No association between temperature and deaths from cardiovascular and cerebrovascular diseases during the cold season in Astana, Kazakhstan--the second coldest capital in the world.

BACKGROUND: Several European and North American studies have reported associations between cold temperatures and mortality from diseases of the circulatory system. However, the effects of cold vary between the settings warranting further research in other parts of the world. OBJECTIVES: To study associations between temperature and mortality from selected diseases of circulatory system in Astana, Kazakhstan--the second coldest capital in the world. METHODS: Daily counts of deaths from hypertensive diseases (ICD-10 codes: I10-I15), ischemic heart disease (I20-I25) and cerebrovascular diseases (I60-I69) among adults 18 years and older in Astana, Kazakhstan, during cold periods (October-March) in 2000-2001 and 2006-2010 were collected from the City Registry Office. Associations between mortality and mean apparent temperature and minimum apparent temperature (average for lags 0-15) were studied using Poisson regression controlling for barometric pressure (average for lags 0-3), wind speed and effects of month, year, weekends and holidays. Analyses were repeated using mean and minimum temperatures. RESULTS: Overall, there were 320, 4468 and 2364 deaths from hypertensive disorders, ischemic heart disease and cerebrovascular diseases, respectively. No significant associations between either mean, mean apparent, minimum or minimum apparent temperatures were found for any of the studied outcomes. CONCLUSIONS: Contrary to the European findings, we did not find inverse associations between apparent temperatures and mortality from cardiovascular or cerebrovascular causes. Factors behind the lack of association may be similar to those in urban settings in Siberia, that is, centrally heated houses and a culture of wearing large volumes of winter clothes outdoors. Further research on the sensitivity of the population in Kazakhstan to climatic factors and its adaptive capacity is warranted.

Effect of high temperatures on daily counts of mortality from diseases of circulatory system in Astana, Kazakhstan.

BACKGROUND AND OBJECTIVE: Associations between hot temperatures and both overall and cardio- and cerebrovascular mortality have been observed in many European, North American, and Southeastern Asian cities. However, the effects varied among the settings with limited evidence from the countries with arid and semiarid climates. The aim of this study was to assess the effect of air temperature on deaths from the selected diseases of the circulatory system in the city of Astana, Kazakhstan. MATERIAL AND METHODS: The daily counts of deaths from hypertensive diseases (ICD-10 codes, I10-I15), cerebrovascular diseases (ICD-10 codes, I60-I69), and ischemic heart disease (ICD-10 codes, I20-I25) during the warm seasons (April-September) of 2000-2001 and 2006-2010 were obtained from the City Registry Office. The associations between the maximum apparent temperature (average of lags 0-3) and mortality were assessed by a first-order autoregressive Poisson regression with the adjustment for barometric pressure (average of lags 0-3), wind speed, and effects of month, year, holidays, and weekends. RESULTS: Altogether, there were 282, 1177, and 2994 deaths from hypertensive diseases, cerebrovascular diseases, and ischemic heart disease, respectively. The maximum effective temperature varied between -2.2°C and 44.5°C. An increase in temperature by 1°C was associated with a 1.9% (95% CI, 0.3-3.5) increase in the daily number of deaths from cerebrovascular diseases and with a 3.1% (95% CI, 0.2-6.1) decrease in the number of deaths from hypertensive diseases among women. CONCLUSIONS: The results suggest a positive association between the maximum apparent temperature and the daily counts of deaths from cerebrovascular diseases and an inverse association between temperature and mortality from hypertensive diseases, but only among women.