Rathika Krishnasamy

A randomised controlled trial of Heparin versus EthAnol Lock THerapY for the prevention of Catheter Associated infecTion in Haemodialysis patients – the HEALTHY-CATH trial

BackgroundTunnelled central venous dialysis catheter use is significantly limited by the occurrence of catheter-related infections. This randomised controlled trial assessed the efficacy of a 48 hour 70% ethanol lock vs heparin locks in prolonging the time to the first episode of catheter related blood stream infection (CRBSI).MethodsPatients undergoing haemodialysis (HD) via a tunnelled catheter were randomised 1:1 to once per week ethanol locks (with two heparin locks between other dialysis sessions) vs thrice per week heparin locks.ResultsObserved catheter days in the heparin (n=24) and ethanol (n=25) groups were 1814 and 3614 respectively. CRBSI occurred at a rate of 0.85 vs. 0.28 per 1000 catheter days in the heparin vs ethanol group by intention to treat analysis (incident rate ratio (IRR) for ethanol vs. heparin 0.17; 95%CI 0.02-1.63; p=0.12). Flow issues requiring catheter removal occurred at a rate of 1.6 vs 1.4 per 1000 catheter days in the heparin and ethanol groups respectively (IRR 0.85; 95% CI 0.20-3.5 p =0.82 (for ethanol vs heparin).ConclusionsCatheter survival and catheter-related blood stream infection were not significantly different but there was a trend towards a reduced rate of infection in the ethanol group. This study establishes proof of concept and will inform an adequately powered multicentre trial to definitively examine the efficacy and safety of ethanol locks as an alternative to current therapies used in the prevention of catheter-associated blood stream infections in patients dialysing with tunnelled catheters.Trial RegistrationAustralian New Zealand Clinical Trials Registry ACTRN12609000493246

Left Ventricular Global Longitudinal Strain (GLS) Is a Superior Predictor of All-Cause and Cardiovascular Mortality When Compared to Ejection Fraction in Advanced Chronic Kidney Disease

Background Echocardiographic global longitudinal strain (GLS) is increasingly recognised as a more effective technique than conventional ejection fraction (EF) in detecting subtle changes in left ventricular (LV) function. This study investigated the prognostic value of GLS over EF in patients with advanced Chronic Kidney Disease (CKD). Methods The study included 183 patients (57% male, 63% on dialysis) with CKD stage 4, 5 and 5Dialysis (D). 112 (61%) of patients died in a follow up of 7.8 ± 4.4 years and 41% of deaths were due to cardiovascular (CV) disease. GLS was calculated using 2-dimensional speckle tracking and EF was measured using Simpson’s biplane method. Cox proportional hazard models were used to assess the association of measures of LV function and all- cause and CV mortality. Results The mean GLS at baseline was -13.6 ± 4.3% and EF was 45 ± 11%. GLS was a significant predictor of all-cause [Hazard Ratio (HR) 1.09 95%; Confidence Interval (CI) 1.02–1.16; p = 0.01] and CV mortality (HR 1.16 95%; CI 1.04–1.30; p = 0.008) following adjustment for relevant clinical variables including LV mass index (LVMI) and EF. GLS also had greater predictive power for both all- cause and CV mortality compared to EF. Impaired GLS (>-16%) was associated with a 5.6-fold increased unadjusted risk of CV mortality in patients with preserved EF. Conclusions In this cohort of patients with advanced CKD, GLS is a more sensitive predictor of overall and CV mortality compared to EF. Studies of larger populations in CKD are required to confirm that GLS provides additive prognostic value in patients with preserved EF.

The association between left ventricular global longitudinal strain, renal impairment and all-cause mortality

BACKGROUND Left ventricular (LV) systolic dysfunction is an important predictor of cardiovascular death. Global longitudinal strain (GLS) is a widely available echocardiographic technique proven to be more sensitive than conventional ejection fraction (EF) in detecting subtle changes in LV function. However, the prognostic value of GLS in patients with chronic kidney disease (CKD) is unknown. METHODS We studied 447 patients from a single center who were stratified according to estimated glomerular filtration rate (eGFR). GLS was calculated using two-dimensional speckle tracking and EF was measured using Simpsons biplane. Cox proportional hazard model was used to identify independent predictors of survival and measures of discrimination and reclassification were used to assess the predictive value of GLS. Multivariable regression models were used to evaluate clinical and laboratory factors associated with GLS. RESULTS The mean EF was 58 ± 11% and GLS was -16.6 ± 4.2%. eGFR correlated negatively with GLS (r = -0.14, P = 0.004). Factors that were independently associated with GLS include gender, previous myocardial infarction, eGFR and phosphate (R(2) = 0.16, P < 0.001). Sixty-four patients died in a follow-up of 5.2 ± 1.4 years. GLS remained a significant predictor of all-cause mortality [hazard ratio (HR) 1.08, 95% confidence interval (CI) 1.01-1.15] following adjustment for age, diabetes mellitus, hypertension, eGFR and left ventricular mass index (LVMI). The strength of association between demographic data, eGFR, LVMI and mortality increased following addition of GLS [c-statistic 0.68 (95% CI 0.61-0.74) to 0.71 (95% CI 0.64-0.77), P = 0.04]. Addition of GLS also demonstrated a 21% net reclassification improvement in risk prediction for all-cause mortality over clinical factors. CONCLUSIONS GLS is an important predictor of all-cause mortality in CKD patients. Traditional and non-traditional risk factors such as phosphate are important determinants of GLS. Strain assessment in CKD patients may provide greater cardiovascular risk stratification.

