Pregnancy in survivors of childhood cancer may confer elevated risk for cardiotoxicity
Pregnancy may be linked to an increased risk for cardiotoxicity in patients who survived cancer in childhood, according to a research letter published in the Journal of the American College of Cardiology.
Using data from The University of Texas MD Anderson Cancer Center, Kara A. Thompson, MD, from the department of cardiology at the University of Texas, Houston, and colleagues evaluated the cardiac outcomes of childhood cancer survivors who were pregnant and who were previously exposed to anthracyclines and/or chest radiation.
A total of 337 women aged 16 to 55 years and who had been diagnosed with cancer at age younger than 20 years and treated with anthracyclines and/or chest radiation were identified by the researchers. Patients were followed up for at least 10 years from the time of diagnosis unless pregnancy occurred before 10 years; median follow-up was 20 years.
Every 1 to 5 years, echocardiographic screenings were conducted, as recommended by the risk-based Children’s Oncology Group survivorship guidelines.
The researchers compared 58 women who had at least one pregnancy with 80 women who had similar anthracycline doses and follow-up times.
In the control group, 15% (n = 12) had an adverse cardiac event, defined as ejection fraction < 50% on at least two echocardiograms or CAD.
Of those who had at least one pregnancy, 29.3% (n = 17) had adverse cardiac events. Three were diagnosed with cardiac disease before pregnancy, nine during pregnancy and five post-pregnancy.
Of the17 patients who had at least one pregnancy experienced adverse cardiac events, at the time of last follow-up, 47.1% had recovered, 41.2% had not recovered and 11.8% had died.
According to the researchers, there was a 14% reduction in risk (OR = 0.86; 95% CI, 0.76-0.97) in older patients at the time of cancer diagnosis.
Longer time to first pregnancy was linked to a significant risk increase (OR = 1.13; 95% CI, 1.03-1.25), meaning that increased length of time between exposure to anthracyclines and time to first pregnancy may increase risk for cardiotoxicity, according to the researchers.
Additionally, higher anthracycline dose was associated with an increase in risk (OR = 1.01; 95% CI, 1-1.01).
In the overall cohort (n = 138), pregnancy was associated with a 2.35-fold increase in risk for cardiotoxicity (95% CI, 1.02-5.41). When adjusted for anthracycline dose, this effect increased in significance (OR = 2.8; 95% CI, 1.14-6.86) and remained borderline significant after adjustment for follow-up time (OR = 2.48; 95% CI, 0.995-6.22).
“In our study of high-risk pregnant patients, we identified subgroups with an increased risk of adverse cardiac outcomes: younger age at cancer diagnosis, longer time from cancer treatment to first pregnancy, and higher total anthracycline dose,” Thompson and colleagues wrote. “Pregnancy was an independent risk for cardiotoxicity. These patients require more vigilant monitoring than the general population.” – by Dave Quaile
Disclosure: The researchers report no relevant financial disclosures.