NDT Advance Access published July 4, 2006

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1 NDT Advance Access published July 4, 2006 Nephrol Dial Transplant (2006) 1 of 7 doi: /ndt/gfl339 Original Article Starting and withdrawing haemodialysis associations between nephrologists opinions, patient characteristics and practice patterns (data from the Dialysis Outcomes and Practice Patterns Study) Mark Lambie 1, Hugh C. Rayner 1, Jennifer L. Bragg-Gresham 2, Ronald L. Pisoni 2, Vittorio E. Andreucci 3, Bernard Canaud 4, Friedrich K. Port 2 and Eric W. Young 5 1 Department of Renal Medicine, Birmingham Heartlands Hospital, Birmingham, UK, 2 Arbor Research Collaborative for Health, Ann Arbor, Michigan, USA, 3 Universita Federico II, Naples, Italy, 4 Nephrology Department, Lapeyonie University Hospital, Montpellier, France and 5 Veterans Affairs Medical Centre/University of Michigan, Ann Arbor, MI, USA Abstract Background. The incidence and prevalence of haemodialysis vary widely across countries. The variation may be attributable to differences in the incidence of end-stage renal disease and/or in the availability of haemodialysis. Previous studies have identified differences in nephrologists opinions about the availability of haemodialysis and its appropriateness for patients with comorbidities. We studied the associations between nephrologists opinions, availability of haemodialysis, patient characteristics and comorbidities, and facilities withdrawal rates. Methods. Most of our analyses used data from 242 haemodialysis units in six countries (France, Germany, Italy, Spain, UK and the USA) in the first phase of the Dialysis Outcomes and Practice Patterns Study (DOPPS I). Opinions about access to and practice patterns in dialysis facilities, measured by the level of agreement with standardized statements, were collected from medical directors and nurse managers. A sub-analysis considered data from corresponding facilities in DOPPS II. Results. We found wide variations in the prevalence of waiting lists for new dialysis patients (UK 60%; USA 25%; Germany 0%; P < 0.05), in agreement with starting haemodialysis for patients with advanced age, dementia and comorbidities (UK, France < USA < other countries; P < 0.05), and in agreement with withdrawing dialysis (other countries < UK/USA; P < 0.05). The estimated glomerular filtration rate at the start of dialysis was not significantly different in units with waiting lists. Significant associations were found between nephrologists opinions and the odds of patients being 80 years old, and between Correspondence and offprint requests to: Friedrich K. Port, MD, Arbor Research Collaborative for Health, 315 W. Huron, Suite 360, Ann Arbor, MI 48103, USA. friedrich.port@arborresearch.org opinions and the rate and relative risk of withdrawal of haemodialysis. No significant associations were found between opinions and patients comorbidities or dependency. Conclusion. Differences within and across countries in nephrologists opinions regarding starting and withdrawing haemodialysis reflect differences in access to haemodialysis and the practice of withdrawal of haemodialysis in their facilities. Keywords: access to haemodialysis; Dialysis Outcomes and Practice Patterns Study (DOPPS); end-stage renal disease; practice patterns; withdrawal of dialysis Introduction There is wide variation across countries in the number of end-stage renal disease (ESRD) patients starting haemodialysis (HD) [1 5]. In 1998, the US had an incidence of 310 dialysis patients per million population, compared with 77 per million in the UK, 148 per million in Germany and 104 per million in Italy [5]. This discrepancy may be due to differences in (a) the incidence of ESRD in each country, (b) the availability of haemodialysis facilities, (c) the willingness of patients and their families to accept this type of treatment and (d) the criteria used by nephrologists to decide whether or not to offer dialysis to individual patients. Surveys of nephrologists opinions regarding the suitability of certain patients for dialysis have shown variations both within and across countries [6,7]. For example, in a 1996 survey, nephrologists in the UK and Canada were significantly less likely than nephrologists in the USA to consider dialysis for patients with significant comorbidities, particularly dementia [7]. As yet, no study has reported on whether these differences ß The Author [2006]. Published by Oxford University Press on behalf of ERA-EDTA. All rights reserved. For Permissions, please journals.permissions@oxfordjournals.org