Daily Variation in Death in Patients Treated by Long-term Dialysis: Comparison of In-Center Hemodialysis to Peritoneal and Home Hemodialysis

BACKGROUND There has been little study to date of daily variation in cardiac death in dialysis patients and whether such variation differs according to dialysis modality and session frequency. STUDY DESIGN Observational cohort study using ANZDATA (Australia and New Zealand Dialysis and Transplant) Registry data. SETTING & PARTICIPANTS All adult patients with end-stage kidney failure treated by dialysis in Australia and New Zealand who died between 1999 and 2008. PREDICTORS Timing of death (day of week), dialysis modality, hemodialysis (HD) session frequency, and demographic, clinical, and facility variables. OUTCOMES & MEASUREMENTS Cardiac and noncardiac mortality. RESULTS 14,636 adult dialysis patients died during the study period (HD, n = 10,338; peritoneal dialysis [PD], n = 4,298). Cardiac death accounted for 40% of deaths and was significantly more likely to occur on Mondays in in-center HD patients receiving 3 or fewer dialysis sessions per week (n = 9,503; adjusted OR, 1.26; 95% CI, 1.14-1.40; P < 0.001 compared with the mean odds of cardiac death for all days of the week). This daily variation in cardiac death was not seen in PD patients, in-center HD patients receiving more than 3 sessions per week (n = 251), or home HD patients (n = 573). Subgroup analyses showed that deaths related to hyperkalemia and myocardial infarction also were associated with daily variation in risk in HD patients. This pattern was not seen for vascular, infective, malignant, dialysis therapy withdrawal, or other deaths. LIMITATIONS Limited covariate adjustment. Residual confounding and coding bias could not be excluded. Possible type 2 statistical error due to limited sample size of home HD and enhanced-frequency HD cohorts. CONCLUSIONS Daily variation in the pattern of cardiac deaths was observed in HD patients receiving 3 or fewer dialysis sessions per week, but not in PD, home HD, and HD patients receiving more than 3 sessions per week.

Impact of non‐traditional phosphate binders and cinacalcet on haemodialysis patient biochemistry, pill burden and cost

Aim:  The Australian Pharmaceutical Benefits Scheme (PBS) commenced cost subsidization for haemodialysis patients of sevelamer in December 2007, cinacalcet in July 2008 and lanthanum in May 2009. To determine the impact of PBS listing of these medications, we performed a single centre cross‐sectional, longitudinal study.

Nephrology training in Australia and New Zealand: a survey of outcomes and adequacy

Advanced training programmes in nephrology should provide broad exposure to all aspects of nephrology. In Australia and New Zealand (ANZ), the Advanced Training Committee in Nephrology oversees training, and recent increases in trainee numbers have led to concern about dilution of experience.

Feasibility of higher intensity exercise in patients with chronic kidney disease

BACKGROUND Higher intensity exercise is a more effective way of evoking improvements in cardiorespiratory fitness in many chronic disease populations compared to moderate intensity continuous training. The aim of this study was to investigate the feasibility of participation in higher intensity exercise in patients with chronic kidney disease (CKD). METHODS This study is an observational sub-study of the intervention arm of a randomized control trial. Forty-four participants with stage 3-4 CKD in the intervention arm were required to complete a predominantly home-based 12 month individualized exercise intervention. Physical activity levels, exercise capacity (METs) and blood biochemistry were measured at baseline and 12 months. The physical activity groups (higher intensity, moderate intensity and not meeting guidelines) were determined from the six months activity prior to the 12 month testing visit. RESULTS At 12 months, the number of patients who reported performing weekly higher intensity exercise in the previous six months of the intervention increased by 23%. Participants completing higher intensity exercise had a significantly greater exercise capacity at 12 months (11.9±3.7 METs) than participants reporting moderate intensity exercise and those not meeting guidelines (9.2±1.7, 7.6±3.2 METs). Hemoglobin levels and exercise capacity were significantly higher at baseline in patients who reported exercising at higher intensities (142.9±16.1 g/L and 9.8±4.2 METs) compared to those reporting moderate intensity exercise (129.8±12.9 g/L and 8±3.1 METs) and not meeting guidelines (127.3±12.5 g/L and 6±2 METs). CONCLUSIONS The study was successful in increasing higher intensity physical activity in a large proportion of patients with CKD.

Association between left ventricular global longitudinal strain, health‐related quality of life and functional capacity in chronic kidney disease patients with preserved ejection fraction

Patients with chronic kidney disease (CKD) have a significant burden of dyspnoea and fatigue in spite having normal left ventricular (LV) ejection fraction (EF). Global longitudinal strain (GLS) can detect subtle changes in LV function. This study aimed to evaluate the relationship between LV function, functional capacity and quality of life (QOL) in CKD patients with preserved EF.

Low socioeconomic status adversely effects dialysis survival in Australia

Low socio‐economic status (SES) is associated with increased incidence of end‐stage kidney disease and in the USA, poorer dialysis survival. All Australians have access to a universal healthcare system.

Impact of pay-for-performance on access at first dialysis in Queensland

Commencement of haemodialysis with an arteriovenous fistula (AVF) or arteriovenous graft (AVG) is associated with improved survival compared with commencement with a central venous catheter. In 2011–2012, Queensland Health made incentive payments to renal units for early referred patients who commenced peritoneal dialysis (PD), or haemodialysis with an AVF/AVG. The aim of this study was to determine if pay for performance improved clinical care.