Treatment decision-making and care among older adults with kidney failure: protocol for a multicentre, prospective observational cohort study with nested substudies and linked qualitative research (the Elderly Advanced CKD Programme)

INTRODUCTION

Shared treatment decision-making and planning of care are fundamental in advanced chronic kidney disease (CKD) management. There are limited data on several key outcomes for the elderly population including survival, quality of life, symptom burden, changes in physical functioning and experienced burden of healthcare. Patients, caregivers and clinicians consequently face significant uncertainty when making life-impacting treatment decisions. The Elderly Advanced CKD Programme includes quantitative and qualitative studies to better address challenges in treatment decision-making and planning of care among this increasingly prevalent elderly cohort.

METHODS AND ANALYSIS

The primary component is OUTcomes of Older patients with Kidney failure (OUTLOOK), a multicentre prospective observational cohort study that will enrol 800 patients ≥75 years with kidney failure (estimated glomerular filtration rate ≤15 mL/min/1.73 m²) across a minimum of six sites in Australia. Patients entered are in the decision-making phase or have recently made a decision on preferred treatment (dialysis, conservative kidney management or undecided). Patients will be prospectively followed until death or a maximum of 4 years, with the primary outcome being survival. Secondary outcomes are receipt of short-term acute dialysis, receipt of long-term maintenance dialysis, changes in biochemistry and end-of-life care characteristics. Data will be used to formulate a risk prediction tool applicable for use in the decision-making phase. The nested substudies Treatment modalities for the InfirM ElderLY with end stage kidney disease (TIMELY) and Caregivers of The InfirM ElderLY with end stage kidney disease (Co-TIMELY) will longitudinally assess quality of life, symptom burden and caregiver burden among 150 patients and 100 caregivers, respectively. CONsumer views of Treatment options for Elderly patieNts with kiDney failure (CONTEND) is an additional qualitative study that will enrol a minimum of 20 patients and 20 caregivers to explore experiences of treatment decision-making and care.

ETHICS AND DISSEMINATION

Ethics approval was obtained through Sydney Local Health District Human Research Ethics Committee (2019/ETH07718, 2020/ETH02226, 2021/ETH01020, 2019/ETH07783). OUTLOOK is approved to have waiver of individual patient consent. TIMELY, Co-TIMELY and CONTEND participants will provide written informed consent. Final results will be disseminated through peer-reviewed journals and presented at scientific meetings.

Prevalence, incidence and risk factors of diabetes in Australian adults aged ≥45 years: A cohort study using linked routinely-collected data

Aims

To use linked routinely-collected health data to estimate diabetes prevalence and incidence in an Australian cohort of adults aged ≥45 years, and examine risk factors associated with incident disease.

Research design and methods

The EXamining ouTcomEs in chroNic Disease in the 45 and Up Study (EXTEND45) Study is a linked data study that combines baseline questionnaire responses from the population-based 45 and Up Study (2006–2009, n = 267,153) with multiple routinely-collected health databases up to December 2014. Among participants with ≥1 linked result for any laboratory test, diabetes status was determined from multiple data sources according to standard biochemical criteria, use of glucose-lowering medication or self-report, and the prevalence and incidence rate calculated. Independent risk factors of incident diabetes were examined using multivariable Cox regression.

Results

Among 152,169 45 and Up Study participants with ≥1 linked laboratory result in the EXTEND45 database (mean age 63.0 years; 54.9% female), diabetes prevalence was 10.8% (95% confidence interval [CI] 10.6%–10.9%). Incident disease in those without diabetes at baseline (n = 135,810; mean age 62.5 years; 56.1% female) was 10.0 per 1,000 person-years (95% CI 9.8–10.2). In all age groups, diabetes incidence was lower in women compared to men, an association that persisted in the fully adjusted analyses. Other independent risk factors of diabetes were older age, being born outside of Australia (with the highest rate of 19.2 per 1,000 person-years observed in people born in South and Central Asia), lower education status, lower annual household income, residence in a major city, family history of diabetes, personal history of cardiovascular disease or hypertension, higher body mass index, smoking and long sleeping hours.

Conclusions

Our study represents an efficient approach to assessing diabetes frequency and its risk factors in the community. The infrastructure provided by the EXTEND45 Study will be useful for diabetes surveillance and examining other important clinical and epidemiological questions.

Risk Factors for Incident Kidney Disease in Older Adults: an Australian Prospective Population-Based Study

BACKGROUND

We aimed to determine risk factors for incident CKD in a large population-based cohort.

METHODS

This prospective opt-in population-based cohort study is based on the 45 and Up Study, where New South Wales residents aged ≥45 years were randomly sampled from the Services Australia enrolment database and agreed to complete the 45 and Up Study baseline questionnaire and have their responses linked to their health data in routinely-collected databases. The primary outcome was the development of incident CKD, defined as eGFR<60ml/min/1.73m² . CKD incidence was calculated using Poisson regression. Risk factors for incident CKD were assessed using Cox regression in multivariable models.

