Body composition and cardiovascular risk factors in pretransplant hemodialysis patients

BACKGROUND: Obesity, hyperlipemia and cardiovascular complications contribute to a significant proportion of morbidity and mortality of renal transplant patients and have negative effects on renal survival. Aim of the present study was to evaluate the main abnormalities in body composition and the prevalence of some cardiovascular risk factors in a population of hemodialyzed (HD) patients awaiting renal transplantation. METHODS: We studied 151 HD patients, all included in a waiting list for renal transplantation, 97 males and 54 females, with mean age 47.4+/-12 years. Patients were divided into three groups according to their body mass index (BMI) (kg/m2): 18.5 to 24.9 (normoweight, NW); 25.0 to 29.9 (overweight, OW); > or =30 (obese, OB). The body composition measurements were obtained the day after the mid-week HD session using bioelectrical impedance analysis (BIA). RESULTS: We found that 47 patients were NW (31%), while 56 were OW (37%), and 48 were OB (32%). BIA-measured body cell mass was (BCM) significantly increased in the OW as compared with the NW group (P<0.001), but, of note, no significant difference was found in OB group in comparison with the OW. Total cholesterol and triglycerides plasma levels were significantly elevated in OW and OB patients with respect to NW (P<0.05) and an increased prevalence of diabetes was seen in OB patients (NW: 6%, OW: 5%, OB: 12%). CONCLUSIONS: These data show that a large proportion of patients awaiting renal transplant are overweight or obese and a consistent part of them have other cardiovascular risk factors associated. Furthermore, obese HD patients have a BCM lower than predicted on the basis of BMI and show an altered metabolic profile. A better understanding of the characteristics of patients included in the renal transplant waiting list is crucial in order to design prospective studies that aim to define the proper risk profile for the selection of patients

Impedance vector distribution by body mass index and conventional bioelectrical impedance analysis in obese women

BACKGROUND AND AIM: To compare the body fluid status assessments provided by conventional bioelectrical impedance analysis (BIA) and vector BIA in moderate and severe obesity. METHODS AND RESULTS: We studied 516 normotensive Caucasian women (mean age: 48 +/- 9.2 years), who were age-matched and divided into four groups on the basis of their body mass index (BMI): 99 normal weight women with a BMI of 19-25 Kg/m2; 228 preobese overweight women with a BMI of 25-30 Kg/m2; 132 women with class I-II obesity (BMI: 30-35 Kg/m2), and 57 women with class III obesity (BMI: 40-64 Kg/m2). Single-frequency (50 kHz) tetrapolar (hand-foot) bioelectrical impedance measurements were made, and total body water (TBW) and extracellular water (ECW) were estimated using conventional BIA regression equations. The RXc graph method was used for vector BIA, with the set of 327 women with a BMI of 19-30 Kg/m2 being adopted as the reference population. Mean vector displacement followed a definite pattern, with progressive vector shortening as the BMI increased, and along a fixed phase angle. This pattern indicates more TBW due to a greater soft tissue mass with average normal hydration. Short and downsloping vectors indicating fluid overload were more frequent in the group with class III obesity than in the group with class I obesity (19 vs 5%). The absolute values of TBW and ECW were significantly higher in the obese and overweight subjects than in those with normal weight subjects. TBW as a percentage of body weight was significantly lower in the obese subjects. CONCLUSIONS: BMI influenced the impedance vector distribution pattern, which proved to be consistent up to a BMI of 64 Kg/m2. Obese women with an altered body composition can be identified and monitored using vector BIA

Role of dietary intervention and nutritional follow-up in heart transplant recipients

BACKGROUND: Obesity, dyslipidemia, hypertension, and diabetes mellitus are common features after heart transplantation and they lead to coronary artery disease and graft loss. AIM: To determine the effects of a dietary intervention on nutritional status and metabolic outcome of two groups enrolled during or after the first year from the transplant. METHODS: Forty two subjects (mean age 51.36+/-12.4 yr) were studied; 20 were enrolled during the first year by the transplant, 22 were enrolled after the first year from the transplant (7.9+/-3.86 and 56.86+/-38.6 months after surgery, respectively). According to diet compliance both groups were divided into two subgroups and they were prospectively followed for 4 years. Anthropometric measurements, biochemical nutritional markers, and dietary records were collected at baseline (T0) and after a 12-month follow-up period (T12) and a 48-month follow-up period (T48). Body composition was performed at T0 and T12. RESULTS: Diet compliance was associated with a decrease in total cholesterol, triglycerides and glucose plasma level and with a weight loss mainly due to a decrease in fat mass. CONCLUSION: Our study shows the efficacy of dietary intervention to obtain an early and late weight and metabolic control after heart transplant