Nearly one-quarter of children and teens who had their blood pressure screened at a primary care appointment showed a reading in the hypertensive range, but less than half of those readings could be confirmed after the blood pressure was repeated, according to a new Kaiser Permanente study released today in The Journal of Clinical Hypertension. The research shows the importance of taking a second blood pressure reading for those ages 3 to 17 years when the first reading is elevated.

"Pediatricians don't diagnose hypertension in children very often, but if it is there, we want to find it," said Robert James Riewerts, MD, regional chief of Pediatrics for the Southern California Permanente Medical Group. "This study is important because it demonstrates the best path to accurately diagnose hypertension in a child or teen.  Taking a second blood pressure reading is something all clinicians must consider when the initial reading is elevated."

Blood pressure in youth varies considerably and can be affected by factors such as a child's anxiety. Also, determining high blood pressure in children or teens is more difficult to do than in adults because what is considered high varies based on age, gender and height.

Since this study was conducted, Kaiser Permanente in Southern California has put alerts on its electronic health records to alert clinicians when a second blood pressure reading is recommended. Also, decision-support tools were added to help clinicians determine when further evaluation is recommended.

Researchers found that for patients ages 3 to 17 years:

• 24.7 percent had at least one blood pressure reading in the hypertensive range.
• Fewer than half of the children who had their blood pressure screened would be correctly classified based solely on their first blood pressure reading of the appointment.
• 2.3 percent of youth have sustained hypertension over time.

"Because an elevated first blood pressure in youth is common, correct identification of truly elevated blood pressure may be a first step to improve the recognition of hypertension in pediatric care," said Corinna Koebnick, PhD, MSc, of the Kaiser Permanente Southern California Department of Research & Evaluation. "If hypertension is missed, children and teens may not receive the counseling they need for lifestyle changes or medication."

This study is based on the Kaiser Permanente Southern California Children's Health Study, which includes all children and adolescents ages 2 to 19 years in Southern California who are Kaiser Permanente members. The cohort follow-up was conducted through passive surveillance of clinical care information using the electronic health record system.

The final cohort of 755,795 youth was followed during a 4-year study period, January 2012 through December 2015.

Dr. Koebnick suggested that instead of calculating the average of blood pressure readings, using the lower blood pressure reading may be more efficient for most clinicians. 

This study adds to previous Kaiser Permanente research aimed at improving hypertension care, including a study that found children who have a first elevated blood pressure at the doctor's office are not likely to receive the recommended follow-up blood-pressure readings. Another study found that expanding blood pressure screenings to non-primary care settings can help identify more adult patients with high blood pressure.

Other authors on the paper include Yasmina D. Mohan, MPH, and Xia Li, MSc, with the Kaiser Permanente Southern California Department of Research & Evaluation in Pasadena, California; Amy H. Porter, MD, Kaiser Permanente Los Angeles Medical Center, Los Angeles; Matthew F. Daley, MD, Kaiser Permanente Institute for Health Research, Denver; Gang Luo, PhD, Department of Biomedical Informatics and Medical Education, University of Washington, Seattle; and Beatriz D. Kuizon, MD, Department of Biomedical Informatics and Medical Education, University of Washington, Seattle.

The study was supported by funds from the Kaiser Permanente Community Benefit Fund and internal operational funding from Kaiser Permanente Southern California.

About the Kaiser Permanente Southern California Department of Research & Evaluation
The Department of Research & Evaluation conducts high-quality, innovative research into disease etiology, prevention, treatment and care delivery. Investigators conduct epidemiologic research, health services research, biostatistics research, and behavioral research as well as clinical trials. Major areas of study include chronic disease, infectious disease, cancer, drug safety and effectiveness, and maternal and child health. Headquartered in Pasadena, California, the department focuses on translating research to practice quickly to benefit the health and lives of Kaiser Permanente Southern California members and the general public. Visit kp.org/research.

About Kaiser Permanente
Kaiser Permanente is committed to helping shape the future of health care. We are recognized as one of America's leading health care providers and not-for-profit health plans. Founded in 1945, Kaiser Permanente has a mission to provide high-quality, affordable health care services and to improve the health of our members and the communities we serve. We currently serve more than 11.7 million members in eight states and the District of Columbia. Care for members and patients is focused on their total health and guided by their personal Permanente Medical Group physicians, specialists and team of caregivers. Our expert and caring medical teams are empowered and supported by industry-leading technology advances and tools for health promotion, disease prevention, state-of-the-art care delivery and world-class chronic disease management. Kaiser Permanente is dedicated to care innovations, clinical research, health education and the support of community health. For more information, go to: kp.org/share.