RESULTS

In 39,574 participants who did not have CKD at enrolment, independent factors associated with developing CKD included: older age, regional residence (HR 1.38 [1.27-1.50] for outer regional versus major city), smoking (1.13 [1.00-1.27] for current smoker versus non-smoker), obesity (1.25 [1.16-1.35] for obese versus normal body mass index), diabetes mellitus (1.41 [1.33-1.50]), hypertension (1.53 [1.44-1.62]), coronary heart disease (1.13 [1.07-1.20]), depression/anxiety (1.16 [1.09-1.24]), and cancer (1.29 [1.20-1.39]). Migrants were less likely to develop CKD compared with people born in Australia (0.88 [0.83-0.94]). Gender, partner status and socioeconomic factors were not independently associated with developing CKD.

CONCLUSIONS

This large population-based study found multiple modifiable and non-modifiable factors were independently associated with developing CKD. In the Australian setting, the risk of CKD was higher with regional residence. Differences according to socioeconomic status were predominantly explained by age, comorbidities and harmful health-related behaviours This article is protected by copyright. All rights reserved.

Incidence and Associations of Chronic Kidney Disease in Community Participants With Diabetes: A 5-Year Prospective Analysis of the EXTEND45 Study

OBJECTIVE

To determine the incidence of and factors associated with an estimated glomerular filtration rate (eGFR) <60 mL/min/1.73 m² in people with diabetes.

RESEARCH DESIGN AND METHODS

We identified people with diabetes in the EXamining ouTcomEs in chroNic Disease in the 45 and Up Study (EXTEND45), a population-based cohort study (2006-2014) that linked the Sax Institute's 45 and Up Study cohort to community laboratory and administrative data in New South Wales, Australia. The study outcome was the first eGFR measurement <60 mL/min/1.73 m² recorded during the follow-up period. Participants with eGFR < 60 mL/min/1.73 m² at baseline were excluded. We used Poisson regression to estimate the incidence of eGFR <60 mL/min/1.73 m² and multivariable Cox regression to examine factors associated with the study outcome.

RESULTS

Of 9,313 participants with diabetes, 2,106 (22.6%) developed incident eGFR <60 mL/min/1.73 m² over a median follow-up time of 5.7 years (interquartile range, 3.0-5.9 years). The eGFR <60 mL/min/1.73 m² incidence rate per 100 person-years was 6.0 (95% CI 5.7-6.3) overall, 1.5 (1.3-1.9) in participants aged 45-54 years, 3.7 (3.4-4.0) for 55-64 year olds, 7.6 (7.1-8.1) for 65-74 year olds, 15.0 (13.0-16.0) for 75-84 year olds, and 26.0 (22.0-32.0) for those aged 85 years and over. In a fully adjusted multivariable model incidence was independently associated with age (hazard ratio 1.23 per 5-year increase; 95% CI 1.19-1.26), geography (outer regional and remote versus major city: 1.36; 1.17-1.58), obesity (obese class III versus normal: 1.44; 1.16-1.80), and the presence of hypertension (1.52; 1.33-1.73), coronary heart disease (1.13; 1.02-1.24), cancer (1.30; 1.14-1.50), and depression/anxiety (1.14; 1.01-1.27).

CONCLUSIONS

In participants with diabetes, the incidence of an eGFR <60 mL/min/1.73 m² was high. Older age, remoteness of residence, and the presence of various comorbid conditions were associated with higher incidence.

EXamining ouTcomEs in chroNic Disease in the 45 and Up Study (the EXTEND45 Study): Protocol for an Australian Linked Cohort Study

Background

Chronic kidney disease (CKD) and diabetes are the major causes of death and disability worldwide. They are associated with high health service utilization persisting over many years. Their slow progression and wide clinical variation make them eminently suitable for study in population-based cohorts. However, current understanding of their prevalence, incidence, and progression is largely based on studies conducted in clinical populations.

Objective

This study aims to establish a novel link between an existing population-based cohort (the 45 and Up Study) and routinely collected laboratory and administrative data to facilitate research across the full disease spectrum of CKD and diabetes.

Methods

In the EXTEND45 Study (EXamining OuTcomEs in chroNic Disease in the 45 and Up Study), baseline questionnaire responses of over 260,000 participants of the 45 and Up Study aged ≥45 years living in New South Wales (NSW), collected between January 2006 and December 2009, are linked to data from laboratory service providers as well as national- and state-based administrative datasets via probabilistic linkage. Routinely collected data were obtained for participants who could be linked between January 2005 and July 2013. Laboratory data will enable the identification of early cases of chronic disease and the assessment of clinically relevant biochemical targets during the disease course. Health administrative datasets will allow for the examination of health service use, pharmacological management, and clinical outcomes.

