Comment: The quality of evidence is downgraded by study limitations (lack of blinding in 2 studies and no sham treatment in 2 studies).
A Cochrane review [Abstract] 1 included 3 studies with a total of 429 subjects. In bronchial thermoplasty controlled radiofrequency-generated heat is delivered via a catheter inserted into the bronchial tree of the lungs through a flexible bronchoscope and thus reducing airway smooth muscle. Two studies compared bronchial thermoplasty vs medical management and one compared bronchial thermoplasty vs a sham intervention. There was no difference in symptom control or pulmonary function parameters but proportion of participants visiting the emergency department for respiratory symptoms were reduced (table T1). Quality of life was improved with bronchial thermoplasty, although that was not clinically significant. Two trials reported on exacerbations: One showed no significant differences in number of severe exacerbations per week. Another study showed a lower rate of severe exacerbations per participant per year in thermoplasty group compared with controls (0.48 ± 0.067 vs 0.70 ± 0.122 exacerbations per patient-year, respectively) and a significantly lower proportion of participants experiencing severe exacerbations (26% vs 40% of participants). Risk of respiratory adverse events (mostly mild or moderate) and hospitalisation for respiratory adverse events during the treatment period of thermoplasty were higher (table T1).
| Outcomes: Follow-up: mean 12 months | Relative effect(95% CI) | Assumed risk - Control | Corresponding risk - Intervention (95% CI) | No. of participants(studies) Quality of the evidence |
|---|---|---|---|---|
| Quality of life (AQLQ)AQLQ scores. Scale from 1 to 7 (a change of 0.5 points is considered to have clinical relevance) | - | Mean AQLQ ranged from5.1 to 5.7 | Mean AQLQ was0.28 higher(0.07 to 0.50 higher) | 429(3) Moderate |
| Asthma control (ACQ)ACQ scores. Scale from 0 to 36 | - | Mean change in ACQ ranged from-0.55 to -0.01 | Mean change in ACQ was0.15 lower(0.40 lower to 0.10 higher) | 429(3) Moderate |
| Participants admitted to hospital because of respiratory adverse events (treatment period) | RR 3.5 (1.26 to 9.68) | 2 per 100 | 8 per 100(3 to 23) | 429(3) High |
| Participants admitted to hospital because of respiratory adverse events (post-treatment period) | RR 1.12 (0.44 to 2.85) | 4 per 100 | 5 per 100(2 to 12) | 429(3) Moderate |
| Use of rescue medication:Short-acting bronchodilator puffs per week | - | Mean use of rescue medication ranged across from-9.99 to -0.10 puffs | Mean use of rescue medication was0.68 lower(3.63 lower to 2.28 higher) | 429(3) Low |
Date of latest search:30 January 2014
Primary/Secondary Keywords