Specific Aim III and IV

Specific Aim IIIA: Compare all-cause RU and costs between Medicare beneficiaries using AAPs and those not using AAPs for off-label treatment of mental health conditions.

Specific Aim IIIB: Compare mental health RU and costs between Medicare beneficiaries using AAPs and those not using AAPs for off-label treatment of mental health conditions.

Specific Aim IVA: Compare all-cause RU and costs between Medicare beneficiaries using AAPs and those not using AAPs for on-label treatment of mental health conditions.

Specific Aim IVB: Compare mental health RU and costs between Medicare beneficiaries using AAPs and those not using AAPs for on-label treatment of mental health conditions.

Study design and index period

For Specific Aims III and IV a retrospective cohort study design was employed using

Medicare 2008-2010 data. For this section of the study January 1, 2009 – December 31, 2009 was

defined as the index period enabling the use of 12 months of baseline and 12 months of follow up

period.

Eligibility criteria

From the random sample of one million beneficiaries only those with fee-for-service

benefit and continuous Medicare enrollment from 2008-2010 across Part A, Part B and Part D

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variables from the MBSF files. Beneficiaries with a “Stand Alone Prescription Drug Plan” with

zero months of HMO coverage were considered to be fee-for-service beneficiaries. To have

continuous enrollment beneficiaries had to have 12 months of Part A, B and D access as denoted

in the A_MO_CNT, B_MO_CNT and PLNCOVMO variables for each year from January 1, 2008

to December 31, 2010.

Population of interest

The population of interest was Medicare beneficiaries 18 years and older with a mental

health condition. Even though Medicare is primarily for patients over 65 years of age, beneficiaries

who are 18 to 64 years of age were also included since severe mental illness is prevalent among

Medicare beneficiaries under 65 years who are entitled to Medicare due to a disability. According

to the Social Security Administration around 37% of all the Medicare disabled beneficiaries have

severe mental disorders (SSA, 2011). The presence of mental health conditions was identified

using one of two methods:

(3) Beneficiaries had to have at least one inpatient or two outpatient mental health claims

between January 1, 2008 and December 31, 2010. Mental health claims were identified

using ICD-9-CM codes. These claims were identified from the principal diagnosis,

admitting diagnosis or any one of the 25 ICD-9-CM variables in the inpatient and

outpatient files. Mental health claims were identified using ICD-9-CM codes 290.xx –

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Table 11: List of ICD-9-CM codes for mental health conditions from inpatient/outpatient files

ICD-9-CM Condition ICD-9-CM Condition

290.xx Dementia 298.xx Non-organic psychoses

291.xx Alcoholic psychoses 299.xx Psychoses with childhood origin

292.xx Drug psychoses 300.xx Anxiety and neurotic disorders

293.xx Transient organic psychoses 301.xx Personality disorders

294.xx Other organic psychoses 302.xx Psychosexual disorders

295.xx Schizophrenia 303.xx – 305.xx

Psychoactive substance abuse disorders 296.0, 296.1, 296.4-296.9 Bipolar disorder 306.xx – 310.xx

Other mental disorders

296.2,

296.3, 311.xx

Depression 312.xx – 316.xx

Other child and adolescent origin mental disorders

297.xx Paranoid states 317.xx – 319.xx

Mental Retardation

(ii) Beneficiaries who were flagged as having specific mental health conditions in the

MBSF Other Chronic Conditions file were also included in the study sample. Medicare uses this

file to flag beneficiaries who have had at least one inpatient or two outpatient claims for a particular

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presented in Table 12. The variables in the Other Chronic Conditions file were reassigned to

different categories of mental health conditions to match the categories described in Table 11.

Table 12: List of mental health conditions identified from Other Chronic Conditions File

Variable (As denoted in Medicare) Condition (Reassigned variable names) Depression; Depressive disorders Depression

Alzheimer’s disease Dementia

Anxiety disorders Neurotic disorders

Autism spectrum disorders Psychoses with childhood origin Bipolar disorder Bipolar disorder

ADHD, conduct disorders; Learning disabilities; Other developmental delays

Other child and adolescent origin mental disorders

Intellectual disabilities Mental retardation Personality disorders Personality disorders Post-traumatic stress disorder Other mental disorders Schizophrenia; Schizophrenia and other

psychotic disorders

Schizophrenia

Study groups

The population of interest was then divided into two groups for each Specific Aim.

Beneficiaries who had a diagnosis of schizophrenia and/or bipolar disorder were categorized as

the on-label cohort. Beneficiaries who did not have claims for schizophrenia and/or bipolar

disorder were categorized as the off-label cohort. The off-label cohort was used in the analysis of

47 Exposure variable

The exposure of interest for Specific Aims III and IV was AAPs use during the index

period. Beneficiaries were considered to be AAPs users if they had at least two claims (>1 day and

< 60 days apart) for the same antipsychotic agent between January 1, 2009 and December 31,

2009. The AAPs of interest were aripiprazole (Abilify), olanzapine (Zyprexa), quetiapine

(Seroquel), risperidone (Risperdal) and ziprasidone (Geodon) and were identified using their

generic names. The off-label cohort and the on-label cohort were further divided based on their

AAPs use. The groups identified were:

Specific Aim 2: Off-label AAPs user and Off-label AAPs non-user

Specific Aim 3: On-label AAPs user and On-label AAPs non-user

Exclusion criteria

Beneficiaries who met the following criteria were excluded from the study.

1) Beneficiaries who had claims for both an off-label and on-label mental health condition

were excluded from the study analysis in order to create two mutually exclusive groups. These

beneficiaries were excluded since there was no conclusive evidence to identify whether or not the

AAPs were being used to treat on-label conditions.

2) Beneficiaries with prescription claims for asenapine (Saphris), lurasidone (Latuda) and

iloperidone (Fanapt) were excluded from the study since these agents received FDA approval

during and not at the beginning of the index period. Similarly beneficiaries with claims for

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these agents received approvals for only one of the two FDA approved conditions (schizophrenia

or bipolar disorder).

3) Among beneficiaries identified as AAPs non-users, those with prescription claims for

AAPs of interest in 2008 were excluded to ensure that the non-users were truly not using AAPs

during the study period.

After the exclusions were applied to the patient population, the final groups were identified for

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Figure 2: Flowchart of inclusions and exclusions from original sample

Fee-for-service beneficiaries (≥18 years) with continuous enrollment in Part A, B, and D with mental health conditions

Exclude beneficiaries with both on-label and off-label mental health conditions

Off-label cohort On-label cohort

Off-label AAPs Users Off-label AAPs Non-Users

On-label AAPs Users On-label AAPs Non-Users

Exclude beneficiaries with claims for newer AAPs

Exclude beneficiaries with claims for AAPs in 2008 among Non-Users

Specific Aim 2: Off-label Users Specific Aim 2: Off-label Non-Users Specific Aim 3: On-label Users Specific Aim 3: On-label Non-Users

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