Longer cardiac screening intervals may be effective, cost-effective in childhood cancer survivors

Less frequent echocardiographic screening of childhood cancer survivors may effectively detect asymptomatic left ventricular dysfunction (ALVD) and may be more cost-effective than screening per the Children's Oncology Group (COG) guidelines, according to 2 new studies published in the May 20 Annals of Internal Medicine.

In the first study, researchers used a Markov model to simulate the life histories of 10 million childhood cancer survivors from 5 years after cancer diagnosis until death for each of the 12 risk profiles outlined in the COG guidelines, taking into account lifetime anthracycline dose, age at cancer diagnosis, and history of chest irradiation. The intervention examined was screening followed by angiotensin-converting enzyme (ACE) inhibitors and beta-blockers after diagnosis of ALVD. Lifetime costs, quality-adjusted life-years (QALYs), and cumulative incidence of heart failure were compared with different screening intervals based on risk profile and no screening.

The researchers found that the incremental cost-effectiveness ratio (ICER) for the COG guidelines versus no screening was $61,500. In addition, screening according to the guidelines extended life expectancy by 6 months, increased QALYs by 1.6 months, and reduced cumulative incidence of heart failure by 18% 30 years after cancer diagnosis. However, screening less frequently was more cost-effective while maintaining 80% of the health benefits seen with guideline-recommended screening, the researchers noted. Although the study extrapolated lifetime non-heart failure mortality and cumulative incidence of heart failure more than 20 years after cancer diagnosis, and although the efficacy of ACE inhibitors and beta-blockers in this population is unknown, the authors concluded that that screening per COG guidelines is cost-effective for reducing heart failure risk in childhood cancer survivors. However, they also concluded that most of the benefits of screening could be maintained at longer intervals while increasing cost-effectiveness.

In the second study, researchers used a simulation model in a hypothetical population of childhood cancer survivors to compare risks for congestive heart failure (CHF), QALYs, and total costs for different screening intervals. Echocardiographic screening intervals were every 1, 2, 5, or 10 years, followed by ACE inhibitor or beta-blocker therapy in patients whose test results were positive. Patients were categorized as high- or low-risk for CHF on the basis of cumulative anthracycline dose.

For 5-year childhood cancer survivors who were 15 years of age, lifetime CHF risk was 18.8% with routine cardiac assessment, with an average age at onset of 58.8 years. Routine echocardiography reduced lifetime CHF risk by 2.3% when performed every 10 years and by 8.7% when performed annually. The ICER was $11,600 per QALY for assessment every 10 years versus no assessment, while assessment every 5 years yielded an ICR of $117,900 per QALY. For more frequent assessment, the ICERs were greater than $165,000 per QALY. Although the researchers noted that effectiveness of treatment was based on data from adults with CHF but no cancer history, they concluded that current recommendations for cardiac assessment appear to reduce CHF incidence but that less frequent assessments may be preferred. A revision of the current COG guidelines may be warranted, the researchers suggested.

The authors of an accompanying editorial noted that the 2 studies found the COG guidelines to be relatively cost-effective and that cardiomyopathy screening improves both the quality and quantity of patients' lives. “The clinician and patient should be assured that screening for ALVD is a valuable undertaking and that state-of-the-art [cost-effectiveness] analyses allow for variation in their choices based on the details of the clinical presentation, patient preference, and local imaging expertise,” the editorialists wrote.

Both ACP Internist and ACP Hospitalist have covered caring for childhood cancer survivors.