Supplementary Material for: Disparities in Chronic Kidney Disease Prevalence among Males and Females in 195 Countries: Analysis of the Global Burden of Disease 2016 Study

Background: Chronic kidney disease (CKD) imposes a substantial burden on health care systems. There are some especially vulnerable groups with a high CKD burden, one of which is women. We performed an analysis of gender disparities in the prevalence of all CKD stages and renal replacement therapy (defined as impaired kidney function [IKF]) in 195 countries. Methods: We used estimates produced by the Global Burden of Disease (GBD) Study 2016 revision using a Bayesian-regression analytic tool, DisMoD-MR 2.1. Data on gross domestic product based on purchasing power parity per capita (GDP PPP) was obtained via the World Bank International Comparison Program database. To estimate gender disparities, we calculated the male:female all-age prevalence rate ratio for each IKF condition. Results: In 2016, the global number of individuals with IKF reached 752.7 million, including 417.0 million females and 335.7 million males. The most prevalent form of IKF in both groups was albuminuria with preserved glomerular filtration rate. Geospatial analysis shows a very heterogeneous distribution of the male:female ratio for all IKF conditions, with the most prominent contrast found in kidney transplant patients. The median male:female ratio varies substantially according to GDP PPP quintiles; however, countries with different economic states could have similar male:female ratios. A strong correlation of GDP PPP with dialysis-to-transplant ratio was found. Conclusions: The GBD study highlights the prominent gender disparities in CKD prevalence among 195 countries. The nature of these disparities, however, is complex and must be interpreted cautiously taking into account all possible circumstances.背景：慢性肾脏病（Chronic kidney disease, CKD）给全球医疗卫生系统带来了沉重负担。存在若干CKD负担沉重的特殊脆弱群体，其中女性群体便是其一。本研究针对195个国家的全分期慢性肾脏病及以肾功能受损（impaired kidney function, IKF）定义的肾脏替代治疗的患病率性别差异展开分析。 方法：本研究采用全球疾病负担（Global Burden of Disease, GBD）2016修订版通过贝叶斯回归分析工具DisMod-MR 2.1生成的估算数据集。以购买力平价计算的人均国内生产总值（gross domestic product based on purchasing power parity per capita, GDP PPP）数据来源于世界银行国际比较项目（World Bank International Comparison Program）数据库。为评估性别差异，我们针对每一类肾功能受损病症，计算了其男性与全年龄段女性的患病率比值。 结果：2016年，全球肾功能受损患者总规模达7.527亿，其中女性4.170亿，男性3.357亿。两类人群中患病率最高的肾功能受损类型均为肾小球滤过率保留的白蛋白尿。地理空间分析显示，所有肾功能受损病症的男女性患病率比值分布异质性极强，其中肾移植患者群体的性别比值差异最为显著。按人均购买力平价国内生产总值五分位组划分，男女性患病率中位数比值存在显著差异；但不同经济发展水平的国家，其男女性患病率比值可能趋于相近。研究同时发现，人均购买力平价国内生产总值与透析-移植比值存在强相关性。 结论：全球疾病负担研究凸显了195个国家中慢性肾脏病患病率存在显著的性别差异。然而此类差异的形成机制复杂，需结合所有潜在影响因素谨慎解读。