National haemodialysis guidelines: an assessment of compliance from 2001-2003

AIM

The Caring for Australians with Renal Impairment (CARI) clinical practice guidelines were established in 2000 to provide recommended ranges for parameters associated with anaemia management in patients with chronic kidney disease. This study used data from the Renal Anaemia Management (RAM) database to determine the level of compliance with the CARI Guidelines in Australia since their implementation.

METHODS

De-identified data from haemodialysis patients at 15 dialysis centres were obtained from the RAM database provided by Janssen-Cilag Pty Ltd, Australia. Validated data were extracted over 6 months (April-September) in 2001 (n = 2586 patients) and 2003 (n = 3190 patients). The percentage of patients with biochemical and haematological parameters that were within the ranges recommended in the CARI Guidelines was compared from 2001-2003.

RESULTS

There was a significant increase in the number of patients with values within the recommended ranges for serum ferritin, phosphate, calcium phosphate product and urea reduction ratio from 2001-2003. There was no change in the proportion of patients with values within the recommended ranges for haemoglobin, transferrin saturation, calcium or parathyroid hormone. There was considerable variation in compliance with recommended ranges between and within individual dialysis centres. Compliance to the target haemoglobin level (> or =110 g/L) ranged from 42-78% of patients at different centres in 2003.

CONCLUSION

Although the number of patients with values within those recommended in the CARI guidelines has increased for some parameters, many patients in Australia have clinical parameters outside the ranges recommended in the CARI Guidelines.

Australian nephrologists' attitudes towards living kidney donation

BACKGROUND

The demand for deceased donor kidneys far outweighs the supply. The rate of living kidney donation (LKD) has been steadily increasing world-wide and is associated with excellent outcomes for the recipient. With respect to donors' outcomes, however, a strong evidence base is lacking. This study explores the attitudes and perceptions of Australian nephrologists towards LKD, specifically regarding donor risk, their willingness to recommend LKD and their own preparedness to become a live donor.

METHODS

A postal survey of Australian nephrologists was conducted. Responses to six multiple choice questions about LKD were collected as a separate focus of a larger study.

RESULTS

We achieved a survey response rate of 52.4% and analysed responses from 184 practicing nephrologists and trainees. Australian nephrologists and trainees were generally supportive of LKD. The vast majority (95%) of respondents indicated that they would recommend it to a suitable donor or would themselves (97%) donate a kidney to an immediate family member. However, fewer than half (43%) would recommend LKD to a potential donor, where their relative's end-stage kidney disease (ESKD) had been attributed to diabetes and where there was a strong family history of diabetes. A minority thought that LKD increased the donor's risk of mortality (12%) or of ESKD (25%). Few nephrologists (4%) indicated their preparedness to be an altruistic donor--to a recipient unknown to them.

CONCLUSIONS

Although LKD is clearly supported by the nephrologists, the increasing incidence of ESKD attributable to diabetes, now the leading cause of ESKD in Australia, might, however, progressively limit its use. Meeting the growing demand for kidney transplantation will require an increased supply of both live and deceased donor kidneys. We should develop, evaluate and implement best-practice approaches to achieve this.

Chronic kidney disease and automatic reporting of estimated glomerular filtration rate: a position statement

The systematic staging of chronic kidney disease (CKD) by glomerular filtration measurement and proteinuria has allowed the development of rational and appropriate management plans. One of the barriers to early detection of CKD is the lack of a precise, reliable and consistent measure of kidney function. The most common measure of kidney function is currently serum creatinine concentration. It varies with age, sex, muscle mass and diet, and interlaboratory variation between measurements is as high as 20%. The reference interval for serum creatinine concentration includes up to 25% of people (particularly thin, elderly women) who have an estimated glomerular filtration rate (eGFR) that is significantly reduced (< 60 mL/min/1.73 m). The recent publication of a validated formula (MDRD) to estimate GFR from age, sex, race and serum creatinine concentration, without any requirement for measures of body mass, allows pathology laboratories to "automatically" generate eGFR from data already acquired. Automatic laboratory reporting of eGFR calculated from serum creatinine measurements would help to identify asymptomatic kidney dysfunction at an earlier stage. eGFR correlates well with complications of CKD and an increased risk of adverse outcomes such as cardiovascular morbidity and mortality. We recommend that pathology laboratories automatically report eGFR each time a serum creatinine test is ordered in adults. As the accuracy of eGFR is suboptimal in patients with normal or near-normal renal function, we recommend that calculated eGFRs above 60 mL/min/1.73 m be reported by laboratories as "> 60 mL/min/1.73 m", rather than as a precise figure.

