Impact of Intensive Social Interaction on Post-Stroke Depression in Individuals With Aphasia

Background. Individuals with post-stroke aphasia often experience a profound loss of abilities to engage in social interaction, one major reason for increased risk of depression after a cerebrovascular accident. Impaired communication skills in aphasia can prevent classical forms of psychotherapy, thus emphasizing the need for new rehabilitation strategies alongside antidepressant medication.

Aims. The present parallel-group, single-center, blinded-assessment controlled trial seeks to explore the feasibility - in terms of high completion rates (primary outcome) - and potential efficacy (co-primary and secondary outcomes, as defined below) of intensive communicative-pragmatic social interaction for treatment of post-stroke depression in subacute aphasia. In this early time window after a cerebrovascular accident, prevalence of post-stroke depression is generally high.

Methods. Treatment is based on a linguistically validated protocol that encourages individuals with aphasia to use neural resources of verbal communication embedded in intensive social interaction. In a routine-healthcare outpatient setting, 60 individuals with post-stroke depression and subacute aphasia will be assigned to one of two groups in a pseudorandomized fashion: (i) intensive communicative-pragmatic social interaction combined with standard care, or (ii) standard care alone.

Endpoints and Outcomes. Apart from evidence of treatment feasibility, endpoint will be change on self-report and clinician-rated measures of depression severity (co-primary outcomes: Beck's Depression Inventory, BDI; and Hamilton Rating Scale for Depression, HAM-D) after a 1-month treatment period (5 hours of weekly training). Secondary outcomes include measures evaluating self-efficacy, quality of life, and language performance (secondary outcomes: Self-Efficacy Questionnaire; and Aachen Aphasia Test, AAT).

Hypotheses. Aside from evidence of treatment feasibility, the primary hypothesis predicts significant between-group differences on BDI and HAM-D scores, indicating greater reduction in depression severity with intensive communicative-pragmatic social interaction over and above standard care alone. Secondary analyses will focus on the Self-Efficacy Questionnaire as an external criterion to explore the psychometric adequacy of the self-report co-primary outcome, the BDI, and consider progress in language performance from onset to end of treatment on the AAT to account for the potential relationship between change in cognitive-affective distress and verbal expression skills.

Clinical Relevance. The current proof-of-concept trial will investigate the feasibility and potential efficacy of intensive communicative-pragmatic social interaction as a means to promote recovery from post-stroke depression in subacute aphasia. The results obtained will determine the design of a subsequent phase-III randomized controlled trial.

Inclusion criteria

• Left-hemisphere cortical or subcortical stroke;
• Native speaker of German;
• Right-handedness according to the Edinburgh Handedness Inventory (Oldfield, 1971);
• Diagnosis of post-stroke depression, as defined in the International Statistical Classification of Diseases and Related Health Problems (ICD-11);
• Diagnosis of aphasia, as confirmed by standardized tests (e.g., Huber et al., 1984); and
• Late subacute or consolidation phase (i.e., 0.5-6 months following stroke) where risk of post-stroke depression is particularly high (Shi et al., 2014).

Exclusion criteria

• Other neurological conditions;
• Pre-morbid history of depression;
• Other psychopathological conditions;
• Severely impaired vision or hearing that may prevent participants from engaging in intensive communicative-pragmatic social interaction during therapy or testing, thus adopting routine-healthcare standards from a large-scale phase-III randomized controlled trial (Breitenstein et al., 2017);
• Serious non-verbal cognitive deficits; and
• No informed consent.