As the study sample was derived from a cohort of participants who were seen at age 22 years and screened for EBP, we could have created a bias towards those with higher BPs at age 22 returning aged 28 years. As BMI showed such a strong association, more information relating to dietary patterns, physical activity, sedentary behaviours and sleep would have been useful. Conclusion We found a significant association of higher BPwith albuminuria, suggesting that vascular or subclinical renal damage may already be present at a young age. Although we found no association with eGFR, possibly as our cohort was too young for this effect to be noticeable, we have a good baseline to follow this cohort up in future to assess decline in eGFR. Our findings suggest that the underlying pathophysiology of EBP in young adults differs in men and women. They also highlight the negative impact of HDP and injectable contraceptives on the development of EBP in women. These findings are important as this population group has a very high prevalence of hypertension and end-stage kidney disease secondary to hypertension occurring in a relatively younger age group. We are grateful to the BT20 participants for being a part of the study and to the data-collection team for their support. BT20 is funded by University of the Witwatersrand, Johannesburg, South African Medical Research Council, Human Sciences Research Council of South Africa and the Wellcome Trust (UK). The work reported herein was made possible through funding by the South African Medical Research Council through its Division of Research Capacity Development under the Clinician Researcher Development PhD Scholarship Programme from funding received from the South African National Treasury. The study was jointly funded by the South African MRC, MRC UK (via the Newton Fund), and GSK Africa Non-Communicable Disease Open Lab (via a supporting grant project number: 074). Additional sources of funding were obtained from the International Society for Nephrology (ISN) Clinical Research Program: 15-2-015_ Validation of eGFR equations in South Africans (South Africa); the National Health Laboratory Services (NHLS); Faculty of Health Sciences Research Incentive Grant; grant number: 0012838434203512110500000000000000004 550; University of the Witwatersrand; FHS (Wits). Authors retained control of the final content of the publication. SAN is supported by the DSI-NRF Centre of Excellence in Human Development at the University of the Witwatersrand, Johannesburg, South Africa. References 1. Zhou B, Perel P, Mensah GA, Ezzati M. Global epidemiology, health burden and effective interventions for elevated blood pressure and hypertension. Nat Rev Cardiol 2021; 18(11): 785–802. 2. Lindhorst J, Alexander N, Blignaut J, Rayner B. Differences in hypertension between blacks and whites: an overview. Cardiovasc J Afr 2007; 18(4): 241–247. 3. 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