Roger N Greenwood

Arbor Research Collaborative for Health, Ann Arbor, Michigan, United States

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Publications (24)103.37 Total impact

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    ABSTRACT: KDOQI practice guidelines recommend predialysis blood pressure <140/90 mm Hg; however, most prior studies had found elevated mortality with low, not high, systolic blood pressure. This is possibly due to unmeasured confounders affecting systolic blood pressure and mortality. To lessen this bias, we analyzed 24,525 patients by Cox regression models adjusted for patient and facility characteristics. Compared with predialysis systolic blood pressure of 130-159 mm Hg, mortality was 13% higher in facilities with 20% more patients at systolic blood pressure of 110-129 mm Hg and 16% higher in facilities with 20% more patients at systolic blood pressure of ≥160 mm Hg. For patient-level systolic blood pressure, mortality was elevated at low (<130 mm Hg), not high (≥180 mm Hg), systolic blood pressure. For predialysis diastolic blood pressure, mortality was lowest at 60-99 mm Hg, a wide range implying less chance to improve outcomes. Higher mortality at systolic blood pressure of <130 mm Hg is consistent with prior studies and may be due to excessive blood pressure lowering during dialysis. The lowest risk facility systolic blood pressure of 130-159 mm Hg indicates this range may be optimal, but may have been influenced by unmeasured facility practices. While additional study is needed, our findings contrast with KDOQI blood pressure targets, and provide guidance on optimal blood pressure range in the absence of definitive clinical trial data.
    Kidney International 06/2012; 82(5):570-80. · 8.52 Impact Factor
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    ABSTRACT: The aim of this study was to evaluate the relation between pre-nephrology visit (PNV) and 1-yr patient survival after hemodialysis (HD) induction. Data were analyzed from 8500 incident HD patients (on HD <or=30 d) in the Dialysis Outcomes and Practice Patterns Study (DOPPS) phases I and II. A visit to a nephrologist at least 1 mo before starting HD was regarded as PNV. Cox regression was used to estimate the adjusted hazard ratio (AHR) for mortality in the first year of HD in both patient- and facility-level analyses. All models were adjusted for age, sex, race, socioeconomic factors, cause of ESRD, 14 comorbid conditions, hemoglobin, serum albumin, and serum creatinine; accounted for facility clustering effects; and were stratified by country. In patient-level analysis, PNV was associated with significantly lower risk for death (AHR 0.57; P < 0.0001). Facility-level analysis also showed a significant lower risk for death in facilities with greater prevalence of PNV in both continuous models (AHR 0.92 per 10% greater facility mean %PNV; P < 0.0004) and in categorical models (AHR 0.71 for facilities with >90% of patients receiving PNV [first quartile] compared with facilities with <71% of patients receiving PNV [fourth quartile]; P = 0.001). These results provide not only patient-level but also facility practice evidence that PNV is related to improved patient survival during the first year after initiation of HD, indicating the possible mortality benefits with more increased attention to PNV.
