Acceptance and commitment therapy as an intervention to improve quality of life and activity-engagement in patients with multiple sclerosis.

Multiple Sclerosis (MS) is a chronic disease of the central nervous system and
it is the most common neurological disorder in young adults. MS is an incurable
disease with an unpredictable and often degenerative course. MS can affect both
physical, psychological and emotional functioning and quality of life (QoL).
The most important predictors of QoL in MS are not the physical symptoms and
neurological impairments, but symptoms of fatigue, depression and anxiety.
Fatigue, anxiety and depression are very common in MS with prevalences ranging
between 27% and 54% for depression, between 19% and 35% for anxiety and up to
90% for fatigue. Fatigue is the most disabling symptom of MS patients and is
often a reason for reduced activity-engagement. It is suggested that not only
the severity of these symptoms, but beside others, also coping styles of the MS
patients are important predictors of QoL.
MS patients can profit from psychological interventions to reduce symptoms of
anxiety, depression and fatigue and to improve QoL. There is growing evidence
that cognitive behavioural therapy (CBT) is effective in MS patients. Also,
newer forms of CGT, including Acceptance and Commitment Therapy (ACT) are
promising.
ACT has been proven effective in terms of functionality and quality of life in
several clinical populations, including patients with traumatic brain injury,
chronic pain, anxiety and depression. In chronic pain patients, ACT results in
significant increase of activity engagement. Studies that evaluate the effects
of ACT in MS patients are scarce and to the best of our knowledge there is no
evidence available in the Dutch language area.

The purpose of the current study is therefore to investigate the effectiveness
of an ACT group intervention on both activity engagement and QoL in MS patients
in comparison with a waiting list condition. Furthermore, we hypothesize that
psychological flexibility (including acceptance and cognitive defusion) will
increase, symptoms of depression, anxiety and fatigue will reduce and adaptive
coping styles will improve.

A single case experimental design (SCED) with multiple baselines is chosen with
three waiting list conditions of 3, 6 and 9 weeks, randomized for waiting time.
The intervention period takes 8 weeks with a follow up till three months after
end of intervention.
SCED is a relatively new design for experimental research that is often used to
evaluate the effectiveness of (new) interventions in behavioral medicine,
psychotherapy and rehabilitation medicine.

The therapists will use an 8-session group protocol of two hours, based on the
work of Jansen & Batink (2014) and Luoma & Hayes (2009).
Patients will receive a book with background information and exercises they can
make as homework.

The treatment involves eight weekly meetings of two hours. To complete all the
outcome questionnaires will take about 30 minutes. All outcome measurements
will be performed at inclusion, at the start of the treatment 3, 6 or 9 weeks
later, at the end of the intervention and at follow up at one and three months
after finishing the program.
The main study parameter of activity engagement will be administered weekly;
this will take about 10 minutes. For QoL a daily visual analogue scale must be
scored. This will take less than 5 minutes.
Neuropsychological tests (see E4) will be listed at the start of the study and
will take about 20 minutes.
There are no risks associated with this treatment. In fact, the intervention is
an existing psychological treatment. Patients may experience a physical or
emotional burden because of participation or harm on account of the time
involved.
Our clinical experience is, that MS patients can profit from ACT and that their
QoL will improve. Otherwise, the scientific evidence for these experiences is
not yet available.