Understanding the dynamics of inflammatory mediators in response to mind-body movement therapies (MBMTs): A systematic review and meta-analysis of studies in healthy subjects.

Background: Modulation of inflammation has been proposed as a potentially important aspect of mind-body movement therapies (MBMTs). Research from the sports medicine has delineated the inflammatory cascade after conventional exercise; however, relatively less is known regarding modulation of inflammation after MBMTs. Objective: To synthesize the available literature investigating the short- and long-term impact of MBMT interventions on systemic inflammatory mediators in healthy individuals. Methods: We conducted a systematic review and meta-analysis of inflammatory mediators according to Preferred Reporting Items for Systematic Review and Meta-Analyses Guidelines. We sought RCTs in healthy individuals comparing MBMTs with passive or active controls that measured systemic inflammatory markers. We used the Cochrane risk-of-bias tool for randomized trials. Hedges's g and 95% CIs were computed across studies. Results: Of 3122 studies identified, 23 were eligible for synthesis. Most common MBMTs studied were yoga(n = 11), qigong(n = 4), tai chi(n = 3), MBSR(n = 3), and dance therapy(n = 2). Frequency of practice (most commonly 3 times/week), intervention duration (3 short-term, single session and 20 long-term with repeated sessions for > 1 week), and session length (most commonly 30-60 min) showed high heterogeneity between studies. Pro- and anti-inflammatory proteins were most commonly measured (n = 20 studies), followed by immune cells (n = 5), lipid mediators (n = 4), and humoral and complement factors (n = 2). Most showed no change or decrease in inflammatory mediators, with fewer showing increased levels. Meta-analyses suggested a significant decrease in systemic levels of CRP (Hedges's g = -0.351; CI = -0.580, -0.123) and TNF-α (Hedges's g = -0.366; CI = -0.669, -0.064), and a trend toward decreased IL-6 after long-term MBMTs (Hedges's g = -0.394; CI = -0.819, 0.030). Conclusion: While findings suggest inflammatory proteins, including CRP, TNF-α, and IL-6 decrease with long-term MBMTs similar to conventional exercise, the overall trajectory of change in inflammatory mediators after MBMT may be more nuanced. Future carefully-controlled studies including precise intervention parameters evaluating pre-post changes will be required to understand both short- and long-term effects of MBMTs, as well as gauge how these changes relate to symptom relief when employed in patients with chronic conditions. PROSPERO ID CRD42022315399.