Causes of secondary hypertension in the young population: A monocentric study

To study the prevalence of different causes of hypertension in young adults referred to a hypertension center in the south west of France.

We conducted a retrospective overview of patients younger than 40years old hospitalized consecutively in the Hypertension department of Toulouse University Hospital between 2012 and 2014. Clinical data about gender, age, anthropomorphic parameters and blood pressure measurement by 24h Ambulatory Blood Pressure Monitoring (ABPM) were recorded. Biological data concerned dosages of kalemia, renin and aldosterone in the supine or after 15min of seating. Recorded radiological examinations were renal artery ultrasound and abdominal CT scan.

One hundred and forty-eight detailed medical records were analyzed, 69 women and 79 men. Among the 69 women, the causes of secondary hypertension were primary aldosteronism (n=7), fibromuscular dysplasia (n=5) and renal disease (n=4). Oral contraceptives were involved in 13 women. In addition, essential hypertension concerned 40 women (58%). Among the 79 men, the causes of secondary hypertension were primary aldosteronism (n=10), fibromuscular dysplasia (n=3), left main renal artery entrapment by a diaphragmatic crura (n=2), renal disease (n=1), pheochromocytoma (n=3) and coarctation of the aorta (n=2). In addition, essential hypertension concerned 58 men (73%).

In our population, the prevalence of secondary hypertension is close to 33% (42% of females and 27% of males), with the following main causes: primary aldosteronism for 11.5%; fibromuscular dysplasia for 5.4%. Oral contraceptives were involved in the hypertension of 19% of the females.