The clinical utility of the Breathing Pattern Assessment Tool (BPAT) to identify dysfunctional breathing (DB) in individuals living with postural orthostatic tachycardia syndrome (POTS).

Background: Dysfunctional breathing (DB) resulting in inappropriate breathlessness is common in individuals living with postural orthostatic tachycardia syndrome (POTS). DB in POTS is complex, multifactorial, and not routinely assessed clinically outside of specialist centres. To date DB in POTS has been identified and diagnosed predominately via cardiopulmonary exercise testing (CPEX), hyperventilation provocation testing and/or specialist respiratory physiotherapy assessment. The Breathing Pattern Assessment Tool (BPAT) is a clinically validated diagnostic tool for DB in Asthma. There are, however, no published data regarding the use of the BPAT in POTS. The aim of this study was therefore to assess the potential clinic utility of the BPAT in the diagnosis of DB in individuals with POTS.

Methods: A retrospective observational cohort study of individuals with POTS referred to respiratory physiotherapy for formal assessment of DB. DB was determined by specialist respiratory physiotherapist assessment which included physical assessment of chest wall movement/breathing pattern. The BPAT and Nijgmegen questionnaire were also completed. Receiver operating characteristics (ROC) analysis was used to compare the physiotherapy assessment based diagnosis of DB to the BPAT score.

Results: Seventy-seven individuals with POTS [mean (sd) age 32 (11) years, 71 (92 %) female] were assessed by a specialist respiratory physiotherapist, with 65 (84 %) being diagnosed with DB. Using the established BPAT cut off of four or more, receiver operating characteristics (ROC) analysis indicated a sensitivity of 87 % and specificity of 75 % for diagnosing DB in individuals with POTS with an area under the curve (AUC) of 0.901 (95 % CI 0.803-0.999), demonstrating excellent discriminatory ability.

Conclusion: BPAT has high sensitivity and moderate specificity for identifying DB in individuals living with POTS.