This study aimed to evaluate the effects of BBT training on asthma control, quality of life, and pulmonary function among asthma patients.The findings suggest that BBT may be a potentially effective complementary approach. However, given the small sample size and short follow-up duration, larger studies with longer-term follow-up are necessary to confirm and generalize these results.

According to certain perspectives, hyperventilation plays a significant role in the manifestation of asthma symptoms. The Buteyko Breathing Technique (BBT), which targets dysfunctional breathing patterns, has been reported to reduce symptoms of hyperventilation and associated anxiety in asthmatic individuals.

This study aimed to evaluate the effects of BBT training on asthma control, quality of life, and pulmonary function among asthma patients.

Between June 2018 and June 2019, this randomized controlled trial was conducted at the asthma outpatient clinic of a university hospital. Approximately 450 asthma patients presented during the study period; 36 eligible participants were assessed, 12 were excluded, and the remaining 24 individuals were randomized (block randomization, block size = 4) into an intervention group (n=12) and a control group (n=12). The intervention group received BBT training and daily practice sessions, while the control group received standard breathing education-based on the "Life with Asthma" booklet-including abdominal and diaphragmatic breathing techniques. All participants were evaluated at baseline and at week 6 using the Asthma Control Questionnaire (ACQ), Asthma Quality of Life Questionnaire (AQLQ), and pulmonary function tests (FEV₁, FEV₁/FVC, control pause (CP)). Data were analyzed using SPSS 25.0; independent t-tests, Mann-Whitney U tests, and repeated-measures ANOVA were applied.

Inclusion criteria included patients who:

• were followed in the asthma outpatient clinic of the university hospital,
• had stable asthma (no exacerbation in the last 6 weeks),
• had no communication problems,
• had no history of smoking,
• were using inhaled corticosteroids regularly (without dose changes in the past 4 weeks),
• voluntarily agreed to participate in the study.

Exclusion criteria were as follows:

• presence of another chronic pulmonary disease (e.g., COPD, bronchiectasis),
• psychiatric illness history or use of psychiatric medications,
• cognitive impairment or inability to follow instructions,
• pregnancy or breastfeeding,
• participation in another clinical trial simultaneously.

The individual participant data will not be shared due to ethical and privacy concerns.