[Use of dual energy X-ray absorptiometry (DEXA) in the determination of total body water in patients undergoing chronic dialysis].
In order to assess Total Body Water (TBW), three methods are compared, in 18 patients on regular dialysis treatment: DEXA, Bioimpedance Analysis (BIA) and urea Kinetic Volume (V urea). The mean difference between gravimetric weight and Total Body Mass (TBM) DEXA is closed (1.04 kg, SD of differences 0.4 kg). The mean difference between delta pre-post HD gravimetric weight loss (2.6 kg) and delta pre-post TBM DEXA is--0.03 kg (SD 0.28). TBW measured with the three methods are (Liters): TBW DEXA = 31.2 (SD 5.2), TBW BIA = 29.7 (SD 5.2), TBW V urea = 29.1 (SD 4.8). TBW comparisons between the three methods are (Liters): TBW DEXA-TBW BIA = mean 1.5 (SD 3.8), r = 0.73. TBW DEXA-TBW V urea = mean 2.1 (SD 2.2), r = 0.88. TBW BIA-TBW V urea = mean 0.6 (SD 3.6), r = 0.80. Hydration index of lean body mass, calculated by assuming V urea as standard, is 0.69 (SD 0.05), range 0.62-0.77, in agreement with others studies. In conclusion DEXA, a useful method for body composition and nutritional status assessing, represents a new tool for measuring hydration status, combined with others TBW evaluation formulas (BIA or V urea).
Nebiolo
P E
PE
Servizio di Nefrologia e Dialisi, Ospedale Regionale Valle d'Aosta, Aosta.
Manes
M
M
Bonfant
G
G
Varetto
T
T
Cantalupi
D
D
Alloatti
S
S
D015502:Absorptiometry, Photon; D001834:Body Water; D005260:Female; D006801:Humans; D008297:Male; D012044:Regression Analysis; D006435:Renal Dialysis