2 2of7 are associated with differences in the characteristics of patients starting HD in the facilities in which the nephrologists practice. Rates of withdrawal of patients from dialysis have also been shown to vary across countries and across dialysis facilities [8 13]. Differences in rates of withdrawal may result from variations in (a) the attitudes of HD patients across facilities, (b) patient comorbidities and (c) the practices of the doctors and nurses who care for dialysis patients [6]. The Dialysis Outcomes and Practice Patterns Study (DOPPS) is an international prospective, observational study of HD practices and patient outcomes [14,15]. Using data from the DOPPS Phase I and II, our study examined the associations between nephrologists opinions about the practices of starting and withdrawing haemodialysis, the characteristics of patients receiving haemodialysis, and the practice patterns of dialysis facilities in order to better understand the relative importance of these different factors in determining the actual practice and outcomes. Subjects and methods Study design and sample The design of the DOPPS is described in detail elsewhere [14]. Data for this report were collected from 20 dialysis units each in France, Italy, Spain and the UK, 21 units in Germany, and 141 units in the USA. In the UK, data were collected from 10 centre and 10 satellite units, the satellite units not being linked to DOPPS centre units. Although DOPPS was also conducted in Japan, opinions on starting and stopping HD were not collected in Japan and therefore data from Japan are not included in this analysis. A subanalysis investigating time trends in opinions also included DOPPS II data for the corresponding facilities in DOPPS I (n ¼ 129: France ¼ 15, Germany ¼ 16, Italy ¼ 20, Spain ¼ 19, UK ¼ 17 and USA ¼ 42 facilities). Questionnaires were completed by medical directors (i.e. the physicians with managerial responsibility for the units) and nurse managers (for questions regarding withdrawing patients from dialysis). Respondents were asked to indicate their level of agreement or disagreement with a series of statements about their practice. Statements were related to the service provided by the unit in the study, not the whole department. Statements were standardized and translated into local languages to allow direct comparison of opinions across countries. The units were selected at random and were stratified geographically to provide a representative sample of all units in each country. Responses from units in DOPPS I were gathered from May 1998 to October Responses from units in DOPPS II were collected between 2002 and 2004 using the same methodology. Statements in the questionnaire are shown in Table 1. To assess the relationship between nephrologists opinions and practice patterns in their units, we correlated the medical directors opinions with related patient characteristics among patients who were new started dialysis within 90 days of the start of the study to the unit. We divided and analysed the nephrologists opinions in two ways: (i) agreed vs disagreed þ neutrals, and (ii) agreed vs disagreed (excluding neutrals). Statistical analyses M. Lambie et al. Responses to statements were categorized as follows: strongly disagree, disagree, neither agree nor disagree, agree or strongly agree. A summary score was calculated for each country by multiplying the percentage of responses in each category by 100 for strongly disagree, 50 for disagree, by 0 for neither disagree nor agree (neutral), þ50 for agree and þ100 for strongly agree. Hence, summary scores range from þ100 if all units strongly agree to 100 if all units strongly disagree. A score of 0 indicates either that all of the individual units are neutral (neither agree nor disagree) or that the scores of the units that agree balance the scores of the units that disagree. The glomerular filtration rate (GFR) was calculated using the five-variable Modification of Diet in Renal Disease formula for incident patients (entering the study within 7 days of first-ever HD treatment) who had laboratory data available from before their first-ever dialysis session [16]. These data were available for 40% of the patients and were summarized at the facility level for the analysis. All analyses were performed using the SAS software, Version 9.1 (SAS Institute; Cary, North Carolina, USA). Simple means were calculated by country. Significant differences across countries in levels of agreement were tested Table 1. Statements about practices regarding the initiation and withdrawal of HD (1) We attempt to initiate dialysis on almost every patient with advanced renal failure, regardless of age, other medical problems or degree of independence. (2) We do not start dialysis treatments on patients who are very elderly. (3) We do not start dialysis treatments on patients with multiple active and serious medical problems. (4) We do not start dialysis treatments on patients who are demented but otherwise healthy. (5) We do not start dialysis treatments on patients who live in nursing homes or are otherwise not living independently. (6) Once a patient has started dialysis in our unit, we do not encourage or facilitate withdrawal from dialysis treatments. (7) We are willing to allow patients on dialysis to withdraw from dialysis treatment if they desire. (8) Estimate the percentage of patients treated with other dialysis modalities (e.g. peritoneal dialysis) due to unavailability of haemodialysis units. (9) Estimate the percentage of patients for whom you delay initiation of haemodialysis because of unavailability of haemodialysis units. (10) Is there a waiting list for new patients trying to transfer to your unit? Note: Medical directors were asked to respond to these statements by ranking their level of agreement as strongly agree, agree, neutral (neither agree nor disagree), disagree or strongly disagree. In addition, nurse-managers were included as respondents regarding statements on withdrawal from dialysis treatment.

