Reducing relapse and recurrence in depression with continuation Cognitive Therapy: a randomized controlled trial.

Major depressive disorder (MDD) is one of the most prevalent of the psychiatric
disorders and is projected to rank second on a list of 15 major diseases in
terms of burden in 2030. The major contribution of MDD to disability and health
care costs is largely due to its highly recurrent nature. Acute phase treatment
with Cognitive Therapy (A-CT) is a well-studied and evidence-based
psychological intervention (e.g. Beck, 2005; Vittengl ea., 2007). Although
two-thirths of all patients respond to A-CT, a sizable number will experience a
return of symptoms after treatment (Fava et al., 2004; Driessen & Hollon 2011).
Reported relapse and recurrence rates for high risk groups rise up to 60-70%
recurrence over 2 year (Vittengl et al., 2007; Bockting et al., 2009). Apart
from the number of previous episodes, residual symptoms are risk factors for
recurrence
(Fava et al., 2004; Judd et al., 1998).

Optimizing long term outcomes is thus an important goal in the treatment of
MDD, especially for well known high risk groups, i.e. patients with multiple
previous episodes and/or residual symptoms. Providing Continuation Preventive
Cognitive Therapy (C-PCT) seems promising, especially in high recurrence risk
patients (for a meta analysis Vittengl et al., 2007; Jarrett et al., 2001).

Previous studies indicated that responders to A-CT already have a reduced
relapse/recurrence risk compared with other forms of acute phase depression
treatments (Vittengl et al. 2007). Therefore the objective of this study is to
examine the surplus value of C-PCT on relapse/recurrence for patients who
responded to A-CT.

The main objective of our study is to evaluate in a randomized clinical trial
the long-term clinical effectiveness of brief C-PCT in high risk recurrently
depressed patients (responding to A-CT), compared with care-as-usual
(monitoring). High risk patients (two or more MDD episodes and a HRSD<14) will
be allocated at random to either care-as-usual or brief C-PCT. The intervention
will last 8 sessions in 12 weeks. Assessment of outcome variables will be
performed at the start of the intervention and 3, 6, 12, 15 months later. The
primary objective of this study is to evaluate in a randomized controlled
clinical trial the long-term clinical effectiveness of brief C-PCT on
relapse/recurrence over 15 months, in high risk recurrently depressed patients
(responding to A-CT), compared with care-as-usual (monitoring). Baed on
previous studies we hypothesize that C-PCT will reduce the change of relapse/
recurrence 20%, during a follow up period of 15 months. The primary outcome
measure is the cumulative proportion of relapses/recurrences in a
survival-analysis over a follow-up period of 15 months after the start of the
preventive therapy. Secundairy objectives are to determine mediators,
moderators and a cost effectiveness evaluation.

Secondary objectives of this study are:
1. The effect of C-PCT on the severity of depressive symptoms, quality of life,
social and interpersonal functioning, coping style.
2. Identification of moderating effects of experienced negative life events,
personality disorder symptomatology, psychological mindfulness, mastery.
3. Identification of mediating effects of coping style, social support,
acceptance and action, outcome, alliance with the therapist, depressive
symptoms, working alliance, dysfunctional attitudes, need for affiliation,
daily stressors, positive and negative affects.
4. Cost effectiveness of C-PCT compared with CAU.

Patients who during the acute phase of their last episode received CT at the
Arkin Mental Health Care Institute of GGZ Ingeest wil be recruited. Patients
who give informed consent will be randomly allocated to a control condition or
an experimental condition. Patients in the control condition receive care as
usual (CAU). CAU consists of the usual care that patients receive in primary
care (and partially in secondary care) after treatment for acute depression.
CAU typically consists of anti-depressant maintenance medication, or no
treatment at all. CAU is in most cases provided by the general practitioner.
Patients in the experimental condition receive, in addition to care as usual, 8
sessions of C-PCT. At baseline and 3, 6, 12 and 15 months measurements will be
performed to evaluate the effectiveness of C-PCT in comparison to care as
usual. After each C-PCT session a short questionnaire will be assessed in order
te study working mechanisms (mediators) of C-PCT.

The time-Schedule of this study is; recruitement: months 1-36, C-PCT
intervention: months 2-39, follow-up assessments: months 2-51, data-analyse en
reporting: months 52-54.

Short-term continuation PCT (C-PCT) consist of 8 sessions that is offered as
sequential treatment after response to A-CT. CT is directed at the
identification of maladaptive cognitions and the development of a personal
prevention strategy. C-PCT (Bockting et al., 2009) is an adapted type of
cognitive therapy specifically developed to prevent relapse in recurrent
depression and adapted to remitted patients. A specific manual for the client
and therapist has been published describing the structure of the treatment and
the intervention used is available (Bockting et al., 2009). Unlike CT for
acutely depressed patients, C-PCT is not primarily directed toward modifying
negative thoughts. Instead, it starts with the identification of negative
thoughts and dysfunctional attitudes, aided by a self report questionnaire with
examples of attitudes and specific techniques. The focus of treatment is then
directed on changing these attitudes using different cognitive techniques. In
addition specific attention will be paid to enhancing the memory and retrieval
of positive experiences and making a person prevention plan.

Burden: Patients participating in this study, and allocated to the experimental
condition receive 8 session of a psychosocial intervention of 1 hour each.
After each session patients will be asked to fill in several short
questionnaires which will take 15 minutes. Patients allocated to the control
condition will fill in the same questionnaires twice witch will take 20
minutes. All participants will be asked to fill in 5 questionnaires each
lasting 60 minutes. All participants will undergo an interview at baseline and
at 15 months witch will take 60 minutes. The total burden for patients in the
control condition is 7.3 hours during the total follow up time of 15 months.
The total burden for patients in the experimental condition is 14.6 hours
during the total follow up time of 15 months. This includes 8 hours of
psychosocial intervention.

Risks: We see no risks for participants.