SAW Lung Microbiome Study in Smokers and Never-smokers

Leibniz Association Senate Board of Competition (SAW) Lung Microbiome Study

The trial aims to analyse changes in the microbiome of the lower airways after smoking cessation. Microbiome analyses (upper airway swabs, bronchoalveolar lavage, transbronchial brushing) are conducted in smokers before and 6 weeks after smoking cessation. Never smokers serve as a control group and undergo the same sampling procedures once.

Study Overview

• Status: Completed
• Conditions: Smoking Cessation; Healthy; Microbial Colonization; Chronic Obstructive Pulmonary Disease (COPD)
• Intervention / Treatment: Behavioral: Smoking cessation

Detailed Description

The trial aims to analyze changes in the microbiome of the lower airways after smoking cessation. Microbiome analyses (upper airway swabs, bronchoalveolar lavage, transbronchial brushing) are conducted in healthy (and willing to quit) smokers before and 6 weeks after smoking cessation. Never smokers serve as a control group and undergo the same sampling procedures once.

Demographic and clinical data of the study subjects are obtained, aiming for homogeneous groups. All personal data are encrypted according to the standard operating procedures of the study site. Pharyngeal and deep nasal swabs are taken.

To avoid contamination of the lower airways from the oropharynx through the bronchoscope, standardized procedures are established according to the German guidelines for bronchoscopy. Before bronchoscopy, the endoscope is flushed with sterile saline which is analyzed for 16S ribosomal RNA (rRNA) to control for residual contaminating bacterial desoxyribonucleic acid (DNA). A 300ml bronchoalveolar lavage with warm normal saline solution is taken from the middle lobe. Three covered and "microbiologically protected" bronchial brushings are obtained from the right upper lobe. This sterile brush is sealed in wax and pushed through the wax just before taking the brushing. All samples are immediately frozen and stored at -80°C until further analyses. For cultivations, samples are kept at 4°C and rapidly processed.

• Study Type: Interventional
• Enrollment (Actual): 60
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Germany
  • Schleswig-Holstein
    • Borstel, Schleswig-Holstein, Germany, 23845
      • Research Center Borstel

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Cigarette consumption of at least five cigarettes per day
• Caucasian ethnicity

Exclusion Criteria:

• Continous passive smoking exposure
• Systemic steroid therapy during the previous month
• Chronic lung disease (exception COPD stage Global Initiative on Lung Disease (GOLD) 0/I/II)
• Diabetes mellitus
• Pregnancy or breast feeding
• active tuberculosis (currently or previously)
• respiratory infection in the previous month
• antibiotic therapy in the previous two months
• immunosuppression
• malignancy
• interstitial lung disease
• rheumatic disease with lung manifestation
• member of a collaborative group of the project

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Non-Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Smokers; Healthy caucasian smokers who are willing to quit smoking are investigated before cessation (Visit 1) and 6 weeks after cessation (Visit 2). Intervention: Smoking cessation	Behavioral: Smoking cessation; Smoking cessation with or without professional / medical support
No Intervention: Never-Smokers; Healthy caucasian volunteers who never smoked are investigated once only (Visit 1)

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in microbiome pattern in smokers after smoking cessation	Number of bacteria genera in the lung identified by 16S rRNA and bacterial culture	6 Weeks

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Smoking cessation rates	Percentage of sustained smoking cessation	6 weeks
Smoking cessation rates	Percentage of sustained smoking cessation	6 months
Lung microbiome in never-smokers	Number of bacteria genera in the lung identified by 16S rRNA and bacterial culture	0 days

Collaborators and Investigators

• Sponsor: Research Center Borstel
• Collaborators: Leibniz Institute DSMZ - German Collection of Microorganisms and Cell Cultures; Leibniz Institute of Photonic Technology (IPHT), Jena, Germany; Technical University of Munich, Helmholtz Center Munich, Munich Germany

Publications and helpful links

General Publications

• Pfeiffer S, Herzmann C, Gaede KI, Kovacevic D, Krauss-Etschmann S, Schloter M. Different responses of the oral, nasal and lung microbiomes to cigarette smoke. Thorax. 2022 Feb;77(2):191-195. doi: 10.1136/thoraxjnl-2020-216153. Epub 2021 Aug 13.

Study record dates

Study Major Dates

• Study Start (Actual): March 29, 2017
• Primary Completion (Actual): December 31, 2019
• Study Completion (Actual): March 1, 2020

Study Registration Dates

• First Submitted: May 26, 2018
• First Submitted That Met QC Criteria: June 7, 2018
• First Posted (Actual): June 19, 2018

Study Record Updates

• Last Update Posted (Actual): April 17, 2024
• Last Update Submitted That Met QC Criteria: April 15, 2024
• Last Verified: April 1, 2024

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Pathologic Processes; Respiratory Tract Diseases; Lung Diseases; Disease Attributes; Chronic Disease; Lung Diseases, Obstructive; Pulmonary Disease, Chronic Obstructive; Infections; Communicable Diseases
• Other Study ID Numbers: SAW Lungenmikrobiom-Studie

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No