Low BMI and high waist-to-hip ratio are associated with mortality risk among hemodialysis patients: a multicenter prospective cohort study

作者：Yang, Yaya; Zhang, Haixia; Lan, Xiaolei; Qin, Xianhui; Huang, Yan; Wang, Jieyu; Luo, Pei; Wen, Zhen; Li, Yumin; Kong, Yaozhong; Wan, Qijun; Wang, Qi; Huang, Sheng; Liu, Yan; Liu, Aiqun; Liu, Fanna; Yang, Shenglin; Lu, Yongxin; Zhao, Yanhong; Chen, Junzhi; Lei, Zihan; He, Yanhuan; Lin, Zizhen; Li, Youbao; Liang, Min

来源：Clinical Kidney Journal, 2023, 16(1): 167-175.

DOI：10.1093/ckj/sfac210

• all-cause mortality
• body mass index
• cardiovascular mortality
• hemodialysis
• waist-to-hip ratio

Background Data are limited on the relationship between waist-to-hip ratio (WHR) and mortality risk among maintenance hemodialysis (MHD) patients. Moreover, the combined association of body mass index (BMI) and WHR with mortality remains uncertain. Therefore, we aimed to explore the individual and combined association of BMI and WHR with the all-cause and cardiovascular disease (CVD) mortality. Methods In this multicenter prospective cohort study, we enrolled 1034 MHD patients. The primary outcome was all-cause mortality and secondary outcome was CVD mortality. Multivariable Cox proportional hazards models were used to evaluate the individual and combined association of BMI and WHR with the risk of mortality. Results A nonlinear inverse relationship was found between BMI and risk of all-cause mortality (P for nonlinearity <.05). Being underweight (<18.5 kg/m(2)) was associated with higher all-cause mortality risk (HR 1.45; 95% CI 1.08-1.94) compared with normal weight (18.5-23.9 kg/m(2)), while being overweight (24-27.9 kg/m(2); HR 0.96; 95% CI 0.70-1.31) and obese (>= 28 kg/m(2); HR 1.19; 95% CI 0.62-2.26) showed no significant differences. Of note, WHR was independently and positively associated with all-cause mortality (per standard deviation increase, HR 1.13; 95% CI 1.00-1.27). When analyzed jointly, patients with low BMI (<18.5 kg/m(2)) and high WHR (>= 0.95) had the highest risk of all-cause mortality. Similar results were obtained for CVD mortality. Conclusions In patients undergoing hemodialysis from China, low BMI and high WHR were individually and jointly associated with higher risk of mortality. Our results emphasize that BMI and WHR may jointly affect the prognosis of MHD patients. @@@ Lay Summary Several studies have reported that a high body mass index (BMI) is related to better survival in maintenance hemodialysis (MHD) patients. However, BMI fails to reflect the distribution of body fat, especially the abdominal fat, which can be measured by waist-to-hip ratio (WHR). The relationship of BMI and mortality risk may hide the detrimental effects of abdominal fat. As such, we aimed to explore the individual and combined relationship of BMI and WHR with mortality risk in MHD patients. We enrolled 1034 MHD patients in this multicenter prospective cohort study. During a median follow-up of 45.6 months, we found that low BMI (<18.5 kg/m(2)) and high WHR (>= 0.95) were individually and jointly associated with higher mortality risk in MHD patients. Our findings highlight that comprehensive consideration of BMI and WHR is of great significance to the assessment and improvement of the prognosis of patients undergoing MHD.

• 单位
  南方医科大学; 佛山市第一人民医院; 1; 深圳市第二人民医院