Pre-Diagnostic and Cancer-Associated Depression and Anxiety Among Patients with Hematologic Malignancies in the United States

Background: Little is known about mental health disorders among patients with hematologic malignancies. As depression and anxiety substantially impair the quality of life of patients with cancer, the Institute of Medicine recommends diagnosis and management of these disorders as an integral part of cancer care (Cancer Care for the Whole Patient, IOM, 2008). Moreover, it has been suggested that non-White patients are less likely to disclose depression and anxiety to physicians due to concerns about stigma, and that physicians also inadequately screen this population (Bell, Annals FM, 2011). We aimed to characterize the prevalence and sociodemographic predictors of pre-diagnostic and cancer-associated (CA) depression and anxiety among patients with hematologic malignancies in the United States.

Methods: We conducted a retrospective analysis using the Surveillance Epidemiology and End Results (SEER)-Medicare database. Patients ≥ 67 years old diagnosed with a hematologic malignancy (lymphoma, myeloma, leukemia, or myelodysplastic syndromes) between 2000 and 2015 who died prior to December 31, 2016 were eligible for inclusion. We examined prevalence of pre-diagnostic depression or anxiety, defined as having at least one inpatient or two outpatient Medicare claims for depression or anxiety starting from 24 months to 1 month prior to their blood cancer diagnosis. We also examined prevalence of CA-depression or anxiety, defined as at least one inpatient or two outpatient claims for these conditions between 1 month prior to and 3 months after their blood cancer diagnosis. CA-depression or anxiety were mutually exclusive with pre-diagnostic depression or anxiety respectively. We performed univariable analysis to determine sociodemographic and clinical covariates of CA-depression or CA-anxiety. Next, we fit multivariable logistic regression models to characterize factors independently associated with these two outcomes, adjusting for potential confounders: blood cancer type, age, sex, race, marital status, income, education, comorbidity regardless of univariable significance, and additional variables with p<0.05 in univariable analysis.

Results: A total of 64,018 patients were eligible, of which 53.4% had lymphoma, 18.6% myeloma, 18.0% leukemia, and 10.0% myelodysplastic syndromes. Most patients were White (89.6%) and 51.0% were female. Of the entire cohort, 10.6% had pre-diagnostic depression, 4.4% had CA-depression, 7.4% had pre-diagnostic anxiety, and 2.8% had CA-anxiety. Overall, 20.7% of the cohort met our claims-based definition of at least one of these four mental health disorders. In univariable analysis, patients with CA-depression were more likely to have pre-diagnostic anxiety (10.7% vs. 7.3%, p<0.001), have a high comorbidity score (37.5% vs. 31.8%, p<0.001), be female (56.7% vs. 50.6%, p<0.001), and be unmarried (55.3% vs. 52.0%, p=0.001) versus patients without CA-depression. They were also less likely to be non-White (8.8% vs. 10.5%, p=0.005). All associations except marital status remained significant in multivariable analysis (Table 1). In univariable analysis, patients with CA-anxiety were more likely to have pre-diagnostic depression (18.9% vs. 10.4%, p<0.001) and be female (63.2% vs. 50.5%, p<0.001); they were also less likely to be non-White (7.7% vs. 10.5%, p<0.001) compared to patients without CA-anxiety. All associations remained significant in multivariable analysis (Table 2).

Conclusions: In this large cohort of patients with blood cancers, more than one in five individuals struggled with depression or anxiety either before their blood cancer diagnosis or as a new mental health syndrome during the three months afterward. These data suggest a critical need for systematic mental health screening and management for this patient population. Moreover, the fact that patients with pre-diagnostic anxiety or depression were at increased risk of developing CA-depression or anxiety respectively emphasizes the importance of additional psychosocial support for patients with pre-existing mental disorders. Finally, our finding that non-White patients were significantly less likely to develop CA-depression or anxiety is provocative, and suggests that either non-White patients with hematologic malignancies have a lower incidence of these disorders or that the mental health concerns of this population are less likely to be routinely captured.