Epidemiology of immune thrombocytopenia in Yunnan Province and cytokine expression characteristics at different altitudes

Primary immune thrombocytopenia (ITP) is an autoimmune hemorrhagic disorder characterized by low platelet counts. Currently, the epidemiology of ITP in China remains poorly understood. A cross-sectional study was conducted to analyze data from newly diagnosed ITP patients in Yunnan Province from 2022 to 2023 to assess the epidemiological characteristics of ITP. Enzyme linked immunosorbent assay (ELISA) were conducted to detect plasma cytokine levels in ITP patients and healthy controls from two different altitude regions. This study reports for the first time an average incidence rate of 6.75 per 100,000 population for ITP in Yunnan Province, China. There was a significant difference in incidence rates between males and females, at 5.9 and 7.59, respectively. Infants under the age of 4 were identified as having the highest risk of ITP. After age 70, the incidence in males began to exceed that in females. This is different from previous reports in Japan, Europe and the United States. Additionally, there was no significant difference in the incidence of ITP based on altitude; however, mid-latitude regions had a higher concentration of ITP patients. Cytokine analysis was performed in 88 individuals, revealing significantly elevated Hypoxia-inducible factor alpha (HIF-1α) and Interleukin (IL-4) levels in ITP patients from high-altitude regions. This study offers the first insights into the epidemiological characteristics of ITP in Yunnan Province and underscores the impact of altitude on cytokine variations in ITP patients. These findings offer valuable guidance for personalized treatment strategies and the formulation of public health policies for ITP.

原发性免疫性血小板减少症（Primary immune thrombocytopenia, ITP）是一种以血小板计数降低为特征的自身免疫性出血性疾病。目前，中国境内ITP的流行病学特征仍有待深入阐明。本研究开展一项横断面研究，分析2022至2023年云南省新诊断ITP患者的相关数据，以评估ITP的流行病学特点。研究采用酶联免疫吸附试验（Enzyme linked immunosorbent assay, ELISA），检测来自两个不同海拔区域的ITP患者与健康对照者的血浆细胞因子水平。本研究首次报道了中国云南省ITP的平均发病率为6.75/10万人口；男女发病率存在显著统计学差异，分别为每10万人口5.9和7.59。4岁以下婴幼儿被鉴定为ITP发病风险最高的人群。70岁以后，男性ITP发病率开始超过女性，这与此前日本、欧美地区的相关报道存在差异。此外，按海拔划分的ITP发病率并无显著统计学差异，但中纬度区域的ITP患者分布更为集中。本研究对88名受试者开展细胞因子分析，结果显示高海拔区域的ITP患者体内缺氧诱导因子-α（Hypoxia-inducible factor alpha, HIF-1α）与白细胞介素-4（Interleukin, IL-4）水平显著升高。本研究首次揭示了云南省ITP的流行病学特征，并强调了海拔对ITP患者细胞因子表达差异的影响。上述研究结果可为ITP的个性化治疗策略制定以及公共卫生政策的出台提供极具价值的参考依据。