Influence of body composition on 5 year mortality in patients on regular haemodialysis

Akihiko Kato1,5,, Mari Odamaki1,4, Tatsuo Yamamoto1, Katsuhiko Yonemura2, Yukitaka Maruyama3, Hiromichi Kumagai4 and Akira Hishida1

1 First Department of Medicine and 2 Dialysis Unit, Hamamatsu University School of Medicine, 3 Maruyama Hospital, 4 Department of Clinical Nutrition, School of Food and Nutritional Science, University of Shizuoka and 5 Shizuoka Cancer Center Hospital, Nagaizumi, Shizuoka, Japan



   Abstract
 Top
 Abstract
 Introduction
 Subjects and methods
 Results
 Discussion
 References
 
Background. Reduction of body mass index (BMI) significantly affects mortality in haemodialysis (HD) patients, but it remains to be determined which of the body components influences mortality.

Methods. We examined the whole body composition of 262 HD patients by dual-energy X-ray absorptiometry (DEXA) (age: 60±12 years; HD duration 9±7 years; male/female: 177/85; diabetics, n=50) and subsequently followed mortality for 5 years.

Results. Patient age was significantly correlated with limb/trunk lean mass (LTLM) ratio (r=-0.350, P<0.01) and % fat content in whole tissue (r=0.145, P=0.02). There was a significant positive relationship between LTLM ratio and serum creatinine both in males (r=0.404, P<0.01) and females (r=0.267, P=0.01). Diabetic males and females both had a significantly lower LTLM ratio than non-diabetic males (P<0.01) and females (P<0.04). During the 5 years, 65 patients (24.8%) died mainly of cardiovascular diseases and infections. BMI was lower in the expired group than in survivors (P<0.04). LTLM ratio was significantly reduced in the expired group compared with the surviving males (0.629±0.097 vs 0.707±0.094; P<0.01) and females (0.611±0.101 vs 0.651±0.078; P<0.01). Cox's proportional hazards analysis revealed that the reduction of LTLM ratio was a significant determinant of death in men (P<0.01), while a lower percentage of fat content of trunk was a significant determinant of death in women (P<0.01). In contrast, BMI did not influence mortality in either sex.

Conclusions. Measurements of regional lean and fat mass volumes by DEXA may be useful for predicting death in patients receiving long-term HD.

Keywords: DEXA; fat; haemodialysis; lean body mass; mortality



   Introduction
 Top
 Abstract
 Introduction
 Subjects and methods
 Results
 Discussion
 References
 
Protein-energy malnutrition is one of the most potent predictors of mortality in haemodialysis (HD) patients. Recently, body mass index (BMI), calculated as an individual's weight in kilograms divided by the square of his height in metres (kg/m2), has been shown to be correlated with mortality in HD patients [16]. Leavey et al. [1] first demonstrated that BMIs <24.4 kg/m2 predicted a significantly higher mortality during a 5 year observation in 3607 HD patients. Fleischmann et al. [2] also found that HD patients with BMIs <20.0 kg/m2 had a 1.6-fold increase in the relative risk of dying in 12 months of follow-up compared with those whose BMI ranged from 20 to 27.5 kg/m2. They found that underweight patients were admitted more frequently with pulmonary and vascular access-related problems. In addition, a simple calculation of weight-for-height ratio (kg/m) has been shown to be a strong predictor of 12 month mortality both in male and female HD patients [3]. However, BMI does not measure body fat volume directly and does not assess local distribution of lean and fat mass precisely.

Dual-energy X-ray absorptiometry (DEXA) is a useful tool to estimate regional body composition, directly providing measures of bone mineral and fat at the same time. DEXA can sensitively measure fat and lean soft tissue masses in patients with chronic renal failure [711]. Serial measurements of body fat mass by DEXA are useful for estimating short-term alterations of nutritional status in HD patients [12,13]. DEXA also can detect small changes of body fat and lean mass volumes in chronic renal failure patients on very low protein diets [11]. However, there has been no study to examine the impact of regional fat and lean mass distributions on mortality in dialysis patients.

The aim of this study was to evaluate the clinical relevance of body compositional analysis in patients receiving regular HD. After the measurement of initial lean and fat masses located trunk and extremities by DEXA, we followed our subjects for 5 years and examined factors of body composition which could influence their mortality.