    Clinical Journal of the American Society of Nephrology 03/2009; 4(3):595-602. · 5.07 Impact Factor
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    ABSTRACT: Retrospective studies of haemodialysis patients from large dialysis organizations in the United States have indicated that intravenous vitamin D may be associated with a survival benefit. However, patients prescribed vitamin D are generally healthier than those who are not, suggesting that treatment by indication may have biased previous findings. Additionally, no survival benefit associated with vitamin D has been shown in a recent meta-analysis in CKD patients. Because treatment-by-indication bias due to both measured and unmeasured confounders cannot be completely accounted for in standard regression or marginal structural models (MSMs), this study evaluates the association between vitamin D and mortality among participants in the Dialysis Outcomes and Practice Patterns Study (DOPPS) using standard regression and MSMs with an expanded set of covariates, as well as by instrumental variable models to minimize potential bias due to unmeasured confounders. Data from 38 066 DOPPS participants from 12 countries between 1996 and 2007 were analysed. Mortality risk was assessed using standard baseline and time-varying Cox regression models, adjusted for demographics and detailed comorbidities, and MSMs. In models similar to instrumental variable analysis, the facility percentage of patients prescribed vitamin D, adjusted for the patient case mix, was used to predict patient-level mortality. Vitamin D prescription was significantly higher in the USA compared to other countries. On average, patients prescribed vitamin D had fewer comorbidities compared to those who were not. Vitamin D therapy was associated with lower mortality in adjusted time-varying standard regression models [relative ratio (RR) = 0.92 (95% confidence interval: 0.87-0.96)] and baseline MSMs [RR = 0.84 (0.78-0.98)] and time-varying MSMs [RR = 0.78 (0.73-0.84)]. No significant differences in mortality were observed in adjusted baseline standard regression models for patients with or without vitamin D prescription [RR = 0.98 (0.93-1.02)] or for patients in facility practices where vitamin D prescription was more frequent [RR for facilities in 75th versus 25th percentile of vitamin D prescription = 0.99 (0.94-1.04)]. Vitamin D was associated with a survival benefit in models prone to bias due to unmeasured confounding. In agreement with a meta-analysis of randomized controlled studies, no difference in mortality was observed in instrumental variable models that tend to be more independent of unmeasured confounding. These findings indicate that a randomized controlled trial of vitamin D and clinical outcomes in haemodialysis patients are needed and can be ethically conducted.
    Nephrology Dialysis Transplantation 12/2008; 24(3):963-72. · 3.37 Impact Factor
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    ABSTRACT: To identify modifiable factors associated with health-related quality of life (HRQOL) among chronic hemodialysis patients. Analysis of baseline data of 9,526 hemodialysis patients from seven countries enrolled in phase I of the Dialysis Outcomes and Practice Patterns Study (DOPPS). Using the Kidney Disease Quality of Life Short Form (KDQOL-SF(TM)), we determined scores for 8 generic scale summaries derived from these scales, i.e., the physical component summary [PCS] and mental component summary [MCS], and 11 kidney disease- targeted scales. Regression models were used to adjust for differences in comorbidities and sociodemographic and treatment factors. The Benjamini-Hochberg procedure was used to correct P-values for multiple comparisons. Unemployment and psychiatric disease were independently and significantly associated with lower scores for all generic and several kidney disease-targeted HRQOL measures. Several other comorbidities, lower educational level, lower income, and hypoalbuminemia were also independently and significantly associated with lower scores of PCS and/or MCS and several generic and kidney disease-targeted scales. Hemodialysis by catheter was associated with significantly lower PCS scores, partially explained by the correlation with covariates. Associations of poorer HRQOL with preventable or controllable factors support a greater focus on psychosocial and medical interventions to improve the well-being of hemodialysis patients.
    Quality of Life Research 06/2007; 16(4):545-57. · 2.41 Impact Factor
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    ABSTRACT: Existing national, racial, and ethnic differences in dialysis patient mortality rates largely are unexplained. This study aimed to test the hypothesis that mortality rates related to atherosclerotic cardiovascular disease (ASCVD) in dialysis populations (DP) and in the background general populations (GP) are correlated. In a cross-sectional, multinational study, all-cause and ASCVD mortality rates were compared between GP and DP using the most recent data from the World Health Organization mortality database (67 countries; 1,571,852,000 population) and from national renal registries (26 countries; 623,900 population). Across GP of 67 countries (14,082,146 deaths), all-cause mortality rates (median 8.88 per 1000 population; range 1.93 to 15.40) were strongly related to ASCVD mortality rates (median 3.21; range 0.53 to 8.69), with Eastern European countries clustering in the upper and Southeast and East Asian countries in the lower rate ranges. Across DP (103,432 deaths), mortality rates from all causes (median 166.20; range 54.47 to 268.80) and from ASCVD (median 63.39 per 1000 population; range 21.52 to 162.40) were higher and strongly correlated. ASCVD mortality rates in DP and in the GP were significantly correlated; the relationship became even stronger after adjustment for age (R(2) = 0.56, P < 0.0001). A substantial portion of the variability in mortality rates that were observed across DP worldwide is attributable to the variability in background ASCVD mortality rates in the respective GP. Genetic and environmental factors may underlie these differences.
