The rate of congenital heart disease (CHD) mortality has declined between 1999 and 2006; however, disparities between race and ethnicities still exist, according to a study published online Nov. 22 in Circulation.

“Among infants and young children, congenital heart disease is responsible for the largest proportion, 30 percent to 50 percent, of mortality caused by birth defects,” the authors wrote. However, the authors noted that “survival analyses based on birth defects surveillance system records linked to data from death certificates have been useful in understanding infant and child mortality, but generally have not examined mortality into adulthood or trends in CHD related mortality over time.”

Suzanne M. Gilboa, PhD, of the National Center on Birth Defects and Developmental Disabilities, Centers for Disease Control and Prevention in Atlanta, and colleagues sought to bolster evidence-based trends and patterns of CHD-related mortality by using death certificates filed in the U.S. between 1999 and 2006 to evaluate rates of mortality by age, race and ethnicity and sex.

Between 1999 and 2006 there were 41,494 deaths linked to CHD, in addition to 27,960 deaths resulting from CHD. The age-standardized mortality rates were 1.78 and 1.20 per 100,000 deaths, respectively.

Mortality that resulted from CHD declined by 24.1 percent overall, but also declined among all the race and ethnic groups evaluated. However, the researchers found disparities among the various races and ethnicities regarding mortality and found that  CHD-related mortality rates were higher among non-Hispanic blacks when compared to non-Hispanic whites.

Gilboa et al reported that infant mortality accounted for 48.1 percent of all mortality resulting from CHD, but among those who survived the first year of life, 76.1 percent of the deaths occurred in patients who were over the age of 18.

As for age-specific mortality, CHD mortality was highest among infants, lowest among children aged 5 to 17 and increased by 34 percent among adults aged 18 to 34 when compared to children who were aged 5 to 17.

Infant mortality caused by CHD decreased by 17.3 percent overall and decreased among non-Hispanic whites and Hispanics. The researchers noted that non-Hispanic blacks had higher rates of CHD-related mortality when compared to non-Hispanic whites.

For children aged 1 to 4, mortality caused by CHD decreased 21 percent, and 36.1 percent for those aged 5 to 17. For adults aged 35 to 49, adults aged 50 to 64 and those over 65, CHD-related mortality decreased by 24.6 percent, 27.7 percent and 42.7 percent, respectively.

“Less severe CHD that does not cause early mortality (but may be responsible for later mortality) may be diagnosed less frequently in [non-Hispanic] blacks (or Hispanics) than [non-Hispanic] whites,” the authors wrote. “This might ultimately be reflected in differential misclassification of [underlying cause of death] by race-ethnicity.

“The overall reduction in mortality resulting from CHD likely resulted from improved diagnostic capacities, surgical techniques and catheter-based treatments,” the authors noted. “There is debate as to whether prenatal diagnosis of CHD improves survival.”

For CHD-related mortality rates to further decline, the authors suggested that physicians must work on the diagnosis and management of renal impairment and abnormal glucose metabolism and work to educate patients on contraception and pregnancy, genetic transmission of CHD, diet, weight and exercise and physician activity.