Effect of biofeedback on heart rate variability on the levels of state-trait anxiety of health care professionals nursing: randomized clinical trial

INTRODUCTION: In the global work scenario, nursing professionals represent approximately 59% of the health workforce, characterizing a profession that articulates various care, management, educational, preventive, political and research processes. The interaction of anxiety with increased workload, physical exhaustion and some characteristics of work environments can have dramatic effects on workers' physical and mental well-being. Heart rate variability biofeedback may be considered an alternative intervention in the management of a health risk or condition. OBJECTIVE: To evaluate the effect of the intervention with biofeedback of heart rate variability (HRV) on the levels of Trait-State anxiety of nursing professionals at a university hospital, when compared with a computerized activity without self-monitoring. METHODS: parallel randomized clinical trial with 115 nursing professionals, comparing two groups during 9 meetings, having stress and state-trait anxiety levels as study factors, conducted from June 2020 to August 2020. 2021. Participants in the intervention group used the EmWave Pro Plus® software to measure heart rate variability biofeedback and the main outcome instrument was self- administered in the pre- and post-intervention phases. Data were grouped in spreadsheets and analyzed using the STATA 14.0 program, using descriptive and inferential statistics. RESULTS: There is a positive correlation between state trait anxiety scores, stress scores and stress dimensions (rho = 0.811, p < 0.001). The differences in state anxiety deltas (0.99, 95%CI=-2.01-3.99, p=0.514) and trait (0.7, 95%CI=-1.85-3.26, p=0.586) were not statistically significant in the biofeedback intervention group compared with the control. Likewise, the differences in state anxiety deltas (0.70, 95%CI=-1.85-3.26, p=0.586) and trait (0.71, 95%CI=-1.60-3.02, p =0.546) adjusted for the respective baseline levels of anxiety, were also not significantly different between the groups. CONCLUSION: The results suggest that heart rate variability biofeedback intervention has no effect on anxiety levels in nursing professionals. The findings suggest that the interaction between anxiety and occupational stress can be considered a point of reference for further research; also the need for new ones that allow comparing biofeedback with other complementary therapies.