Recognition of Depression and Anxiety among Elderly Colorectal Cancer Patients

This study investigated the ICD-9 diagnostic rates of depressive and anxiety disorders, including major depression, neurotic depression, adjustment disorder with depressed mood, depressive disorder NOS (not elsewhere classified), and anxiety states, among elderly Medicare beneficiaries (age ≥ 65) who received a colorectal cancer diagnosis between 1998 and 2002 in U.S. The Seer-Medicare data, representing 14-25% of the U.S. population, was used to examine ICD-9 diagnostic rates of depressive and anxiety disorders among 56,182 colorectal cancer outpatients and 265,382 noncancer outpatients, respectively. The findings show that the ICD-9 diagnoses ranged from 1.5% to 1.8% for depressive disorders and 0.8% to 1.2% for anxiety states in the colorectal cancer outpatients, and from 2% to 2.5% for depressive disorders and 1.1% to 1.5% for anxiety states in the noncancer outpatients over five years. More than 70% of colorectal cancer outpatients with a depressive diagnosis were diagnosed for depressive disorder NOS. The findings suggest that the difficulty in recognizing depressive symptoms in colorectal cancer patients may contribute in part to the low ICD-9 diagnostic rates of depressive disorders. They call for research attention to the investigation of depressive symptoms for improving the recognition and treatment in this patient population.