OBJECTIVES: To examine the association between depression and healthcare costs in medically ill fee-for-service (FFS) Medicare recipients.
STUDY DESIGN: Observational analysis of Medicare claims data.
SETTING: Medicare Health Support (MHS) program at Green Ribbon Health.
PARTICIPANTS: Fourteen thousand nine hundred two participants with diabetes mellitus, congestive heart failure (CHF), or both.
MEASUREMENTS: This study examined participant data for a 12-month period before MHS enrollment (collected between November 2004 and August 2006). Twelve-month healthcare costs (based on Medicare claims) in 2,108 participants with International Classification of Diseases, Ninth Revision, claims diagnoses of depression, 1,081 participants with possible depression (positive depression screen on the two-item Patient Health Questionnaire or self reported antidepressant use), and 11,713 participants without depression were compared. Gamma regression models were used to adjust for demographic and clinical differences and nonnormal distribution of cost data.
RESULTS: Participants with depression had significantly higher total healthcare costs than those without ($20,046 vs $11,956; P<.01). Higher costs were observed in participants with depression in every cost category except specialty mental health care, which accounted for less than 1% of total healthcare costs. Participants with depression had higher costs in each quartile of increasing medical severity (measured using the Charlson Comorbidity Index). These differences remained statistically significant after adjusting for demographic and other clinical differences.
CONCLUSION: Depression is associated with significantly higher healthcare costs in FFS Medicare recipients with diabetes mellitus and CHF. Only a small proportion of the increased costs are spent on mental health specialty care.