Refractory chronic cough Unexplained chronic cough
Conditions
Interventions
None listed
Sponsors
Tokai University
Eligibility
Sex/Gender
All
Inclusion criteria
Inclusion criteria: Eligibility criteria for our evidence-based research question included phase II-III randomized controlled trials (RCTs) that met the following criteria: (1) participants with refractory or unexplained chronic cough of any age, (2) treatment with P2X3 receptor antagonists, (3) comparison with a placebo or other P2X3 receptor antagonists, and (4) reporting of safety and efficacy outcomes.
Exclusion criteria
Exclusion criteria: We excluded studies that compared P2X3 receptor antagonists with any other active treatment, as well as animal trials, abstracts, and any study designs other than RCTs.
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| The primary outcomes were the 24-hour cough frequency and the incidence of taste disturbances. The efficacy outcomes comprised the 24-h cough frequency (coughs per hour), evaluated as a percentage change from baseline, where a reduction indicated improvement. The minimum important difference (MID) was considered a 20% reduction. Taste disturbances with MIDs of 15 in absolute risk difference per 100 patients. | — |
Secondary
| Measure | Time frame |
|---|---|
| Secondary outcomes included cough severity using the Visual Analogue Scale (VAS), Leicester Cough Questionnaire (LCQ) total score, treatment-related adverse events (AEs), discontinuation due to AEs, and serious AEs. The VAS, ranging from 0 mm (symptom-free) to 100 mm (severe), assessed subjective characteristics. A reduction in VAS score indicated improvement, with a MID of a 30 mm reduction. The LCQ total score, ranging from 3 to 21, evaluated quality of life, with a lower score indicating greater impairment due to cough. An increase in LCQ score signified improvement, with a MID of a 1.3-point increase. Safety outcomes included serious AEs, and discontinuation due to AEs, treatment-related AEs, with MIDs of 5, 10, and 15 in absolute risk difference per 100 patients, respectively. To gather missing or unclear data from primary studies, we (1) contacted corresponding authors and (2) referred to supplementary files or online server data. We assumed crossover trials as parallel trials following Cochrane's recommendations. | — |
Countries
Japan
Contacts
Public ContactShota Yamamoto
Tokai University Graduate School of Medicine
Outcome results
None listed