Andersson Therese M-L, Rutherford Mark J, Møller Bjørn, Lambert Paul C, Myklebust Tor Åge
Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden.
Biostatistics Research Group, Department of Health Sciences, University of Leicester, Leicester, United Kingdom.
Cancer Epidemiol Biomarkers Prev. 2022 Sep 2;31(9):1720-1726. doi: 10.1158/1055-9965.EPI-22-0137.
The loss in life expectancy, LLE, is defined as the difference in life expectancy between patients with cancer and that of the general population. It is a useful measure for summarizing the impact of a cancer diagnosis on an individual's life expectancy. However, it is less useful for making comparisons of cancer survival across groups or over time, because the LLE is influenced by both mortality due to cancer and other causes and the life expectancy in the general population.
We present an approach for making LLE estimates comparable across groups and over time by using reference expected mortality rates with flexible parametric relative survival models. The approach is illustrated by estimating temporal trends in LLE of patients with colon cancer in Sweden.
The life expectancy of Swedish patients with colon cancer has improved, but the LLE has not decreased to the same extent because the life expectancy in the general population has also increased. When using a fixed population and other-cause mortality, that is, a reference-adjusted approach, the LLE decreases over time. For example, using 2010 mortality rates as the reference, the LLE for females diagnosed at age 65 decreased from 11.3 if diagnosed in 1976 to 7.2 if diagnosed in 2010, and from 3.9 to 1.9 years for women 85 years old at diagnosis.
The reference-adjusted LLE is useful for making comparisons across calendar time, or groups, because differences in other-cause mortality are removed.
The reference-adjusted approach enhances the use of LLE as a comparative measure.
预期寿命损失（LLE）定义为癌症患者与普通人群预期寿命的差值。它是总结癌症诊断对个体预期寿命影响的一项有用指标。然而，它在比较不同群体或不同时期的癌症生存率时用处较小，因为预期寿命损失受癌症及其他原因导致的死亡率和普通人群预期寿命的双重影响。
我们提出一种方法，通过使用具有灵活参数相对生存模型的参考预期死亡率，使不同群体和不同时期的预期寿命损失估计具有可比性。通过估计瑞典结肠癌患者预期寿命损失的时间趋势来说明该方法。
瑞典结肠癌患者的预期寿命有所提高，但预期寿命损失并未以相同幅度下降，因为普通人群的预期寿命也有所增加。当使用固定人群和其他原因死亡率，即参考调整方法时，预期寿命损失随时间下降。例如，以2010年死亡率作为参考，65岁时被诊断出的女性患者的预期寿命损失，如果在1976年被诊断为11.3年，到2010年被诊断则降至7.2年；而诊断时85岁的女性患者的预期寿命损失从3.9年降至1.9年。
参考调整后的预期寿命损失在比较不同日历时间或不同群体时很有用，因为去除了其他原因死亡率的差异。
参考调整方法增强了预期寿命损失作为一种比较指标的用途。
