Iodinated glycerol has no effect on pulmonary function, symptom score, or sputum properties in patients with stable chronic bronchitis.

STUDY OBJECTIVE

It has been reported that therapy with iodinated glycerol (IG) can improve the quality of life for patients with chronic bronchitis. The purpose of this study was to determine the effects of IG therapy on the quality of life, pulmonary function, and on the properties of sputum collected from adults with stable chronic bronchitis.

DESIGN

Thirty-two week, double-blind, randomized, placebo-controlled cross-over study.

SETTING

A university outpatient pulmonary clinic.

PARTICIPANTS

Twenty-six adults with stable chronic bronchitis completed the study; 28 completed the first treatment arm.

INTERVENTIONS

Sixteen weeks each of placebo or IG 60 mg qid.

MEASUREMENTS

First, pulmonary function by spirometry and plethysmography. Second, symptom score measured using a questionnaire. Third, sputum bulk and surface rheology, spinnability, mucociliary transportability and cough transportability.

RESULTS

There were no significant changes in pulmonary function, clinical scores, or sputum properties related to therapy with IG. There was a significant improvement in the Global Petty score after both IG (p = 0.01) and placebo (p < 0.01) when compared with baseline, but there was no difference between treatment periods. There was a positive correlation between changes in the Global score during therapy and changes in sputum spinnability (p < 0.01, r = 0.38).

CONCLUSIONS

This study clearly demonstrates that in chronic bronchitis, 16 weeks of therapy with IG does not produce any appreciable effect on pulmonary function, well being, or on sputum viscoelasticity or clearability.