Psychological interventions for depression and anxiety: a systematic review and meta-analysis of Iranian chronic pain trials.

Background: Chronic pain is commonly associated with anxiety and depression, making it more challenging to be managed. Psychological interventions are suggested for such complicated issues which are well evident in the United States and Europe. However, generalizing the evidence to Iranian population - as a Middle Eastern society - might be questionable. We aimed to synthesize our evidence on the effectiveness of these interventions among Iranian populations. Methods: This was a systematic review and meta-analysis. Persian and English literature were searched through Iran-doc, Elm-net, and PubMed until March 2019 using the following terms (or its Persian synonyms): chronic pain; persistent pain; chronic fatigue; fibromyalgia; neuropath*; LBP; irritable bowel; CFS; psycho*; cogniti*; acceptance; meaning; mindfulness; relaxation; biopsychosocial; rehabilitation; educat*. Eligible trials were randomized trials that evaluated the effectiveness of psychological interventions on Iranian adults with chronic pain. No setting restriction was considered. Risk of bias for each trial was assessed, and the random-effect model was used to pool summary effect across trials. Results: In all 30 eligible RCTs, the risk of bias for randomization was low except for one study. The pooled standardized mean difference (SMD) for depression and anxiety were 1.33 (95%CI: -1.42 to -0.68) and 1.25 (95% CI: -1.55 to -0.96), respectively. Conclusion: This study suggests that psychological interventions are highly effective in reducing depression and anxiety in Iranian patients with chronic pain, compared to what observed in the U.S. and European studies. However, there are still some methodological issues to be addressed. Future research should focus on high-quality trials with considerations on the methodological issues reported in the present study.