Renal-related deaths in Australia 1997−1999

Analysis of Multiple Causes of Death: A Review of Methods and Practices

BACKGROUND

Research and reporting of mortality indicators typically focus on a single underlying cause of death selected from multiple causes recorded on a death certificate. The need to incorporate the multiple causes in mortality statistics-reflecting increasing multimorbidity and complex causation patterns-is recognized internationally. This review aims to identify and appraise relevant analytical methods and practices related to multiple causes.

METHODS

We searched Medline, PubMed, Scopus, and Web of Science from their incept ion to December 2020 without language restrictions, supplemented by consultation with international experts. Eligible articles analyzed multiple causes of death from death certificates. The process identified 4,080 items of which we reviewed 434 full-text articles.

RESULTS

Most articles we reviewed (76%, n = 332) were published since 2001. The majority of articles examined mortality by "any- mention" of the cause of death (87%, n = 377) and assessed pairwise combinations of causes (57%, n = 245). Since 2001, applications of methods emerged to group deaths based on common cause patterns using, for example, cluster analysis (2%, n = 9), and application of multiple-cause weights to re-evaluate mortality burden (1%, n = 5). We describe multiple-cause methods applied to specific research objectives for approaches emerging recently.

CONCLUSION

This review confirms rapidly increasing international interest in the analysis of multiple causes of death and provides the most comprehensive overview, to our knowledge, of methods and practices to date. Available multiple-cause methods are diverse but suit a range of research objectives. With greater availability of data and technology, these could be further developed and applied across a range of settings.

Decreasing rates of natural deaths in a remote Australian Aboriginal community, 1996-2010

OBJECTIVE

To examine the trends of all-cause natural mortality for people aged 15 years and over in a remote Australian Aboriginal community between 1996 and 2010.

METHODS

The annual population in the community by gender and age group was obtained from the Australian Bureau of Statistics (ABS). All known deaths and all records of start of renal replacement therapy (RRT) for renal failure were recorded between 1996 and 2010. Five-year aggregated death rates were calculated and the changes in natural mortality over the interval were evaluated. Mortality was compared with those of the Northern Territory (NT) Indigenous and non-Indigenous people as a whole from 1998 to 2006.

RESULTS

Rates of natural deaths were lower in the third interval 2006-2010 relative to the first interval 1996-2000, with higher, but more rapidly falling rates for females than males. Reductions were prominent for both sexes in the 65 and over age groups, but death rates in females of earlier middle age also trended lower. The trends applied whether or not the starting of RRT was considered as a natural death. There was a similar trend in rates of natural death in the aggregate Indigenous population of NT.

CONCLUSIONS

The downward trends probably reflect improvements in risk factor status since the 1960s, all-of-life health interventions, as well as better chronic disease management in the last two decades. The higher death rates in females than males in this community remain unexplained, but the rapid rate of decline of female death rates predicts that this gap will soon be minimised.

Pathways to palliative care for patients with chronic kidney disease

BACKGROUND

Despite the terminal nature of chronic kidney disease (CKD), end-of-life care planning is often inconsistent and pathways to palliative care are unclear. Health professionals' perceptions of palliative care and the prevailing context may influence their end-of-life decision making.

OBJECTIVES

To identify predictors of conservative treatment decisions and their associations with referral to palliative care, and to determine the perceptions that health professionals have about the role of palliative care in management of CKD.

METHODS

A retrospective audit of deceased patients' charts, spanning three years, and a survey of renal healthcare professionals, documenting CKD palliative care practices, knowledge and attitudes was carried out. Records of all patients with CKD dying between 1 January 2006 and 31 December 2008 in Australian regional renal service were audited. Renal staff from the service were surveyed. Logistic regression for binomial outcomes and ordinal logistic regression when more than two outcome levels were involved; and thematic analysis using a continual cross comparative approach was undertaken.

RESULTS

Loss of function, particularly from stroke, and severe pain are interpreted as representing levels of suffering which would justify the need to withdraw from renal replacement therapy. Family and/or patient indecision complicates and disrupts end-of-life care planning and can establish a cycle of ambiguity. Whilst renal healthcare professionals support early discussion of end-of-life care at predialysis education, congruity with the patient and family when making the final decision is of great importance.

CONCLUSION

Healthcare professionals' beliefs, values and knowledge of palliative care influence their end-of-life care decisions. The influence of patient, family and clinicians involves negotiation and equivocation. Health professionals support the early discussion of end-of-life care in CKD at predialysis education to enable clearer decision making.