Results

The study received ethics approval from the NSW Population and Health Services Research Ethics Committee in February 2014. Data linkage for 267,153 of the 45 and Up Study participants was completed in June 2016, with congruent linkage achieved for 265,086 (99.23%) individuals. To date, the CKD and diabetes cohorts have been identified (published elsewhere), and a diverse portfolio of research projects relating to disease burden, risk factors, health outcomes, and health service utilization is in development.

Conclusions

The EXTEND45 Study represents an unparalleled opportunity to perform extensive research into diseases of considerable public health and clinical importance. Strengths include the population-based nature of the cohort and the availability of longitudinal information on the complete disease pathway for affected individuals.

International Registered Report Identifier (IRRID)

RR1-10.2196/15646

Burden of Care and Quality of Life Among Caregivers for Adults Receiving Maintenance Dialysis: A Systematic Review

RATIONALE & OBJECTIVE

Dialysis is a burdensome and complex treatment for which many recipients require support from caregivers. The impact of caring for people dependent on dialysis on the quality of life of the caregivers has been incompletely characterized.

STUDY DESIGN

Systematic review of quantitative studies of quality of life and burden to caregivers.

SETTING & STUDY POPULATION

Caregivers of adults receiving maintenance dialysis.

SELECTION CRITERIA FOR STUDIES

The Cochrane Library, Embase, PsycINFO, CINAHL, PubMed, and MEDLINE were systematically searched from inception until December 2016 for quantitative studies of caregivers. Pediatric and non-English language studies were excluded. Study quality was assessed using a modified Newcastle-Ottawa scale.

DATA EXTRACTION

2 independent reviewers selected studies and extracted data using a prespecified extraction instrument.

ANALYTICAL APPROACH

Descriptive reports of demographics, measurement scales, and outcomes. Quantitative meta-analysis using random effects when possible.

RESULTS

61 studies were identified that included 5,367 caregivers from 21 countries and assessed the impact on caregivers using 70 different scales. Most (85%) studies were cross-sectional. The largest identified group of caregivers was female spouses who cared for recipients of facility-based hemodialysis (72.3%) or peritoneal dialysis (20.6%). Caregiver quality of life was poorer than in the general population, mostly comparable with caregivers of people with other chronic diseases, and often better than experienced by the dialysis patients cared for. Caregiver quality of life was comparable across dialysis modalities.

LIMITATIONS

Heterogeneity in study design and outcome measures made comparisons between studies difficult and precluded quantitative meta-analysis. Study quality was generally poor.

CONCLUSIONS

Quality of life of caregivers of dialysis recipients is poorer than in the general population and comparable to that of caregivers of individuals with other chronic diseases. The impact of caring for recipients of home hemodialysis or changes in the impact of caring over time have not been well studied. Further research is needed to optimally inform dialysis programs how to educate and support caregivers.

Retrospective chart review to assess domains of quality of death (recognition of dying, appropriate limitations, symptom monitoring, anticipatory prescribing) of patients dying in the acute hospital under the care of a nephrology service with renal supportive care support over time

AIM

To explore the quality of deaths in an acute hospital under a nephrology service at two teaching hospitals in Sydney with renal supportive care services over time.

METHODS

Retrospective chart review of all deaths in the years 2004, 2009 and 2014 at St George Hospital (SGH) and in 2014 at the Concord Repatriation General Hospital. Domains assessed were recognition of dying, invasive interventions, symptom assessment, anticipatory prescribing, documentation of spiritual needs and bereavement information for families. End-of-life care plan (EOLCP) use was also evaluated at SGH.

RESULTS

Over 90% of patients were recognized to be dying in all 3 years at SGH. Rates of interventions in the last week of life were low and did not differ across the 3 years. There was a significant increase in the prescription of anti-psychotic, anti-emetic and anti-cholinergic medication over the years at SGH. Use of EOLCP was significantly higher at SGH, and their use improved several quality domains. Of all deaths, 68% were referred to palliative care at SGH and 33% at Concord Repatriation General Hospital (not significant). Cessation of observations and non-essential medications and documentation of bereavement information given to families was low across both sites in all years, although this significantly improved when EOLCP were used.

CONCLUSION

While acute teams are good at recognizing dying, they need support to care for dying patients. The use of EOLCP in acute services can facilitate improvements in caring for the dying. Renal supportive care services need time to become embedded in the culture of the acute hospital.

Effects of sodium-glucose cotransporter-2 inhibitors on cardiovascular disease, death and safety outcomes in type 2 diabetes - A systematic review

AIM

Sodium glucose co-transporter 2 (SGLT2) inhibitors appear to protect against increased risks of cardiovascular and kidney disease in patients with type 2 diabetes but also cause some harms. Whether effects are comparable across drug class or specific to individual compounds is unclear. This meta-analysis assessed the class and individual compound effects of SGLT2 inhibition versus control on cardiovascular events, death, kidney disease and safety outcomes in patients with type 2 diabetes.

METHODS

MEDLINE, EMBASE, the Cochrane Library and regulatory databases were systematically searched for data from randomized clinical trials that included reporting of cardiovascular events, deaths or safety outcomes. We used fixed effects models and inverse variance weighting to calculate relative risks with the 95% confidence intervals.