   Subjects and methods
 Top
 Abstract
 Introduction
 Subjects and methods
 Results
 Discussion
 References
 
Study population
We selected 262 stable patients out of 310 at a single dialysis unit (Maruyama Hospital) in November 1996. We excluded from the study those patients who had acute infections, malignancy or liver cirrhosis. All patients were without pleural effusion and ascites at their initial assessment. The subjects comprised 177 men and 85 women with a mean age of 60±12 (30–90) years. Their mean time on HD was 9±7 years, ranging from 1 to 27 years. The causes of their end-stage renal failures were primary renal disease in 197 (75%), diabetes in 55 (21%) and autosomal dominant polycystic kidney disease in 10 (4%) patients. Residual urine output was below 400 ml/day in all patients. BMI was calculated as an individual's dry weight in kilograms divided by the square of his or her height in metres (kg/m2).

Haemodialysis-related factors
All patients had been undergoing regular HD via their arteriovenous fistulas 4–5 h three times per week at a blood flow rate of 180–220 ml/min. All patients used bicarbonate dialysate (30 mEq/l; Kindaly AF-2P, Fuso, Osaka, Japan) at a dialysis flow rate of 500 ml/min. HD treatments were performed using one of the following membranes: low-flux ultrafiltration rate (UFR<20 ml/mmHg·h) modified regenerated cellulose hollow-fibre (AM-SD, Asahi Medical, Tokyo, Japan; CL-EE, Terumo, Tokyo, Japan); medium-flux (UFR 20–40 ml/mmHg·h) cellulose triacetate hollow-fibre (FB-U, Nipro Medical, Osaka, Japan; TFW, Teijin-Gambro, Tokyo, Japan); high-flux (UFR>40 ml/mmHg·h) polysulphone synthetic hollow-fibre (BS-U, Toray Medical, Tokyo, Japan; APA, Asahi Medical, Tokyo, Japan). All patients had been using the same dialyser membrane for at least 1 year. There was no patient in our group who re-used the dialyser membrane. Blood samples were drawn from the arterial side of the arteriovenous fistula at the start and at the end of dialysis sessions after a 2 day interval in November 1996. The efficiency of the dialysis was assessed based on the delivered dose of dialysis (Kt/Vurea) using a single-pool urea kinetic model. Protein catabolic rate (PCR), an indirect indicator of protein intake, was calculated from dialysate and serum urea levels. Serum urea nitrogen, creatinine, total protein, albumin, total cholesterol, triglyceride, electrolytes and haemoglobin were measured by standard laboratory techniques using automatic analysers. Intact parathyroid hormone (PTH) was determined using immunoradiometric assay. Serum ferritin was determined by latex agglutination method.

Measurement of body composition by DEXA
DEXA was performed using a Lunar-DPX-L scanner (Lunar Corporation, Madison, WI, USA). The ratio of the mass attenuation coefficients of the two photon energies varies in a linear manner with the proportions of lean and fat masses in soft tissue, and the weights of fat and lean tissues are calculated from algebraic equations using the known attenuation ratios for fat and lean tissues. We assessed body composition in the supine position before meals, since the position of the patient and food intake can easily influence the measurement of whole body composition [14]. Because of time limitations, 190 (73%) patients had DEXA measurements before the start of HD and the others after the end of HD sessions. We used limb/trunk lean mass (LTLM) ratio as a marker of regional distribution of lean mass volume, since fat-free mass was similarly reduced in all body parts during a single HD [7,10,11]. We also used % tissue fat and whole body mineral density (BMD), because these parameters are not influenced by the removal of body fluid during a HD procedure [711].

Computer analysis of whole body scans was performed with V5.54 software using the extended research analysis mode. All patients were examined by the same observer. Regional analysis was conducted by manual division of the whole-body image into three subgroups: arms, legs and trunk. The division between arms and the trunk was done by drawing lines passing through the gleno-humeral joints and between the trunk and legs by a line passing obliquely through the hip joints at about 45° to the sagittal plane. The head was demarcated from the trunk by a transverse line passing below the mandible. The trunk thus consisted of the thorax, abdomen, pelvis and a portion of the upper medial thigh. The results were reported in grams of bone mineral content, fat, lean mass and lean tissue. The coefficients of variation for DEXA measurements by this method are reported to be <1%. Percentage of age-matched BMD was also calculated from standard Japanese BMD values.

Five year follow-up study
After the determination of initial laboratory and DEXA parameters, we followed all patients for 5 years until November 2001. We then divided all subjects into surviving and expired groups and evaluated the influence of clinical and DEXA parameters on mortality.

