Dependence of cold-related coronary and respiratory symptoms on age and exposure to cold.

Cold causes cardiopulmonary stress often perceived as shortness of breath or chest pain, and causes exacerbation of these symptoms in persons suffering heart or lung disease. We investigated the prevalence of these symptoms and their association with sex, age and cold exposure in a population-based sample of 1,785 persons who lived in three areas of Finland. The exposure to cold was measured by the annual number cold days (mean daily temperature below 0 degree C) in the resident locality and weekly hours spent in the cold in winter. Shortness of breath was 25% and chest pain 52% more common in females than in males, and their prevalence increased by 24% and 77%, respectively, for every 10 years of age. The prevalence of shortness of breath increased by 5% and chest pain by 6% for every 10 cold days in the resident locality, and by 6% and 7% for every 10 hours spent in the cold, respectively. We suggest that environmental cold, measured by the number of cold days throughout the year and weekly hours spent in the cold, may provoke cardiopulmonary symptoms independent of sex and age.