As if it’s not hard enough to be facing up to a diagnosis of an inherited heart disease, genetic testing itself could be adding to the psychological burden.
Dr Jodie Ingles, a cardiac genetic counsellor at the Royal Prince Alfred Hospital, told CSANZ 2018 there is growing evidence that changes in genetic testing practices are creating more uncertainty than less.
The size of genetic panels has grown but this is mainly associated with more variants of unknown significance, she said.
“The diagnostic yield of identifying a likely pathogenic or pathogenic variant doesn’t change as the panel size increases, so there’s no real increased value from testing more genes.”
“And that’s using a maximum panel of 46 genes – probably considered fairly conservative these days.”
“Essentially what we are doing is gathering evidence to say if a variant is causative then we can push it up into the pathogenic and likely pathogenic categories; if there is enough evidence that a variant is not the cause we can push it down to the benign and likely benign categories and basically everything else remains in the uncertain category.”
Dr Ingles said some patients were being fed back results including uncertain variants that would potentially never have any impact on them at all.
“In any area of medicine, patients really struggle with uncertainty. It’s definitely not unique to genetics. But one of the issues with all of this uncertainty is that there is potential for patients to not understand or not make use of the information.”
Local qualitative research has confirmed high levels of misunderstanding.
“A lot of these patients had really terrible recall of what their result was. They had this idea that their uncertain variant meant they had something worse with their heart and they failed to have any ability to communicate that to the rest of their family members.”
Patients with a diagnosis of an inherited heart disease also had a number of other issues contributing to anxiety, depression or poor quality of life, said Dr Ingles.
“Almost all of our patients who have a diagnosis of an inherited heart disease will have some sort of lifestyle modification such as exclusion from competitive sport.”
“Having an ICD and particularly those patients who are younger and have multiple ICD shocks can be more at risk of anxiety and post-traumatic distress.”
And experiences such as a family history of sudden cardiac death further contribute to levels of stress.
“We’ve done some research to look at the impact on first-degree relatives after the sudden cardiac death of a young person. What we found was that 1 in 2 family members reported clinically significant levels of posttraumatic stress or prolonged grief on average six years after the death.”
“So our recommendation based on that data was that every family should be offered psychological support. And this is what we now routinely do.”
“Clinical psychologists are very important particularly in the area of sudden cardiac death. These are the families that struggle the most,” she said.
“Because of all this, treatment of these patients is best performed in a multidisciplinary setting. The cardiac genetic counsellor can be a key part of this team and a clinical psychologist may be needed especially in the setting of sudden cardiac death.”