Depression is a significant predictor of 5-year survival and recurrence in patients with head and neck cancer, according to a new study published in Pyschosomatic Medicine (doi: 10.1097/PSY.0000000000000256). These findings represent one of the largest studies to report on the impact of depression on cancer survival.
Although depression can have obvious detrimental effects on a person’s quality of life, its impact on cancer patients is more apparent, explained lead author Eileen Shinn, PhD, assistant professor of Behavioral Science at The University of Texas MD Anderson Cancer Center, in Houston. Increasing evidence shows modest associations between elevated symptoms of depression and greater risk for mortality among patients with lung, breast, ovarian, and kidney cancers.
The research team sought to clarify the influence of depression on survival, focusing their analysis on a single cancer type. By limiting the sample set and adjusting for factors known to affect outcome, such as age, tumor size, and previous chemotherapy, they were able to uncover a more profound impact of depression.
The researchers followed 130 patients at MD Anderson with newly diagnosed oropharyngeal squamous cell carcinoma (OSCC), a type of cancer in which the tumor originates at the back of the throat and base of the tongue.
At the beginning of their radiation therapy, Patients completed a validated questionnaire at the beginning of their radiation therapy to identify symptoms of clinical depression. Researchers monitored the participants, all of whom completed treatment, until their last clinic visit or death, a median period of 5 years.
“The results of this study were quite intriguing, showing depression was a significant factor predicting survival at 5 years, even after controlling for commonly accepted prognostic factors,” said senior author Adam Garden, MD, professor, Radiation Oncology. Furthermore, depression was the only factor shown to have a significant impact on survival.
Patients who scored as depressed on the questionnaire were 3.5 times less likely to have survived to the 5-year interval compared with those who did not score as depressed. The degree of depression was also found to be significant, as every unit increase on this scale indicated a 10% higher risk for reduced survival.
The results were replicated with a different psychological health survey and were not influenced by how soon following diagnosis the depression assessment was done.
OSCC is diagnosed in 10 000 to 15 000 Americans each year. Major risk factors known to be associated with OSCC include smoking and tobacco use, alcohol consumption, and human papillomavirus (HPV) infection. Incidence of OSCC has doubled in the last 20 years due to increasing HPV infection rates, noted Shinn.
Neither alcohol nor tobacco use, also surveyed in this group, had a significant impact on survival. HPV infection status, when available, also did not appear correlated.
Despite a high cure rate, normally 60% to 80%, recurrence rate of disease is unusually high in these patients (approximately 30%). The researchers also investigated a potential link between depression and disease recurrence.
“When we controlled for all variables, depression was linked with a nearly 4 times higher risk of recurrence,” said Shinn. In addition, never smokers had a 73% lower chance of recurrence, compared with current smokers. Those were the only two factors associated with cancer recurrence.