3 Access to haemodialysis opinions and practice 3 of 7 using t-tests, while the percentages were compared using chisquare tests. Linear mixed and logistic models were used to examine the associations between nephrologists opinions about starting patients on HD and characteristics of actual patients who entered the study within 90 days of first ever dialysis treatment. A linear model was used to look at associations with the continuous variable, age, while logistic regression was used to examine the relationships between opinions and dichotomized patient characteristics. Both types of models accounted for facility clustering. Cox proportional-hazards models were used to look at associations between opinions about withdrawal of dialysis and the actual risk of withdrawal. The sandwich estimator was used to account for facility clustering. Models were adjusted for age, sex, race, and 14 summary comorbid conditions. The United States was chosen as the reference country because it fell in the middle of the range of responses for many questions and had the largest sample size. Results To explore opinions about the availability of HD treatment, medical directors were asked if they had a waiting list for new patients waiting to transfer to their unit. Table 2 shows that significantly more renal units in the UK than in the other countries reported having a waiting list for new patients; no units in Germany reported having a waiting list. The presence of a waiting list in a dialysis unit was not associated with a lower level of renal function at the first HD treatment (unadjusted mean GFR for units with waiting list ¼ 11.1 ml/min/1.73m 2, without waiting Table 2. Medical directors perception of the impact of the availability of HD resources on treatment Country Units with waiting list for new patients (%) Patients for whom you delay starting HD due to unavailability of HD facilities mean (%, range) list ¼ 10.7 ml/min/1.73m 2 ; difference in mean adjusted for facility clustering ¼ 0.5 ml/min/1.73m 2, P ¼ 0.22). Estimates of the percentage of patients for whom the start of HD is delayed or who receive another dialysis modality because HD facilities were not available were also higher in the UK, and to a lesser extent in France and the USA (Table 2). There were significant differences between countries in the summary scores of medical directors opinions regarding their facility s practice of starting dialysis in various categories of patients. The majority of medical directors in the UK disagreed or strongly disagreed (mean score of 48, in a range from 100, meaning strongly disagree, to þ100, meaning strongly agree) with the general statement, We attempt to initiate dialysis on almost every patient with advanced renal failure, regardless of age, other medical problems, or degree of independence. In contrast, the medical directors in the USA were neutral (score of 6), those in France tended to agree (score of 33), and those in other countries agreed more strongly (scores of þ 50 in Germany, þ48 in Italy and þ55 in Spain). A slightly different pattern was observed with specific questions (Table 3). Medical directors in France and the UK were least likely to start dialysis in patients with advanced renal failure and dementia or in patients with multiple active and serious medical problems. There were no significant differences between the DOPPS I and DOPPS II data (data not shown). More medical directors in the UK than in the other countries responded that they did not start HD for patients who lived in nursing homes (or who France (0 10) 5.5 (0 50)* Germany 0 0 (0 0) 0 (0 0) Italy 10 0 (0 0) 2.2 (0 22) Spain 20 0 (0 0) 0 (0 0) UK 60* 18.1 (0 80)* 10.3 (0 50)* US (0 20) 1.6 (0 51) Patients treated with other dialysis modalities (e.g. peritoneal dialysis) due to unavailability of HD facilities mean (%, range) *P < 0.05 vs USA. Table 3. Medical directors level of agreement with practices related to initiating haemodialysis Opinion Level of agreement France Germany Italy Spain UK US We do not start HD for patients who: Are demented but otherwise healthy 23* * 32 Have multiple medical problems 15* * 48 Are not independent (nursing home) * 59 Are very elderly * 61 *P < 0.05 vs USA. Values can range from 100, meaning strongly disagree, to þ100, meaning strongly agree.

