Question: “In adults with anxiety and depression, how effective is laughter therapy, compared to any other intervention, in improving patient outcomes?”

Answer:

All four small, methodologically weak RCTs reported some data to suggest that laughter therapy may have some positive effects on measures of emotional well-being, symptoms of depression and anxiety, and sleep disturbance in elderly people with dementia. However, findings were inconsistent across studies and no reliable conclusions on the effectiveness of laughter therapy can be drawn. None of the studies included in this evidence summary were conducted in a general adult population
with a diagnosis of depression and anxiety; three included only elderly participants and only one specified a diagnosis of depression as an inclusion criterion. All of the identified studies are likely to have limited generalisability to the management of anxiety and depression in a general adult population in the UK.

Further research is needed to assess the effectiveness of laughter therapy, specifically in people with diagnoses of depression and anxiety.