Statistical analysis
Values are expressed as means±SD. Differences between the two groups were analysed by an unpaired Student's t-test following the ANOVA method. P-values of <0.05 were considered statistically significant. Kaplan–Meier estimates of LTLM ratios and % fat tissue of trunk were calculated for the time of death during follow-up. The P-values for comparison of survival curves were determined by the log-rank test. The relative risk of different parameters was estimated using the Cox's proportional hazards model. Relative risks and their 95% confidence intervals (CI) were calculated using the estimated regression coefficients and their standard error in Cox's regression analysis. We evaluated 15 parameters: age, time on HD, diabetes, BMI, LTLM ratio, % total body fat content, % fat content of trunk, serum creatinine, urea nitrogen, albumin, phosphorous, total cholesterol, Kt/Vurea, intact PTH and PCR as a univariate model in each sex. In addition, chi-square statistics were obtained. All statistical calculations were performed with the StatView 5J software (SAS Institute Inc., Cary, NC, USA).



   Results
 Top
 Abstract
 Introduction
 Subjects and methods
 Results
 Discussion
 References
 
Patient characteristics and DEXA parameters
The LTLM ratio by DEXA analysis was significantly and inversely correlated with patient age (r=-0.350, P<0.01). In contrast, a significant and positive relationship was found between age and % fat content of total body (r=0.145, P=0.02), arms (r=0.239, P<0.01) and legs (r=0.188, P=0.02), but not the trunk. HD duration did not correlate with LTLM ratios and % fat contents of any region. The LTLM ratio was significantly higher in male patients (0.692±0.099, n=177) compared with female patients (0.637±0.089, n=85) (P<0.01). In contrast, total body % fat content was significantly lower in men than women (19.4±7.2% vs 27.8±8.8%; P<0.01). Male patients had a significantly lower % fat content in the trunk, arms and legs (P<0.01; data not shown). Diabetic subjects (n=55) had a significantly lower LTLM ratio compared with non-diabetics (n=207) both in males (0.654±0.090 vs 0.703±0.099; P<0.01) and females (0.607±0.067 vs 0.644±0.092; P<0.04). There was no significant difference in % fat content of total body, legs and the trunk between diabetic and non-diabetic patients.

The LTLM ratio was significantly and positively correlated with serum creatinine levels both in men (r=0.404, P<0.01) and women (n=0.267, P=0.01) (Figure 1Go). The LTLM ratio was also positively and significantly related to serum albumin in male patients (r=0.265, P<0.01) but not in female patients (Figure 2Go). These relationships, however, were not strong. In addition, the LTLM ratio did not correlate with other nutritional parameters, such as serum phosphate, total cholesterol, triglyceride, transferrin and PCR values, in each sex.



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Fig. 1.  Relationship between serum creatinine and LTLM ratio in men and women. There was a significant linear association between serum creatinine and LTLM ratio both in males (r=0.404, P<0.01) and females (r=0.267, P=0.01).

 


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Fig. 2.  Serum albumin and LTLM ratio in men and women. Serum albumin was significantly and positively correlated with LTLM ratios in men (r=0.265, P<0.01) but not in women.

 
The LTLM ratio was significantly and negatively correlated with % fat content of arms (r=-0.202, P<0.01) and legs (r=-0.238, P<0.01) in male patients. Limb/trunk fat mass ratio, an index of body fat distribution, was significantly and inversely correlated with blood total cholesterol (male: r=-0.233, P<0.01; female: r=-0.307, P<0.01) and triglyceride values (male: r=-0.336, P<0.01; female: r=-0.491, P<0.01).

Body composition and the 5 year mortality
Sixty-five HD patients (24.8%) died during the 5 year follow-up (male/female=35/30). The expired group had a significantly higher mean age at enrolment in the study (P<0.01; Table 1Go). There was no difference in time on HD between the two groups. The number of females and diabetics was significantly higher in the expired group (P<0.01). There was a slight but significant decrease in initial BMI in expired subjects (P<0.04). Basal serum creatinine level also was significantly lower in the expired group compared with the surviving group (P<0.01). Serum albumin was significantly lower in the expired patients (P<0.01). There was no difference in initial blood urea nitrogen, phosphate, haemoglobin, total cholesterol, triglyceride, intact PTH, ferritin and PCR values between the two groups (Table 1Go).


