Department of Health, South Australia, 11 Hindmarsh Square Adelaide, South Australia 5000, Australia.
Environ Health. 2011 May 19;10:42. doi: 10.1186/1476-069X-10-42.
Extreme heatwaves occurred in Adelaide, South Australia, in the summers of 2008 and 2009. Both heatwaves were unique in terms of their duration (15 days and 13 days respectively), and the 2009 heatwave was also remarkable in its intensity with a maximum temperature reaching 45.7 °C. It is of interest to compare the health impacts of these two unprecedented heatwaves with those of previous heatwaves in Adelaide.
Using case-series analysis, daily morbidity and mortality rates during heatwaves (≥ 35 °C for three or more days) occurring in 2008 and 2009 and previous heatwaves occurring between 1993 and 2008 were compared with rates during all non-heatwave days (1 October to 31 March). Incidence rate ratios (IRRs) were established for ambulance call-outs, hospital admissions, emergency department presentations and mortality. Dose response effects of heatwave duration and intensity were examined.
Ambulance call-outs during the extreme 2008 and 2009 events were increased by 10% and 16% respectively compared to 4.4% during previous heatwaves. Overall increases in hospital and emergency settings were marginal, except for emergency department presentations in 2008, but increases in specific health categories were observed. Renal morbidity in the elderly was increased during both heatwaves. During the 2009 heatwave, direct heat-related admissions increased up to 14-fold compared to a three-fold increase seen during the 2008 event and during previous heatwaves. In 2009, marked increases in ischaemic heart disease were seen in the 15-64 year age group. Only the 2009 heatwave was associated with considerable increases in total mortality that particularly affected the 15-64 year age group (1.37; 95% CI, 1.09, 1.71), while older age groups were unaffected. Significant dose-response relationships were observed for heatwave duration (ambulance, hospital and emergency setting) and intensity (ambulance and mortality).
While only incremental increases in morbidity and mortality above previous findings occurred in 2008, health impacts of the 2009 heatwave stand out. These findings send a signal that the intense and long 2009 heatwave may have exceeded the capacity of the population to cope. It is important that risk factors contributing to the adverse health outcomes are investigated to further improve preventive strategies.
2008 年和 2009 年夏季，南澳大利亚州阿德莱德遭遇极端热浪。这两次热浪在持续时间（分别为 15 天和 13 天）方面均较为独特，而 2009 年热浪的强度也很显著，最高温度达到 45.7°C。因此，将这两次前所未有的热浪与阿德莱德以前的热浪进行健康影响比较是很有意义的。
使用病例系列分析，比较了 2008 年和 2009 年发生的（持续三天或以上，温度达到 35°C 或以上）热浪期间与 1993 年至 2008 年期间以前热浪期间以及所有非热浪日（10 月 1 日至 3 月 31 日）的每日发病率和死亡率。确定了救护车出动、住院、急诊就诊和死亡率的发病率比值（IRR）。还检查了热浪持续时间和强度的剂量反应效应。
与以前的热浪相比，2008 年和 2009 年极端热浪期间的救护车出动量分别增加了 10%和 16%。除了 2008 年的急诊就诊量有所增加外，医院和急诊就诊量的总体增加幅度较小，但观察到特定健康类别的增加。老年人的肾脏发病率在两次热浪期间均有所增加。在 2009 年热浪期间，直接与热有关的住院人数增加了 14 倍，而在 2008 年事件和以前的热浪期间增加了 3 倍。在 2009 年，15-64 岁年龄组的缺血性心脏病显著增加。只有 2009 年的热浪与总死亡率的显著增加有关，这尤其影响了 15-64 岁年龄组（1.37；95%CI，1.09，1.71），而老年人群不受影响。还观察到了热浪持续时间（救护车、医院和急诊就诊）和强度（救护车和死亡率）的显著剂量反应关系。
虽然 2008 年的发病率和死亡率仅比以前的发现略有增加，但 2009 年热浪的健康影响却引人注目。这些发现表明，2009 年强度大且持续时间长的热浪可能已经超出了人口的应对能力。重要的是，要调查导致不良健康结果的危险因素，以进一步改进预防策略。