Prediction of failure of native arteriovenous fistulas using 'on-line' fistula flow measurements

BACKGROUND

Measurement of blood flow within native arteriovenous fistula during haemodialysis is recommended to detect incipient fistula failure. In the present study the value of such flow measurements was assessed in a group of patients on maintenance haemodialysis, with access via native arteriovenous fistulas.

METHODS

Flow was measured using the 'on-line' thermodilution technique, on three separate occasions, and correlated with subsequent fistula failure within 6 months.

RESULTS

Of the 53 patients studied, there were six failures (three thromboses and three inadequate dialysis filtration rates). Flow rates in patients who progressed to fistula failure were significantly less than flow rates in patients whose fistulas did not fail (U = 13.0, P < 0.0003). Failure was no more common in one type of fistula than another (type fistula: F = 0.29, P = 0.88; flow predicting failure: F = 7.22, P = 0.010). Receiver operating characteristic (ROC) curve analyses confirmed flow measurement to be a useful predictor of fistula failure (area under ROC curve 0.91). The optimal threshold of 576 mL/min flow gave a sensitivity of 89% and a specificity of 81%. Measurement of access resistance was less useful in predicting failure (area under ROC curve 0.87). Measurement of fall in flow from the previous measurement was of no use (area under ROC curve 0.535).

CONCLUSION

On-line thermodilution measurement of flow within established native arteriovenous fistula is useful in surveillance and early prediction of fistula failure. Fistula flow <576 mL/min may indicate incipient native fistula failure, and should prompt further investigation.

Implementing a multidisciplinary approach to comprehensive critical care

Following recent government recommendations on critical care services, the skills and training opportunities within the critical care environment should be shared with staff on the general wards. This article discusses a one-day study course offered at one NHS trust that was developed to address the educational needs of staff working on general wards.

Barriers to access by Indigenous Australians to kidney transplantation: The IMPAKT study

Although Indigenous Australians represent less than 2% of the national population, they account for 8-10% of new patients commencing treatment for end-stage renal disease (ESRD). Almost half come from remote regions lacking renal disease treatment services. In those regions, their incidence of ESRD is up to 30 times the incidence for all Australians. Kidney transplantation is the optimal treatment for ESRD. Compared with long-term dialysis, it results in better quality of life, longer life expectancy and lower costs of health care. Indigenous Australians with ESRD receive transplants at approximately one-third the rate of non-Indigenous patients. There are similar disparities in access to kidney transplants for Native Americans, Aboriginal Canadians and New Zealander Maori. The reasons for such disparities have not been studied in any detail. IMPAKT (Improving Patient Access to Kidney Transplantation) is an NHMRC-funded study, involving eight major renal units. It aims to identify the reasons for Indigenous Australians' poor access to transplantation. It will systematically examine each of the steps a new dialysis patient must negotiate in order to receive a transplant. Each of these steps can become a barrier.

Late referral to a nephrologist reduces access to renal transplantation

BACKGROUND

Primary care physicians frequently request consultation with a nephrologist late in the treatment of patients with chronic kidney disease (CKD). Between 25% and 40% of referred CKD patients need renal replacement therapy (RRT) within 3 months of referral to a nephrologist. Late referral is associated with higher morbidity and worse long-term survival rates. The authors examined the effect of late referral on access to renal transplantation.

