Neural processing of respiratory sensations in patients with dysfunctional breathing

<bold>Introduction:</bold> Dysfunctional breathing (DB) is typically characterized by dyspnea without a known underlying organic cause. <bold>Aims:</bold> We examined whether increased neural processing could partly explain the experience of such respiratory sensations. <bold>Methods:</bold> 10 DB patients (4 female, <italic>M</italic>_age=44 yrs, <italic>M</italic>_FEV1%pred=102.3, Nijmegen questionnaire total score>23) and 10 healthy controls (4 female, <italic>M</italic>_age=44 yrs, M_FEV1%pred=105.6) received brief inspiratory occlusions every 2nd-6th breath during unloaded breathing, to evoke respiratory-related evoked potentials (RREP) in the electroencephalogram. <bold>Results:</bold> The average mean amplitude of the RREP component N1 was larger in the DB (<italic>M</italic>=-5.03 µV, <italic>SD</italic>=3.65) compared to the control group (<italic>M</italic>=-3.22 µV, <italic>SD</italic>=1.20) with a medium effect size (Cohen’s <italic>d</italic>=-.67), but this difference did not reach statistical significance (<italic>t</italic>(18)=-1.49, <italic>p</italic>=.15). Similarly, the mean amplitude of RREP component P3 tended to be larger in the DB (<italic>M</italic>=5.20 µV, <italic>SD</italic>=4.20) compared to the control group (<italic>M</italic>=4.38 µV, <italic>SD</italic>=2.49, <italic>d</italic>=.24), but this difference was also not statistically significant (<italic>t</italic>(18)=.53, <italic>p</italic>=.60). <bold>Conclusions:</bold> While the results in this preliminary sample suggest trends for increased neural processing of respiratory sensations in DB patients, a larger sample is being collected to confirm whether these trends will reach statistical significance. <fig><object-id>erj;64/suppl_68/OA1883/F1</object-id><object-id>F1</object-id><object-id>F1</object-id><graphic></graphic></fig>