CVD Risk Factors Identified in Male Thyroid Cancer Survivors

June 20, 2018

In the Utah Cancer Survivors Study, male thyroid cancer survivors had an almost 50% higher risk of developing cardiovascular disease than females.

Male thyroid cancer survivors may have a nearly 50% higher risk of developing cardiovascular (CVD) disease than women within 5 years of cancer diagnosis, according to Utah researchers. They reported in The Journal of Clinical Endocrinology & Metabolism that some thyroid cancer patients may be at greater risk for CVD, and they advise evaluating and monitoring survivors for specific factors that may elevate risk.

Undergoing thyroid-stimulating hormone (TSH) suppression therapy, having distant metastases at cancer diagnosis, and having a higher Charlson Comorbidity Index (CCI) score all may be associated with an increased CVD risk among thyroid cancer survivors, the investigators found.

“We observed that male thyroid cancer survivors have an almost 50% higher risk of developing cardiovascular disease than females, and obese thyroid cancer survivors have a 41% higher risk. Thyroid-stimulating hormone or TSH suppression therapy was also associated with a 25% higher risk of cardiovascular disease,” said lead author Jihye Park, MSPH, from Huntsman Cancer Institute, Salt Lake City, Utah.

Park and her colleagues used the statewide Utah Population Database to investigate the association between potential risk factors, treatment effects, and CVD outcomes in thyroid cancer survivors. They note that while thyroid cancer survivors are known to be at high risk of developing a variety of cardiac and vascular conditions, there have been few published studies examining what baseline characteristics may predispose this group to such complications.

The researchers identified 3,822 primary thyroid cancer survivors who were diagnosed between 1997 and 2012. They examined the medical records of these patients to investigate risk factors and CVD outcomes. Using Cox proportional hazards models, they found that a patient’s age and year at cancer diagnosis, cancer stage, and sex were significantly associated with CVD risk 1 to 5 years after a thyroid cancer diagnosis.

They also discovered that baseline body mass index (BMI), baseline comorbidities, and TSH suppression therapy were significantly associated with CVD risk 1 to 5 years after cancer diagnosis.

The study demonstrated that patients who were male, overweight or obese, older at cancer diagnosis, and diagnosed with cancer since 2005 had an increased risk of CVD compared with patients who were female, had a normal BMI, were younger at cancer diagnosis, and were diagnosed with cancer between 1997 and 1999.

“Patients who received radiation therapy following surgery also had a higher risk of developing cerebrovascular disease compared to patients who received surgery only. We hope our results help patients and clinicians identify high-risk individuals among thyroid cancer survivors with respect to cardiovascular disease. We also hope these high-risk individuals can be monitored and screened for cardiovascular disease, for both earlier detection and better preventive care,” Park told Cancer Network.

Park said cancer survivors today are living longer, and so they need to be aware of long-term risks of CVD that can result from their cancer treatment and lifestyle factors. She emphasized that thyroid cancer survivors are a specific group that clinicians are concerned about regarding long-term consequences, since thyroid cancer is often diagnosed in young people and in the US the 5-year survival rate is 98%.