Study: NCT03735576

Intervention type: BEHAVIORAL
Group type: EXPERIMENTAL
Intervention: Psychotherapy
Description: 15-session individually-delivered CBT specific for LLD in comparison with a supportive unspecific intervention (SUI) of the same quantity

Intervention type: BEHAVIORAL
Group type: ACTIVE_COMPARATOR
Intervention: Psychotherapy
Description: 15-session individually-delivered CBT specific for LLD in comparison with a supportive unspecific intervention (SUI) of the same quantity

Intervention type: DIAGNOSTIC_TEST
Group type: EXPERIMENTAL
Intervention: Questionnaires
Description: There will be a total of four assessments (see primary \& secondary endpoints). The first visit of the study will be a screening and baseline (T0) visit. After the baseline assessment, the subjects will be randomized to either of the two treatment arms. Within one week, the first of the successive bi-weekly 50-minute individual face-to-face treatment sessions will be performed by a study therapist. After 7 therapy sessions, the primary and secondary outcomes will be obtained in week 5 (T1) by the blinded rater. This will be followed by the treatment sessions 8 to 15 which will be carried out by the therapist. End-of-treatment primary and secondary outcomes will be obtained in week 10 (T2). The final follow-up assessment (T3) will be performed 6 months after randomization by the blinded rater.

Intervention type: DIAGNOSTIC_TEST
Group type: ACTIVE_COMPARATOR
Intervention: Questionnaires
Description: There will be a total of four assessments (see primary \& secondary endpoints). The first visit of the study will be a screening and baseline (T0) visit. After the baseline assessment, the subjects will be randomized to either of the two treatment arms. Within one week, the first of the successive bi-weekly 50-minute individual face-to-face treatment sessions will be performed by a study therapist. After 7 therapy sessions, the primary and secondary outcomes will be obtained in week 5 (T1) by the blinded rater. This will be followed by the treatment sessions 8 to 15 which will be carried out by the therapist. End-of-treatment primary and secondary outcomes will be obtained in week 10 (T2). The final follow-up assessment (T3) will be performed 6 months after randomization by the blinded rater.

Intervention type: OTHER
Group type: EXPERIMENTAL
Intervention: Magnetic Resonance Imaging
Description: Underlying mechanisms are examined using neuroimaging. MRI data are acquired at four scanning sites and will be performed at baseline, end-of-treatment and follow-up to obtain a high-resolution structural T1-weighted image, a T2-weighted FLAIR image, a resting state fMRI, and diffusion tensor imaging (DTI) of the subjects' brain.

Intervention type: OTHER
Group type: ACTIVE_COMPARATOR
Intervention: Magnetic Resonance Imaging
Description: Underlying mechanisms are examined using neuroimaging. MRI data are acquired at four scanning sites and will be performed at baseline, end-of-treatment and follow-up to obtain a high-resolution structural T1-weighted image, a T2-weighted FLAIR image, a resting state fMRI, and diffusion tensor imaging (DTI) of the subjects' brain.

Intervention type: OTHER
Group type: EXPERIMENTAL
Intervention: Blood analysis
Description: Blood sampling will be acquired in order to investigate the underlying mechanisms in LLD and the specific effects of psychotherapy. Blood samples are acquired at five sites at baseline (T0), T1, T2 and T3 for genetic and epigenetic analyses, measurement of Amyloid-β, Neurofilament light chain (NFL), Peripheral Blood Mononuclear Cells (PBMCs), Metabolomics, Proteomics and miRNA analyses.

Intervention type: OTHER
Group type: ACTIVE_COMPARATOR
Intervention: Blood analysis
Description: Blood sampling will be acquired in order to investigate the underlying mechanisms in LLD and the specific effects of psychotherapy. Blood samples are acquired at five sites at baseline (T0), T1, T2 and T3 for genetic and epigenetic analyses, measurement of Amyloid-β, Neurofilament light chain (NFL), Peripheral Blood Mononuclear Cells (PBMCs), Metabolomics, Proteomics and miRNA analyses.