    Journal of the American Society of Nephrology 12/2006; 17(12):3510-9. · 8.99 Impact Factor
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    ABSTRACT: Little is known about proton pump inhibitor (PPI) or H(2) receptor antagonist (HA) prescription patterns or regarding use of predictors in hemodialysis patients. Proton pump inhibitor and HA prescribing patterns were investigated in 8628 hemodialysis patients from seven countries enrolled in the prospective, observational Dialysis Outcomes and Practice Patterns Study. Logistic regression examined predictors associated with PPI and HA use, adjusting for age, sex, country, time with end-stage renal disease, medications, 14 comorbid conditions, and the association between the number of comorbid conditions and the prescription of gastrointestinal (GI) medications. In a cross-section from February 1, 2000, 3.4% to 36.9% of patients received an HA and 0.8% to 26.9% took a PPI, depending upon the country. From 1996 to 2001, the prescription of HAs declined while PPI use increased. Facility use of HAs and PPIs ranged from 0% to 94% of patients. H2 receptor antagonist or PPI use was significantly and independently associated with age, narcotic use, corticosteroids, acetaminophen, nonsteroidal anti-inflammatory drugs, tricyclic antidepressants, selective serotonin reuptake inhibitors, coronary artery disease history, cardiovascular diseases other than hypertension or congestive heart failure, peripheral vascular disease, pulmonary disease, and GI bleed. Proton pump inhibitors or HAs were more likely to be prescribed in Italy, Spain, and the United Kingdom than in the United States. The odds of PPI prescription increased if serum phosphorus <5.5 mEq/L or serum albumin <3.5 g/dL. Prescription of GI medications was associated with many comorbidities and use of several medications. Extreme variability of prescription patterns suggests that there is no standard approach in treatment practices.
    Hemodialysis International 05/2006; 10(2):180-8. · 1.44 Impact Factor
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    ABSTRACT: To survey of the structure, processes and organisation of renal satellite units (RSUs) in England and Wales (Phase 1), and to compare the effectiveness, acceptability, accessibility and economic impact of chronic haemodialysis performed in RSUs compared to main renal units (MRUs) (Phase 2). Phase 1: all renal satellite units in England and Wales. Phase 2: haemodialysis patients in a representative sample (based on geography, site, private--public ownership, medical input) of 12 RSUs and their MRUs. Phase 1 consisted of a questionnaire survey. Semi-structured interviews were held in a representative sample of 24 RSUs with the senior clinician, senior nurse and manager. Phase 2 consisted of a cross-sectional comparison of patients in these RSUs and patients in the parent MRUs deemed suitable for satellite care by senior staff. Clinical information was obtained from medical notes and unit computer systems. Generic and disease specific health-related quality of life (HRQoL) measures were used. Co-morbidity was assessed by the Wright/Khan Index, the Lister/Chandna score, the Modified Charlson Index, and the Karnofsky Performance Score. Statistical analyses compared RSU versus MRU patients and took account of the paired and clustered nature of the data. In Phase 1, responses were received from 74/80 (93%) of RSUs; 2600 patients were being treated in these RSUs. The interviews were generally positive about the impact of RSUs in terms of improved accessibility and a better environment for chronic haemodialysis (HD) patients, and in expanding renal replacement therapy patients (RRT) capacity. In Phase 2, some 82% of eligible patients took part, 394 patients in the 12 RSUs and 342 in the parent MRUs. The response rate was similar in both groups. There were no significant differences in clinical processes of care. Most clinical outcomes were similar, especially after pooled analysis, although a few parameters were statistically significantly different -- notably the proportion achieving Renal Association Standards for adequacy of dialysis as measured by the urea reduction ratio (URR) was higher in the RSU patients. Patient-specific quality of life did not differ except on the patient satisfaction questions from the KDQOL, which were scored higher by the RSU sample. Strength of preference for health status on and off dialysis was very similar between the groups, as were EQ-5D utilities. Major adverse events were not common in the RSU patients, although there were many hypotensive episodes on HD, a proportion of which affected the duration of the HD session. Of the costs measured, the only difference that was statistically significant was for District Nurse visits. Of particular note was that despite the MRU group having a higher proportion of patients hospitalised, this did not translate into a statistically significant budgetary impact in terms of the total cost per patient of hospitalisations or mean cost per patient per hospitalisation. This study has shown that RSUs are an effective alternative to MRU HD for a wide spectrum of patients. They improve geographic access for more dispersed areas and reduce patients' travel time, and are generally more acceptable to patients on several criteria. There does not seem to be an adverse impact of care in the RSUs although comparative long-term prospective data are lacking. The evidence suggests that satellite development could be successfully expanded; not all MRUs have any satellites and many have only a few. No single RSU model can be recommended but key factors would include local geography, the likely catchment population and the type of patients to be treated. There is a need for more basic budgetary information linking activity and expenditure to be available and more transparent, to perform at least an insightful top-down costing of the two care settings. Other areas suggested for further research include: a comparison of adverse events occurring in MRUs and RSUs with longer duration and larger numbers to identify more severe events, along with the more research into the scope for preventing such events, and a study into the patients deemed ineligible for satellite care. International comparisons of satellite care would also be useful.
