An Epidemiology Study of Treatment Resistant Depression in the United States (US)

Epidemiology of Treatment Resistant Depression in the US: Analysis of Health Services Databases

The purpose of this study is to describe the epidemiology of Treatment Resistant Depression (TRD) in the US, including the population incidence of TRD, and TRD as a proportion of Pharmacologically Treated Depression (PTD), and stratify the estimates by sex and age group, with separate estimates for the Medicaid population, the Medicare population, and the privately insured population. Anonymized participants data will be used for the analysis.

Inclusion Criteria:

• Have been in the database for the past year (ignoring breaks of < 30 days)
• Have not had, an excluded diagnosis or dispensing of an AD medication during the past year
• Are aged 14 to 60 years (if in the CCAE or MCDC databases), or are aged greater than or equal to (>=) 65 years (if in the MCDR database). Age is defined as age on Jan 1, 2011. The boundary at age 60 for the first two databases is intended to avoid loss to follow-up due to transfer to Medicare at age 65. The boundary at age 65 for the MCDR database reflects the fact that very few people described by that database are aged less than 65

Exclusion Criteria:

- Participants will be excluded when they receive diagnoses Schizophrenia, Bipolar disorder including mania or Dementia