Hypertension in adolescents and young adults at a tertiary clinic in Cape Town, South Africa
Background: The prevalence of essential hypertension in children and adolescents has increased dramatically over the past decade attributed to a rising prevalence of obesity, high salt diet and lack of exercise. Traditionally high blood pressure in adolescents required extensive work up to determine a cause, but given the changing demographics this policy needs to be reviewed.
Objectives/method: The study aimed describe the risk factors, demographics, target organ damage and aetiology of hypertension in a cohort of young hypertensives (aged 15 - 30 years) referred to a tertiary hypertension clinic at Groote Schuur Hospital, by retrospectively reviewing the folders over a three-month period. Results: Thirty eight patients were identified with a mean age of 22 years. Essential hypertension was diagnosed in 82% of patients, and 71% of patients had a family history of hypertension. The median systolic blood pressure (BP) at first visit was 132 mmHg and diastolic BP 84mmHg. The median BMI was 25.4 kg/m2 and 68% had some form of target organ damage. Twenty six percent were current smokers and 8% had abused metamphetamines. Recognised secondary causes of hypertension were renal artery stenosis (four) and primary aldosteronism (one).
Conclusions: In a cohort of young hypertensives patients the dominant cause was essential hypertension. Although the prevalence of obesity was surprisingly low compared to previously published studies, significant lifestyle issues were identified. 68% had target organ damage suggesting the disease was not benign. These preliminary results indicate that larger cohorts need to be studied to develop new policies for assessment and treatment of young people with hypertension in South Africa.
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