    Health technology assessment (Winchester, England) 08/2005; 9(24):1-178. · 4.03 Impact Factor
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    ABSTRACT: The cause of the increase in core temperature (CT) during hemodialysis (HD) is still under debate. It has been suggested that peripheral vasoconstriction as a result of hypovolemia, leading to a reduced dissipation of heat from the skin, is the main cause of this increase in CT. If so, then it would be expected that extracorporeal heat flow (Jex) needed to maintain a stable CT (isothermic; T-control = 0, no change in CT) is largely different between body temperature control HD combined with ultrafiltration (UF) and body temperature control HD without UF (isovolemic). Consequently, significant differences in DeltaCT would be expected between isovolemic HD and HD combined with UF at zero Jex (thermoneutral; E-control = 0, no supply or removal of thermal energy to and from the extracorporeal circulation). During the latter treatment, the CT is expected to increase. In this study, changes in thermal variables (CT and Jex), skin blood flow, energy expenditure, and cytokines (TNF-alpha, IL-1 receptor antagonist, and IL-6) were compared in 13 patients, each undergoing body temperature control (T-control = 0) HD without and with UF and energy-neutral (E-control = 0) HD without and with UF. CT increased equally during energy-neutral treatments, with (0.32 +/- 0.16 degrees C; P = 0.000) and without (0.27 +/- 0.29 degrees C; P = 0.006) UF. In body temperature control treatments, the relationship between Jex and UF tended to be significant (r = -0.51; P = 0.07); however, there was no significant difference in cooling requirements regardless of whether treatments were done without (-17.9 +/- 9.3W) or with UF (-17.8 +/- 13.27W). Changes in energy expenditure did not differ among the four treatment modes. There were no significant differences in pre- and postdialysis levels of cytokines within or between treatments. Although fluid removal has an effect on thermal variables, no single mechanism seems to be responsible for the increased heat accumulation during HD.
    Journal of the American Society of Nephrology 07/2005; 16(6):1824-31. · 8.99 Impact Factor
  • Ronald L Pisoni, Roger N Greenwood
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    ABSTRACT: The Dialysis Outcomes and Practice Patterns Study (DOPPS) is a prospective, observational study of the relationships between hemodialysis (HD) patient outcomes and HD treatment practices. The DOPPS began in 1996 in the United States, expanding to France, Germany, Italy, Japan, Spain, and the United Kingdom in 1998-1999, and then to Australia, Belgium, Canada, New Zealand, and Sweden in 2002. More than 300 dialysis units have participated in the DOPPS since 1996, with mortality data collected from nearly 90,000HD patients and detailed longitudinal data from nearly 30,000 HD patients. Large sample size and the large treatment practice variation observed in the DOPPS--given its international scope of participation--provide strong statistical power to investigate many different HD practices. Furthermore, the detailed patient data collected in the DOPPS allow relationships to account for differences in a large number of patient characteristics. More than 55 papers have been published from the DOPPS; here we provide a summary of selected DOPPS findings regarding nutrition, mineral metabolism, anemia management, vascular access, depression, and use of multivitamins and statins.