METHODS

Data from the Australian end-stage renal disease (ESRD) registry (Australia and New Zealand Dialysis and Transplant Registry Database [ANZDATA]) regarding all ESRD patients aged 18 to 64, starting treatment between April 1995 and December 1998 were used. Excluding overseas visitors and patients commencing RRT outside Australia, the data encompassed 3,310 patients. Main outcome measures were: (1) acceptance onto a waiting list, (2) receipt of a transplant before March 31, 2000, and/or (3) receipt of a transplant during defined periods of RRT.

RESULTS

Late referral patients were less likely to be put on the waiting list (odds ratio [OR], 0.49; 95% confidence intervals [CI], 0.41 to 0.59) or given a transplant (hazard ratio, 0.65; 95% CI, 0.55 to 0.77). Transplantation rates differed maximally during the first 3 months of RRT (OR, 0.21; 95% CI, 0.11 to 0.40) and were lower throughout RRT (OR in the period more than 2 years after commencing RRT, 0.67; 95% CI, 0.47 to 0.96).

CONCLUSION

Primary care physicians should refer patients at risk for ESRD earlier than is current practice. To improve access to transplantation and to achieve optimal outcomes of ESRD management, greater collaboration will be needed between primary care physicians and nephrologists.

Exploring the pathways leading from disadvantage to end-stage renal disease for Indigenous Australians

Indigenous Australians are disadvantaged, relative to other Australians, over a range of socio-economic and health measures. The age- and sex-adjusted incidence of end-stage renal disease (ESRD)--the irreversible preterminal phase of chronic renal failure--is almost nine times higher amongst Indigenous than it is amongst non-indigenous Australians. A striking gradient exists from urban to remote regions, where the standardised ESRD incidence is from 20 to more than 30 times the national incidence. We discuss the profound impact of renal disease on Indigenous Australians and their communities. We explore the linkages between disadvantage, often accompanied by geographic isolation, and both the initiation of renal disease, and its progression to ESRD. Purported explanations for the excess burden of renal disease in indigenous populations can be categorised as: primary renal disease explanations;genetic explanations;early development explanations; and socio-economic explanations. We discuss the strengths and weaknesses of these explanations and suggest a new hypothesis which integrates the existing evidence. We use this hypothesis to illuminate the pathways between disadvantage and the human biological processes which culminate in ESRD, and to propose prevention strategies across the life-course of Indigenous Australians to reduce their ESRD risk. Our hypothesis is likely to be relevant to an understanding of patterns of renal disease in other high-risk populations, particularly indigenous people in the developed world and people in developing countries. Furthermore, analogous pathways might be relevant to other chronic diseases, such as diabetes and cardiovascular disease. If we are able to confirm the various pathways from disadvantage to human biology, we will be better placed to advocate evidence-based interventions, both within and beyond the scope of the health-care system, to address the excess burden of renal and other chronic diseases among affected populations.

Urban disadvantage and delayed nephrology referral in Australia

This paper explores the relationship between area level measures of social disadvantage and the late referral of patients with end-stage renal disease (ESRD) to a nephrologist. Patients who were referred late were those who needed to commence dialysis within 3 months of referral to a nephrologist. Late referral has been associated with increased morbidity and mortality. We studied 3334 patients who started ESRD treatment in Australian capital cities between 1 April 1995 and 31 December 1998. The proportion referred late varied between areas, was higher in areas of greater disadvantage and was significantly related to the age- and sex-standardised incidence of ESRD. This may indicate inequitable access to optimal pre-ESRD care.

Confidence limits of arteriovenous fistula flow rate measured by the "on-line" thermodilution technique

BACKGROUND

A method is presented for estimating the confidence limits (CLs), or accuracy, of the arteriovenous fistula flow rate measured at haemodialysis by the "on-line" thermodilution technique.

METHODS

This was by derivation of an expression to estimate what variance a set of repeated measures of flow would yield, using values pertaining to a single measure of flow. (Laws of variance were applied to the formula used to calculate flow, to account for its variables' values and measurement errors.) This enabled CLs of a single measure to be estimated.

