Risk of family members inheriting cardiomyopathy investigated

1st September 2015

Close relatives of people who die before 60 from cardiomyopathy have a 29-fold increased risk of developing the disease. And if the relative dies before 35, the risk of getting the disease increases 100-fold.

That is the conclusion of a nationwide family study in Denmark involving 3.9million people.

It looked at the actual risks of people under 50 developing cardiomyopathy.

The study, led by Dr Mattis Ranthe, from the Department of Epidemiology Research at the Statens Serum Institute in Copenhagen, said that though the disease’s inheritance patterns were well understood, how the disease clustered in the under 50s in affected families was unclear.

The researchers investigated the data of 3.9 million people born from 1950 to 2008 on the Danish national register. They looked for premature (under 60) deaths from cardiomyopathy or other conditions, and followed family members from 1977 to 2008 looking for a cardiomyopathy diagnosis before 50.

They identified 3,890 cardiomyopathies in 89 million person-years of follow-up.

Premature cardiomyopathy deaths in first and second-degree relatives were associated with 29-fold and six-fold increases in the rate of cardiomyopathy, respectively.

If the first-degree relative died before 35, the rate of cardiomyopathy diagnosis increased 100-fold; given two or more premature deaths in first-degree relatives, the rate increased more than 400-fold.

In contrast, a family history of premature death from other cardiac or non-cardiac conditions increased the rate of cardiomyopathy three-fold at most.

The researchers concluded that a family history of premature cardiomyopathy death was associated with an increase in risk of cardiomyopathy ranging from six-fold to 400-fold, depending on age, kinship, gender and number of affected family members.

They said: “Our general population-based results support recommendations for pre-symptomatic screening of relatives of cardiomyopathy patients.”

cardiomyopathy family tree

Cardiomyopathy is an inherited disease, and each child of an affected parent has a 50:50 chance of inheriting the disease.

References

Risk of Cardiomyopathy in Younger Persons With a Family History of Death From Cardiomyopathy: A Nationwide Family Study in a Cohort of 3.9 Million Persons. Circulation 2015 Aug 14; MF Ranthe, L Carstensen, N Øyen, MK Jensen, A Axelsson, J Wohlfahrt, M Melbye, H Bundgaard, HA Boyd