    Contributions to nephrology 02/2005; 149:58-68. · 1.49 Impact Factor
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    ABSTRACT: Medications affect many measures of hemodialysis patients' well-being. The Dialysis Outcomes and Practice Patterns Study (DOPPS) has evaluated the use of hydroxymethyl glutaryl coenzyme A reductase inhibitors (statins), analgesics, antidepressants, and multivitamins. Additionally, DOPPS has reported on the associations between vascular access outcomes and related medications. Prescription of statins varied widely across countries, with the highest use in the United States. Patients prescribed statins had lower risk of cardiac and noncardiac causes of mortality than those who were not prescribed statins. DOPPS data also show that statins are underprescribed relative to recent Kidney Disease Outcomes Quality Initiative guidelines. No guidelines have been established for analgesic use, but high pain levels self-reported by hemodialysis patients suggest opportunities for improved pain management strategies. Guidelines for analgesic use in dialysis patients may help balance improved quality of life against potential side effects of analgesics. Medical and patient questionnaires show that depression in hemodialysis patients is common, frequently underdiagnosed, usually untreated, and associated with increased rates of mortality and hospitalization. Calcium channel blockers were associated with improved primary graft patency, aspirin with improved secondary graft patency, and angiotensin-converting enzyme inhibitors with improved secondary fistula patency. All 3 medications were associated with significantly decreased relative risk for access failure. There is large country variation in multivitamin use, with significantly higher use in the United States compared with Europe and Japan. Patients taking multivitamins had lower mortality risk than patients not taking multivitamins. DOPPS findings on medications indicate that prospective trials are needed before guidelines can be developed for appropriate medication use in these different therapeutic categories.
    American Journal of Kidney Diseases 12/2004; 44(5 Suppl 2):61-7. · 5.29 Impact Factor
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    ABSTRACT: The prevalence rate of renal replacement therapy in the United Kingdom has increased significantly, particularly by long-term hemodialysis (HD) therapy in renal satellite units (RSUs). These are largely nurse-run units linked to main renal units (MRUs). We compared outcomes, processes of care, and costs in RSUs with those in MRUs. A cross-sectional comparison was performed of HD patients from a representative sample of 12 RSUs in England and Wales and HD patients in the linked MRUs deemed suitable by the senior nurse for RSU care. Data for patient characteristics, clinical process and outcome measures, health-related quality of life (HRQoL), and patient satisfaction were collected. A partial analysis of National Health Service and social care costs was undertaken. Geographic access was assessed by road time and distance traveled to dialysis sessions. Seven hundred thirty-six of 895 eligible patients (82%) participated. RSU patients were older (mean age, 63 versus 57 years), but had comorbidity similar to that of MRU patients. There were no significant differences in most processes of care or clinical outcomes; achievement of standards for adequacy of dialysis (urea reduction ratio) was significantly greater in RSU patients and hospitalization in the last year was less frequent. Patient HRQoL was similar, but patient satisfaction was greater in RSU patients. RSU patients potentially saved 19 minutes traveling for each dialysis session. Costs for routine dialysis and health/social care were similar. RSUs appear to be as effective as main HD units for a wide spectrum of patients, improve geographic access, and are more acceptable to patients. There is evidence that they are as cost-effective as main units.
