Researchers at Geisinger discovered that genomic screening can help identify patients who are at risk for heart disease associated with amyloidosis, the build-up of abnormal proteins in the organs and tissues.
Transthyretin amyloidosis (ATTR) can be hereditary and lead to a spectrum of other diseases and conditions, including cardiomyopathy, a common precursor to heart failure. One known cause of ATTR is variation of the transthyretin (TTR) gene, so researchers hypothesized that identification of disease-causing variants could lead to discovery of undiagnosed disease.
New treatments for ATTR have improved survival rates, but diagnosis based on symptoms is challenging. Using data from the MyCode Community Health Initiative, which analyzes the DNA of consented participants to study a broad range of health and disease, and electronic health records, researchers studied patients with and without specific TTR variants to determine how often they showed signs of cardiomyopathy and compared those results to findings from cardiac imaging.
They identified 157 patients who carried a known disease-causing TTR variant among the 134,753 patients studied. Related heart-disease diagnoses, including cardiomyopathy and heart failure, were significantly more likely in those 60 and older, but only two of the 157 patients identified already had a clinical diagnosis of amyloidosis.
“We not only found that patients with variants identified by genomic screening had increased risk of heart disease after age 60 but also that the amyloidosis causing that heart disease is likely going to be undiagnosed without knowledge of the genetic variant,” says Brendan Carry, MD, Geisinger cardiologist and one of the study’s lead authors. Carry co-leads the Geisinger multidisciplinary amyloidosis clinic with neurologist colleague David Avila, MD.
The research has positive implications for the future of population health as well as treatment of amyloid cardiomyopathy, heart failure, and other amyloid-related conditions.
“Historically, hereditary amyloidosis has been underdiagnosed, which can be a burden on families for generations,” says Christopher Haggerty, PhD, associate professor in translational data science and informatics at Geisinger and the senior author of the study. “A genetic-screening approach to identifying TTR gene variants has the potential to diagnose previously unrecognized cases of ATTR and identify patients at risk for developing cardiomyopathy and other diseases. If we can identify this risk earlier in a patient’s life, we’ll have opportunities to improve treatment.”
The full study can be read in the Journal of the American College of Cardiology: CardioOncology.