Vintage, nutritional status, and survival in hemodialysis patients (original) (raw)

2000, Kidney International

6% increase in the risk of death, all else equal. Longitudinal Vintage, nutritional status, and survival in hemodialysis paassessments of nutritional status, including body composition, tients. are required to better understand the natural history of wasting Background. The link between dialysis "vintage" (length of with ESRD and its implications for long-term survival. time on dialysis in months to years) and survival has been difficult to define, largely because of selection effects. Endstage renal disease (ESRD) is thought to be a wasting illness, but there are no published reports describing the associations The link between dialysis "vintage" (length of time on between vintage and body composition in hemodialysis patients. dialysis in months to years) and survival of hemodialysis Methods. We explored the relationships among vintage, nupatients has been difficult to define, largely because of tritional status, and survival in a 3009 patient cohort of prevalent hemodialysis patients. Body weight, total body water, body selection effects. Over time, patients leave the dialysis cell mass, and phase angle by bioelectrical impedance analysis realm either because of transplantation or death, so that were the body composition parameters of interest. We examthe steady-state (that is, prevalent) dialysis population ined vintage as an explanatory variable in multiple linear rediffers considerably from the incident population. Acgression analyses (adjusted for age, gender, race, and diabetes) cordingly, patients of long vintage might be expected using body composition parameters and biochemical indicators of nutritional status as dependent variables. Proportional hazto differ greatly from patients of short vintage. Several ards regression was used to evaluate the association of vintage reports have described clinical characteristics of "longand survival with and without adjustment for case mix and term dialysis survivors." [1-3]. In general, long-term surlaboratory variables. vivors tend to be younger in age at the time of dialysis Results. Dialysis vintage was 3.8 Ϯ 3.7 (median 2.6) years. initiation and African American rather than white. Pri-Body composition parameters tended to be lower after dialysis year 2. Linear estimates per year of vintage beyond year 2 mary renal diseases are more likely to be glomeruloneinclude Ϫ0.66 kg body wt (P Ͻ 0.0001), Ϫ0.17 kg total body phritis or polycystic kidney disease rather than diabetes water (P ϭ 0.0003), Ϫ0.14 kg body cell mass (P Ͻ 0.0001), mellitus, hypertensive nephrosclerosis, or other condiand Ϫ0.07 degrees phase angle (P Ͻ 0.0001). In unadjusted tions. analyses, vintage was not associated with survival, either as a Few investigators have explored the association of vinlinear or higher order term. The adjustment for case mix yielded a vintage term associated with an increased relative tage with nutritional status in end-stage renal disease risk (RR) of death (RR 1.04 (95% CI, 1.01 to 1.07 per year). (ESRD). Avram et al compared long-term (Ͼ10 years) A further adjustment for laboratory data yielded a RR of 1.06 with "average" (Ͻ5 years) survivors on dialysis, and (95% CI, 1.03 to 1.09 per year). found that the serum albumin and creatinine concentra-Conclusion. Dialysis vintage is related to nutritional status tions at dialysis enrollment were higher in the 86 patients in hemodialysis patients, with vintage of more than years associated with a significant decline in all measured nutritional pa-(58 hemodialysis and 28 peritoneal dialysis) of extended rameters. Cross-sectional analyses probably underestimate vintage (Ͼ10 years) [3]. Lowrie and Lew found an inverse these effects. A year accrued on dialysis is associated with a relationship between vintage and death risk in prevalent hemodialysis patients during 1988 [4] and 1989 [5]. Bloembergen et al found no association between vintage and