    American Journal of Kidney Diseases 08/2004; 44(1):121-31. · 5.29 Impact Factor
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    ABSTRACT: Hepatitis C virus (HCV) remains a problem within hemodialysis units. This study measures HCV prevalence and seroconversion rates across seven countries and investigates associations with facility-level practice patterns. The study sample was from the Dialysis Outcomes and Practice Patterns Study (DOPPS), a prospective, observational study of adult hemodialysis patients randomly selected from 308 representative dialysis facilities in France, Germany, Italy, Japan, Spain, the United Kingdom, and the United States. Logistic regression was used to model odds of HCV prevalence, and Cox regression was used to model time from study entry to HCV seroconversion. Mean HCV facility prevalence was 13.5% and varied among countries from 2.6% to 22.9%. Increased HCV prevalence was associated with longer time on dialysis, male gender, black race, diabetes, hepatitis B (HBV) infection, prior renal transplant, and alcohol or substance abuse in the previous 12 months. Approximately half of the facilities (55.6%) had no seroconversions during the study period. HCV seroconversion was associated with longer time on dialysis, human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS), HBV infection, and recurrent cellulitis or gangrene. An increase in highly trained staff was associated with lower HCV prevalence (OR = 0.93 per 10% increase, P= 0.003) and risk of seroconversion (RR = 0.92, P= 0.07). Seroconversion was associated with an increase in facility HCV prevalence (RR = 1.36, P < 0.0001), but not with isolation of HCV-infected patients (RR = 1.01, P= 0.99). There are differences in HCV prevalence and rate of seroconversion at the country and the hemodialysis facility level. The observed variation suggests opportunities for improved HCV outcomes.
    Kidney International 07/2004; 65(6):2335-42. · 8.52 Impact Factor
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    ABSTRACT: The Dialysis Outcomes and Practice Patterns Study (DOPPS) is a prospective, observational study designed to evaluate practice patterns in random samples of haemodialysis facilities and patients across three continents. Participating countries include France, Germany, Italy, Spain and the UK (Euro-DOPPS), Japan and the USA. DOPPS data collection has used the same questionnaires and protocols across all participating countries to assess components of dialysis therapy and outcomes. This study focuses on dialysis prescription, adherence and nutrition among the Euro-DOPPS countries. In each Euro-DOPPS country, patients were selected randomly from 20-21 representative facilities. Simple means and frequencies were calculated to compare relevant data elements to gain insights into differences in therapeutic aspects among nationally representative patients. Participants entering the study within 90 days of beginning dialysis therapy were excluded from these analyses. Among the five countries, mean delivered dose as measured by normalized urea clearance (Kt/V) varied from 1.28 to 1.50 and was accompanied by differences in dialysis prescription components, including blood flow rates, treatment times, and dialyser membrane and flux characteristics. By country, a nearly 2-fold difference was observed in indicators of patient adherence and management (skipping and shortening dialysis, hyperkalaemia, hyperphosphataemia and high interdialytic weight gain). Indicators of malnutrition varied substantially. This study demonstrates differences in the management of haemodialysis patients across Euro-DOPPS and offers opportunities for improving dialysis dose, adherence and nutrition. Correlation of differences in practice patterns at the dialysis unit level with patient outcomes will offer new insights into improving dialysis therapy.
    Nephrology Dialysis Transplantation 02/2004; 19(1):100-7. · 3.37 Impact Factor
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    ABSTRACT: Current concepts of dry weight (DW) prescription are largely based on clinical symptoms because of the difficulty in assessing extracellular fluid volume (ECV) during dialysis. Intradialytic changes in ECV can be recorded as changes in extracellular resistance [Re] by continuous regional calf multifrequency bioimpedance spectroscopy (BIS). We hypothesized that relative changes in calf Re (Re at time '0' over Re at time 't' [R(e-0)/R(e-t)]) will become very small when ECV is reduced towards normal and individual dry weight is reached. Intradialytic continuous calf BIS was recorded repeatedly in 15 hemodialysis (HD) patients. The first measurement was performed at the prevailing clinical dry weight (CDW). Next measurements were made after post-HD body weight was gradually decreased by 0.2-0.3 kg per treatment. This procedure was iterated over several subsequent treatments until a treatment was observed where changes in R(e-0)/R(e-t) were < 1%. The weight at the end of this treatment was defined as "achieved dry weight (ADW)". Each R(e-0)/R(e-t) curve was fitted using a Matlab program (curve fitting toolbox) to obtain the exact weight at 20 min after beginning of the flattening of the R(e-0)/R(e-t) slope ('dry' weight estimated from BIS, DW-BIS). Both mean ADW (80.5 +/- 34.1 kg) and mean DW-BIS (80.6 +/- 34.1) were significantly lower than CDW (81.4 +/- 32.0 kg, p < 0.001), but there was no difference between ADW and DW-BIS. However, the average weight reduction from CDW to ADW (0.80 +/- 0.15 kg) was significantly higher than from CDW to DW-BIS (0.66 +/- 0.14 kg, p < 0.001, paired t-test). When ADW was achieved, pre-dialysis systolic blood pressure (SBP) was lower than at CDW (139.3 +/- 32.5 mmHg, vs. 129.4 +/- 33 mmHg, p < 0.05), post-HD SBP did not differ. The incidence of clinical symptoms of underhydration was similar at CDW (15%) and DW-BIS (15%), but higher at ADW (46%). Intradialytic continuous calf BIS allows the assessment of changes in extracellular calf resistance as an indicator of changes in extracellular fluid volume. Recording of a continuous R(e-0)/R(e-t) slope during dialysis appears to be a promising new tool for the prediction of dry weight in hemodialysis patients.
