Hypertension in children from a nephrological perspective — are there any differences between younger children and adolescents?

Background. Hypertension (HTN) affects about 5% of children. Renal diseases are the major cause of HTN in pediatric patients, but the incidence of primary HTN is increasing. The aim of the study was to analyze the potential differences between etiology of HTN, type of renal disease leading to HTN, clinical picture, laboratory test results or family history, with reference to patients’ age. Material and methods. Medical records of 112 patients (27 children < 11 years and 85 adolescents > 11 years), diagnosed with hypertension in the Department of Pediatric Nephrology, were analyzed. Family history, aetiology of HTN, clinical course and laboratory results were compared, regarding the patients’ age. Results. HTN secondary to renal disease prevailed over the primary one in younger children. Major causes of renal HTN differed with age. In children under 11 anomalies in the urinary tract were dominant, in teenagers — glomerulopathies. In adolescents, the incidence of primary HTN was higher than in the younger patients and became comparable to that of secondary HTN. Patients with primary HTN, irrespective of their age, had higher BMI and more frequent positive family history of HTN. Clinical symptoms, except for headaches prevalent in adolescents, did not depend on age. Conclusions. In paediatric patients, hypertension secondary to renal diseases is more frequent than the primary one. The incidence of primary HTN is increasing with age and occurs in adolescents more often than in younger children. The clinical course is usually asymptomatic and may delay the diagnosis, especially in the youngest patients.