RESULTS

The analyses included data from 82 trials, four overviews and six regulatory reports and there were 1,968 major cardiovascular events identified for analysis. Patients randomly assigned to SGLT2 had lower risks of major cardiovascular events (RR 0.85, 95%CI 0.77-0.93), heart failure (RR 0.67, 95%CI 0.55-0.80), all-cause death (RR 0.79, 95%CI 0.70-0.88) and serious decline in kidney function (RR 0.59, 0.49-0.71). Significant adverse effects were observed for genital infections (RR 3.06, 95%CI 2.73-4.43), volume depletion events (RR 1.24, 95%CI 1.07-1.43) and amputation (RR 1.44 95%CI 1.13-1.83). There was a high likelihood of differences in the associations of the individual compounds with cardiovascular death, hypoglycaemia and amputation (all I² > 80%) and a moderate likelihood of differences in the associations with non-fatal stroke, all-cause death, urinary tract infection and fracture (all I² > 30%).

CONCLUSION

There are strong overall associations of SGLT2 inhibition with protection against major cardiovascular events, heart failure, serious decline in kidney function and all-cause death. SGLT2 inhibitors were also associated with infections, volume depletion effects and amputation. Some associations appear to differ between compounds.

Effects of sodium-glucose cotransporter-2 inhibitors on cardiovascular events, death, and major safety outcomes in adults with type 2 diabetes: a systematic review and meta-analysis

BACKGROUND

In patients with type 2 diabetes, sodium-glucose cotransporter-2 (SGLT2) inhibitors are known to reduce glucose concentrations, blood pressure, and weight, but to increase LDL cholesterol and the incidence of urogenital infections. Protection against cardiovascular events has also been reported, as have possible increased risks of adverse outcomes such as ketoacidosis and bone fracture. We aimed to establish the effects of SGLT2 inhibitors on cardiovascular events, death, and safety outcomes in adults with type 2 diabetes, both overall and separately for individual drugs.

METHODS

In this systematic review and meta-analysis, we searched MEDLINE, Embase, the Cochrane Library, and websites of US, European, and Japanese regulatory authorities from Jan 1, 1950, to Sept 30, 2015, for data from prospective randomised controlled trials assessing the effects of SGLT2 treatment compared with controls. We excluded duplicate reports, trials of compound drugs, trials that lasted 7 days or fewer, trials that did not report on outcomes of interest, and articles that presented pooled trial data for which the individual trials could not be identified. We extracted data in duplicate using a standardised approach. The primary outcome was major adverse cardiovascular events. Secondary outcomes were cardiovascular death, non-fatal myocardial infarction, non-fatal stroke, admission to hospital for unstable angina, heart failure, and all-cause mortality. We estimated summary relative risks with fixed-effects meta-analysis, with the I(2) statistic used to estimate heterogeneity of results beyond chance.

FINDINGS

The analyses included data from six regulatory submissions (37 525 participants) and 57 published trials (33 385 participants), which provided data for seven different SGLT2 inhibitors. SGLT2 inhibitors protected against the risk of major adverse cardiovascular events (relative risk 0·84 [95% CI 0·75-0·95]; p=0·006), cardiovascular death (0·63 [0·51-0·77]; p<0·0001), heart failure (0·65 [0·50-0·85]; p=0·002), and death from any cause (0·71 [0·61-0·83]; p<0·0001). No clear effect was apparent for non-fatal myocardial infarction (0·88 [0·72-1·07]; p=0·18) or angina (0·95 [0·73-1·23]; p=0·70), but we noted an adverse effect for non-fatal stroke (1·30 [1·00-1·68]; p=0·049). We noted no clear evidence that the individual drugs had different effects on cardiovascular outcomes or death (all I(2)<43%). Safety analyses showed consistent increased risks of genital infections (regulatory submissions 4·75 [4·00-5·63]; scientific reports 2·88 [2·48-3·34]), but findings for some safety outcomes varied depending on whether anlayses were based on data extracted from regulatory submissions or trials reported in the scientific literature.

INTERPRETATION

These data suggest net protection of SGLT2 inhibitors against cardiovascular outcomes and death. The efficacy results were driven by findings for empagliflozin (the only SGLT2 inhibitor for which data from a dedicated long-term cardiovascular safety trial have been reported), although results for the other drugs in the class were not clearly different. Adverse events were more difficult to quantify than was efficacy, with the effects of individual drugs in the class seeming to differ for some safety outcomes. Results from ongoing studies will be crucial to substantiate these findings across the drug class, but the available data provide a strong rationale to expect benefit from use of SGLT2 inhibitors in patients with type 2 diabetes at high risk of cardiovascular events.

FUNDING

National Health and Medical Research Council of Australia.

