24-hour BP data may not predict prognosis in children with CKD

Washington, DC --Diagnostic workup for hypertension in children may include wearing a device that monitors blood pressure over 24 hours. Blood pressure load--the proportion of elevated blood pressure readings detected over 24 hours--is used in addition to average blood pressure as part of the criteria for diagnosing hypertension in children. Elevated BP load is part of the criteria for ambulatory hypertension in pediatric guidelines.

The researchers conducted a new study to determine the prevalence of isolated BP load elevation and associated risk with adverse outcomes in children with CKD. They found that BP load does not provide additive value in discriminating outcomes when used independently or in conjunction with mean systolic BP in children with CKD. Results from the study provide insights on evaluating high blood pressure in children. The findings appear in an upcoming issue of CJASN.

 Use of blood pressure load in everyday practice may lead to confusion in scenarios where a child has elevated blood pressure load but normal average blood pressure, however, and it's unclear how a high blood pressure load (with normal average blood pressure) affects long-term health.

To provide insight, Jason Lee, MD (University of California, San Francisco) and his colleagues studied 533 children with chronic kidney disease who underwent 24-hour blood pressure monitoring, along with tests related to kidney and heart health over several years. Based on 24-hour blood pressure data, the team grouped children as having normal blood pressure, high blood pressure load but without high average blood pressure, and high average blood pressure.

One-quarter of the children had a high blood pressure load. Having high blood pressure load by itself was not associated with higher risks of developing kidney failure or a condition called left ventricular hypertrophy which can develop in response to high blood pressure.

"Our data suggest that the proportion of readings on a 24-hour blood pressure test that are high may not provide additional insight beyond the average blood pressure values surrounding a child's risk for developing a cardiac disease or worsening kidney disease," said Dr. Lee. "However, having high average blood pressure on a 24-hour blood pressure test does strongly predict a child's cardiac and kidney disease risk." 

For more details click on the link: http://dx.doi.org/10.2215/CJN.10130819