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Table 1.  Initial clinical parameters both in surviving and expired HD patients

 
The DEXA analysis indicated that there was a significant reduction of LTLM ratio in the expired group compared with the surviving group (Table 1Go). This difference was present both in men (0.630±0.095 vs 0.707±0.094; P<0.01) and women (0.611±0.101 vs 0.651±0.078; P<0.05). As expected, expired patients had significantly increased % fat volumes both of arms and legs (Table 1Go), possibly reflecting a relative reduction of fat-free mass in upper and lower limbs. In contrast, BMD did not differ between the two groups.

Impact of LTLM ratio on 5 year survival
Since the basal LTLM ratio was significantly different between men and women, we separately assessed the influence of body composition in each sex. We divided all patients into two groups according to their average values of LTLM (male: 0.7; female: 0.6) and evaluated the impact of the LTLM ratio.

In males, age was significantly higher in the patients with LTLM ratios lower than 0.7 (0.775±0.051, n=83) compared with those with ratios higher than 0.7 (0.619±0.069, n=94) (P<0.01; Table 2Go). Significant decreases in serum creatinine, albumin and BMI values were also found in HD patients with lower LTLM ratios (P<0.01). The prevalence of diabetes also was higher among patients with LTLM ratios less than 0.7 (P<0.01). There was a significant reduction of non-fat mass weight in arms (P<0.01) and legs (P<0.01) but not in the trunk in patients with lower LTLM ratios (Table 2Go).


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Table 2.  LTLM ratio and clinical and anthropometrical parameters in male dialysis patients

 
Kaplan–Meier analysis revealed that the survival rate during 5 years was significantly higher in male patients with LTLM ratios more than the average than those with ratios lower than the average (90.4 vs 72.3%, P<0.01; Figure 3Go). Twenty-seven of 94 male patients (28.7%) who had reduced LTLM ratios died during follow-up. The causes of death were acute myocardial infarction (n=9), pneumonia (n=8), chronic heart failure (n=7) and others (n=3). In contrast, eight of 83 male patients (9.6%) with preserved LTLM ratio died of cerebrovascular diseases (n=3), acute myocardial infarction (n=3) and other causes (n=2). A significantly higher prevalence was found of cardiovascular (63 vs 25%; P<0.01) and pulmonary deaths (30 vs 0%; P<0.01) in men with lower LTLM ratios.



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Fig. 3.  LTLM ratio and 5 year survival rate in men and women. Men with LTLM ratios <0.7 had a significantly lower survival rate during 5 years compared with those with ratios >0.7. Similarly, the women with lower LTLM ratios (<0.6) had a significantly lower survival rate at the end of the study. *P<0.05 and **P<0.01, compared with the two divided groups.

 
In female HD patients, there was no difference in age between those with LTLM ratios more than 0.6 (0.693±0.064, n=50) compared with those with ratios less than 0.6 (0.557±0.048, n=35) (Table 3Go). A significantly higher prevalence of diabetes was found in patients with lower LTLM ratios (P<0.01; Table 3Go). Serum creatinine was significantly lower in patients with reduced LTLM ratios (P<0.01). Lean mass volume at extremities, but not the trunk, was also significantly lower in patients with lower LTLM ratios (Table 3Go). In contrast, there was no difference in BMI and albumin values between the two groups.


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Table 3.  LTLM ratio and clinical and anthropometrical parameters in female dialysis patients

 
Kaplan–Meier analysis revealed that the survival rate during follow-up was significantly higher in female patients with LTLM ratios above 0.6 (n=50) than in those with ratios lower than 0.6 (n=35) (74.0 vs 51.4%, P<0.05; Figure 3Go). The causes of death in 27 (90.0%) of 30 female patients were vascular diseases, such as chronic heart failure, acute myocardial infarction and cerebral bleeding. In addition, female patients with % fat content of the trunk more than 25% (33.0±5.4%, n=50) had a significantly higher survival rate compared with those with % fat content <25% (16.5±5.6%, n=35) (45.2% vs 13.2%, P<0.01; Figure 4Go).



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Fig. 4.  Effect of % trunk fat content on 5 year survival in women. A significantly higher survival rate during 5 years was found in female patients with % fat content of trunk >25% than in those with % fat content <25%. **P<0.01, compared with patients with % trunk fat content >25%.

