Simón Méndez Lorena, López-Cuadrado Teresa, López Perea Noemí, Larrauri Cámara Amparo, de Mateo Ontañón Salvador
Centro Nacional de Epidemiología, Instituto de Salud Carlos III, Madrid, España.
Rev Esp Salud Publica. 2012 Mar-Apr;86(2):153-63. doi: 10.1590/S1135-57272012000200004.
The indicator of Potential Years of Life Lost (PYLL) has been frequently used to analysis of premature mortality and recently has been used to estimate the impact of the last influenza A(H1N1)pdm09 pandemic. The aim of this study was to estimate the excess deaths from pneumonia and influenza (P&I) in Spain and the PYLL during the period 1980-2008, measuring the mortality attributable to influenza regarding the type/subtype of influenza dominant in each season.
Monthly excess deaths were calculated with cyclical regression models. The PYLL calculation was performed as the product of the number of excess deaths and the difference between life expectancy at birth and years lived for each age group. The analysis of the variation between P&I excess deaths and PYLL, depending on the predominant influenza virus type/subtype was carried out with a Poisson regression analysis.
In seasons dominated by influenza virus A(H3) the average P&I excess deaths was estimated at 1,348, and for PYLL in 5.297, while in seasons dominated by A(H1) or B the average P&I excess deaths was 648, and for PYLL 2.885. The adjusted rate ratios of excess (2.11, CI-95%=2.05-2.16) and PYLL (1.86, CI-95%=1.83-1.88) indicate that the relative frequencies for both indicators are significantly larger in seasons dominated by influenza virus A(H3).
Excess deaths and PYLL doubled when comparing seasons predominantly subtype A(H3) and other influenza viruses.
潜在寿命损失年数（PYLL）指标经常被用于分析过早死亡情况，最近还被用于估计2009年甲型H1N1流感大流行的影响。本研究的目的是估算1980 - 2008年期间西班牙肺炎和流感（P&I）导致的超额死亡人数以及PYLL，根据每个季节占主导地位的流感类型/亚型来衡量流感所致的死亡率。
采用周期性回归模型计算每月的超额死亡人数。PYLL的计算方法是超额死亡人数与每个年龄组出生时预期寿命与已存活年数之差的乘积。采用泊松回归分析，根据占主导地位的流感病毒类型/亚型，对P&I超额死亡人数和PYLL之间的差异进行分析。
在以甲型（H3）流感病毒为主导的季节中，P&I平均超额死亡人数估计为1348人，PYLL为5297人；而在以甲型（H1）或乙型流感为主导的季节中，P&I平均超额死亡人数为648人，PYLL为2885人。超额死亡（2.11，95%置信区间=2.05 - 2.16）和PYLL（1.86，95%置信区间=1.83 - 1.88）的调整率比表明，在以甲型（H3）流感病毒为主导的季节中，这两个指标的相对频率显著更高。
将以甲型（H3）为主导的季节与其他流感病毒季节相比较，超额死亡人数和PYLL增加了一倍。
