Does mindfulness heighten emotional resilience against depression?
A study of gene-person-environment interactions.

Rationale: The experience of positive emotions reduces daily life stress-sensitivity, an endophenotype for depression, but also attenuates the expression of genetic risk for depression. This research proposal, therefore, will focus on the changeability (plasticity) of the ability to experience positive emotions in response to daily life events (natural rewards), as a first step towards novel (preventive) interventions in depression



Objective:

1. Can the ability to experience reward in daily life be experimentally modified?;

2. How does experimental modification of reward impact on depressive symptomatology and can individual variation be traced to genetic variation.




Study design: An intervention study is used in which subjects are randomized to treatment as usual (TAU) or TAU + mindfulness-based cognitive therapy. Experience Sampling Method (ESM) is a structured diary, momentary assessment technique to study subjects in their daily life. Before and after the intervention subjects undergo a six-day period of ESM assessment. Subjects will be globally informed, but remain blind as to how ESM measures relate to testing the hypothesis.



Study population: A sample of 120 depression-remitted adult subjects with residual symptomatology (Ham-17>7) recruited from the community mental health centre in Maastricht (CMHC).




Intervention: The experimental group receives 8 weeks of mindfulness training by an experienced trainer in addition to their normal treatment, if any. Sessions are weekly (2,5 hours a session) and subjects receive daily homework exercises. The control group continues their normal treatment, if any.



Main study parameters/endpoints: The increase in reward experience in daily life, whereby reward experience is conceptualised as the effect of small daily life positive events on positive mood state. Since ESM measurements are performed 10 times a day for 6 days, there will be a maximum of 60 measurements within each subject concerning effects of positive events on positive mood state in the flow of daily life.

1. Mindfulness training can be used to modify the ability to experience positive emotions from everyday life situations assessed with ESM (reward experience);

2. Experimentally induced increases in reward experience in daily life will reduce depressive symptoms in patients with residual symptomatology and will lead to reduced risk for future relapse;

3. Polymorphisms of genes related to the brain reward system are associated with reward experience in daily life and its modifiability.

1. Premeasure: 6 days ESM;

2. postmeasure: after 8 weeks of mindfulness training/time control: 6 days ESM;

3. follow-ups are planned, but were not yet submitted to ethical committee:

4. Follow-up at 6 months;

5. Follow-up at 12 months.

Mindfulness-based cognitive therapy vs. non-active control group. The experimental group receives 8 weeks of mindfulness training by an experienced trainer in addition to their normal treatment, if any. Sessions are weekly (2,5 hours a session) and subjects receive daily homework exercises. The control group continues their normal treatment, if any.