Department of Internal Medicine, University of Manitoba, 820 Sherbrook Street, Winnipeg, MB, R3A1R9, Canada.
Department of Community Health Sciences, University of Manitoba, Room S113, 750 Bannatyne Avenue, Winnipeg, MB, R3E0W3, Canada.
Crit Care. 2018 Aug 20;22(1):208. doi: 10.1186/s13054-018-2132-8.
The consistently observed male predominance of patients in intensive care units (ICUs) has raised concerns about gender-based disparities in ICU access. Comparing rates of ICU admission requires choosing a normalizing factor (denominator), and the denominator usually used to compare such rates between subpopulations is the size of those subpopulations. However, the appropriate denominator is the number of people whose medical condition warranted ICU care. We devised an estimate of the number of critically ill people in the general population, and used it to compare rates of ICU admission by gender and income.
This population-based, retrospective analysis included all adults in the Canadian province of Manitoba, 2004-2015. We created an estimate for the number of critically ill people who warrant ICU care, and used it as the denominator to generate critical illness-normalized rates of ICU admission. These were compared to the usual population-normalized rates of ICU care.
Men outnumbered women in ICUs for all age groups; population-normalized male:female rate ratios significantly exceed 0 for every age group, ranging from 1.15 to 2.10. Using critical-illness normalized rates, this male predominance largely disappeared; critically ill men and women aged 45-74 years were admitted in equivalent proportions (critical-illness normalized rate ratios 0.96-1.01). While population-normalized rates of ICU care were higher in lower income strata (p < 0.001), the gradient for critical illness-based rates was reversed (p < 0.001).
Across a 30-year adult age span, the male predominance of ICU patients was accounted for by higher estimated rates of critical illness among men. People in lower income strata had lower critical-illness normalized rates of ICU admission. Our methods highlight that correct inferences about access to healthcare require calculating rates using denominators appropriate for this purpose.
重症监护病房（ICU）中患者持续存在的男性优势引起了人们对 ICU 获得机会方面性别差异的关注。比较 ICU 入院率需要选择一个规范化因素（分母），通常用于比较亚人群之间此类比率的分母是这些亚人群的规模。然而，适当的分母是那些医疗状况需要 ICU 护理的人数。我们设计了一种估计普通人群中危重症患者数量的方法，并使用该方法比较了男女和收入对 ICU 入院率的影响。
这是一项基于人群的回顾性分析，包括加拿大马尼托巴省 2004 年至 2015 年所有成年人。我们创建了一个估计需要 ICU 护理的危重症患者数量的方法，并将其作为分母来生成 ICU 入院的危重症标准化率。这些比率与通常的人口标准化 ICU 护理率进行了比较。
在所有年龄段，男性在 ICU 中的人数都超过了女性；每个年龄段的人口标准化男性：女性比率都显著大于 0，范围从 1.15 到 2.10。使用危重症标准化率，这种男性优势在很大程度上消失了；45-74 岁的危重症男女患者的入院比例相当（危重症标准化率比值为 0.96-1.01）。虽然较低收入阶层的 ICU 护理人口标准化率较高（p<0.001），但基于危重症的比率梯度则相反（p<0.001）。
在 30 年的成年年龄范围内，ICU 患者的男性优势归因于男性中更高的危重症估计发生率。收入较低阶层的人 ICU 入院的危重症标准化率较低。我们的方法强调，正确推断医疗保健的获得需要使用适当的分母来计算比率。
