The Role of Lean Body Mass as a Nutritional Index in Chinese Peritoneal Dialysis Patients—Comparison of Creatinine Kinetics Method and Anthropometric Method

Abstract

Objective To compare, in Chinese continuous ambulatory peritoneal dialysis (CAPD) patients, the creatinine kinetics method (LBM-CK) and the anthropometric method (LBM-AM) for determining lean body mass (LBM). Design Single-center cross-sectional study. Patients and Methods We studied 151 unselected CAPD patients (78 males, 73 females). We calculated LBM-CK and LBM-AM using standard formulas. The results of the two methods were then compared by the Bland and Altman method. Dialysis adequacy and other nutritional indices, including total Kt/V, weekly creatinine clearance (CCr), residual glomerular filtration rate (GFR), protein nitrogen appearance (PNA), subjective global assessment (SGA), and serum albumin, were measured simultaneously. Results The mean age of the patients was 55.6 ± 12.2 years, and the mean duration of dialysis was 33.6 ± 28.5 months. The mean body mass index (BMI) was 22.7 ± 3.7. The average LBM-AM was 43.6 ± 8.0 kg; the average LBM-CK was 33.0 ± 9.3 kg. The difference between the calculated LBM-AM and LBM-CK was 10.7 kg, with LBM-AM always giving a higher value; the limits of agreement were –5.8 kg and 27.1 kg. The difference between the two measures correlated with residual GFR (Pearson r = 0.629, p < 0.001). After normalizing for desired body weight, LBM-AM was only modestly correlated with serum albumin level. No correlations were found between overall SGA score or normalized protein nitrogen appearance (nPNA) and LBM-AM or LBM-CK. Conclusions In Chinese patients at least, a substantial discrepancy exists between LBM-AM and LBM-CK. The difference is especially marked in patients with significant residual renal function. The optimal method for determining LBM remains obscure in Chinese CAPD patients. Moreover, LBM correlated poorly with other nutritional indices. Multiple parameters should be taken into consideration in an assessment of nutritional status of CAPD patients.

The Impact of Increasing the Daytime Dialysis Exchange Frequency on Peritoneal Dialysis Adequacy and Nutritional Status of Chinese Anuric Patients

“…Total body water (V) was determined using Watson et al ‘s formula (15). Percentage lean body mass (%LBM) was determined using the creatinine kinetics method, according to Forbes and Bruining (16), that was described in detail in our previous study (17). Serum albumin concentration, %LBM, and nPNA were used as nutritional parameters in this study.…”

Influence of megestrol acetate on nutrition, inflammation and quality of life in dialysis patients

“…A significant increase in albumin concentration can occur together with muscle mass depletion. Lean body mass, as determined by creatinine kinetics [ 38 ], anthropometry and bioelectrical impedance, correlated poorly or not at all with serum albumin level [ 39 ]. Megestrol acetate has glucocorticoid-like activity [ 25 , 40 ], and glucocorticoids are known to upregulate albumin gene expression in vitro [ 41 ] and to increase albumin synthesis in vivo [ 42 ], while stimulating muscle protein breakdown.…”

Assessment of Protein Nitrogen Appearance in Chinese Peritoneal Dialysis Patients—Which Method to Use?

“…Our previous study found that lean body mass determined by anthropometric method had poor correlation with that derived from creatinine kinetics and may not be reliable in Chinese. [25] The Bergstrom's formula is now regarded as the ideal method for calculation of PNA. [3,4] Although the DOQI guidelines also recommend the Randerson's formula, [4,5] there are methodological concerns.…”