CKD in elderly patients managed without dialysis: survival, symptoms, and quality of life

BACKGROUND AND OBJECTIVES

Survival, symptom burden, and quality of life (QOL) are uncertain for elderly patients with advanced CKD managed without dialysis. We examined these outcomes in patients managed with renal supportive care without dialysis (RSC-NFD) and those planned for or commencing dialysis.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

In this prospective observational study, symptoms were measured using the Memorial Symptom Assessment Scale and the Palliative care Outcomes Scale - Symptoms (renal) inventory and QOL was measured using the Short Form-36 survey. This study comprised 273 predialysis patients who had usual nephrology care and 122 nondialysis pathway patients who also attended a renal supportive care clinic adding the skills of a palliative medicine team. A further 72 patients commenced dialysis during this period without attending either clinic.

RESULTS

Nondialysis patients were older than the predialysis group (82 versus 67 years; P<0.001) but had similar eGFR at the first clinic visit (16 ml/min per 1.73 m(2); P=0.92). Of the predialysis patients, 92 (34%) commenced dialysis. Compared with the RSC-NFD group, the death rate was lower in the predialysis group who did not require dialysis (hazard ratio, 0.23; 95% confidence interval, 0.12 to 0.41] and in those requiring dialysis (0.30; 0.13 to 0.67) but not in dialysis patients who had not attended the predialysis clinic (0.60; 0.35 to 1.03). Median survival in RSC-NFD patients was 16 (interquartile range, 9, 37) months and 32% survived >12 months after eGFR fell below 10 ml/min per 1.73 m(2). For the whole group, age, serum albumin, and eGFR <15 ml/min per 1.73 m(2) were associated with poorer survival. Of the nondialysis patients, 57% had stable or improved symptoms over 12 months and 58% had stable or improved QOL.

CONCLUSIONS

Elderly patients who choose not to have dialysis as part of shared decision making survive a median of 16 months and about one-third survive 12 months past a time when dialysis might have otherwise been indicated. Utilizing the skills of palliative medicine helps provide reasonable symptom control and QOL without dialysis.

COnsiderations of Nephrologists when SuggestIng Dialysis in Elderly patients with Renal failure (CONSIDER): a discrete choice experiment

BACKGROUND

Nephrologists often face difficult decisions when recommending dialysis or non-dialysis (supportive) care for elderly patients, given the uncertainty around survival and the burden of dialysis. Discrete choice experiments (DCEs) mimic real-world decisions through simultaneous consideration of multiple variables. We aimed to determine the relative influence of patient characteristics on dialysis recommendations.

METHODS

We conducted a DCE among Australasian nephrologists consisting of 12 scenarios of two patients (described in terms of age, gender, cognition, comorbidity, life expectancy, current quality of life (QOL), expected QOL with dialysis, social support, patient and family inclination). Nephrologists indicated which patient they preferred recommending dialysis for, or whether they preferred 'neither'. Mixed logit models determined the odds of recommending dialysis over no dialysis. Trade-offs between QOL and survival were calculated.

RESULTS

A total of 159 nephrologists participated (34% aged 40-49 years, 62% male and 69% Caucasian). All patient characteristics except gender significantly affected the likelihood of dialysis recommendation. Nephrologists were more likely to recommend dialysis for patients with preserved cognition (odds ratio [OR]: 68.3; 95% confidence interval [CI]: 33.4-140.0), lower comorbidity (OR: 2.1; 95% CI: 1.1-4.1), increased life expectancy (OR: 2.8; 95% CI: 2.1-3.7), high current QOL (OR: 2.8; 95% CI: 2.0-3.8) and positive patient and family dialysis inclination (OR: 27.5; 95% CI: 16.2-46.8 and OR: 2.0; 95% CI: 1.3-3.3, respectively). Nephrologists aged >65 were more likely (OR: 11.7; 95% CI: 1.8-77.2) to recommend dialysis. Nephrologists were willing to forgo 12 months of patient survival to avoid substantial QOL decrease with dialysis.

CONCLUSION

Nephrologists avoided dialysis recommendation if it was expected to considerably reduce QOL. To inform elderly patients' dialysis decisions, systematic and longitudinal cognition and QOL evaluations are needed as well as better research into understanding patient preferences.

Effects of intensive blood pressure lowering on the progression of chronic kidney disease: a systematic review and meta-analysis

BACKGROUND

Recent guidelines suggest lowering the target blood pressure for patients with chronic kidney disease, although the strength of evidence for this suggestion has been uncertain. We sought to assess the renal and cardiovascular effects of intensive blood pressure lowering in people with chronic kidney disease.

METHODS

We performed a systematic review and meta-analysis of all relevant reports published between 1950 and July 2011 identified in a search of MEDLINE, Embase and the Cochrane Library. We included randomized trials that assigned patients with chronic kidney disease to different target blood pressure levels and reported kidney failure or cardiovascular events. Two reviewers independently identified relevant articles and extracted data.

