Impact of psychiatric comorbidities on health care utilization and cost of care in multiple myeloma.

Approximately one third of cancer patients suffer from comorbid mood disorders that are associated with increased cost and poorer outcomes. The majority of patients with multiple myeloma (MM) are treated with corticosteroids; as many as three fourths of those taking corticosteroids develop neuropsychiatric complications, likely increasing morbidity and cost of care. MM patients diagnosed between 1991 and 2010 and reported in the Surveillance Epidemiology, and End Results-Medicare database were characterized as MM-Only, MM+Psychiatric (any psychiatric condition, preexisting or post-MM), or MM+Depression (depression as the only psychiatric diagnosis, preexisting or post-MM). Differences in demographic characteristics, occurrence of clinical myeloma-defining events (MDEs), health care utilization (inpatient, outpatient, ambulatory claims), and cost of care during the first 6 months of MM diagnosis were analyzed. Psychiatric comorbidities were reported more frequently in females, and racial minorities had lower rates of psychiatric comorbidities. All clinical MDEs were more common in the MM+Psychiatric and MM+Depression groups; within them, the majority were more common in patients diagnosed with the psychiatric condition or depression after MM compared with it being a preexisting condition. Health care utilization in all treatment settings was higher in those with psychiatric comorbidities. Cost of care within the first 6 months after MM diagnosis was significantly higher in the MM+Psychiatric and MM+Depression groups. This increase in cost was more pronounced for patients from racial minorities diagnosed with a psychiatric condition, including depression. Psychiatric comorbidities significantly impact the clinical presentations, health care utilization, and cost among patients with MM. These findings need to be addressed for improved survivorship of MM patients.