Abstract: 【Abstract】Objective We first established a formula for calculating overhydration (OH) in healthy population in the local region, and then used this formula to titrate the target dry body weight and to observe the 24-hour ambulatory blood pressure monitoring (ABPM) changes and the incidence of adverse events in maintenance hemodialysis (MHD) patients. Methods The first stage of the study was an observational study, which enrolled 314 healthy people after physical examinations at Baotou Central Hospital. Body composition monitor (BCM) was used to measure their volume load status and body composition. The OH-related multiple regression formula was obtained by multivariate linear regression analysis. The second stage was an intervention study, which enrolled MHD patients with OH and mean 24-hour ABPM ≥130/80 mmHg. The OH-related regression formula was applied to titrate the target dry weight. Results The multivariate linear regression formula for OH in healthy people is OH=6.203-0.019× Y-0.083×G-0.006×F+0.098×L-1.437×P (F=189.896, R2=0.755, P＜0.001; Y: age; G: sex; F: lipid ass; L: lean tissue mass; P: phase angle). Eight MHD patients were enrolled in the study. After adjustment, 75% of the patients had a dry weight compliant with the target value. The 24-hour ABPM showed that the proportion of systolic blood pressure≥180mmHg decreased from
30.188 ± 15.957% to 4.088 ± 2.719% (t=4.831, P=0.002), and the proportion of systolic blood pressure ≤ 159mmHg increased from 28.713±24.672% to 71.688±16.545% (t=-6.207, P= 0.001). Conclusion The OHrelated calculation formula obtained from healthy population can be used for dry body weight management individually in MHD patients.

Key words: Dry weight, Overhydration, Body composition, 24-hour ambulatory blood pressure