Five-week yin yoga-based interventions decreased plasma adrenomedullin and increased psychological health in stressed adults: A randomized controlled trial

BACKGROUND: Non-communicable diseases (NCDs, e.g. cardiovascular disease) are responsible for high rates of morbidity and the majority of premature deaths worldwide. It is necessary to develop preventative interventions that can reduce the associated risk factors of NCDs. Researchers have found that the biomarker adrenomedullin (ADM) becomes elevated years before the onset of NCDs and might play an important role in their development. ADM has also been linked to psychological problems such as stress, anxiety, and depression, which are known risk factors of NCDs. In this randomized controlled trial, we examined whether participating in a five-week yoga intervention reduces ADM and increases psychological health in middle-aged adults who self-report as moderately to highly stressed, but who otherwise exhibit no physical complaints. METHODS: One hundred and five adults (78% women; mean age = 53.5, SD = 6.7) were randomly assigned to (1) a five-week Yin yoga intervention, (2) a five-week intervention combining Yin yoga with psychoeducation and mindfulness practice (called the YOMI program), or (3) a control group who did not practice yoga or mindfulness for five weeks. RESULTS: Compared to the control group, we observed significantly greater pre-post reductions in plasma ADM levels (p < .001), anxiety (p ≤ .002), and sleep problems (p ≤ .003) in both intervention groups. Furthermore, the YOMI group exclusively showed significantly greater pre-post reductions in stress (p = .012) and depression (p = .021) compared to the control group. Significant correlations (p < .05) were found between pre-post reductions in ADM and anxiety symptoms (p = .02) and depression (p = .04) in the entire sample. CONCLUSION: The five-week Yin yoga-based interventions appeared to reduce both the physiological and psychological risk factors known to be associated with NCDs. The study suggests that incorporating Yin yoga could be an easy and low-cost method of limiting the negative health effects associated with high stress. TRIAL REGISTRATION: ClinicalTrials.gov NCT03428542.