Search

Background During the past decade, a trend has been observed in the United States toward initiation of chronic dialysis at higher levels of estimated glomerular filtration rate. This likely reflects secular trends in the composition of the dialysis population and a tendency toward initiation of dialysis earlier in the course of kidney disease. Methods The goal of this study was to generate model-based estimates of the magnitude of changes in the timing of dialysis initiation between 1997 and 2007. We used information from a national registry for end-stage renal disease on estimated glomerular filtration rate at initiation among patients who received their first chronic dialysis treatment in 1997 or 2007. We used information regarding predialysis estimated glomerular filtration rate slope from an integrated health care system. Results After accounting for changes in the characteristics of new US dialysis patients from 1997 to 2007, we estimate that chronic dialysis was initiated a mean of 147 days earlier (95% confidence interval, 134-160) in the later compared with the earlier year. Differences in timing were consistent across a range of patient subgroups but were most pronounced for those aged 75 years or older; the mean difference in timing in that subgroup was 233 days (95% confidence interval, 206-267). Conclusions Chronic dialysis appears to have been initiated substantially earlier in the course of kidney disease in 2007 compared with 1997. In the absence of strong evidence to suggest that earlier initiation of chronic dialysis is beneficial, these findings call for careful evaluation of contemporary dialysis initiation practices in the United States.

Albuminuria is associated with an increased risk of death independent of level of renal function. Whether this association is similar for adults of all ages is not known.We examined the association between the albumin to creatinine ratio (ACR) and all-cause mortality after stratification by estimated glomerular filtration rate (eGFR) and age group in 94 934 veterans with diabetes mellitus. Cohort members had at least 1 ACR recorded in the Veterans Affairs Health Care System between October 1, 2002, and September 30, 2003, and were followed up for death through October 15, 2009.From the youngest to the oldest age group, the prevalence of an eGFR less than 60 mL/min/1.73 m(2) ranged from 11% to 41%; microalbuminuria (ACR 30-299 mg/g) ranged from 19% to 28%; and macroalbuminuria (ACRor =300 mg/g) ranged from 3.2% to 3.7%. Of patients with an eGFR less than 60 mL/min/1.73 m(2), 72% of those younger than 65 years, 74% of those 65 to 74 years old, and 59% of those 75 years and older had an eGFR of 45 to 59 mL/min/1.73 m(2). In all age groups, less than 35% of these patients had albuminuria (ie, ACRor =30 mg/g). In patients 75 years and older, the ACR was independently associated with an increased risk of death at all levels of eGFR after adjusting for potential confounders. In younger age groups, this association was present at higher levels of eGFR but seemed to be attenuated at lower levels [corrected].The ACR is independently associated with mortality at all levels of eGFR in older adults with diabetes and may be particularly helpful for risk stratification in the large group with moderate reductions in eGFR.

Background Screening guidelines recommend that mammography be targeted to women likely to live longer than 5 years. Because women undergoing dialysis have a reduced but variable life expectancy, their appropriate use of screening is controversial. Therefore, we conducted this study to describe national mammography rates among women undergoing dialysis with differing prognostic factors and to determine whether screening is targeted to healthier women who live longer. Methods Using the US Renal Data System, we identified 17 090 women aged 50 years or older who started dialysis in 1997. We tracked women for 5 years to ascertain their use of screening mammography or death. Results The 5-year survival rate was 25%. The biennial screening mammography rate was 25%, ranging from 12% for women aged 80 years or older to 69% for women who were ever on the transplant list. Women who were screened in the past year had a lower death rate than those who were not (hazards ratio, 0.55; 95% confidence interval, 0.51-0.59). Yet, 2198 women (13%) who died within 5 years underwent screening, and 2004 women (12%) who lived more than 5 years while receiving dialysis did not undergo screening. Conclusions Screening mammography rates are appropriately low among women undergoing dialysis because the 5-year survival rate is low. Screening is being targeted to women who are healthier and live longer. However, targeting could be improved by increasing screening in the few women undergoing dialysis with substantial life expectancies while decreasing screening in most women undergoing dialysis who live less than 5 years.

Background The association of cystatin C, a novel marker of renal function, with risk for developing complications related to peripheral arterial disease (PAD) has not been examined. Methods We evaluated the hypothesis that a high cystatin C concentration is independently associated with future PAD events among 4025 participants in the Cardiovascular Health Study who underwent serum cystatin C measurement at the 1992-1993 visit and who did not have PAD at baseline. The association of cystatin C quintiles with time to first lower-extremity PAD procedure (bypass surgery, angioplasty, or amputation) was evaluated using multivariable proportional hazards models. Secondary analyses were conducted using quintiles of serum creatinine level and estimated glomerular filtration rate (eGFR). Results The annualized risk of undergoing a procedure for PAD was 0.43% per year among participants in the highest cystatin C quintile (>1.27 mg/L) compared with 0.21% per year or less in all other quintiles. After multivariable adjustment for known risk factors for PAD, elevated cystatin C levels remained associated with the outcome (hazard ratio, 2.5 for highest vs lowest quintile of cystatin C, 95% confidence interval, 1.2-5.1). The highest quintiles of serum creatinine level and eGFR were not associated with future PAD events in either unadjusted or adjusted analyses. Conclusion Elevated concentrations of cystatin C were independently predictive of incident PAD events among community-dwelling elderly patients.

Background: A low ankle-brachial index (ABI) predicts risk of cardiovascular death, myocardial infarction, peripheral arterial disease events, and stroke. However, it is unknown whether a low ABI also predicts a decline in renal function. Methods:WeexaminedtheassociationbetweenABIand changeinserumcreatininelevelovertimeamong13655 participants in the Atherosclerosis Risk in Communities (ARIC) study who underwent serum creatinine and ABI measurement at baseline and also underwent serum creatinine measurement 3 years later at the second study visit. The study outcome was a 50% rise in serum creatinine level from baseline to the second study visit. Results: Overall, 0.48% of participants with an ABI of 1 or higher, 0.9% of participants with an ABI between 0.9and0.99,and2.16%ofparticipantswithanABIlower than 0.9 experienced a 50% or greater increase in serum creatininelevel.Inmultivariateanalysis,participantswith an ABI lower than0.9 were still more thantwice as likely as those in the referent category (ABI 1) to experience anincreaseinserumcreatininelevel(oddsratio2.5;95% confidence interval, 1.1-5.7) (P=.04), and a linear trend in the incidence of worsening renal function was noted across ABI categories (P=.02). Analyses excluding participants with renal insufficiency, diabetes, and hypertension at baseline all produced similar results. Conclusion: In addition to known associations of the ABI with stroke, myocardial infarction, peripheral arterial disease events, and cardiovascular death, a low ABI also predicts an increase in serum creatinine level over time. Arch Intern Med. 2005;165:1481-1485