 
The impact of a reduced LTLM ratio was also confirmed when comparing the relative risk of mortality in each sex. Male patients with LTLM ratios less than 0.7 had a 3.3-fold higher risk of death compared with those with ratios above 0.7 (Table 4Go). Similarly, female patients with ratios less than 0.6 had a 2.2-fold higher risk of death (Table 4Go). Lower % fat content of trunk also indicated a 2.8-fold higher risk of death in women but not in men (Table 4Go).


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Table 4.  Relative risk of mortality according to lower and higher LTLM ratio and % fat content of trunk

 

Analysis of mortality rates
Cox's proportional hazards analysis was done to examine the independent factors for 5 year survival in each sex. Using univariate Cox's regression analysis, various factors, such as age, presence of diabetes, LTLM ratio, creatinine and albumin, were associated with mortality in each gender. In addition, % fat content in total body and trunk and total cholesterol were related to death in women (Table 5Go). The multivariate regression analysis demonstrated that the presence of diabetes and LTLM ratios were independent predictors of mortality in male patients. In female patients, age, diabetes and % fat content of the trunk were significant determinants of death (Table 5Go).


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Table 5.  Univariate and multivariate Cox's proportional hazards analysis for mortality during a 5 year follow-up of the subjects

 



   Discussion
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 Abstract
 Introduction
 Subjects and methods
 Results
 Discussion
 References
 
Recently, DEXA has been validated as a useful tool for assessing nutritional status in patients with chronic renal insufficiency [711]. Those studies have revealed that dialysis patients had a significantly lower whole lean mass volume compared with age-matched individuals in the general population [8,10], although that has not been a universal finding [15]. Woodrow et al. [7] first found that regional analysis with DEXA showed a significant reduction in limb lean tissue but not fat tissue in dialysis patients when compared with healthy subjects. They demonstrated that the ratio of limb/trunk lean tissue was lower in women than men in non-diabetic patients on HD. Also, DEXA can detect serial changes of fat-free mass and fat mass [11]. However, the number of patients studied for those papers was small and the clinical significance of those compositional parameters remains undefined.

In this study, we confirmed a significant reduction of LTLM ratio in female compared with male HD patients, as described previously [7]. In addition, older and diabetic patients had a significantly lower LTLM ratio, but a significantly higher total body % fat content. The LTLM ratio was positively correlated with serum creatinine, indicating a close relationship between whole muscle volume and this ratio. In general, the major site of protein loss is muscle and visceral organ proteins are relatively spared in cases of protein depletion [16]. So, our finding indicated that a lower LTLM ratio was probably due to a decrease in muscle volume primarily in upper and lower limbs.

Many studies have been conducted to examine a putative relationship between mortality and anthropometrical parameters in HD patients, but it still remains uncertain which compositional markers of the body might be useful in predicting mortality and morbidity in dialysis patients. Maggiore et al. [17] demonstrated by bioelectrical impedance analysis (BIA) that the reduction of whole cell volume mass but not of mid-arm muscle circumference was a significant determinant of 2 year survival in HD patients. In contrast, a recent large-cohort study [18] showed that BMI or lower ratios of observed/expected lean body mass did not influence the 2 year survival in HD patients. They also found that observed/expected lean body mass ratio did not contribute to the 2.5 year survival in patients older than 75 years [19]. In this study, we first found that a relative decrease in the LTLM ratio indicated a significantly lower survival in HD patients. The relative risk of mortality with LTLM ratios less than 0.7 in men and less than 0.6 in women was 3.3 and 2.2 times higher, respectively. The multivariate Cox's proportional hazards analysis revealed that reduced LTLM ratios were significant determinants of 5 year mortality in men. In women, % fat content of the trunk was a significant determinant of mortality. The female patients with % fat of the trunk <25% had a 2.8-fold higher risk of death compared with those with >25% fat. In contrast, BMI did not affect mortality in either sex. These findings convincingly suggested that DEXA parameters could be superior predictors of death in dialysis patients when compared with BMI. In this study, however, the relationships between the LTLM ratio and other nutritional markers were weak. The reason for this poor association remains unknown, but may be due to the relatively well-preserved blood albumin levels in our patients. The prevalence of serum albumin <3.5 g/dl was only 11.1%, which was much less than the usual estimate of 20–30% [20].

