A Case-crossover Study: The Effects of Heat Waves on Daily Mortality Caused by Respiratory Disease in Beijing

Abstract

PP-31-083 Background/Aims: To explore the effects of heat wave on daily mortality caused by respiratory disease in Beijing from 1 January, 1999 to 30 June, 2000, and to analyze the effect on death of chronic obstructive pulmonary disease (COPD). Methods: Symmetrical bi-directional control case-crossover design was used to study the impact. The seventh day before and after death were chosen as its own self-control. Results: There were significant effects on daily death counts on people suffering from the first, second, and third heat waves. The lag phase was 2–5 days. The OR values of daily death from respiratory disease for 5 heat wave events were 2.124 (95% CI: 1.643–2.746), 2.143 (95% CI: 1.034–4.439), 3.733 (95% CI: 2.890–4.823), 1.067 (95% CI: 0.452–2.516), and 1.091 (95% CI: 0.401–2.950), respectively. The OR values for COPD were 1.620 (95% CI: 1.165–2.253), 2.222 (95% CI: 0.903–5.469), 2.947 (95% CI: 2.106–4.126), 1.000 (95% CI: 0.342–2.926), and 1.500 (95% CI: 0.632–3.560), respectively. The OR values of women's daily death counts caused by respiratory disease were 3.300 (95% CI: 2.001–5.442) and 4.326 (95% CI: 3.013–6.209) for the first and the third heat wave events, respectively, which were higher than that of men's 2.080 (95% CI: 1.291–3.351) and 3.149 (95% CI: 2.185–4.539), respectively. The OR values of daily death counts for individuals aged ≥65 years were 2.846 (95% CI: 1.976–4.099) and 3.753 (95% CI: 2.866–4.915), whereas the OR values of those aged <65 years were 1.167 (95% CI: 0.392–3.471) and 3.333 (95% CI: 1.459–7.617), respectively. The results indicated that the impact of heat wave event on elderly women (≥65 years) was greater than other subpopulation. The OR values were 2.909 (95% CI: 1.982–4.270) for the first and 4.474 (95% CI: 3.052–6.558) for the third heat wave. Conclusion: (1) There was a significant increase in daily death counts as a result of respiratory disease, including COPD, in Beijing, in individuals suffering from the heat wave. The lag phase was 2–5 days. (2) In women, the risk of daily death for women caused by respiratory disease was greater than in men during heat wave. (3) The risk of respiratory disease death for elderly residents was greater, and the effect of heat wave on elderly females was the maximum.