Acute Effects of Low Temperature Exposure on Respiratory System

Acute Effects of Low Temperature Exposure on Respiratory Health in Healthy Young Adults: A Randomized Controlled Study

This is a randomized controlled human exposure crossover study. Investigators aims to assess the acute effects of low-temperature exposure on respiratory health and the underlying mechanisms.

Study Overview

• Status: Active, not recruiting
• Conditions: Lung Function
• Intervention / Treatment: Other: Moderate temperature (22°C) group; Other: Low temperature (15°C) group

Detailed Description

The investigators will conduct a randomized controlled human exposure crossover study among about 40 healthy young adults in Shanghai, China. Each subject will be exposed twice: once to the low temperature (15℃) and once to the moderate temperature (22℃) in a chamber for about 2 hours. During the exposure session, each subject will be requested to rest. Health examinations will be conducted immediately prior to exposure, during the period of exposure, and after exposure. Health examinations include lung function tests and exhaled breath test. Investigators plan to collect blood, pharyngeal secretion, exhaled breath condensate and urine samples.

• Study Type: Interventional
• Enrollment (Estimated): 40
• Phase: Not Applicable

Contacts and Locations

Study Locations

• China
  • Shanghai
    • Shanghai, Shanghai, China, 200032
      • Department of Environmental Health, School of Public Health, Fudan University

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Living in Shanghai during the study period;
• Body mass index > 18.5 and ≤ 28;
• right-handed;
• receiving or having received higher education;
• with the ability to read and understand Chinese smoothly.

Exclusion Criteria:

• Smoking and alcohol abuse;
• Current drug and dietary supplements intake;
• Subjects with allergic diseases, such as allergic rhinitis, allergic asthma, and atopy;
• Subjects with cardiovascular diseases, such as congenital heart disease, pulmonary heart disease, and hypertension;
• Subjects with respiratory diseases, such as asthma, chronic bronchitis, and chronic obstructive pulmonary disease;
• Subjects with chronic diseases, such as diabetes, chronic hepatitis, and kidney disease;
• Subjects who have a history of major surgery due to the cardiovascular, cerebrovascular, respiratory, or neurological diseases;
• Subjects with neurologic disorders, such as stroke, traumatic brain injury, epilepsy, and schizophrenia;
• Abnormal spirometry (FEV1 and FVC ≤ 75% of predicted and FEV1/FVC ≤ 0.65);
• Subjects with color vision disabilities.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Moderate temperature (22℃) group; Subjects in the exposure group will be exposed to moderate temperature (22℃) for about 2 hours in a chamber.	Other: Moderate temperature (22°C) group; The exposure group will be exposed to thermoneutral temperature (22°C) in a chamber for about 2 hours, resting during the whole periods.
Experimental: Low temperature (15℃) group; Subjects in the exposure group will be exposed to low temperature (15℃) for about 2 hours in a chamber.	Other: Low temperature (15°C) group; The exposure group will be exposed to low temperature (15°C) in a chamber for about 2 hours, resting during the whole periods.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Changes of forced expiratory volume in the first second (FEV1)	Investigators plan to measure the changes of the forced expiratory volume in 1 s (FEV1) using a smart spirometer (Model A1, BreathHome, China) supervised by professional medical staff. Before the pulmonary function test, subjects will practice several times by themselves. During the examination, each subject stands and clamps the nose clip, and repeats the test, with the best result as the criterion. FEV1 reflect pulmonary function.	The tests will be conducted at 12:30 A.M. (half an hour before exposure) and 3:30 P.M. (half an hour after the exposure)
Changes of forced vital capacity (FVC)	Investigators plan to measure the changes of forced vital capacity (FVC) using a portable spirometer (Jaeger Master screen V5.01; CareFusion). FVC reflects the expiratory resistance of large airways.	FVC will be examined at 12:30 A.M. (half an hour before exposure) and 3:30 P.M. (half an hour after the exposure)
Changes of peak expiratory flow rate (PEF)	Investigators plan to measure the changes of peak expiratory flow (PEF) using a portable spirometer (Jaeger Master screen V5.01; CareFusion). PEF reflects airway patency and respiratory muscle strength.	FVC will be examined at 12:30 A.M. (half an hour before exposure) and 3:30 P.M. (half an hour after the exposure)
Changes of maximum expiratory flow rate at 25% vital capacity (MEF25)	Investigators plan to measure the changes of maximum expiratory flow rate at 25% vital capacity. MEF25% reflects the early stage of expiratory flow rate.	MEF25 will be examined at 12:30 A.M. (half an hour before exposure) and 3:30 P.M. (half an hour after the exposure)
Changes of maximum expiratory flow rate at 50% vital capacity (MEF50)	Investigators plan to measure the changes of maximum expiratory flow rate at 50% vital capacity using a portable spirometer (Jaeger Master screen V5.01; CareFusion). MEF50 reflects the interim stage of expiratory flow rate.	MEF50 will be examined at 12:30 A.M. (half an hour before exposure) and 3:30 P.M. (half an hour after the exposure)
Changes of maximum expiratory flow rate at 75% vital capacity (MEF75)	Investigators plan to measure the changes of maximum expiratory flow rate at 50% vital capacity (MEF75%) using a portable spirometer (Jaeger Master screen V5.01; CareFusion). MEF75 reflects the terminal stage of expiratory flow rate.	MEF75 will be examined at 12:30 A.M. (half an hour before exposure) and 3:30 P.M. (half an hour after exposure)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Changes of fractional exhaled nitric oxide (FeNO)	Investigators plan to measure the changes of fractional exhaled nitric oxide using FeNO monitor (NIOX; Aerocrine AB, Solna, Sweden). FeNO reflects airway inflammation level	FeNO will be examined half an hour before exposure and half an hour after exposure
Changes of fractional concentration of carbon monoxide (FeCO)	Investigators plan to measure the changes of fractional concentration of carbon monoxide using Pico Smokerlyzer. FeCO reflects level of carboxyhemoglobin in blood.	FeCO will be examined at 12:30 A.M. (half an hour before exposure) and 3:30 P.M. (half an hour after the exposure)
Changes of skin temperature	The changes of wrist skin temperature will be measured	Wrist skin temperature will be measured at 1:00 P.M. to 3:00 P.M. on the day of the exposure session

