Low-level laser therapy in chronic obstructive lung disease

Chronic obstuctive lung disease (COPD) is a common preventable and treatable disease. Low-level laser therapy (LLLT) appears to be a promising modality in COPD management. The aim was to study the short-term effects of LLLT on clinical and cardiac status in patients with stable COPD. This was a controlled randomized study. Patients with impaired left ventricular ejection fraction less than 50%, those with atrial fibrillation (AF), those with pulmonary hypertension not owing to COPD, and those with any contraindication to exercise test or LLLT were excluded. A total of 30 patients with stable COPD were divided into laser and control groups (15 patients each). Medical treatment was optimized in both groups with the addition of LLLT in the laser group. The following were assessed before and after LLLT: Modified Medical Research Council (mMRC) scale, 6 min walk test, tricuspid annular plane systolic excursion, and lateral tricuspid annulus tissue Doppler velocities. The LLLT has wavelength of 905 nm, output of 5–20mW, and frequency of 500 Hz. Laser probe was placed on intercostal space both anteriorly and posteriorly on chest wall and arm with standardized laser acupuncture points of application with a frequency of five sessions/week for 2 successive weeks. Statistical package for the social sciences Software program, version 21 (SPSS). Data were summarized using range, mean, SD, and median for quantitative variables and frequency and percentage for qualitative ones. Comparison between groups was performed using independent sample t-test (if parametric) or Mann–Whitney test (if nonparametric) for quantitative variables and χ2-test or Fisher’s exact test for qualitative ones. Paired quantitative measures were evaluated using paired t-test (if parametric) or Wilcoxon test (if nonparametric). P values less than 0.05 were considered statistically significant, and less than 0.01 were considered highly significant. Patients in LLLT group had higher pulmonary artery systolic pressure, lower early (E′) and higher late (A′) lateral tricuspid annular velocities by Tissue Doppler echocardiography (TDE) versus control. Overall, 100% of laser patients showed improvement in mMRC scale by at least one grade versus 46% in control. In laser group, 6 min walk test was 24.4±10.4 before versus 52.9±14.7m at the end of the study (P=0.001). In control, it was 32.4±14.9 versus 40.1±19.2, (P=0.003). No echocardiographic changes were noticed before versus after the study. Significant clinical improvement of 6 min walk test and mMRC scale grading after LLLT therapy was observed. No detrimental effects of LLLT on left ventricle or right ventricle functions or pulmonary artery systolic pressure were seen.