Photo by Rhoda Baer
Survivors of Hodgkin lymphoma (HL) have an increased risk of developing cardiovascular diseases throughout their lives, according to a study published in JAMA Internal Medicine.
Previous research suggested that HL treatment is associated with an increased risk of cardiovascular diseases.
However, those studies did not determine how long the increased risk persists or pinpoint the risk factors for various cardiovascular diseases.
So Flora E. van Leeuwen, PhD, of the Netherlands Cancer Institute in Amsterdam, and her colleagues decided to investigate.
The team examined the risk for cardiovascular disease in HL survivors up to 40 years after they received treatment and compared that with the risk for cardiovascular disease in the general population. The researchers also studied treatment-related risk factors.
The study included 2524 Dutch patients who were diagnosed with HL when they were younger than 51 years of age. The patients’ median age was 27.3 years.
The patients were treated from 1965 through 1995 and had survived for at least 5 years after diagnosis. In all, 2052 patients (81.3%) had received mediastinal radiotherapy, and 773 (30.6%) had received chemotherapy containing an anthracycline.
At a median of 20.3 years of follow-up, there were 1713 cardiovascular events in 797 patients (31.6%), and 410 of those patients (51.4%) had experienced 2 events or more.
The most frequently occurring cardiovascular disease was coronary heart disease (CHD), with 401 patients developing it as their first event. This was followed by valvular heart disease (VHD, 374 events) and heart failure (HF, 140 events).
HL survivors had a 3.2-fold increased risk of developing CHD and a 6.8-fold increased risk of developing HF compared to the general population.
HL survivors who had been treated before age 25 had a 4.6-fold to 7.5-fold increased risk of CHD and a 10.9-fold to 40.5-fold increased risk of HF, depending on the age they ultimately attained.
HL survivors treated at 35 to 50 years of age had a 2.0-fold to 2.3-fold increased risk of CHD and a 3.1-fold to 5.2-fold increased risk of HF, depending on their attained age.
The risks of CHD and HF remained significantly increased beyond 35 years after HL treatment. The standardized incidence ratios were 3.9 and 5.8, respectively.
The median times between HL treatment and first cardiovascular disease events were 18 years for CHD, 24 years for VHD, and 19 years for HF.
The cumulative risk of any type of cardiovascular disease was 50% at 40 years after HL diagnosis. For patients who were treated for HL before they were 25, the cumulative risk of developing a cardiovascular disease at 60 years of age or older was 20% for CHD, 31% for VHD, and 11% for HF.
The study also suggested that mediastinal radiotherapy increased the risk of CHD, VHD, and HF. But anthracycline-containing chemotherapy only increased the risk of VHD and HF.
Dr van Leeuwen and her colleagues concluded that both physicians and patients should be aware that HL survivors have a persistently increased risk of developing cardiovascular diseases throughout their lives. The team also believes the results of their study may direct guidelines for follow-up in HL survivors.
A commentary related to this research is available in JAMA Internal Medicine as well.