Cold--an underrated risk factor for health

Area of Science:

• Environmental Health
• Epidemiology
• Cardiology

Background:

• Cardiovascular diseases (CVD) cause 20% of global deaths and 50% in developed nations.
• Excess winter mortality, a rise in deaths during colder months, is a documented phenomenon.
• CVD accounts for a significant portion of excess winter deaths, with respiratory diseases also contributing.

Purpose of the Study:

• To investigate the phenomenon of excess winter mortality, specifically its link to cardiovascular diseases.
• To explore the paradoxical increase in CVD mortality with falling temperatures, even in regions with mild winters.
• To elucidate the unclear mechanisms connecting cold ambient conditions to increased mortality risk.

Main Methods:

• The study reviews epidemiological evidence linking cold climates to increased mortality rates.
• It considers both outdoor and indoor climatic conditions as potential factors.
• It examines contributing factors such as health status, thermoregulation, toxicology, and socioeconomic status.

Main Results:

• Seasonal variations in death rates are observed, with peaks during winter months.
• CVD mortality shows a disproportionate increase with temperature drops, notably in areas with warmer winters.
• Indirect evidence suggests cold exposure, potentially indoor, is linked to excess winter deaths.

Conclusions:

• Cold exposure is strongly implicated in excess winter mortality, particularly for cardiovascular diseases.
• The precise mechanisms remain unclear but may involve indoor environmental factors and individual health determinants.
• Further research is needed to understand how mild cold exposure increases mortality risk.