Influence Features of Cold and Heat Waves to the Population Mortality - The City With Sharply Continental Climate

Abstract

Цель исследования. Выбор наилучшего предиктора смертности во время волн жары и холода в условиях резко-континентального климата. Стратификация рисков смертности во время таких волн в Красноярске по основным причинам и возрастным группам для выявления основных температурных факторов повышенной смертности. Сравнение рисков с аналогичными результатами, полученными в южных городах России. Материал и методы. Метеоданные по 6 выбранным городам Сибири с резко-континентальным климатом получены с сайта Росгидромета. Для анализа воздействия продолжительных периодов экстремальных температур воздуха на смертность выбран Красноярск как крупнейший из изученных городов; данные о ежедневной смертности в Красноярске предоставлены Росстатом. Для вычисления относительных рисков смертности во время волн жары и холода использовалась Пуассоновская регрессионная модель суточной смертности с поправками на многолетние и сезонные тенденции смертности, день недели и суточный перепад температур.

Health Risks to the Russian Population from Temperature Extremes at the Beginning of the XXI Century

“…First, it was shown that heat (cold) waves were mainly defined as periods with abnormally high (low) temperatures compared to current values, often combined with high humidity (strong wind), which have an adverse effect on human body, expressed in a statistically significant increase in mortality or morbidity [69,71,72,[93][94][95][96][97][98][99][100][101][107][108][109][110][111]. Based on long-term research, it was determined that heat (cold) waves incorporate periods with an excess of the 97(3) % percentile of the distribution of mean daily temperature in the summer (winter) months [145,177].…”

“…When analyzing temperature waves, in addition to their duration, other indicators were described: the wave intensity, i.e. the sum of degrees above (below) the base temperature [72]; the "wave fraction" defined as the ratio of the number of days in the wave to the total number of days with temperatures above (below) the temperature threshold, for heat and cold waves, respectively [94,99]; the time shift between the beginning of the wave and the impact on the human body as the lagged effect [55,70,97,98,100,101]. In addition, increased (decreased) temperature background in summer (winter) [69,71,72,107] and air pollution [73,108] were analyzed, which contribute to the exacerbation of diseases during heat and cold waves.…”

“…The temperature thresholds for hot extremes in two cities of the Western Siberia (Barnaul and Kemerovo) and in four cities of the Eastern Siberia (Bratsk, Chita, Krasnoyarsk, Irkutsk) for the study period from 1999 to 2015 were homogeneous, varying in a narrow range from 21 to 23°C [98]. The longest heat wave (20 days) occurred in the summer of 1999 in Bratsk.…”

“…It was shown that short heat waves in northern cities had a stronger impact on mortality than long heat waves with the "harvesting effect" as a possible explanation. During long-term heat waves, excess mortality at the end of a long period with excessively hot temperatures was compensated by the "harvesting effect" -a short-term shift in mortality at the beginning of the wave [60,67,98,106,119]. The relative risk of mortality from cerebrovascular diseases, mainly strokes, was higher than from heart attacks, but the difference between these diseases was statistically insignificant.…”

“…In Krasnoyarsk, for the period from 1999 to 2015, only 10 waves with a duration of 5 or more days, defined by Apparent Temperature, were recorded, with a total duration of 91 days [98]. Excess mortality during heat waves in the age group of elderly (≥65) was 22% (95% CI: 17-28), mainly due to diseases of the circulatory system (hypertension, coronary heart disease).…”