Schema-Focused Therapy for Chronic Depression: Efficacy and Mechanisms of Change

Chronic major depressive disorder (MDD) is a relatively common mental illness
that represents a significant burden on the health care system. Compared to
episodic forms of depression, chronic MDD is associated with higher economic
costs, has a stronger impact on the quality of life, and results in more
suicide attempts.
Response rates to available treatments for chronic forms of depression are low
and effects of treatment attempts are only maintained as long as treatment is
continued. One reason for this might be that current treatments for chronic
depression leave the underlying vulnerability to depression largely untouched.
In this light we propose schema-focused therapy (SFT) as a novel treatment
approach to chronic MDD.

Our primary aim is to test whether SFT is a suitable and effective treatment
for chronic depression in terms of acute effects and the prevention of early
relapse.
Our secondary aim is to identify the underlying mechanisms of change in SFT
that lead to recovery from depression and the prevention of future relapse.

The present study is an intervention study with multiple baselines and
measurement occasions. We implemented a non-concurrent single-case series A-B-C
design with multiple quasi-randomized baselines across participants and 12
months follow-up. Phase A in this study is a baseline phase with a minimum
duration of 6 weeks and probably longer, depending on the waiting time at the
Riagg Maastricht. Phase B is a 12 week exploration phase during which the
case-conceptualization will be done and treatment goals will be set. Phase C is
the intervention phase wherein patients will receive SFT during a period of
approximately 18 months. In total this study will last between 2 and 3 years
for each individual participant, depending on the individual progress in
therapy.

All patients in this study will receive 25 to 75 once weekly sessions SFT over
the course of 18 months, depending on the individual progress in therapy. SFT
is a novel treatment approach to chronic, lifelong problems that incorporates
cognitive, behavioral, experiential and psychodynamic elements and techniques.

Participants in this study will be asked to regularly complete a number of
questionnaires, complete a clinical interview at three moments in time, and to
complete a small computer task five times. Completion of the weekly
questionnaires will take about 5-10 minutes per week and completion of the
monthly questionnaires about 1 1/2 hours per month. The computer task will take
about 20 minutes to complete and the clinical interview between 1 and 2 hours.
Questionnaires will be obtained regularly during the baseline phase A, the
exploration phase B and the intervention phase C. During follow-up the most
important outcome measures will be obtained on a monthly basis which will take
about 5-10 minutes per month. At 12 months follow-up participants will be asked
to visit the Riagg Maastricht once in order to complete the clinical interview
which will take between 1 and 2 hours.
Participants will also be asked to complete a self-reflection task while
undergoing functional magnetic resonance imaging (fMRI) at two time points. The
first fMRI session will be conducted before the start of the intervention and
the second fMRI session at the end of the intervention phase. Each session will
take about 45 minutes to complete. During both sessions participants will be
asked to complete a short self-reflection task. During the second a mood
induction procedure will be used in addition to the self-reflection task. This
standardized procedure will consist of mood suggestive music in combination
with autobiographical recall (10 minutes).