More adults have congenital heart disease-study

DALLAS, Jan 9 (Reuters) Severe cases of congenital heart disease are on the rise among North American adults, but researchers say that probably means growing numbers of infants born with the condition are surviving into adulthood.

''This is a real success story,'' said Dr Ariane Marelli, lead author of a new study on the trend and director of the McGill Adult Unit for Congenital Heart Disease Excellence at McGill University in Montreal.

The study, which analyzed databases in the Canadian province of Quebec where access to health care is universal, found that severe congenital heart disease had risen among adults by 85 per cent from 1985 to 2000.

Among children the increase over the same time period was 22 per cent, according to the study which was published on Monday in the Dallas-based magazine Circulation: Journal of the American Heart Association.

Congenital heart defects occur before birth and are structural problems related to the abnormal formation of the heart or major blood vessels near it.

Marelli said increased survival rates for infants born with the defects were the most likely reason for increasing adult prevalence of severe CHD but more research was needed to make the link definitive.

''There are many possible reasons for the increase but we think the most likely reasons are that advances in care of pediatric heart patients have allowed these infants to survive into adulthood,'' she said.

She said infants born with the condition before the 1960s and 1970s were less likely to survive than they are now.

''To our knowledge, this is the first study to measure the changing number of patients in a North American population during a period of major progress in the management of CHD,'' said Marelli.

''This is the largest population study of CHD to have been performed in North America. We have no reason to believe that the predominantly Caucasian population of Quebec and Canada is different from the United States,'' she said.

Extrapolating the study findings in Quebec to the US population, researchers estimate that 1.8 million Americans had the disease in 2000 -- 900,000 adults and 900,000 children.

This points to one of every 85 children having the disease in 2000 and one out of every 250 adults.

''For comparison purposes, cystic fibrosis occurs in one of 4,500 live births, so there are 45 times more children with CHD than children with cystic fibrosis and most of these children are now becoming adults,'' Marelli said.

''The increasing prevalence of CHD means these children will live longer and acquire other forms of heart disease,'' Marelli said.

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