Department of Neurology, Johann Wolfgang Goethe University, Frankfurt am Main, Germany.
Neuroepidemiology. 2010;35(3):226-30. doi: 10.1159/000319457. Epub 2010 Sep 23.
Gender differences in life expectancy result in a higher proportion of women in the older population. This causes a female preponderance among elderly patients with ischaemic stroke. On the other hand, upper age limits are frequently used in clinical trials, in part due to safety reasons and logistical concerns. In this study, we model how applying upper age limits will lead to a gender disparity in stroke trials, favouring the inclusion of men rather than women.
We analyzed a prospective hospital-based stroke registry covering the entire Federal State of Hesse, Germany. All cases with admission between 2003 and 2005 and a final diagnosis of ischaemic stroke (ICD10:I63) were selected. For various upper age limits (70, 75, 80, 85 and 90 years), we calculated the proportion of men and women excluded based on their age when applying the respective age span to the study population.
A total of 34,754 patients were analyzed, and 17,748 (51%) hereof were women. Their mean age was 73.6 ± 12.1 years. The women were older than the men (76.8 ± 11.7 years vs. 70.2 ± 11.7 years; p < 0.001). All upper age limits provoked a significant gender disparity by leaving a higher proportion of female than male patients outside the admissible range. In particular, selecting 80 years as the upper age cut-off excluded 19% of all male patients but 44% of all female patients (p < 0.001).
Setting an upper age limit for ischaemic stroke trials is likely not to be gender neutral but withholds a higher proportion of female than male patients from study participation. Investigators should be aware of such gender imbalances, which may involuntarily be transferred into routine clinical practice.
预期寿命的性别差异导致老年人口中女性比例较高。这导致患有缺血性中风的老年患者中女性比例偏高。另一方面，临床试验中经常使用上限年龄，部分原因是出于安全和后勤方面的考虑。在这项研究中，我们模拟了应用上限年龄将如何导致中风试验中的性别差异，偏向于纳入男性而不是女性。
我们分析了一个覆盖德国黑森州全境的前瞻性医院为基础的中风登记处。选择了 2003 年至 2005 年期间入院且最终诊断为缺血性中风（ICD10：I63）的所有病例。对于各种上限年龄（70、75、80、85 和 90 岁），我们根据年龄计算了根据各自年龄范围排除的男性和女性比例研究人群。
共分析了 34754 名患者，其中 17748 名（51%）为女性。她们的平均年龄为 73.6 ± 12.1 岁。女性比男性年龄大（76.8 ± 11.7 岁比 70.2 ± 11.7 岁；p < 0.001）。所有上限年龄都导致了显著的性别差异，使更多的女性患者被排除在可接受范围之外。特别是，选择 80 岁作为上限截止点，排除了所有男性患者的 19%，但排除了所有女性患者的 44%（p < 0.001）。
为缺血性中风试验设定上限年龄可能不是性别中立的，而是将更多的女性患者排除在研究参与之外。研究人员应该意识到这种性别不平衡，这可能会不自觉地转移到常规临床实践中。