4 4of7 Table 4. Medical directors opinions correlated with patient demographics M. Lambie et al. Opinion Outcome in incident patients* in facilities with medical directors who agree P-value We do not start dialysis treatment on: Patients who are very elderly (3.3% agree/96.7% neutral or disagree) Patients who are demented, but otherwise healthy (21.9% agree/78.1% neutral or disagree) Patients who live in nursing home or are not independent (4.1% agree/95.9% neutral or disagree) Patients with multiple medical problems (8.3% agree/91.7% neutral or disagree) OR (patient 80 years) ¼ OR (patient with history of dementia) y ¼ OR (patients in nursing home or who are unable to feed themselves) ¼ 1.80 OR [patient has 6 summary comorbid conditions (out of 14)] ¼ *Incident patients defined as entering the DOPPS study within 90 days of their first ever dialysis treatment. y Adjusted for 13 comorbid conditions (excludes neurological disease). All models account for facility clustering. Table 5. Level of agreement with withdrawing and not withdrawing patients from dialysis (medical directors and nurse-managers) Opinion France Germany Italy Spain UK USA Willing to allow patients to withdraw from dialysis Medical directors 33* 52 3* 43* Nurse-managers 8* 33* 20* 18* Do not encourage or facilitate withdrawal from dialysis Medical directors 30* 33* 58* 5* Nurse managers 58* 45* 55* *P < 0.05 vs USA. Values can range from 100, meaning strongly disagree, to þ100, meaning strongly agree. were otherwise not living independently) or for very elderly patients with no other major comorbidity. The percentage of patients who started dialysis within 90 days of being enrolled in the DOPPS and who were living in a nursing home or were unable to eat independently at the time of enrolment was much higher in the USA (11.6%) than in France (1.3%), Germany (6.4%), Italy (4.7%), Spain (2.0%) and the UK (1.5%). To investigate how closely medical directors opinions reflected actual practice, we analysed associations between medical directors opinions and characteristics of patients starting dialysis in each medical director s facility (Table 4). The odds of incident patients being 80 in facilities in which medical directors said that they did not start dialysis in very elderly patients were significantly lower than the odds in other facilities (odds ratio ¼ 0.61, P ¼ 0.03). Similarly, the mean age of patients in units that favoured dialysis for the elderly was 2.9 years older than in other units (P ¼ 0.14). The odds of incident patients having a history of dementia, living in a nursing home, being unable to eat independently or having 6 summary comorbid conditions were not significantly different in those facilities in which the medical directors agreed with the statements about not starting dialysis in such patients. More medical directors than nurse managers in every country agreed that they allowed withdrawal from dialysis if a patient wished to withdraw (Table 5). Similarly, more nurse managers than medical directors responded that they did not encourage or facilitate withdrawal from dialysis. There were also significant differences between countries; agreement with withdrawal was most common in the UK and the USA. Again, there were no significant differences between the DOPPS I and DOPPS II data. The rate of withdrawal was lower in units in which medical directors agreed that they did not encourage withdrawal (0.8 withdrawals/100 patient years) than in units in which medical directors were neutral or disagreed (1.4 withdrawals/100 patient years) (Table 6). The relative risk of patients having HD withdrawn was significantly lower if the medical directors said that they did not encourage withdrawal (RR ¼ 0.55, P ¼ 0.04). Similarly, there was a higher withdrawal rate (1.3 withdrawals/100 patient years) and a significantly increased relative risk of HD withdrawal [relative risk (RR ¼ 2.22, P ¼ 0.009)] if the medical directors agreed with allowing withdrawal at the patient s request than if they were neutral or did not agree (0.6 withdrawals/100 patient years; reference group). When neutral responders were excluded from the analysis, very similar results were obtained. Discussion By using a standard questionnaire translated into the local language and applied to a random sample

5 Access to haemodialysis opinions and practice 5 of 7 Table 6. Rates of withdrawal from haemodialysis at facilities, by medical director opinions Opinion Crude rates from all census patients Relative risk of withdrawal Withdrawals Patient years Withdrawals/ 100 patient years Unadjusted Adjusted* Do not encourage or facilitate withdrawal P P Agree , Neutral/do not agree , reference 1.00 reference Allow withdrawal if patient wants Agree , Neutral/do not agree 32 5, reference 1.00 reference *Adjusted for age, sex, race and diabetes status. of HD units, DOPPS is able to describe nationally representative HD practice patterns. Differences across countries in nephrologists opinions regarding which patients would usually receive HD have previously been reported from the USA, Canada and the UK [7]. This study extends these data to other European countries, examines the associations between nephrologists views of the practice patterns within their facilities and the number and characteristics of patients starting and withdrawing from HD, and surveys pressures on HD units. In this study, nephrologists in France, the UK and the USA reported an apparent inadequacy of HD capacity; facilities in these countries were more likely to operate a waiting list for new patients and to perceive delays in the initiation of HD. Also, nephrologists in these countries more frequently reported that patients started other dialysis modalities, such as peritoneal dialysis (PD), because HD was unavailable. HD capacity is affected by the supply of, and attitudes towards, other modalities. Studies examining nephrologists attitudes towards PD suggest that there is agreement that PD rates ideally should be between 29 and 38% [17 20], although in 2002, the PD rates were 27% in the UK, compared with 10% in Spain, 8% in the USA and