Pregnancy-related mortality due to cardiomyopathy: United States, 1991–1997

Abstract

Objective To describe characteristics and risk factors for pregnancy-related deaths due to cardiomyopathy during 1991–1997 and to assess reasons for the increasing trend in reporting of pregnancy-related deaths due to cardiomyopathy from 1979 through 1997. Methods We used data from the Centers for Disease Control (CDC) and Prevention's Pregnancy Mortality Surveillance System to examine pregnancy-related deaths due to cardiomyopathy from 1991 through 1997. The pregnancy-related mortality ratio for cardiomyopathy was defined as the number of pregnancy-related deaths from cardiomyopathy per 100,000 live births. Cardiomyopathy was classified as peripartum cardiomyopathy or cardiomyopathy due to other causes. Results Of the 245 cardiomyopathy deaths that occurred during 1991–1997, 171 (70%) were due to peripartum cardiomyopathy. The cause-specific pregnancy-related mortality ratio was 0.88 per 100,000 live births. Mortality increased as maternal age increased. Black women were 6.4 times as likely to die from cardiomyopathy as white women. Among peripartum cardiomyopathy cases in which the interval from the end of pregnancy was known, 2% died undelivered, 48% died within 42 days of delivery, and 50% died between 43 days and 1 year postpartum. Conclusion Cardiomyopathy accounts for an increasing proportion of reported pregnancy-related deaths, and the more than six-fold excess risk of death from cardiomyopathy among black women is larger than that for any other cause of death. The increased reporting of these deaths might be largely due to improved case ascertainment. Further studies are required to estimate the prevalence of cardiomyopathy and identify modifiable risk factors associated with these deaths and the reasons for this racial disparity.