Description Module
The Description Module contains narrative descriptions of the clinical trial, including a brief summary and detailed description. These descriptions provide important information about the study's purpose, methodology, and key details in language accessible to both researchers and the general public.
Description Module path is as follows:
Study -> Protocol Section -> Description Module
Description Module
Ignite Creation Date:
2025-12-25 @ 2:23 AM
Ignite Modification Date:
2025-12-25 @ 2:23 AM
NCT ID:
NCT00468234
Brief Summary:
This study will evaluate biomarkers measured in exhaled breath condensate (EBC) to assess clinical strategies of harm reduction. It will take advantage of a recently developed device that permits collection of exhaled breath condensate reproducibly, with minimal subject effort and with no oral contamination. Samples from asymptomatic smokers before and after inducing a change in their smoking habit (cessation or reduction) with the aid of partial nicotine replacement.
Detailed Description:
The proposed study will evaluate biomarkers measured in exhaled breath condensate (EBC) for the purpose of assessing clinical strategies of harm reduction. It will take advantage of a recently developed device that permits collection of exhaled breath condensate reproducibly, with minimal subject effort and with no oral contamination. The major goal of the trial is to provide evidence to validate biomarkers in EBC.
This will be accomplished by collecting samples from asymptomatic smokers before and after inducing a change in their smoking habit (cessation or reduction) with the aid of partial nicotine replacement.
Measures to be made in EBC include H2O2, the most widely explored biomarker in this "body" fluid. Methods that reliably can quantify levels in normal non-smokers and in asymptomatic smokers will be used. Two fold increases in smokers have been reported by in several reports and confirmed in preliminary data by the investigators. In addition, other biomarkers of oxidant stress: TBARs, 8-isoprostane and nitrotyrosine will be quantified using standard methods.
Biomarkers quantified in EBC will be assessed for reliability (i.e. reproducibility and for sensitivity) to change and for validity (by comparison to clinically defined endpoints and previously validated measures of exposure). Reproducibility will be assessed by making repeated measurements in the same subjects on different occasions. Sensitivity to change will be assessed by comparing values before and after changing smoking habit. Finally, the validity of the biomarkers will be assessed by comparing them to previous measures of smoke exposure (CO, NNAL and NNAL-glc) and to clinically defined endpoints: symptoms, the St. George's Respiratory Questionnaire and post bronchodilator lung function. With regard to the latter measures, preliminary data indicate that symptoms can be detected in "asymptomatic" smokers and that these can change with a harm reduction strategy.
Study:
NCT00468234
Study Brief:
Protocol Section:
NCT00468234