    The International journal of artificial organs 02/2004; 27(2):104-9. · 1.76 Impact Factor
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    ABSTRACT: The Dialysis Outcomes and Practice Patterns Study (DOPPS) is a prospective, observational study based on data collected from nationally representative samples of haemodialysis facilities. The burden of anaemia in haemodialysis patients is substantial, leading to considerable morbidity, mortality and reduced quality of life. This study examines anaemia management and outcomes based on data from five European countries participating in the DOPPS: France, Germany, Italy, Spain and the UK. Baseline data on demographics, co-morbidities and anaemia management in 4591 haemodialysis patients from 101 nephrology facilities were collected in 1998-2000. Using multivariate Cox survival analyses to adjust for patient characteristics, relationships between haemoglobin concentration at study entry and rates of mortality and hospitalization were evaluated. For a year 2000 sample of prevalent patients on haemodialysis >180 days, mean haemoglobin concentration was 11.0 g/dl; 53% had a haemoglobin concentration > or = 11 g/dl [1998-1999 = 44% (P < 0.05)]. In 2000, 84% of prevalent patients were prescribed recombinant human erythropoietin (rHuEpo). Higher haemoglobin concentrations were associated with decreased relative risk (RR) for mortality (RR = 0.95 for every 1 g/dl higher haemoglobin, P = 0.03) and hospitalization (RR = 0.96, P = 0.02). Patients with haemoglobin <10 g/dl were 29% more likely to be hospitalized than patients with haemoglobin 11-12 g/dl (P < 0.001). Even after adjustment, lower haemoglobin concentrations were associated with higher morbidity and mortality in European haemodialysis patients. A trend to increased haemoglobin concentrations was observed following publication of the European Best Practice Guidelines (EBPG) on anaemia management for chronic kidney disease patients, but efforts must continue to achieve EBPG goals.
    Nephrology Dialysis Transplantation 01/2004; 19(1):121-32. · 3.37 Impact Factor
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    ABSTRACT: The correction of anemia using erythropoeitin (EPO) is accorded high priority in the management of patients undergoing hemodialysis (HD). Target hemoglobin (Hb) levels have been established in many countries. Following an observation that the mean facility EPO dose in a chain of facilities in the United States varied by more than two-fold, an examination of the practice of anemia correction in other settings was carried out. We reviewed demographic and laboratory parameters in prevalent HD patients in 50 United States facilities and in a single HD facility in Vicenza, Italy. The mean EPO dose profile of the United States facilities was compared with the profiles in 10 facilities in the eastern United Kingdom (UKER) and in 20 facilities reporting to the United Kingdom Renal Registry (UKRR). Analysis of the factors that correlate with EPO resistance was carried out using the United States and Italian data. The average EPO doses, by facility, in the 51 United States, the 10 UKER, and the 19 UKRR facilities were 19,569, 8,416, and 7,992 international units per week (IU/wk), respectively. While examination of the UKRR revealed a similar degree of inter-facility variation (2.6-fold), much larger doses of EPO were being administered in the United States patients, particularly in the low Hb group. Multivariate analysis of the United States data suggested that factors related to inflammation, including low albumin, the use of tunneled catheters for vascular access, and low protein catabolic rate (enPCR) correlated with low Hb and relative EPO resistance. Despite similar guidelines for anemia management, significant differences in practice are observed. While there seems to be a reluctance to administer large EPO doses to individual patients in Europe, this does not seem to apply in the United States, where more EPO is given. EPO resistance seems relative rather than absolute in many patients, allowing some to respond to the higher doses.