In our study, we also found that lower % fat content in the trunk was a significant predictor of death in women (Table 4Go), a finding contrary to that observed in the general female population [21]. The reasons for this discrepancy between female HD patients and healthy women remain unknown, but may include, in part, differences in blood lipid profiles. In our patients, elevated serum triglyceride (>180 mg/dl) was found only in 25.9% and total cholesterol (>220 mg/dl) only in 10.6%. An increased tissue % fat in the trunk may rather reflect a well-nourished status, which may eventually lead to a better outcome in female patients. Recent cohort studies have also demonstrated that mortality was lower in HD patients who weighed more than normal [24], indicating that obesity does not seem to exert a negative impact on survival in dialysis patients. In contrast, trunk fat mass did not correlate with survival in men. Since % fat content was clearly lower in our male patients (19.2±0.6% vs 26.2±1.1%; P<0.01), despite their younger age (57±1 vs 64±1; P<0.01), the impact of the fat mass volume of the trunk on mortality may be less in male dialysis patients.

The mechanisms whereby a greater depletion of lean tissue in the extremities is associated with higher mortality remain undetermined by this study. Pro-inflammatory cytokine is suggested as a possible candidate for the uraemia-induced acceleration of muscle protein degradation via proteolytic pathways [22]. In rats, continuous administration of tumour necrosis factor (TNF) caused skeletal muscle catabolism, resulting in loss of lean body mass [23]. An increase in basal energy expenditure is also associated with a reduced lean but not fat mass volume in patients with chronic renal insufficiency [24]. Since blood TNF-{alpha} and interleukin-6 are greatly elevated and associated with mortality in HD patients [25], lasting inflammation may cause wasting of extremities and ultimately fatal malnutrition in these patients. Recently, Johansen et al. [26] demonstrated that poor physical performance in outpatients on HD is related to advanced age and comorbid illnesses, including diabetes. In addition, they found that poor physical activity is associated with decreased muscle masses as estimated by BIA. In this study, the expired patients were older and had a higher prevalence of diabetes. Therefore, a greater reduction of lean mass at extremities may simply be due to poor physical function in the expired group, which contained more elderly and diabetic persons.

The major limitation of this study is the timing of DEXA relative to the HD sessions. We conducted DEXA analysis in 190 patients before dialysis (male/female=146/44) and in 72 patients after dialysis (male/female=31/41). Hydration can impact lean mass as values derived from DEXA presume constant water content per unit of tissue [10]. Since the so-called lean mass includes heterogeneous tissues such as lung, heart and intestine in the trunk and mainly muscles in the limbs, fluid removal would be expected to differently affect the lean masses of the trunk and the limbs. A previous study showed, however, that a single HD session equally reduces lean mass volume both of the trunk and arms (-6.6 vs -6.4%) [10]. A similar reduction of lean mass was also observed in trunk and legs in a small study [27]. We preliminarily confirmed that actual lean mass volume in male patients obtained before dialysis (n=146) was associated with mortality by a univariate model ({chi}2=6.14, relative risk=0.92; P=0.01); in this study, we used the LTLM ratio instead of actual lean mass volume. On the other hand, total body fat masses measured before or after dialysis were identical both in men (10.3±5.0 vs 10.0±4.0 kg; P=NS) and women (12.8±7.5 vs 11.7±5.1 kg; P=NS). Absolute regional fat mass was also comparable between the two groups that had different timing of DEXA measurements, indicating a minor influence of fluid removal on regional fat analysis by DEXA, as described previously [7,10,11]. Since we could not fully exclude the influence of the timing of measurements on body composition analysis, additional larger studies are needed to further clarify the clinical relevance of DEXA parameters in predicting death.

In summary, we found that the LTLM ratio was reduced in older and diabetic HD patients. Lower LTLM ratio turned out to be a significant determinant of 5 year mortality in male patients. In female patients, % fat mass content lower than 25% turned out to be a significant predictor of death. In contrast, BMI did not influence mortality in men or women. These findings strongly suggest that measurements of regional lean and fat mass distributions by DEXA could be better predictors for all mortality in patients on maintenance HD.



   Acknowledgments
 
We thank the laboratory and radiological staff of Maruyama Hospital (Hamamatsu, Japan) for DEXA measurements and other laboratory data.



   Notes
 
Correspondence and offprint requests to: Akihiko Kato, MD, Division of Nephrology, Endocrinology and Metabolism, Shizuoka Cancer Center Hospital, 1007 Shimonagalubo, Nagaizumi, Sunto-gun, Shizuoka 411-8777, Japan. Email: a.kato{at}scchr.jp Back



   References
 Top
 Abstract
 Introduction
 Subjects and methods
 Results
 Discussion
 References
 

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Received for publication: 30. 4.02
Accepted in revised form: 30. 8.02