Objective: Paced breathing (slow, deep, diaphragmatic breathing) reduces central sympathetic activity and facilitates the relaxation response. The present study was designed to assess the feasibility of and to obtain initial efficacy estimates of two paced-breathing programs, compared with usual breathing, for the frequency and severity of hot flashes.
Methods: We designed a 9-week, randomized, three-arm, parallel-group, blinded (investigator) phase II clinical trial. Using an audio CD, participants in the active arms practiced paced breathing at 6 breaths/minute for 15 minutes, either once or twice a day, whereas the control arm practiced usual breathing at 14 breaths/minute for 10 minutes/day. Feasibility was assessed through self-report questionnaires; percent reduction and effect size estimates were determined using changes in hot flash frequency and scores within each group.
Results: Of the 92 eligible participants, 68 (74%) completed the study. Most women reported that the intervention was easy to do (79%) and of appropriate duration (71%). They could practice exercises as taught (61%) and could practice on most days (65%). Participants in all arms reported hot flash reductions during the 9 weeks: 52% for paced breathing twice a day, 42% for paced breathing once a day, and 46% for usual breathing.
Conclusions: The paced-breathing intervention is feasible. Although paced breathing twice a day seems to be the most helpful dose, efforts to intensify paced breathing once a day may be more practical for widespread dissemination. The efficacy and overall clinical impact of paced-breathing exercises on hot flash reduction require further evaluation in an adequately powered, placebo-controlled, randomized phase III clinical trial.