    Kidney international. Supplement 12/2003;
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    ABSTRACT: Erythropoeitin dose variation in different facilities in different countries and its relationship to drug resistance.Background The correction of anemia using erythropoeitin (EPO) is accorded high priority in the management of patients undergoing hemodialysis (HD). Target hemoglobin (Hb) levels have been established in many countries. Following an observation that the mean facility EPO dose in a chain of facilities in the United States varied by more than two-fold, an examination of the practice of anemia correction in other settings was carried out.
    Kidney International 10/2003; · 8.52 Impact Factor
  • Nathan Levin, Roger Greenwood
    Nephrology Dialysis Transplantation 07/2003; 18(6):1059-60. · 3.37 Impact Factor
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    ABSTRACT: The usefulness of regional bioimpedance analysis (RBIA) in determining the dry weight in dialysis patients is currently being investigated. The aim of this study was to evaluate the reproducibility of measurement of resistivity in the calf. Twenty-five normal subjects and 10 patients undergoing regular hemodialysis were studied. Four electrodes inserted into a blood pressure cuff were placed on the calf. Bioimpedance was continuously measured over 3- to 5-min periods (Xitron Hydra). After a resting period of 1 min, cuff pressure was increased to above the systolic blood pressure (SBP) for a few seconds to expel excess ECF fluid and then deflated. The effect on recordings of moving the electrodes 2 cm higher and then 2 cm lower than the normal position was studied in 8 normal subjects. In a second study of reproducibility, post-dialysis measurements were made twice in 10 patients who maintained the same post-dialysis target weight throughout the study period. The mean resting resistivity rho(0) in normal subjects was 532.6 +/- 95 omega.cm rising to 583.9 +/- 99.7 omega.cm when cuff pressure was applied rho(p). The average values of rho(0) and rho(p) in patients post-dialysis were 489 +/- 74 and 537 +/- 77 respectively showing that there were no significant differences in rho(0) and rho(p) between normal subjects and patients post-dialysis. The mean values of change in resistivity when the electrodes were shifted between the lowest and highest positions on the calf were -3.66 +/- 4.45 and -1.44 +/- 3.82%, respectively. Repeat measurement of resistivity in patients post-dialysis varied by 2.04 +/- 2.29% while post-dialysis body weight varied by 0.17 +/- 0.47%. In this study, resistivity measurement by RBIA at the calf showed similar levels of fluid loading in patients post-dialysis as in normal subjects. This study also showed that change in electrode position resulted in a mean change in resistivity of <5% and repeated measurements showed a change in resistivity <3% while body weight changes were <0.2%. This technique appears to have an acceptable level of reproducibility for its application to the assessment of patient hydration.
    Blood Purification 02/2003; 21(1):131-6. · 2.06 Impact Factor
  • Asaio Journal - ASAIO J. 01/2003; 49(2).

Publication Stats

1k Citations
103.37 Total Impact Points

Institutions

  • 2012
    • Arbor Research Collaborative for Health
      Ann Arbor, Michigan, United States
  • 2004–2012
    • The Lister Hospital
      Londinium, England, United Kingdom
    • University of Naples Federico II
      Napoli, Campania, Italy
    • Ruhr-Universität Bochum
      Bochum, North Rhine-Westphalia, Germany
  • 2005–2008
    • Concordia University–Ann Arbor
      Ann Arbor, Michigan, United States
    • Maastricht University
      • Interne Geneeskunde
      Maastricht, Provincie Limburg, Netherlands
  • 2007
    • Universidade Federal da Bahia
      Bahia, Estado de Bahía, Brazil
  • 2003–2006
    • Renal Research Institute
      New York City, New York, United States
  • 2003–2004
    • Beth Israel Medical Center
      New York City, New York, United States