Association of morbid obesity and weight change over time with cardiovascular survival in hemodialysis population.
ABSTRACT In maintenance hemodialysis (MHD) outpatients, a reverse epidemiology is described, ie, baseline obesity appears paradoxically associated with improved survival. However, the association between changes in weight over time and prospective mortality is not known.
Using time-dependent Cox models and adjusting for changes in laboratory values over time, the relation of quarterly-varying 3-month averaged body mass index (BMI) to all-cause and cardiovascular mortality was examined in a 2-year cohort of 54,535 MHD patients from virtually all DaVita dialysis clinics in the United States.
Patients, aged 61.7 +/- 15.5 (SD) years, included 54% men and 45% with diabetes. Time-dependent unadjusted and multivariate-adjusted models, based on quarterly-averaged BMI controlled for case-mix and available time-varying laboratory surrogates of nutritional status, were calculated in 11 categories of BMI. Obesity, including morbid obesity, was associated with better survival and reduced cardiovascular death, even after accounting for changes in BMI and laboratory values over time. Survival advantages of obesity were maintained for dichotomized BMI cutoff values of 25, 30, and 35 kg/m2 across almost all strata of age, race, sex, dialysis dose, protein intake, and serum albumin level. Examining the regression slope of change in weight over time, progressively worsening weight loss was associated with poor survival, whereas weight gain showed a tendency toward decreased cardiovascular death.
Weight gain and both baseline and time-varying obesity may be associated with reduced cardiovascular mortality in MHD patients independent of laboratory surrogates of nutritional status and their changes over time. Morbidly obese patients have the lowest mortality. Clinical trials need to verify these observational findings.
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ABSTRACT: Background Obesity and sedentary lifestyle are major health problems and key features to develop cardiovascular disease. Data on the effects of lifestyle interventions in diabetics with chronic kidney disease (CKD) have been conflicting. Study DesignSystematic review. PopulationDiabetes patients with CKD stage 3 to 5. Search Strategy and SourcesMedline, Embase and Central were searched to identify papers. InterventionEffect of a negative energy balance on hard outcomes in diabetics with CKD. OutcomesDeath, cardiovascular events, glycaemic control, kidney function, metabolic parameters and body composition. ResultsWe retained 11 studies. There are insufficient data to evaluate the effect on mortality to promote negative energy balance. None of the studies reported a difference in incidence of Major Adverse Cardiovascular Events. Reduction of energy intake does not alter creatinine clearance but significantly reduces proteinuria (mean difference from -0.66 to -1.77 g/24 h). Interventions with combined exercise and diet resulted in a slower decline of eGFR (-9.2 vs. -20.7 mL/min over two year observation; p<0.001). Aerobic and resistance exercise reduced HbA1c (-0.51 (-0.87 to -0.14); p = 0.007 and -0.38 (-0.72 to -0.22); p = 0.038, respectively). Exercise interventions improve the overall functional status and quality of life in this subgroup. Aerobic exercise reduces BMI (-0.74% (-1.29 to -0.18); p = 0.009) and body weight (-2.2 kg (-3.9 to -0.6); p = 0.008). Resistance exercise reduces trunk fat mass (-0,7±0,1 vs. +0,8 kg ±0,1 kg; p = 0,001-0,005). In none of the studies did the intervention cause an increase in adverse events. LimitationsAll studies used a different intervention type and mixed patient groups. Conclusions There is insufficient evidence to evaluate the effect of negative energy balance interventions on mortality in diabetic patients with advanced CKD. Overall, these interventions have beneficial effects on glycaemic control, BMI and body composition, functional status and quality of life, and no harmful effects were observed.PLoS ONE 11/2014; 9(11):e113667. · 3.53 Impact Factor
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ABSTRACT: To study the body mass index (BMI) trajectory in patients with incident end-stage kidney disease and its association with all-cause mortality. This longitudinal cohort study included 17022 adult patients commencing hemodialysis [HD] (n = 10860) or peritoneal dialysis [PD] (n = 6162) between 2001 and 2008 and had ≥6-month follow-up and ≥2 weight measurements, using the Australia and New Zealand Dialysis and Transplant Registry data. The association of time-varying BMI with all-cause mortality was explored using multivariate Cox regression models. The median follow-up was 2.3 years. There was a non-linear change in the mean BMI (kg/m2) over time, with an initial decrease from 27.6 (95% confidence interval [CI]: 27.5, 27.7) to 26.7 (95% CI: 26.6, 26.9) at 3-month, followed by increments to 27.1 (95% CI: 27, 27.2) at 1-year and 27.2 (95% CI: 26.8, 27.1) at 3-year, and a gradual decrease subsequently. The BMI trajectory was significantly lower in HD patients who died than those who survived, although this pattern was not observed in PD patients. Compared to the reference time-varying BMI category of 25.1-28 kg/m2, the mortality risks of both HD and PD patients were greater in all categories of time-varying BMI <25 kg/m2. The mortality risks were significantly lower in all categories of time-varying BMI >28.1 kg/m2 among HD patients, but only in the category 28.1-31 kg/m2 among PD patients. BMI changed over time in a non-linear fashion in incident dialysis patients. Time-varying measures of BMI were significantly associated with mortality risk in both HD and PD patients.PLoS ONE 12/2014; 9(12):e114897. · 3.53 Impact Factor
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ABSTRACT: Similar to the general population, cardiovascular disease is the leading cause of death in patients with a functioning renal graft. Recent studies have shown an inverse relationship between cardiovascular risk factors and outcomes in dialysis patients. Low blood pressure, low body mass index (BMI) and low serum cholesterol levels are correlated with a higher risk of adverse cardiovascular outcomes in dialysis patients. The explanation for these observations is unclear. In renal transplant recipients (RTR), these parameters are correlated with a lower risk of cardiovascular adverse outcomes, a phenomenon labeled as “reversal of reverse epidemiology.” The aims of this review are: (1) to explore the association between cardiovascular risk factors and outcomes in RTR; (2) to assess whether these effects are reversal of the reverse epidemiology in dialysis predecessors; and (3) to determine the strategies for minimizing cardiovascular risk in RTR. This article also compares the determinants of cardiovascular risk factors among the general population, maintenance dialysis patients and RTR. Because definitive evidence on optimal intervention is lacking, population-specific clinical trials are needed to define optimum targets for treatment of these risk factors in maintenance dialysis patients and RTR separately.Seminars in Dialysis 11/2007; 20(6). · 2.25 Impact Factor