RESULTS

The variance estimated from a single measure was compared with that actually observed upon immediately taking a second measurement; differences in 189 pairs were not significantly different from zero (P=0.56). Applying the results demonstrated that measured flow values of 430-570 ml/min typically had associated 95% CLs that included 500 ml/min; therefore, true flow could not be said to be either side of 500 ml/min. The same was the case for 500-700 ml/min with regard to 600 ml/min. CLs widened considerably with the magnitude of flow rate, limiting the accurate measurement of higher flows and the detection of falls in flow.

CONCLUSION

A method to estimate CLs of flow rate measured by the thermodilution technique is presented and validated. Application demonstrates an accurate measurement of low flow, but limitations at higher flow and in detecting falls in flow. Appreciating the magnitude of such is critical to informed clinical decision making when using flow rate in an access surveillance programme.

Renal transplantation for Indigenous Australians: identifying the barriers to equitable access

OBJECTIVE

To assess Indigenous Australians' access to renal transplantation, compared with non-Indigenous Australians. To examine whether disparities are due to a lower rate of acceptance onto the waiting list and/or a lower rate of moving from the list to transplantation.

DESIGN

National cohort study using data from the Australian and New Zealand Dialysis and Transplant Registry. We included all end-stage renal disease (ESRD) patients under 65 years of age who started treatment in Australia between January 1993 and December 1998. We used survival analysis to examine the time from commencement of renal replacement therapy (RRT) to transplantation. We measured time from commencement of RRT to acceptance onto the waiting list (stage 1), and time from acceptance onto the waiting list to transplantation (stage 2). The main outcome measures were (1) acceptance onto the waiting list and (2) receipt of a transplant, before 31 March 2000.

RESULTS

Indigenous patients had a lower transplantation rate (adjusted Indigenous: non-Indigenous rate ratio 0.32, 95% CI 0.25-0.40). They had both a lower rate of acceptance onto the waiting list (adjusted rate ratio 0.50, 95% CI 0.44-0.57) and a lower rate of moving from the list to transplantation (adjusted rate ratio 0.50, 95% CI 0.38-0.65). The disparities were not explained by differences in age, sex, co-morbidities or cause of renal disease.

CONCLUSIONS

Indigenous Australians face barriers to acceptance onto the waiting list and to moving from the list to transplantation. Further research to identify the causes could facilitate strategies to improve equity in transplantation.

A peritoneal dialysis patient with fatal culture-negative peritonitis. Case Discussion

Culture-negative peritoneal inflammation accounts for between 5 and 20% of cases of peritonitis in peritoneal dialysis patients. Diagnostic yields may be enhanced considerably by reculturing dialysate effluents using appropriate collection methods and optimal laboratory techniques (including prolonged low-temperature and anaerobic incubations). In patients with persistent culture-negative peritonitis, consideration should be given to the possibilities of unusual or fastidious microorganisms (especially fungi and mycobacteria) and non-infective causes (especially drug reactions, malignancy, visceral inflammation and retroperitoneal inflammation). In this paper, an illustrative case of persistent culture-negative peritonitis is presented followed by a discussion of the investigative approach to such patients, with particular emphasis on differential diagnosis and the limitations of currently available tests.

End-stage renal disease in indigenous Australians: a disease of disadvantage

OBJECTIVE

To determine the relation between area level indicators of socioeconomic disadvantage and the regional incidence of end-stage renal disease (ESRD) in indigenous Australians.

DESIGN

Ecological study.

SETTING

The 36 Aboriginal and Torres Strait Islander Commission regions of Australia.

MAIN OUTCOME MEASURES

The relation between area-based measures of disadvantage and the standardized incidence of ESRD for 36 Australian regions was examined using non-parametric tests of correlation.

RESULTS

Area-based measures of disadvantage showed a significant association with regional incidence of ESRD in indigenous Australians. (Early school leavers r = 0.68, P < .001, unemployment rate r = 0.72, P < .001, median household income r = -0.71, P < .001, number of persons per bedroom r = 0.84, P < .001, and low birthweight r = .49, P = .003). If it were possible to improve the health of all indigenous Australians to the level of that of the general Australian population, 87% of cases of ESRD could be avoided.

