ENGAGEMENT IN SOCIALLY REWARDING ACTIVITIES AS A PREDICTOR OF OUTCOME IN BEHAVIORAL ACTIVATION THERAPY FOR LATE LIFE DEPRESSION

Introduction Late life depression has detrimental effects on older adults’ functioning and well-being. Depressed older adults often experience loneliness and social isolation, which are risk factors for incident depression, increased depression severity, and medical illness. Neurobiological studies suggest that depressed individuals of all ages exhibit impairments in the reward systems and recent studies suggest that socially rewarding experiences may be especially important for depressed older adults. Results of a pilot study conducted by our group has shown that “Engage”, a neurobiologically informed, streamlined brief behavioral activation for depression, led to significant reduction in depressive symptoms. “Engage” targets impairments in positive valence system function through “reward exposure” (i.e. engagement in rewarding and meaningful activities). However, it is unknown whether engagement in certain types of rewarding activities is more beneficial than others. We predicted that given the centrality of social isolation in late life depression, social (versus non-social) rewarding activities would predict greater improvement in depression severity. Methods Forty-eight older adults with unipolar depression without cognitive impairment received 9 sessions of “Engage” psychotherapy. Depression severity was assessed using the Montgomery–Asberg Depression Rating Scale (MADRS) and behavioral activation was measured using the Behavioral Activation for Depression Scale (BADS) at baseline, weeks 6 and 9. We also assessed depression severity on a weekly basis using the Patient Health Questionnaire (PHQ-9). Patients’ weekly behavioral plans were categorized into three groups: a) solitary activities; b) social-group activities (attending a social gathering or going to a social setting such as church or a senior center); c) social-individual activities (engaging in an interpersonal interaction with a specific friend and/or family member). Results Logistic regression analyses showed that higher percentage of social-individual activities (compared to solitary and social-group activities) predicted subsequent improvement in depressive symptoms and increase in behavioral activation, when controlling for baseline scores on MADRS and BADS respectively. Preliminary analysis suggests that patients who selected social individual activities, in addition to solitary and social group activities, had a steeper reduction of depression by the third session compared to patients lacking social individual activities in their reward exposure plans. This observation suggests that engagement in social individual activities is associated with early response of depression to Engage. Conclusions Our preliminary results suggest that exposure to socially rewarding experiences could contribute to the efficacy of psychotherapy for late-life depression. Additionally, these findings highlight the importance of studying the effects of engagement in specific types of rewarding activities in behavioral activation treatment for late-life depression. This research was funded by P50 MH113838 R01 MH102252 T32 MH019132