RT Journal Article SR Electronic T1 Low-level laser therapy as a supplementary treatment in patients with moderate to severe persistent asthma JF European Respiratory Journal JO Eur Respir J FD European Respiratory Society SP P5096 VO 42 IS Suppl 57 A1 Arda Kiani A1 Hamidreza Jabbardarjani A1 Farid Azizi A1 Mohammad Fakhri YR 2013 UL http://erj.ersjournals.com/content/42/Suppl_57/P5096.abstract AB Background: Conventional medications for asthma can not affect peripheral and smaller airways of the respiratory tract because of the extension and unavailability of these airways. Low-level laser (LLL) therapy was introduced as a supplementary treatment option in managing the patients with moderate to severe persistent asthma.Methods: The study was a double-blind placebo controlled clinical trial. Patients were allocated to two groups; one group received medical treatment plus LLL as an add-on therapy, and the other group was managed with medical therapy with sham-LLL.Results: Thirty-three patients (26 female and 7 male) with a mean (SD) age of 46.2 (9.8) years with moderate to severe persistent asthma participated in the study. Patients were randomly assigned to two groups; intervention group (22 patients) and non-intervention group (11 patients). General linear model showed that mean FEV1 and PEF values differed significantly after LLL therapy between laser and placebo groups (p<0.002, p<0.0001 respectively). Paired samples t-test showed a significant difference in the mean values of FEV1 (p = 0.001) and PEF (p<0.0001) for pre-radiation and post-radiation values. Also, our findings also revealed that laser radiation caused a statistically significant reduction on asthma severity grade (p=0.004); number of medical visits (p<0.0001); daily symptoms (p<0.001) and nocturnal symptoms (p<0.0001) in the intervention group compared with the placebo group.Conclusions: Given the simplicity of use and acceptable efficacy, LLL can be considered as a complementary therapeutic option in combination with conventional asthma treatments in patients with mild to moderate symptoms.