Mind-Body Medicine and Immune System Outcomes: A Systematic Review

Objectives: The objectives of this systematic review were to: 1) characterize mind-body medicine studies that assessed immune outcomes, 2) evaluate the quality of mind-body medicine studies measuring immune system effects, and 3) systematically evaluate the evidence for mind-body interventions effect on immune system outcomes. Data Sources: Data sources included MEDLINE, PsycINFO, CINAHL, Alt HealthWatch, Allied and Complementary Medicine Database, Cochrane Library, Database of Abstracts of Reviews of Effects, Health Technology Assessment Database. Review Methods: Selection criteria included publications in any language, all study designs and participant types, mindbody interventions, and any immune outcome. Quantitative and qualitative data were extracted and quality assessments were made independently by 2 reviewers. Meta-analysis was not possible due to study heterogeneity. The Natural Standard evidence-based validated grading rationale was employed to evaluate the evidence. Results: 111 studies with 4,777 subjects were reviewed, 81 of which were RCT’s. The three largest intervention type categories were Relaxation Training (n=25), Cognitive Based Stress Management (n=22), and Hypnosis (n=21). Half the studies were conducted with healthy subjects (n=51). HIV (n=18), cancer (n=13) and allergies (n=7) were the most prominent conditions examined in the studies comprising of non-healthy subjects. Natural killer cell and CD4 T lymphocyte measures were the most commonly studied outcomes. Conclusions: Most categories had limited or inconclusive evidence. Relaxation training had the strongest scientific evidence for affecting immune outcomes. Immunoglobulin A had the strongest scientific evidence for positive effects from mind-body medicine. Issues for mind-body medicine studies with immune outcomes are discussed and recommendations are made to help improve future clinical trials.