Positive expiratory pressure (PEP) flute therapy led to a small yet statistically significant decrease in the severity of respiratory symptoms in adults with COVID-19 recovering at home, according to results of an open-label, randomized controlled trial published in BMJ.
Between October 2020 and February 2021, investigators recruited community-dwelling adults with symptomatic SARS-CoV-2 infection, confirmed via reverse transcription polymerase chain reaction testing, who were able to perform self-care. Patients were randomly assigned in a 1:1 fashion to receive either standard care or standard care plus PEP flute self-care, administered 3 times daily for 30 days. Standard care included self-quarantine, adequate fluid intake, and over-the-counter medications to relieve symptoms. All patients completed a daily chronic obstructive pulmonary disease assessment test (CAT). The primary outcome was a change in symptom severity from baseline to day 30 based on self-reported CAT scores, with adjustments for baseline values and stratification by age and sex. Secondary outcomes were self-reported urgent care center visits for COVID-19, the number of COVID-19-related symptoms, and change in self-rated health.
Among a total of 378 patients included in the study, 190 received standard care plus PEP flute self-care and 188 received standard care alone. Overall, most patients were women (72.5%) and younger than 60 years (85.7%; range, 19-80 years), and most (95.8%) self-rated their health as “good” or “excellent” prior to developing COVID-19. The median duration of COVID-19-related symptoms at enrollment was 4 days (IQR, 3-7 days), and cough was the predominant respiratory symptom.
Patients in the PEP flute self-care group used the PEP flute for a median of 21 days (IQR, 13-25 days) for a median of 2.5 sessions daily (IQR, 1.5-2.9). The investigators found that the mean number of daily PEP sessions decreased as mean CAT scores decreased during the 30-day study period. Among patients in the PEP flute self-care group, investigators noted a significant decrease in CAT scores from baseline to day 30 (-1.2 points; 95% CI, -2.1 to -0.2; P =.017). There also was a small yet significant increase in self-rated health scores from baseline to day 30 among patients in the PEP flute group (0.2 points; 95% CI, 0.01-0.4; P =.041). In a sensitivity analysis of individual CAT items, there was a significant difference between groups for chest tightness (-0.24 points; 95% CI, -0.40 to -0.09; P =.002), dyspnea (-0.28 points; 95% CI, -0.46 to -0.09; P =.004), activities of daily living (-0.40 points; 95% CI, -0.60 to -0.21); P <.001), and vigor (-0.42 points; 95% CI, -0.62 to -0.22; P <.001).
Among patients in both groups, no significant differences were found in regard to mean changes in CAT respiratory sub-scores from baseline to day 30, nor in the mean number of COVID-19-related symptoms or urgent care visits. Of note, 20 participants reported adverse events related to PEP use, though none were severe.
This study was limited by contamination bias as 4 patients obtained their PEP flute without a prescription. Other limitations include the lack of objective outcome measures and the use of CAT scores to evaluate COVID-19 symptom severity.
According to the investigators, “as a global response to pandemics, more research is needed into home based interventions that are safe and of low cost, and that can be easily distributed and scaled up.”
Mollerup A, Henrikson M, Larsen SC, Bennetzen AS, Simonsen MK, Kofod LM, et al. Effect of PEP flute self-care versus usual care in early covid-19: Non-drug, open label, randomised controlled trial in a Danish community setting. BMJ. Published online November 24, 2021. doi:10.1136/bmj-2021-066952