The impact of updated clinical blood pressure guidelines on hypertension prevalence among children and adolescents.

Background: To date, population estimates of hypertension prevalence among children and adolescents in Canada have been based on clinical guidelines in the National High Blood Pressure Education Program's 2004 Fourth Report on the Diagnosis, Evaluation, and Treatment of High Blood Pressure in Children and Adolescents (NHBPEP 2004). In 2017, the American Academy of Pediatrics published updated guidelines in Clinical Practice Guideline for Screening and Management of High Blood Pressure in Children and Adolescents (AAP 2017), followed by Hypertension Canada in 2020 with its publication of Comprehensive Guidelines for the Prevention, Diagnosis, Risk Assessment, and Treatment of Hypertension in Adults and Children (HC 2020). This study compares national child and adolescent hypertension prevalence estimates based on NHBPEP 2004, AAP 2017 and HC 2020.

Data And Methods: Six cycles of data spanning 2007 to 2019 from the Canadian Health Measures Survey were used to compare blood pressure (BP) categories and the prevalence of hypertension by sex and age group under all sets of guidelines for children and adolescents aged 6 to 17. The impact of applying AAP 2017 across time and selected characteristics, the resulting reclassification into a higher BP category under AAP 2017, and differences in hypertension prevalence resulting from applying HC 2020 versus AAP 2017 were examined.

Results: Prevalence of Stage 1 hypertension was higher among children and adolescents aged 6 to 17 under AAP 2017 and HC 2020 than under NHBPEP 2004. Overall hypertension prevalence was also higher, and obesity was a major factor associated with being reclassified into a higher BP category under AAP 2017.

Interpretation: Implementation of AAP 2017 and HC 2020 is associated with significant changes in the epidemiology of hypertension. Understanding the impact of applying updated clinical guidelines may help inform population surveillance efforts to track hypertension prevalence among Canada's children and adolescents.