1. Adherence to Antidepressant Medications Among Health Plan Members Diagnosed with Major Depression Ayse Akincigil, John R. Bowblis, Carrie Levin, James T. Walkup, Saira Jan, Stephen Crystal AcademyHealth 2006 Annual Research Meeting Monday, June 26 Supported in part through NIMH grant R01 MH60831, AHRQ grants U18 HS016097 and HS-01182, and a grant by Horizon BCBSNJ

2. Background / Objectives There is a large amount of evidence that antidepressants are effective in reducing symptoms of depression and preventing relapse; however, poor adherence to medication is a major obstacle to effective care. We describe characteristics of patients at risk for low adherence, and implications for policy and practice.

3. Methods A retrospective, observational study of insurance claims. A retrospective, observational study of insurance claims. A large insurance company in Northeast, serving three- million lives. A large insurance company in Northeast, serving three- million lives. Data are constructed from insurance claims, between January 2003 and January 2005. Data are constructed from insurance claims, between January 2003 and January 2005. Pharmacy claims are used to construct the outcome measure -- refill persistence. Pharmacy claims are used to construct the outcome measure -- refill persistence. Medical claims are used to identify patients with a new episode of depression. Medical claims are used to identify patients with a new episode of depression.

4. Study Population 3014 Prescription look back period 90 days Index prescription date Index episode start date (Date of Depression Diagnosis) Diagnosis look back period 120 days Medication window

5. Outcome Measures 3014 Index prescription date Index episode start date Effective Acute Phase Treatment 114 days Effective Continuation Phase Treatment 231 days

6. Overall Rates of Refill Persistence

7. Demographic, Socio-Economic Characteristics Gender (67% female) Gender (67% female) Age Age 18-25 ( 11% ) 18-25 ( 11% ) 25-39 ( 32% ) 25-39 ( 32% ) 40-49 ( 28% ) 40-49 ( 28% ) 50-64 ( 26% ) 50-64 ( 26% ) 65 or older ( 4% ) 65 or older ( 4% ) Median household income at the neighborhood (zip- code) Median household income at the neighborhood (zip- code) <50k ( 29% ) <50k ( 29% ) 50k-70k ( 42% ) 50k-70k ( 42% ) >70k ( 29% ) >70k ( 29% )

8. Comorbid Conditions Alcohol Abuse (5%) Substance Abuse (8%) Anxiety Disorder (28%) Cancer (18%) Number of Cardiovascular Risk Factors ( 18% suffer from one, 6% suffer from 2 or more)

9. Care Patterns for Depression Episode Type of Provider on Initial Visit (49% were mental health professional, 51% were general medical care). Type of Provider on Initial Visit (49% were mental health professional, 51% were general medical care). Initial antidepressant drug type (4% were on older generation drugs). Initial antidepressant drug type (4% were on older generation drugs). 28% had a follow-up visit with a psychiatrist. 28% had a follow-up visit with a psychiatrist. 24% had a follow-up visit with another mental health provider (e.g., psychologists, social workers). 24% had a follow-up visit with another mental health provider (e.g., psychologists, social workers).

10. General Use of Health and Pharmacy Services

11. Predictors of Refill Persistence in Acute Phase (1)

12. Predictors of Refill Persistence in Acute Phase (2)

13. Predictors of Refill Persistence in Acute Phase (3)

14. Predictors of Refill Persistence in Acute Phase (4)

15. Non-Adherence Risk Factors for 0-8 Months (Continuation Phase) Males * Males * Younger age Younger age Patients from low income neighborhoods Patients from low income neighborhoods Comorbid substance abuse Comorbid substance abuse Comorbid alcohol abuse Comorbid alcohol abuse 2+ CVD 2+ CVD Protective Factors F/U care from a psychiatrist F/U care from a psychiatrist Number of medications other than psychotropics Number of medications other than psychotropics

16. Summary Adherence rates are low, problem worsens in continuation phase. Adherence rates are low, problem worsens in continuation phase. Males, younger, and living in lower income neighborhoods are particularly at risk. Males, younger, and living in lower income neighborhoods are particularly at risk. No support to the scenario of medication crowd-out among users of multiple medications. No support to the scenario of medication crowd-out among users of multiple medications. Presence of multiple cardiovascular risk factors may crowd out depression. Presence of multiple cardiovascular risk factors may crowd out depression. Depression care for those with comorbid substance abuse and alcohol abuse are further complicated due to adherence issues. Depression care for those with comorbid substance abuse and alcohol abuse are further complicated due to adherence issues. Having a follow up with a psychiatrist improves odds of adherence. Having a follow up with a psychiatrist improves odds of adherence. Those who had follow up visits with social workers or psychologists were equally likely to adhere, compared to those with no follow up. Those who had follow up visits with social workers or psychologists were equally likely to adhere, compared to those with no follow up.