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Differences in respiratory microbiota detected in pharyngeal secretion between the two exposures	differential respiratory microbiota in pharyngeal secretion related to low temperature exposure will be detected by integrating microbial 16S rRNA sequencing and non-targeted metabolomics.	Respiratory microbiota will be detected at 3:30 A.M. (half an hour after exposure) on the day of the exposure session
Differences in metabolic profiling detected in exhaled breath condensate between the two exposures	The differential metabolic profiling in exhaled breath condensate related to low temperature exposure will be detected by mass spectrometry-based non-targeted metabolomics.	Metabolic profiling in exhaled breath condensate will be detected at 4:00 P.M. (1 hour after the exposure session)
Differences in protein levels detected in blood Clara cell protein (CC16) between the two exposures	Investigators plan to measure the changes of Clara cell protein using enzyme linked immunosorbent assay (ELISA). Clara cell protein (CC16) indicate lung epithelial injury.	CC16 will be examined at 1:00 P.M. and 4:00 P.M. (one hour after the exposure) on the day of the exposure session
Differences in protein levels detected in blood chitinase-3-like protein 1 (YKL-40) between the two exposures	Investigators plan to measure the changes of chitinase-3-like protein 1 protein using enzyme linked immunosorbent assay (ELISA). YKL-40 represents airway inflammation and remodeling.	YKL-40 will be examined at 1:00 P.M. and 4:00 P.M. (one hour after exposure) on the day of the exposure session
Differences in protein levels detected in blood Surfactant Protein-D (SP-D) between the two exposures	Investigators plan to measure the changes of Surfactant Protein-D protein using enzyme linked immunosorbent assay (ELISA). SP-D represents pulmonary injury.	SP-D will be examined at 1:00 P.M. and 4:00 P.M. (one hour after exposure) on the day of the exposure session

Collaborators and Investigators

• Sponsor: Fudan University
• Investigators: Study Director: Haidong Kan, PhD, Fudan University

Study record dates

Study Major Dates

• Study Start (Actual): October 16, 2024
• Primary Completion (Actual): November 16, 2024
• Study Completion (Estimated): December 31, 2026

Study Registration Dates

• First Submitted: October 15, 2024
• First Submitted That Met QC Criteria: October 19, 2024
• First Posted (Actual): October 22, 2024

Study Record Updates

• Last Update Posted (Actual): March 25, 2025
• Last Update Submitted That Met QC Criteria: February 25, 2025
• Last Verified: February 1, 2025

More Information

Terms related to this study

• Keywords: Randomized controlled trial; Lung function; Low temperature
• Other Study ID Numbers: IRB#2024-10-1166

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