Effect of Smoking and Time of Day on Eosinophils

NCT07625111 | Recruiting

• 1 other identifier: Smoke-Time-Eosinophils
• Study Type: interventional
• Target: 20
• Locations: 1 country
• Sites: 1

Brief Summary

The study investigates the effect of acute smoking and time of day on blood eosinophils in chronic smokers. Chronic cigarette smokers without chronic respiratory diseases smoking at least 8 cigarettes per day and never-smoking controls are examined. Blood eosinophil counts and surface molecules are measured at 8 and 12 am in both groups. In smokers, two measurements are performed (at least 4 weeks apart): one measurement with no smoking between 8 and 12 am, and another measurement with smoking of 8 cigarettes between 8 and 12 am.

Conditions

Healthy

Keywords

Eosinophils; smoking; time of day; blood; flow cytometry

Outcome Measures

Primary Outcomes (1)

• Blood eosinophil counts

  Blood eosinophil counts in cells/µl blood

  8 am (baseline) and 12 am (follow-up after intervention)

Secondary Outcomes (1)

• Blood eosinophil surface molecules

  8 am (baseline) and 12 am (follow-up after intervention)

Study Arms (2)

A: Smoking of 8 cigarettes in 4 hours

EXPERIMENTAL

Smoking

Other: Smoking for 4 hours

B: No smoking for 4 hours

NO INTERVENTION

No Smoking

Interventions

Smoking for 4 hours OTHER

Smoking of 8 cigarettes in 4 hours

A: Smoking of 8 cigarettes in 4 hours

Eligibility Criteria

• Age: 18 Years - 50 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Healthy current smokers
• Age between 18-50 years
• Smoking of at least 8 cigarettes/day

You may not qualify if:

• Chronic respiratory diseases
• Any treatment with corticosteroids or other immunosuppressants
• Any acute illness

Sponsors & Collaborators

• Marek Lommatzsch: lead

Study Sites (1)

University of Rostock

Rostock, 18057, Germany

RECRUITING

MeSH Terms

Conditions

Smoking

Interventions

Smoking Devices

Condition Hierarchy (Ancestors)

Behavior

Intervention Hierarchy (Ancestors)

Manufactured Materials; Technology, Industry, and Agriculture

Central Study Contacts

Marek Prof. Lommatzsch, Prof.

CONTACT

+49-381-494-7461; marek.lommatzsch@med.uni-rostock.de

Johann C. Virchow, Prof.

CONTACT

+49-381-494-7461

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: BASIC SCIENCE
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: SPONSOR INVESTIGATOR
• PI Title: Prof. Dr. Marek Lommatzsch

Model Details: Intervention: Smoking. Intervention: Time of day.

Study Record Dates

• First Submitted: May 26, 2026
• First Posted: June 4, 2026
• Study Start: February 7, 2026
• Primary Completion: June 30, 2026
• Study Completion (Estimated): December 6, 2026
• Last Updated: June 4, 2026

Record last verified: 2026-06

Data Sharing

• IPD Sharing: Will not share

Locations

DE (1)