“Unfortunately, among patients with breast cancer, healthy survivorship can be impacted by late side effects to treatment and the cancer itself, especially cardiovascular side effects,” says Maria D’Souza, MD. For a study published in Heart Rhythm, Dr. D’Souza, and colleagues sought to estimate the long-term incidence of new-onset atrial fibrillation (AF) in patients with recently diagnosed breast cancer compared with that of the general population.

The researchers assess patients diagnosed with breast cancer from 1998 to 2015 in nation-wide registries and age-matched controls (1:3) from the general population. They found breast cancer to be associated with incident AF, with the association differing between age groups and follow-up time periods. “We found that patients with breast cancer have a higher risk of developing AF than the general population up to 3 years following their diagnosis,” says Dr. D’Souza. “The risk was relatively higher in the youngest patients (< 60 years) compared with the general population, but the oldest patients (>60 years) had the highest absolute risk.”

Dr. D’Souza notes that because the study was observational, her research team can only speak of associations and not causality. “The study should prompt awareness of the higher AF risk following breast cancer,” she adds. “However, our results do not imply any specific or systematic initiatives in the clinic. We need more knowledge to decide on the appropriate initiatives, if any.”