Efficacy of positive cognitive behavior group therapy for depression in older adults.

According to the WHO, the global population is aging rapidly with estimations
predicting that the proportion of the world*s population over 60 years of age,
will double from twelve to twenty-two percent between 2015 and 2050.
Additionally, the life expectancy will increase. Globally, about fifteen
percent of the group of adults aged 60 and older suffer from a mental disorder,
with dementia and depression being the most common. In older adults, depression
is often underdiagnosed as well as untreated. This has multiple explanations.
For example: symptoms of depression in older adults are attributed to a
physical problems or seen as a normal part of aging. In addition, older adults
are assumed to disclose less about their mental health issues compared to
younger adults. Interestingly, older adults who are referred for psychological
treatment show better attendance and clinical improvement compared to younger
adults. Additionally, older adults benefit just as much from psychotherapy for
depression as middle aged adults. This suggests that it is worth investing in
the psychological treatment of depression in older adults.

There is ample evidence for the effectiveness of traditional cognitive
behavioral therapy (T-CBT) as treatment for depression. It is also the most
researched and recommended therapy for depression in most guidelines. However,
T-CBT has several limitations. For example, psychotherapy is generally
associated with high drop-out and low homework compliance. In addition, only
about 42% of patients respond to treatment with T-CBT with a remission rate of
36%. Finally, T-CBT is mainly focused on decreasing on depressive symptoms
although research suggests that successful treatment entails more than a
decrease in depressive symptoms (with patients rating an increase in positive
affect as more important).

In recent years there has been increased attention to 4th generation CBT
interventions, such as positive CBT (P-CBT). P-CBT is a novel transdiagnostic
treatment which focuses on positive emotions and integrates T-CBT techniques
with solution-focused therapy and positive psychology. Some of the key features
of positive CBT are assumed to overcome the previously mentioned limitations of
traditional CBT. In adults suffering from depression, positive CBT has shown a
stronger improvement in depressive symptoms compared to traditional CBT. In
addition, research has shown larger effect sizes from negative and positive
affect measures for positive CBT.

Drawing on previous findings, we hypothesize that older adults suffering from
depression profit from positive CBT leading to a decrease in depressive
symptoms and negative affect and an increase in positive affect, optimism,
well-being, subjective happiness and personality functioning.

The aim of the current study is to examine the efficacy of positive CBT for the
treatment of major depressive disorder in older adults. Drawing on previous
findings, we hypothesize that older adults suffering from major depressive
disorder profit from positive CBT leading to a decrease in depressive symptoms
and negative affect and an increase in positive affect, optimism, well-being
and subjective happiness. Additionally, we hypothesize that positive CBT will
lead to an improvement in personality functioning in older adults suffering
from major depressive disorder.

The current study will use a replicated single case design. We choose this
design because this study, to our knowledge, is the first explorative study on
the effectiveness of P-CBT in older adults. The replicated single case design
requires relatively few participants because the participants serve as their
own control in an extensive longitudinal design. Typical for a replicated
single case design are dependent variables which are assessed frequently, thus
making it possible to study the effects of time and intervention. This allows
for a detailed observation of the changes occurring within each subject in
relation to the independent variable and thus the effectiveness of the
treatment.

Participants in the current study will participate in 8 group sessions of
positive cognitive behavioral therapy as described by Bannink (2012) according
to the Positive CBT group treatment protocol (Bannink & Geschwind, 2021). The
treatment will consist of 8 weekly sessions with a duration of 2 hours per
session. The sessions will be led by two health care psychologists who are
familiar with the treatment protocol and who will partake in intervision.

All participants (i.e. patients) partaking in the current study will start with
completing the baseline measurements with the primary outcome measure being
assessed two times per week for five weeks and the secondary outcome
measurements once in total. Next, all participants (i.e. patients) will take
part in the treatment phase. During this phase the primary outcome measure will
be assessed two times a week for 8 weeks. After completion of the group
therapy, participants (i.e. patients) will complete the posttreatment
measurements, which will cover the same measurements as the assessment at
baseline. After three weeks, the primary outcome measurement will be will be
completed two times a week as follow-up for a period of three weeks and the
secondary outcome measurement will be completed once again in total. Informants
will complete the two informant questionnaires once at baseline, posttreatment
and follow-up.

For the present study, patients who are diagnosed with depression will
participate in eight weeks of cognitive behavioral group therapy. The
participation in such therapy is common practice in the treatment of
depression, making this no extra burden. In cognitive behavioral therapy, as
commonly used in daily practice, it is not uncommon to incorporate positive and
solution-based elements. The main difference for the current study is the
protocolized use of positive behavioral therapy and the more clear focus on
these positive and solution-based interventions while preserving the key
elements of (traditional) cognitive behavioral therapy, such as thought
records, cognitive restructuring, etc. The more light-hearted, future-oriented,
solution-based and positive approach could make this treatment even less of a
burden than traditional cognitive behavioral therapy.

Patients will start the actual treatment after five weeks of baseline
measurements. This corresponds with a normal waiting time to start treatment
after an intake procedure and should impose no extra burden. Patients who are
not able to wait five weeks for the start of treatment (e.g. due to a strong
crisogenic presentation) will be excluded from the study and will receive other
treatment fitting to their symptoms. The treatment interventions used in this
study have proven to be beneficial in the treatment of depression in adults.
Therefore, no risks are expected for the older adults participating in this
study.

During the current study, patients and informant are asked to complete several
questionnaires (see Appendix 1). The primary outcome measurement will be
assessed during baseline (duration of 5 weeks), treatment (duration of 8
weeks), after treatment (duration of 1 week), and follow-up after a three week
interval (duration of 3 weeks). The primary outcome measurement will be
assessed two times a week with each assessment taking up a maximum of 5
minutes. This cumulates to 170 minutes in total for the entire study for the
primary outcome measurement. In addition, participants will be asked to
complete the secondary outcome measurement four times in total (baseline,
treatment, post-treatment, and follow-up). The completion of the secondary
outcome measurement is estimated to take up a maximum of 45 minutes each time.
This cumulates to 180 minutes in total for the entire study for the secondary
outcome measurement. Lastly, an informant will be asked to complete two
questionnaires during baseline, after treatment and at follow-up. Completing
these questionnaires takes up a maximum of 15 minutes each time, cumulating to
an investment of 45 minutes in total for the informant.

In order to support the patients, a weekly monitoring contact with a therapist
is provided in the phase before and after te group treatment. No interventions
are carried out during these contacts, but the patient's condition is monitored
and they are asked whether the completion of the questionnaires is going well.

Participants in the current study will receive no financial compensation for
participation.