RESULTS

We identified 11 trials providing information on 9287 patients with chronic kidney disease and 1264 kidney failure events (defined as either a composite of doubling of serum creatinine level and 50% decline in glomerular filtration rate, or end-stage kidney disease). Compared with standard regimens, a more intensive blood pressure-lowering strategy reduced the risk of the composite outcome (hazard ratio [HR] 0.82, 95% confidence interval [CI] 0.68-0.98) and end-stage kidney disease (HR 0.79, 95% CI 0.67-0.93). Subgroup analysis showed effect modification by baseline proteinuria (p = 0.006) and markers of trial quality. Intensive blood pressure lowering reduced the risk of kidney failure (HR 0.73, 95% CI 0.62-0.86), but not in patients without proteinuria at baseline (HR 1.12, 95% CI 0.67-1.87). There was no clear effect on the risk of cardiovascular events or death.

INTERPRETATION

Intensive blood pressure lowering appears to provide protection against kidney failure events in patients with chronic kidney disease, particularly among those with proteinuria. More data are required to determine the effects of such a strategy among patients without proteinuria.

Perspective - the issues surrounding ESKD and dialysis in the elderly and those with co-morbidities

There is a disproportionate increase in the number of elderly patients, many with multiple co-morbidities, commencing dialysis. Predictors of survival for elderly patients on dialysis include age, comorbidity score, malnutrition, poor functional status and late referral. Patients with high co morbidity scores may not gain a survival advantage with dialysis vs a non dialysis pathway. Late referral and lack of dialysis access are independent predictors of mortality in elderly patients commencing dialysis. Hospital free survival may be similar in dialysis and non-dialysis treated groups We have little data on those choosing not to start dialysis in terms of numbers, clinical course and survival. Most available data is not from an Australian or New Zealand source. The effects on quality of life of different management pathways on patients, carers and staff still need to be addressed.

Effects of SGLT2 inhibitors on cardiovascular outcomes

Glucose in the glomerular ultrafiltrate is actively reabsorbed by sodium glucose transporters (SGLT) in the proximal tubule. The SGLT2 protein is a high capacity molecule responsible for the majority of glucose reuptake with pharmacological inhibition, resulting in the loss of about 80g of glucose in the urine each day. About a dozen inhibitors of SGLT2 have entered clinical development, and the first has recently been submitted for registration with the United States Food and Drug Administration. The rationale for the clinical evaluation of these agents is their beneficial effects on glycaemia, blood pressure and body weight. No adequately powered trial has yet determined the effects of an SGLT2 inhibitor on either macrovascular or microvascular outcomes, although a number of large-scale trials are now ongoing. Evidence that will define the overall balance of benefits and risks of this new drug class is anticipated within the next 5 years.

Effects of fibrates on cardiovascular outcomes: a systematic review and meta-analysis

BACKGROUND

Several clinical trials have reported inconsistent findings for the effect of fibrates on cardiovascular risk. We undertook a systematic review and meta-analysis to investigate the effects of fibrates on major clinical outcomes.

METHODS

We systematically searched Medline, Embase, and the Cochrane Library for trials published between 1950 and March, 2010. We included prospective randomised controlled trials assessing the effects of fibrates on cardiovascular outcomes compared with placebo. Summary estimates of relative risk (RR) reductions were calculated with a random effects model. Outcomes analysed were major cardiovascular events, coronary events, stroke, heart failure, coronary revascularisation, all-cause mortality, cardiovascular death, non-vascular death, sudden death, new onset albuminuria, and drug-related adverse events.

FINDINGS

We identified 18 trials providing data for 45 058 participants, including 2870 major cardiovascular events, 4552 coronary events, and 3880 deaths. Fibrate therapy produced a 10% RR reduction (95% CI 0-18) for major cardiovascular events (p=0.048) and a 13% RR reduction (7-19) for coronary events (p<0.0001), but had no benefit on stroke (-3%, -16 to 9; p=0.69). We noted no effect of fibrate therapy on the risk of all-cause mortality (0%, -8 to 7; p=0.92), cardiovascular mortality (3%, -7 to 12; p=0.59), sudden death (11%, -6 to 26; p=0.19), or non-vascular mortality (-10%, -21 to 0.5; p=0.063). Fibrates reduced the risk of albuminuria progression by 14% (2-25; p=0.028). Serious drug-related adverse events were not significantly increased by fibrates (17 413 participants, 225 events; RR 1.21, 0.91-1.61; p=0.19), although increases in serum creatinine concentrations were common (1.99, 1.46-2.70; p<0.0001).

INTERPRETATION

Fibrates can reduce the risk of major cardiovascular events predominantly by prevention of coronary events, and might have a role in individuals at high risk of cardiovascular events and in those with combined dyslipidaemia.

FUNDING

National Health and Medical Research Council of Australia.

