Few Breast-Cancer Patients With HF Referred to Cardiologists, With Implications for Survival

BALTIMORE, MD — Cardiotoxicity is a common side effect of certain breast-cancer treatments, yet only a minority of women who develop cardiovascular problems are promptly seen by cardiologists, a new study shows^[1].

Moreover, women who don't get cardiology follow-up faced a higher one-year mortality, investigators say.

Dr Jersey Chen (Kaiser Permanente, Rockville, MD) presented the analysis earlier this week at the American Heart Association Quality of Care and Outcomes Research 2014 Scientific Sessions .

Chen and colleagues linked Medicare data on women over age 65 diagnosed with stage I to III breast cancer between 2000 and 2009 who also developed heart failure (HF) or cardiomyopathy (CM) with diagnostic billing codes indicating whether the women had seen a cardiologist in the first 90 days of their HF/CM diagnoses. In all, 8400 women with breast cancer were treated with anthracycline drugs or trastuzumab (Herceptin, Genentech), and of these, 1028 (12%) developed HF/CM within three years.

In this group, only one-third saw a cardiologist within three months of their heart-disease diagnosis.

Delving deeper, Chen et al then used Medicare pharmacy claims to see whether women had filled prescriptions for heart meds and linked this to whether or not the women had been seen by a cardiologist.

Not surprisingly, prescriptions for ACE inhibitors and angiotensin-receptor blockers (ARBs) were more common among the women with HF/CM who'd been seen by a cardiologist than among those who had not: 60% vs 44% (p=0.039). A similar pattern was seen for beta-blockers (40% vs 24%, p=0.26).

Strikingly, one-year survival after a HF/CM diagnosis in these breast-cancer survivors was significantly higher among the women who'd been seen by cardiologists than those seen by noncardiologists: 91% vs 79% (p=0.001).

"The majority of women who developed HF/CM after breast-cancer therapy were not treated by a cardiologist and had lower quality of care with higher one-year mortality," investigators observe.

The Elephant in the Room

"The elephant in room is that they're are not being referred to a cardiologist, and I'm not sure why," Chen told heartwire .

"It may be a question of culture," he continued. "There might be oncologists and primary-care physicians who want to take care of the cardiac problems as well. Our paper, however, suggests that there is some value to having a cardiologist involved in that care."

Another possible explanation is patient preferences. "It might be because patients and oncologists are really focused on the cancer, and for some people that might be the right approach. Their focus is on beating cancer and away from the side effects," which they plan to deal with "later."

A third possibility is problems of accessing a specialist—in this case, a cardiologist. "I don't think that's likely," Chen said, given that all of the patients in his study were being treated by oncologists.

Of note, however, is the sizable proportion of women not receiving appropriate medications even when treated by cardiologists.

"Cardiologists do a better job [than noncardiologists], but they are still not perfect," he admitted. Some of that undertreatment may be explained by the fact that the patients are very ill, leaving their physicians worried that they can't tolerate the blood-pressure drops their cardiac medications would entail, and that, too, may be appropriate.

"The ideal isn't that we should look for 100% [drug adherence], from cardiologists or noncardiologists, but it is a signal that cardiologists are perhaps better at sneaking in doses slowly and judging when a patient might tolerate the medication. But we do have to figure out why, even among cardiologists, breast-cancer patients aren't getting these treatments."

Problem Likely to Become More Common

To heartwire , Chen noted that for academic cardiologists and oncologists, this is an area of "tremendous interest," with new cardio-oncology centers opening at major institutions "every week or month."

According to Chen, "these are sprouting up very quickly because the chiefs of the medical departments know that it's going to be an increasing problem in the future, because all of the newer cancer drugs have adverse cardiac consequences—hypertension, heart failure, and cardiomyopathy."

Cardiologists practicing outside of academic centers may be only now becoming aware of the scope of the problem, he said.

Chen reports receiving grants from the American Heart Association. None of the coauthors had conflicts of interest.

Heartwire from Medscape © 2014  Medscape, LLC

Cite this: Few Breast-Cancer Patients With HF Referred to Cardiologists, With Implications for Survival - Medscape - Jun 05, 2014.