Cardiac Function Transition in Patients with Chronic Kidney Disease Undergoing Maintenance Hemodialysis in a High-Altitude Multi-Ethnic Region: A Comparative Study Between Yi and Non-Yi Ethnic Groups

Jingjing Zhang,1– 3,* Zhaoyu Li,4,* Xueliang Xiao,5 Xuesong Liu,6 Qian Qiao,1– 3 Lu Cheng,1– 3 Jun Sha,5 Yufei Yang,7 Wangzheqi Zhang,8 Haoling Zhang,9 Xuerui Ye1– 3 1Fuwai Yunnan Hospital, Chinese Academy of Medical Sciences, Affiliated Cardiovascular Hospital of Kunming Medical University, Kunming, 650000, People’s Republic of China; 2Yunnan Provincial Cardiovascular Clinical Medical Center, Kunming, 650000, People’s Republic of China; 3Yunnan Provincial Cardiovascular Clinical Medical Research Center, Kunming, 650000, People’s Republic of China; 4College of Acupuncture-Moxibustion and Tuina, Gansu University of Chinese Medicine, Lanzhou, 730000, People’s Republic of China; 5Internal Medicine Department II, Ninglang Yi Autonomous County People’s Hospital, Ninglang, 674300, People’s Republic of China; 6Basic Medical College, Gansu University of Chinese Medicine, Lanzhou, 730000, People’s Republic of China; 7School of Public Health, Gansu University of Chinese Medicine, Lanzhou, 730000, People’s Republic of China; 8School of Anesthesiology, Naval Medical University, Shanghai, People’s Republic of China; 9Department of Biomedical Sciences, Advanced Medical and Dental Institute, Universiti Sains Malaysia, Kepala Batas, Penang, 13200, Malaysia*These authors contributed equally to this workCorrespondence: Haoling Zhang, Email [email protected] Xuerui Ye, Email [email protected]: Cardiovascular disease is the leading cause of mortality in patients with chronic kidney disease (CKD), particularly among those undergoing maintenance hemodialysis (MHD). High-altitude exposure may further aggravate cardiovascular stress through chronic hypoxia. However, longitudinal data in multi-ethnic high-altitude dialysis populations remain limited.Objective: To evaluate changes in cardiac function in CKD stage 5/end-stage renal disease patients receiving MHD at high altitude and to compare findings between Yi and non-Yi ethnic groups.Methods: This retrospective study included 161 patients (103 Yi, 58 non-Yi) undergoing MHD in Ninglang Yi Autonomous County (mean altitude > 2800 m). Clinical characteristics, laboratory parameters—including homocysteine (HCY)—and echocardiographic indices were assessed at baseline, 3 months, and 12 months. Longitudinal trends and ethnic differences were analyzed.Results: In the overall cohort, pulmonary artery systolic pressure (PASP) increased significantly over time (P=0.049), while the E/A ratio declined, indicating progressive diastolic impairment. Left ventricular ejection fraction (LVEF) remained stable At 12 months, Yi patients had higher HCY levels (P=0.034), lower albumin (P=0.010) and apolipoprotein A levels (P=0.044), and a higher incidence of aortic regurgitation (AR) (P=0.012). Baseline E/A ratio was higher in Yi patients (P=0.032).Conclusion: CKD patients undergoing MHD at high altitude exhibit dynamic changes in cardiac function, predominantly involving pulmonary pressure and diastolic parameters. Ethnic differences in selected biochemical and echocardiographic indices suggest the need for tailored cardiovascular monitoring in high-altitude multi-ethnic dialysis populations.Keywords: chronic kidney disease, maintenance hemodialysis, high altitude, ethnic differences, cardiac function, pulmonary artery systolic pressure