Report of the equine herpesvirus-1 Havermeyer Workshop, San Gimignano, Tuscany, June 2004

Amongst the infectious diseases that threaten equine health, herpesviral infections remain a world wide cause of serious morbidity and mortality. Equine herpesvirus-1 infection is the most important pathogen, causing an array of disorders including epidemic respiratory disease abortion, neonatal foal death, myeloencephalopathy and chorioretinopathy. Despite intense scientific investigation, extensive use of vaccination, and established codes of practice for control of disease outbreaks, infection and disease remain common. While equine herpesvirus-1 infection remains a daunting challenge for immunoprophylaxis, many critical advances in equine immunology have resulted in studies of this virus, particularly related to MHC-restricted cytotoxicity in the horse. A workshop was convened in San Gimignano, Tuscany, Italy in June 2004, to bring together clinical and basic researchers in the field of equine herpesvirus-1 study to discuss the latest advances and future prospects for improving our understanding of these diseases, and equine immunity to herpesviral infection. This report highlights the new information that was the focus of this workshop, and is intended to summarize this material and identify the critical questions in the field.

Sphingosine-1-phosphate lyase has a central role in the development of Dictyostelium discoideum

Sphingosine-1-phosphate, a product of sphingomyelin degradation, is an important element of signal transduction pathways that regulate cell proliferation and cell death. We have demonstrated additional roles for sphingosine-1-phosphate in growth and multicellular development. The specific disruption in Dictyostelium discoideum of the sphingosine-1-phosphate lyase gene, which encodes the enzyme that catalyzes sphingosine-1-phosphate degradation, results in a mutant strain with aberrant morphogenesis, as well as an increase in viability during stationary phase. The absence of sphingosine-1-phosphate lyase affects multiple stages throughout development, including the cytoskeletal architecture of aggregating cells, the ability to form migrating slugs, and the control of cell type-specific gene expression and terminal spore differentiation. This pleiotropic effect, which is due to the loss of sphingosine-1-phosphate lyase, establishes sphingolipids as pivotal regulatory molecules in a wide range of processes in multicellular development.

Differential developmental expression and cell type specificity of Dictyostelium catalases and their response to oxidative stress and UV-light

Cells of Dictyostelium discoideum are highly resistant to DNA damaging agents such as UV-light, gamma-radiation and chemicals. The genes encoding nucleotide excision repair (NER) and base excision repair (BER) enzymes are rapidly upregulated in response to UV-irradiation and DNA-damaging chemicals, suggesting that this is at least partially responsible for the resistance of this organism to these agents. Although Dictyostelium is also unusually resistant to high concentrations of H(2)O(2), little is known about the response of this organism to oxidative stress. To determine if transcriptional upregulation is a common mechanism for responding to DNA-damaging agents, we have studied the Dictyostelium catalase and Cu/Zn superoxide dismutase antioxidant enzymes. We show that there are two catalase genes and that each is differentially regulated both temporally and spatially during multicellular development. The catA gene is expressed throughout growth and development and its corresponding enzyme is maintained at a steady level. In contrast, the catB gene encodes a larger protein and is only expressed during the final stages of morphogenesis. Cell type fractionation showed that the CatB enzyme is exclusively localized to the prespore cells and the CatA enzyme is found exclusively in the prestalk cells. Each enzyme has a different subcellular localization. The unique developmental timing and cell type distribution suggest that the role for catB in cell differentiation is to protect the dormant spores from oxidative damage. We found that exposure to H(2)O(2) does not result in the induction of the catalase, superoxide dismutase, NER or BER mRNAs. A mutant with greatly reduced levels of catA mRNA and enzyme has greatly increased sensitivity to H(2)O(2) but normal sensitivity to UV. These results indicate that the natural resistance to oxidative stress is not due to an ability to rapidly raise the level of antioxidant or DNA repair enzymes and that the response to UV-light is independent from the response to reactive oxygen compounds.

Prospective evaluation of unexplained syncope, dizziness, and falls among community-dwelling elderly adults

BACKGROUND

Unexplained syncope, dizziness, and falls may present a difficult diagnostic challenge to primary care and emergency room physicians. The aim of this study was to evaluate a diagnostic algorithm in the assessment of a cohort of community-dwelling elderly people with symptoms of unexplained syncope, falls, or dizziness.

METHODS

Fifty-four consecutive elderly patients (mean age + SD = 76.4 + 8.0 years, range 61-91) were assessed over a 12-month period. Presenting symptoms were syncope in 33 patients (61.1%), unexplained falls without loss of consciousness in 10 patients (18.5%), and dizziness without loss of consciousness in 11 (20.4%), and true vertigo in 2 patients (3.7%). Patients were assessed systematically using the algorithm, followed up until a diagnosis was made, and appropriate preventive therapy or advice given.