Italy, and 5% in Germany [4]. Supply vs demand may be more important in determining the balance between PD and HD. Transplantation rates also vary widely [21]. Deceased donor rates vary from 24.4 per million population in the UK to 29.2 in Italy, 40.9 in France and 50.6 in Spain. Living donor rates (and therefore pre-emptive rates) also vary from 1.6 per million population in Spain to 2.7 in France, 2.6 in Italy, 7.8 in the UK and 21 in the USA. This variation will affect the pressure on HD units, although there is no consistent pattern in its impact across different countries. The presence of a waiting list in a dialysis facility was not associated with a lower GFR in those patients initiating HD. This suggests that waiting lists are managed such that when dialysis is started, it is timed according to the clinical severity of the renal failure. An alternative explanation for this finding could be that a difference in opinion exists between units with and without waiting lists regarding the optimum time for dialysis initiation, as variations in attitudes do exist [22]. There were significant differences across countries in nephrologists opinions about starting HD for different categories of patients (Table 3). Agreement with not starting dialysis in very elderly patients was associated with a lower mean age of incident patients and a significantly lower odds ratio for incident patients 80 years old and older. Agreement with not starting dialysis in very elderly patients was highest in the UK and is consistent with the lower age of incident patients in the UK when compared with the other European countries [23]. The percentage of incident patients living in nursing homes or being unable to eat independently was much higher in the USA than in the European countries. However, there was no difference between the views of nephrologists in the USA and in European countries other than the UK about starting dialysis in such patients. There was also no significant association between the medical directors opinions and the odds of incident patients in their facilities who were very dependent or having multiple comorbidities. This suggests that in the USA, many more patients who are very dependent or who are living in nursing homes are referred to nephrologists for consideration for dialysis. In contrast, in Europe, non-specialists make decisions about dialysis and fewer such patients are referred [24]. This study has a number of limitations that may have led to the lack of a significant result for patient comorbidity. First, the sample size of 242 nephrologists may be too small to reveal weak associations; for example, only a small percentage of nephrologists responded that they did not start dialysis in certain categories of patients. Also, the opinions expressed apply only to a small proportion of all patients starting dialysis, which may reduce the reliability of the study. Second, differences in the selection of patients who are referred to nephrologists may cause a confounding effect. Non-specialists consider dialysis to be inappropriate for more patients than nephrologists do [24], and nephrologists opinions and practice can affect only those ESRD patients who are referred

6 6of7 to them. Third, the incident population studied may have started dialysis up to 90 days prior to enrolment in the study and may have changed their place of residence (and therefore their dialysis unit) during this time, thus weakening the association. Finally, the opinions expressed might reflect nephrologists individual opinions and practice, but not those of the other clinicians in their facility. The medical directors completing the questionnaire were specifically asked to base their responses on facility practice as a whole, but this request may have proved difficult to fulfill. Furthermore, the opinions may reflect ideal rather than actual practice. Various non-clinical factors have been shown to affect physicians decisions in other specialities [25,26]; similarly, when nephrologists make decisions about starting dialysis, they may be influenced by patients, relatives and nursing staff. There was wide variation across countries in opinions about the withdrawal of dialysis treatment. Previous studies have shown higher withdrawal rates in the USA, the UK and France (6 44%) than in Italy (up to 1.1%) [8 13]. Decisions regarding withdrawal of treatment are strongly influenced by ethical, religious and legal factors that vary across countries and cultures. It is also possible that pressure on the availability of dialysis facilities for new patients may influence decisions to minimize the duration of poor quality of life of patients currently on dialysis. The statistically significant associations between nephrologists opinions regarding the withdrawal of dialysis and the rates and risk of withdrawal indicate that these opinions do reflect facility practices. In all countries, nephrologists were more willing than nurses to encourage or facilitate withdrawal. This may reflect the closer relationship that often develops between patients and their nurses. Conclusion In agreement with reported wide variations across countries in the incidence rate of treated ESRD, this study demonstrates wide variation within and between countries in nephrologists opinions regarding the starting of HD in certain categories of patients. Opinions regarding the withdrawal of HD treatment also varied widely. The differences in nephrologists opinions are associated with actual differences in incidence rates of very elderly patients starting dialysis and in the practice of withdrawal of HD within dialysis facilities. These results suggest that the incidence rates for HD treatment are affected not just by the incidence of advanced kidney failure, but also by dialysis facility practices. Acknowledgements. The Dialysis Outcomes and Practice Patterns Study is supported by a research grant from Amgen without restrictions on publications. Conflict of interest statement. None declared. References M. Lambie et al. 1. Frei U, Schober-Halstenberg H-J. 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