Cancer survivors have a higher risk of depression within 2 years after the diagnosis, according to a meta-analysis. But is that true of survivors of all types of cancer? In fact, risk is multifactorial because patients, cancers, comorbidities, and impacts of treatments are all different, say researchers who conducted a study to compare the risk of mood disorders longitudinally.
They matched 190,748 survivors with controls from the Taiwan National Health Insurance Research Database. The median follow-up times were 8.13 and 8.49 years, respectively. The 3 most common cancers were breast, colorectal, and head and neck. Surgery alone was the main treatment, followed by combinations of surgery, chemotherapy, and radiation.
Survivors had a significantly higher risk of mood disorders: 8.38 per 1,000 person-years, compared with 7.21 in the control patients. Major depression and depression disorder were the most common subtypes.
However, the risk of mood disorders (1.13-fold) peaked during the year after the index date and declined thereafter. Moreover, 2 and 5 years later, the risk was similar between the 2 groups. And after 5 years, the risk was even lower in the survivor group than in the control group.
The researchers found patients fell into 3 main categories: persistently increasing risk, higher risk in the first few years and after 5 years of follow-up, and higher risk in the first few years but no difference thereafter. Patients with head and neck cancer, nasopharyngeal cancer, and esophageal cancer were in the first group, with distinct longitudinal patterns. Their risk at 5 years was greater than that of the general population.
Being female, aged 40-59 years, having > 2 primary cancers, having ≥ 2 treatment modalities, Charlson comorbidity index scores > 3, higher urbanization level, and lower income levels were independent risk factors for mood disorders.
The researchers say their findings highlight the importance of taking follow-up time, cancer types, and cancer-related treatment into consideration when evaluating mood disorders in cancer survivors. They also emphasize the need for better psychological management not only in the early postdiagnosis years, but in late follow-up for patients with a “persistent” risk.
Huang WK, Juang YY, Chung CC, et al. J Affect Disord. 2018;236:80-87.