Respiratory changes due to extreme cold in the Arctic environment

Area of Science:

• Environmental Physiology
• Respiratory Medicine

Background:

• Cold stress significantly impacts physiological functions, particularly in individuals not adapted to cold environments.
• Understanding respiratory adaptations to cold is crucial for populations living or working in extreme climates.

Purpose of the Study:

• To investigate the effects of acute cold exposure and subsequent acclimatization on respiratory functions in healthy tropical Indian men.
• To compare the respiratory responses of Indian men with Russian natives and migrants in an arctic environment.

Main Methods:

• Respiratory functions including vital capacity (VC), forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), peak expiratory flow rate (PEFR), and maximum voluntary ventilation (MVV) were measured.
• Measurements were taken at baseline in India, serially in the arctic region over 9 weeks, and upon return to India.
• Comparative data were collected from Russian migrants (RM) and Russian natives (RN).

Main Results:

• Acute cold exposure initially decreased VC, FVC, FEV1, PEFR, and MVV in Indian men.
• Acclimatization over 4-9 weeks led to gradual recovery and significant improvement in these parameters.
• Russian natives showed improved respiratory function after 10 weeks in the arctic, unlike Russian migrants.

Conclusions:

• Respiratory functions in tropical individuals adapt to cold stress through acclimatization, showing initial decline followed by improvement.
• The physiological responses to acute cold exposure share similarities with initial responses to altitude exposure.
• Long-term cold acclimatization may differ between native and migrant populations.