Impact of an antidepressant adherence

program in a managed care organization

Kara Zivin Bambauer, PhD

Stephen Soumerai, ScD

Alyce Adams, PhDFang Zhang, PhD

Rick Weisblatt, PhDNeil Minkoff, MD

Andrea Grande, RPhDennis Ross-Degnan,

ScD

Harvard Pilgrim Health Care and Harvard Medical School

Background The burden of depression is substantial

Effective medications are available to treat depression

Non-adherence to antidepressants remains a substantial problem

Harvard Pilgrim Health Care (HPHC) sought to improve quality of care for depression using available electronic data

Objectives

To evaluate the effectiveness of providing faxed feedback to physicians regarding patient refill behavior

Does the proportion of patients who are potentially non-adherent to treatment decrease after the policy?

Does the proportion of days within a treatment episode without antidepressant coverage decrease after the policy?

Content of Fax Introduction: This is a clinical reminder to assist

physicians who are treating patients for Major Depressive Disorder (MDD)

Explanation: There are 3 quality of care measures for depression treatment

Summary: information on antidepressant compliance Symptoms usually remit in 4-6 weeks Therapy should be continued for 6 months Only 40% of patients of patients adhere to

antidepressant treatment

Closing: Your patient (insert name) has gone more than 10 days without antidepressant treatment (medication name, dose, quantity)

Antidepressant Compliance Program (ACP) Definitions

Adherent: antidepressant prescription refilled within 10 days of an expected refill If not, a fax is sent to the prescribing physician

Potentially non-adherent: antidepressant prescription refilled more than 10 days and less than 30 days after an expected refill

Failure: antidepressant prescription not refilled within 30 days of an expected refill

Assumptions Underlying ACP

The prescribing physician receives the fax

The physician makes contact with the patient

A physician-patient conversation occurs that effectively deals with the reasons for patient non-adherence

The patient subsequently refills the antidepressant prescription in a timely manner

Inclusion Criteria All HPHC members were eligible

All types of providers were included

Each patient needed to be enrolled for 6 months before and 6 months after first antidepressant use

Patients were included who used a select subset of antidepressants usually indicated for treatment of depression

New users of antidepressants (no use in previous 100 days)

First episode of antidepressant treatment for each person

Age ≥ 18

Timeline

5/ 15/ 2003 - 5/ 14/ 2004First year of ACP

2/ 15/ 2003 - 5/ 14/ 2003Phase-in period (data excluded from analysis)

5/ 15/ 2002 - 2/ 14/ 2003Pre-ACP period

5/ 15/ 2003ACP begins

Methods

Interrupted time-series (ITS) analysis using SAS PROC AUTOREG

Used to evaluate rates of change in adherence due to the ACP

Look at slope and level changes

ITS is one of the strongest quasi-experimental designs for studying policy changes

Characteristics of Study Participants (N=13,128)

Mean age (sd): 42 (11) Gender: 69% female Policy Variables

Adherent: 18% Potentially non-adherent: 29% Failure: 53%

No significant differences in pre-policy and post-policy patients

0%

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May-02Aug-02 Nov-02 Feb-03 May-03Aug-03 Nov-03 Feb-04 May-04

% w/ gaps & fail model expected

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sPercent of Non-Adherent Patients Who

Proceed to Adherence Failure

Pre-ACP period

First year of ACP

Phase-in period

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May-02Aug-02 Nov-02 Feb-03 May-03Aug-03 Nov-03 Feb-04 May-04

% coverage model expected

Phase-in periodP

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reatm

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ays

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red

Mean Percent of Treatment Days Not Covered

Pre-ACP period

First year of ACP

Limitations and Implications

Electronic reminder systems, while popular, may not improve patient adherence

Success of such interventions requires a complex chain of events to occur

We cannot determine from electronic data whether communication between physicians and patients addresses reasons for patient non-adherence

Stand alone interventions targeting adherence are not successful

Conclusions The ACP was not successful at increasing

antidepressant adherence rates in HPHC members

Additional research should re-examine assumptions underlying the ACP to identify ways to improve future antidepressant adherence interventions

Effectiveness of electronic interventions should be carefully evaluated before widespread implementation