Adults who developed heart failure after their first MI had an increased risk of cancer compared with those who did not have heart failure, according to a prospective cohort study of Olmsted County, Minnesota, residents.
After adjusting for age, sex and the Charlson comorbidity index, patients with heart failure were 71 percent more likely to develop cancer. The researchers said that heart failure and cancer were independently associated with increased mortality after MI.
Lead researcher Tal Hasin, MD, of Shaare Zedek Medical Center in Jerusalem, Israel, and colleagues published their results online July 12 in Circulation.
The researchers enrolled 1,081 participants who had their first incident MI from November 2002 through December 2010. They excluded adults who had heart failure or cancer before their MI diagnosis. They also did not include nonmelanoma skin cancers when assessing cancers developed during the study.
The mean age of participants was 64 years old, and 60 percent were men. They were followed from their index MI until March 2013 or until they died, whichever occurred first.
After a mean follow-up period of 4.9 years, 21.1 percent of patients developed heart failure and 9.1 percent developed cancer. The median time to heart failure diagnosis was three days.
Patients who developed heart failure were 10 years older than patients without heart failure. They were also more likely to be women and have adverse risk factors and larger infarctions. In addition, they were less likely to receive reperfusion/revascularization and less likely to be treated to aspirin. The groups had a similar rate of treatment with angiotensin blockade, beta-adrenergic blockade and statins.
The median time from MI to cancer diagnosis was 2.8 years. The incidence density rates for cancer were 33.7 per 1,000 person-years for patients with heart failure and 15.6 per 1,000 person-years for patients without heart failure.
The most common types of cancer among patients with heart failure were respiratory (29 percent of cancer diagnoses), digestive (29 percent) and hematologic (14 percent). The most common types of cancer among patients without heart failure were male reproductive (21 percent), respiratory (17 percent), digestive (14 percent) and female breast (11 percent).
The hazard ratio (HR) for cancer associated with heart failure after adjusting for age, sex and Charlson comorbidity index was 2.16, while the HR for mortality associated with cancer after making the same adjustments was 4.90.
The researchers cited a few limitations of the study, including its observational design. They also did not have data on ongoing medical treatment and laboratory results and onlu had echocardiographic data on 70 percent of patients with heart failure.
“Although findings were statistically significant, the small sample size and number of events are a potential limitation, and confirmation with a larger cohort may be warranted,” they wrote.