Non-pharmacological interventions for adults with intellectual disabilities and depression

Background: Although high rates of depression symptoms are reported in adults with intellectual disabilities (IDs), there is a lack of knowledge about non-pharmacological treatment options for depression in this population. The first research question of this paper is: Which non-pharmacological interventions have been studied in adults with ID and depression? The second research question is: What were the results of these non-pharmacological interventions?. Method: Systematic review of the literature with an electronic search in six databases has been completed with hand searches. Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines have been followed. Selected studies met predefined inclusion criteria. Results: Literature search resulted in 4267 papers of which 15 met the inclusion criteria. Five different types of non-pharmacological interventions have been studied: cognitive behavioural therapy, behavioural therapy, exercise intervention, social problem-solving skills programme and bright light therapy. Conclusion: There are only a few studies of good quality evaluating non-pharmacological interventions for adults with ID and depression. Some of these studies, especially studies on cognitive behavioural therapy, show good results in decreasing depressive symptoms. High-quality randomised controlled trials evaluating non-pharmacological