RESULTS

Diagnoses were obtained in 41 patients (75.9%). Of the 33 patients with syncope, the cause was identified in 23 (69.7%) as follows: vasovagal in 12, arrhythmia in 5, hypotensive drugs in 3, orthostatic hypotension in 2, and major anxiety with hyperventilation in 1. The cause of syncope remained uncertain in 10 patients. Among the 10 patients with nonsyncopal falls, the cause was identified in 9 as follows: drop attacks with associated knee osteoarthritis or quadriceps muscle weakness in 3, orthostatic hypotension in 2, and single cases of cerebellar ataxia, Parkinson's disease, otologic vertigo, and vertebrobasilar insufficiency. Of 11 patients with dizziness, 4 had vasovagal syncope, 2 had orthostatic hypotension, 2 had otologic vertigo, one had carotid sinus syndrome, and the cause remained obscure in 2. Nineteen of the 41 patients (46.3%) had at least one other abnormality that was possibly contributory to their symptoms. Five of the 13 patients without a clearcut diagnosis had abnormalities of possible significance, including first-degree heart block with fascicular block in 2 patients and individual patients with severe hypertension, aortic valve disease, and vasodepressor carotid sinus hypersensitivity.

CONCLUSION

A targeted, problem-oriented algorithm indicates the diagnosis in three quarters of elderly patients with unexplained syncope, falls, and dizziness.

Combined radiofrequency ablation-cooling catheter for reversible cryothermal mapping and ablation

Reversible cryothermal mapping of cardiac arrhythmias has been performed intraoperatively. However, a steerable cooling catheter for reversible mapping has not yet been developed. We therefore developed and tested a cooling system consisting of a -15 degrees C hypertonic saline reservoir and a 7F steerable catheter also capable of radiofrequency (RF) ablation. Using excised ovine hearts placed in a 37 degrees C circulating saline bath, we measured the temperatures at depths of 0 mm, 1 mm, and 2 mm. The temperature after 90 seconds of cooling was 16.5 +/- 2.1 degrees C at 0 mm compared to 23.9 +/- 4.1 degrees C at 1 mm and 31.1 +/- 3.9 degrees C at 2 mm depth (p < 0.01). These data suggest that a 7F steerable combined RF ablation-cooling catheter may achieve temperatures suitable for mapping arrhythmias such as atrial tachycardias and right ventricular outflow tract tachycardias. Further enhancements to achieve lower temperatures at depth may be needed to reversibly map other arrhythmias such as left ventricular tachycardias.

Hypericin: a new laser phototargeting agent for human cancer cells

Laser activation of anthracycline-related drugs combines chemotherapy with photoablation for improved treatment. Hypericin, a structurally related anthraquinone, was tested for laser activation and cytotoxicity in human cancer cells. Viability of P3 squamous cell carcinoma cells incubated with 1 to 20 microgram/mL hypericin was reduced by more than 95% after 1 minute exposure at 4 degrees C to an argon laser (514 nm, 5 W), a KTP-532 laser (532 nm, 5 W), or a 20-A xenon lamp. Viability was reduced over 90% in six human carcinoma, sarcoma, and melanoma cell lines by this combined treatment, but only trace toxicity was seen after separate exposure to hypericin or light alone. These results show that hypericin is a sensitive agent for phototherapy of human cancer cells in vitro and indicate that this drug may be useful for tumor targeting via minimally invasive imaging-guided laser fiber optics.

Hypericin uptake in rabbits and nude mice transplanted with human squamous cell carcinomas: study of a new sensitizer for laser phototherapy

Tissue uptake and biodistribution of hypericin was measured in rabbits and in nu/nu mice xenografted with P3 human squamous cell carcinoma to assess the value of this dye as an in vivo sensitizer for laser photoinactivation of solid tumors. Hypericin has absorption maxima at 545 and 590 nm with a fluorescence emission peak at 640 nm in ethanol. Dye uptake after intravenous injection was tested at 4 and 24 hours in rabbit tissues by ethanol extraction and quantitative fluorescence spectrophotometry. Maximum dye levels were seen at 4 hours in most vascular organs with lung having fivefold higher uptake than spleen followed by liver, blood, and kidney. Mice were examined after 2, 4, 6, 8, and 24 hours and after 3 and 7 days for dye uptake. The peak concentration of hypericin in murine organs was reached at 4 hours with uptake per gram of tissue as follows: lung > spleen > liver > blood > kidney > heart > gut > tumor > stomach > skin > muscle > brain. Elimination of hypericin was rapid in most murine organs with residual dye under 10% of maximum by 7 days compared to 25% to 30% retention for the squamous cell tumors and several normal tissues. These results suggest that hypericin may be a useful photosensitizer for KTP/532 laser interstitial therapy of human cancer.

Evaluation of the preovulatory rise of follicle stimulating hormone and progesterone in normally ovulating women of reproductive age

Sixteen normally ovulating women of reproductive age were evaluated to determine the extent of the preovulatory FSH and progesterone rise in association with the LH surge. Highly significant differences were demonstrated between the baseline and peak preovulatory levels of both FSH and progesterone (P less than .0005). These significant peak ovulatory differences of FSH and progesterone were associated with a 2.5-fold rise (mean difference of 9.06 mIU/mL) of FSH and a 3.0-fold rise (mean difference of 1.94 ng/mL) of progesterone. These small, yet very significant, preovulatory increments of FSH and progesterone are important in the ovulatory process and the formation of an adequate corpus luteum.