While pulmonary hypertension (PH) is a relatively rare problem in pediatrics, the frequency of the diagnosis and PH-related hospitalizations are rising. PH complicates a number of different disease processes, including congenital heart disease, chronic lung disease of prematurity, and genetic disorders. In other cases, the cause of PH may be unknown.
“Without being melodramatic, pulmonary hypertension is a massive problem in the U.S.,” said Brian Hanna, MDCM, PhD, director of the pulmonary hypertension program at The Children’s Hospital of Philadelphia that follows more 650 children and adolescents with PH. “It consumes a huge amount of resources, not just hospital beds. We consult with virtually every service in the hospital — catheterizations, echocardiograms, laboratories, pharmacy, and others.”
Pulmonary hypertension occurs when the arteries of the lungs (the pulmonary arteries) have high blood pressure. Over time, the pulmonary arteries narrow, making the right side of the heart work harder. While researchers have come a long way in the past few decades in terms of understanding the disease, there is no cure or FDA-approved therapies for pediatric PH.
“We still have more questions than answers,” said Rachel Hopper, MD an attending cardiologist in pulmonary hypertension at the CHOP Cardiac Center and assistant professor of pediatrics at the Perelman School of Medicine at the University of Pennsylvania. “Who gets pulmonary hypertension? Why do they get pulmonary hypertension? Why do some children with hypertension improve over time, while others will end up needing a lung transplant? We need to collaborate as practitioners to pool enough data to answer those questions.”
That is why Dr. Hanna and Dr. Hopper are excited that The National Heart, Lung, and Blood Institute recently awarded a grant to support the nine pediatric centers, including CHOP, that are members of the Pediatric Pulmonary Hypertension Network (PPHNet) in their efforts to build an informatics registry.
For research purposes, a registry provides a shared infrastructure and standardized data collection in a single resource so that investigators can evaluate specific outcomes for a group of patients who share the same condition. For example, the PPHNet registry could help researchers determine the response of children with PH to certain therapies. On its own, an individual pediatric PH center would not be able to gather this information for a large enough number of children with PH.
Traditionally, registries are expensive to run because they require diligent maintenance to ensure that the data is precisely collected and valid for research. A unique feature of the PPHNet project is that it aims to determine if it is possible to obtain the same type of data using computer software to crawl through electronic health records (EHRs). The researchers will compare the value of both methods and determine if the data generated produce the same results upon analysis during an observational study.
As they figure out the most efficient and accurate way to collect and store registry information about children with PH, the researchers also hope to gain important insights into the causes, clinical course, and diagnostic approaches to the diverse conditions associated with PH that will lead to better treatment.
Unfortunately, many of the current care practices for children with PH are based on findings from adult studies, Dr. Hanna pointed out. Clinicians do not know, for instance, if a 13-year-old who has PH on a genetic basis and starts medicines earlier than a 35-year-old with the exact same genetic mutation will have a longer, better life.
“The concept of pooling and precisely phenotyping children is going to make a huge difference,” said Dr. Hanna, who is also a clinical professor of pediatrics for the Perelman School of Medicine at the University of Pennsylvania. “A key thing is that we eventually will be able to make diagnoses and conduct research protocols all the same way. We’ll be able to advance the science faster and understand it better, so that we’ll be to answer questions about pediatric pulmonary hypertension.”