Recent Advances in Pediatric Hypertension

Abstract

It has been a long-standing theory that hypertension has its origins in the young. The theory on childhood origins of hypertension has been supported by a substantial body of epidemiologic data that link certain risk factors in childhood such as higher blood pressure (BP) level, obesity, and family history of hypertension with earlier onset of hypertension in adulthood. Evidence developed in recent decades demonstrates that BP levels in childhood are not limited to an estimate of future hypertension. Primary hypertension, as well as secondary hypertension, can be detected in childhood. Based on different but quite conservative diagnostic criteria, the current prevalence of primary hypertension in childhood is approximately 3% to 5%. Hypertension is not only a common childhood disorder, but primary hypertension in childhood has characteristics that are surprisingly similar to hypertension in adulthood, including associated risk factors and evidence of target organ damage. Over the past decade, considerable progress has been made in understanding the childhood phase of primary hypertension. This issue provides a collection of State-of-the-Art reviews on topics that represent significant recent advances in childhood hypertension. Two reviews examine seminal mechanisms, beginning early in human development, that potentially contribute to hypertension. The review by Ingelfinger and Nuyt examines current data related to the ‘‘birth weight hypothesis’’—that alterations in the intrauterine environment resulting in low birth weight program the individual for future cardiovascular and metabolic disorders. The authors provide a focused review on plausible mechanisms including environmental and epigenetic forces that may interact in fetal and perinatal development periods with potential longstanding cardiovascular and renal consequences. Another review by Dr Feig examines a 21st century view on a very old concept—the role of uric acid in the pathogenesis of hypertension. Recent clinical as well as experimental studies show a renewed pathogenic role of uric acid metabolism in the early phase of primary hypertension especially among children with associated obesity. As in adults, ‘‘prehypertension’’ in children is now regarded as a BP risk category that warrants counseling on healthy lifestyles and BP monitoring. The extent of the risk for progression to hypertension has been uncertain due to limited longitudinal data. The authors Redwine and Daniels provide a review of prehypertension in childhood including current data on progression to clinical hypertension, associated risk factors, and detectable target organ damage. The evidence provided in the review indicate that prehypertension is not an entirely benign condition and raises the question as to whether the 95th-percentile criteria for hypertension in children sufficiently captures current and subsequent cardiovascular disease risk. While hypertension-related events are uncommon in children with hypertension, intermediate markers of target organ damage are detectable in hypertensive children. Left ventricular hypertrophy, ascertained by echocardiography, is not uncommon among asymptomatic children with hypertension. In another topic on hypertension-related injury, Dr Lande examines neurocognitive alterations in children with hypertension. In this review, the emerging evidence examined demonstrates that neurocognitive alterations associated with hypertension are not limited to older hypertensive adults, but can be manifested in hypertensive children as well. As data evolve on this issue, there is likely to be a substantial shift in approach to target organ damage associated with childhood hypertension. Primary hypertension in childhood is characterized by variability in BP levels that are measured at different times. It is in part due to the BP variability that multiple BP measurements 95th percentile are required to confirm a diagnosis of hypertension in asymptomatic children. Ambulatory BP monitoring (ABPM) has been useful to identify children with white-coat hypertension; however, ABPM has greater application. As reviewed by Flynn and Urbina, ABPM can be a powerful tool in both the evaluation and management of children with high BP and hypertension. The authors provide detailed guidelines on application and interpretation of ABPM that will be useful to clinicians who care for children with hypertension, chronic kidney disease, diabetes, and other chronic conditions in which optimizing BP control is an important aspect of clinical care. A significant achievement has been the progress in pharmacologic treatment of hypertension in children. Dr Blowey provides a review on advancement in clinical trial studies designed to obtain safety and efficacy data on antihypertensive drugs. With the availability of objective evidence on blood pressure-lowering effects and safety on antihypertensive drugs, informed treatment choices can be made in management of hypertensive children. The final contribution to this issue is an original paper in which the authors make an effort to determine what drugs are being used to treat children with a recorded diagnosis of hypertension. This report provides a glimpse into the real world of contemporary medicine and represents a reminder that despite considerable progress, there is much yet to be done in the childhood phase of hypertension. From the Department of Medicine and Pediatrics, Thomas Jefferson University, Philadelphia, PA