CONCLUSIONS

Socioeconomic factors appear to be strongly associated with rates of ESRD among indigenous Australians. Therefore, reducing the burden of renal disease in indigenous Australians is likely to require interventions addressing socioeconomic disadvantage in conjunction with biomedical interventions.

Delayed referral to a nephrologist: outcomes among patients who survive at least one year on dialysis

OBJECTIVE

To investigate whether late referral to a nephrologist of patients with chronic renal insufficiency influences the likelihood of both transplantation and mortality among those who survive at least one year on dialysis.

DESIGN

Retrospective national cohort study, using data from the Australia and New Zealand Dialysis and Transplant Registry database.

PARTICIPANTS

All patients with end-stage renal disease who started renal replacement treatment in Australia between 1 April 1995 and 31 December 1998, excluding those who received transplants or who died in their first year of dialysis. Patients referred "late" were defined as those who needed to commence dialysis within three months of referral to a nephrologist.

MAIN OUTCOME MEASURES

Length of patient survival, and whether patients received a transplant at any time between one year after starting dialysis and completion of the study on 31 March 2000.

RESULTS

Of the 4243 patients included in the study, 1141 (26.9%) were referred late. Late-referral (LR) patients were significantly less likely to receive a transplant in their second and subsequent years on dialysis (adjusted rate ratio, 0.78; 95% CI, 0.64-0.95). LR patients were at significantly increased risk of death after their first year on dialysis (adjusted hazard ratio, 1.19; 95% CI, 1.04-1.35).

CONCLUSIONS

Late referral is associated with increased mortality, even among those who survive their first year on dialysis. Improving the quality of pre-dialysis care might improve access to transplantation and long-term survival. General practitioners could minimise late referrals through targeted screening of high-risk individuals.

An epidemic of renal failure among Australian Aboriginals

OBJECTIVE

To define recent trends (1993-1996) in incidence of endstage renal disease (ESRD) among Australian Aboriginal people in the Top End of the Northern Territory (NT).

DESIGN

Analysis of hospital and clinical records of the Darwin-based ESRD treatment program from 1993 to 1996 and comparison with data accumulated since 1978.

PARTICIPANTS

All people entering the ESRD treatment program from 1978 to 1996.

MAIN OUTCOME MEASURES

Number of patients treated for ESRD; their ethnicity, age and sex; comorbidities in Aboriginal patients; treatment methods and outcomes.

RESULTS

More Aboriginal people presented with ESRD between 1993 and 1996 (87) than in the previous 15 years of the program (68). The incidence of ESRD in Aboriginals reached 838 per million in 1996, and is doubling every 4 years. Aboriginal people presenting with ESRD are younger than non-Aboriginal people with ESRD, and, in contrast to non-Aboriginals, ESRD rates are higher in women than men. The numbers and proportions of Aboriginal ESRD patients who have hypertension, type 2 diabetes and cardiac disease are rising. Haemodialysis remains the most common form of treatment, and the number of dialysis treatments is doubling every 2.5 years. Only 9% of Aboriginal patients entering the program in 1993-1996 were treated with chronic ambulatory peritoneal dialysis and only 3% received transplants. Despite their younger age, survival of Aboriginal people on dialysis is low (median 3.3 years v. 6.5 years in non-Aboriginals), and graft survival after transplant is poor (37% at 5 years v. 88% in non-Aboriginals). Survival has not improved in the past 4 years, with fewer deaths from infection offset by more deaths from cardiovascular disease.

CONCLUSIONS

The predicted doubling of ESRD incidence among Aboriginal people by the year 2000 will add an enormous burden to limited resources. Risk factors for renal disease underlie all the excess morbidity and mortality in NT Aboriginal adults, and arise out of accelerated lifestyle changes and socioeconomic disadvantage. Better living conditions and education, robust and integrated primary healthcare programs, and systematic screening for early renal disease and treatment of those with established disease are all matters of urgency.