Epidemiology of Treatment Resistant Depression in Taiwan

Study Overview
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Brief Summary
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The purpose of this study is to assess the epidemiology of Treatment Resistant Depression (TRD) in the nationally insured population in Taiwan including incidence, duration of clinical episodes, and prevalence by age and sex.

Detailed Description
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This is a retrospective study of approximately one million subjects randomly selected from an anonymized database National Health Insurance Research Database (NHIRD). Participants aged 18 years or older who have had neither a depression diagnosis nor a dispensing of an antidepressant medication in the last four months of 2004 will enter the study when they receive in 2005 a depression diagnosis and a dispensing of an antidepressant medication within 30 days of each other and will be followed up to 8 years or until they have 4 months with neither a depression diagnosis nor a dispensing of an antidepressant medication. Treatment Resistant Depression (TRD) Incidence, TRD prevalence by age and sex and duration of clinical episodes will be estimated.

Official Title
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Epidemiology of Treatment Resistant Depression in Taiwan

Conditions
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Depressive Disorder, Treatment-Resistant

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Participants who have been continuously enrolled in the insurance plan since January 1, 2004 (ignoring breaks of less than 30 days) and have not received an exclusion diagnosis and during the last 4 months of 2004, a) Have not received a diagnosis of depression and b) Have not received a dispensing of an AD medication Participants with a diagnosis of a depressive disorder including dysthymic disorder (International Classification of Diseases [ICD]-9 codes 296 depression-related, 300.4, 311) and Major Depressive Disorder (ICD-9 296.2, 296.3) will be followed through December 31, 2013 Exclusion Criteria: - Participants who receive following diagnosis will be excluded, a) Mania, b) Schizophrenia (ICD-9 codes 295), c) Bipolar disorder (ICD-9 codes 296 bipolar-related), D) Dementia (ICD-9 codes 290 or 294); Note: Major depressive disorder (MDD) with psychotic behavior (ICD 296.24 for single episode, ICD 296.34 for recurrent episode) is not an exclusion

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Taiwan Participants with Treatment Resistant Depression<br>Taiwan participants with Depression will be followed up to 8 years for incidence and duration of treatment resistant depression. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Incidence Percentage of Participants with Treatment Resistant Depression | The percentage of beneficiaries of Taiwan's health insurance plan who developed treatment resistant depression during 2005 | Approximately 8 Years | 
| Prevalence Percentage of Participants with Treatment Resistant Depression |  | Approximately 8 Years | 
| Duration of an episode of Depression | Time from onset of depression to cessation of depression visits and medications. | Approximately 8 Years | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Healthcare costs | Direct healthcare cost associated with depression treatment will be assessed. | Approximately 8 Years | 
| Number of Participants With Comorbidities |  | Approximately 8 Years | 
| Medications used by Participants with Treatment Resistant Depression |  | Approximately 8 Years | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Treatment Resistant Depression