Blood pressure is a major risk factor for renal death: an analysis of 560 352 participants from the Asia-Pacific region

Chronic kidney disease is a major worldwide public health problem that causes substantial morbidity and mortality. Studies from the Asia-Pacific region have reported some of the highest chronic kidney disease prevalence rates in the world, but access to dialysis is limited in many countries, making it imperative to identify high-risk individuals. We performed a participant-level data overview of prospective studies conducted in the Asia-Pacific region to quantify the magnitude and direction of the associations between putative risk factors and renal death. Age- and sex-adjusted Cox proportional hazards models were applied to pooled data from 35 studies to calculate hazard ratios (95% CIs) for renal death associated with a standardized change in risk factors. Among 560 352 participants followed for a median of 6.8 years, a total of 420 renal deaths were observed. Continuous and positive associations among systolic blood pressure, diastolic blood pressure, fasting blood glucose, and total cholesterol levels with renal death were observed, as well as a continuous but inverse association with high-density lipoprotein cholesterol. Systolic blood pressure was the strongest risk factor for renal death with each SD increase in systolic blood pressure (19 mm Hg) associated with >80% higher risk (hazard ratio: 1.84; 95% CI: 1.60 to 2.12). Neither cigarette smoking nor excess weight was related to the risk of renal death (P>0.10). The results were similar for cohorts in Asia and Australia. These results suggest that primary prevention strategies for renal disease should focus on individuals with elevated blood pressure, diabetes mellitus, and dyslipidemia.

Renal-related deaths in Indigenous people in Queensland, Australia

AIM

Indigenous Australians have much higher mortality than non-Indigenous Australians. We aimed to quantify the excess of deaths with a renal causal assignment among Indigenous people aged 25 years and over in Queensland, Australia, 1997-2000 and their distribution by remoteness.

METHODS

Both underlying and associated causes defined by ICD, 10(th) edition, were examined. Mortality rates were standardized to the concurrent non-Indigenous population.

RESULTS

In Indigenous people, standardized mortality ratios with a renal assignment of death by remoteness of residence were 194% (Major City and Inner Regional), 439% (Outer Regional and Remote) and 782% (Very Remote). Of all these deaths with a renal assignment, only 18% had a renal assignment as the underlying cause. Diabetes and cardiovascular disease were frequent concomitant causes in deaths with a renal assignment.

CONCLUSION

The Indigenous population in Queensland has elevated rates of renal deaths compared with the non-Indigenous population. This disparity increases markedly with increasing remoteness of residence. Reliance on underlying causes of death alone greatly underestimates the association of renal disease with deaths in this population.

Lessons in ethnonephrology

Only recently has the nephrology community moved beyond a fairly singular focus on terminal kidney failure to embrace population-based studies of earlier stages of disease, its markers and risk factors, and of interventions. Observations in developing countries, and in minority, migrant, and disadvantaged groups in westernized countries, have promoted these developments. We are only beginning to interpret renal disease in the context of public health history, social and health transitions, changing population demography, and competing mortality. Its intimate relationships to other health issues are being progressively exposed. Perspectives on the multideterminant etiology of most disease and the pedestrian nature of most risk factors are maturing. We are challenged to reconcile epidemiologic patterns with morphology in diseased renal tissue, and to consider structural markers, such as nephron number and glomerular size, as determinants of disease susceptibility. New work force models are mandated for population-based studies and intervention programs. Intervention programs need to be integrated with other chronic disease initiatives and nested in a matrix of systematic primary care, and although flexible to changing needs, must be sustained over the long term. Cross-disciplinary collaboration is essential in designing those programs, and in promoting them to health-care funders. Substantial expansion and restructuring of the discipline is needed for the nephrology community to participate effectively in those processes.

Chronic kidney disease in the general population

End-stage kidney disease (ESKD), defined as the need for dialysis, receipt of a transplant, or death from chronic kidney failure, generally affects fewer than 1% of the population. However ESKD is the end result of chronic kidney disease (CKD), a widely prevalent but often silent condition with elevated risks of cardiovascular morbidity and mortality and a range of metabolic complications. A recently devised classification of CKD has facilitated prevalence estimates that reveal an "iceberg" of CKD in the community, of which dialysis and transplant patients are the tip. Hypertension, smoking, hypercholesterolemia, and obesity, currently among the World Health Organization's (WHO's) top 10 global health risks, are strongly associated with CKD. The factors, together with increasing diabetes prevalence and an aging population, will result in significant global increases in CKD and ESKD patients. Treatments now available effectively reduce the rate of progression of CKD and the extent of comorbid conditions and complications. The challenges are (1) to intervene effectively to reduce the excess burden of cardiovascular morbidity and mortality associated with CKD, (2) to identify those at greatest risk for ESKD and intervene effectively to prevent progression of early CKD, and (3) to ultimately introduce cost-effective primary prevention to reduce the overall burden of CKD. The vast majority of the global CKD burden will be in developing countries, and policy responses must be both practical and sustainable in these settings.

The influence of obesity on the development and survival outcomes of chronic kidney disease

The prevalence of obesity, defined as a body mass index (BMI) greater than 30 kg/m2 , has more than doubled in many Western countries over the past 2 decades and has become a major public health challenge. This epidemic of obesity in developed countries has been matched closely by alarming increases in the incidence of diabetes mellitus, hypertension, chronic kidney disease (CKD), and cardiovascular disease. However, the exact role that increased body size plays in the development of nephropathy and its subsequent contribution to cardiovascular morbidity and mortality remain unclear. For example, whether obesity per se is a risk factor for CKD independent of diabetes mellitus and hypertension is uncertain. Moreover, in patients with end-stage kidney disease, strong evidence suggests that obesity may paradoxically enhance patient survival. This review will focus on the evidence for obesity as an independent risk factor for the development and progression of CKD and as a paradoxical survival factor in patients with end-stage kidney failure. Possible mechanisms underlying these observed associations will be discussed.