Childhood determinants of blood pressure and prehypertension in adolescents - results from the SAPALDIA youth study

Abstract

Background: Hypertension has become the leading risk factor contributing to the global disability adjusted life years. Adolescent hypertension is increasing, possibly due to the obesity epidemic, and is known to track into adulthood. The SAPALDIA Youth Study, a nested study within the adult Swiss Air Pollution And Lung and Heart Disease In Adults cohort (SAPALDIA), aims to investigate early life factors and cardiovascular health in adolescents, with a special focus on active tobacco exposure. Methods: 288 SAPALDIA offspring (mean age 15 years, sd 3.5) underwent clinical examination and reported on early life, health and lifestyle, smoking habits and disease history. Parental determinants and disease status were taken from the SAPALDIA adult cohort data. The mean of two blood pressure measurements, following standard protocols, was calculated for analyses. Prehypertension in childhood was defined as average systolic (SBP) or diastolic blood pressure (DBP) levels ≥90th percentile but <95th percentile for gender, age, and height, respectively in adolescents ≥120/80 mmHg (2). Descriptive and multi-level regression analyses were performed to investigate the independent impact of early life determinants on blood pressure and prehypertension. Results: Prehypertensive values were found in 24%. We confirmed the impact of BMI on SBP (1 mmHg/10 percentile points, 95% CI 0.04,0.14, DBP 0.02 mmHg, 95%Ci -0.02; 0.06), and of high physical activity (≥60 min strenuous activity/day, SBP -3mmHg, 95% CI -6.0; 0.1, DBP -2.2 mmHg, -4.5; 0.1) and found a borderline significance for weekly smoking on SBP (SBP 3.6 mmHg; 95% CI -0.82; 8.0; DBP 2.3 mmHg, 95% CI -1.2; 5.7). Additional adjustment for parental education, smoking and cardiovascular risk strengthened the adverse association seen for weekly smoking. Associations with DBP proved less significant. Similar results were found in analyses with prehypertension. Conclusion: A high percentage of youth presented with prehypertension. Considering the impact of modifiable risk factors, and the high risk of prehypertension turning into clinical hypertension, screening for prehypertension and risk factors in youth should be given full attention to reduce the population risk by optimal metabolic control and lifestyle modification. Reference: 1. National High Blood Pressure Education Program Working Group on High Blood Pressure in Children and Adolescents. The Fourth Report on the Diagnosis, Evaluation, and Treatment of High Blood Pressure in Children and Adolescents. Pediatrics 2004