Chronic kidney disease, dialysis and climate change.

Chronic Kidney Disease is a serious public health problem and in clear relation to Climate Change and ecosystem maintenance. Renal health is particularly vulnerable to the impacts of climate change, and dialysis therapy (hemodialysis and PD) has a significant environmental footprint, conditioned by energy consumption and greenhouse gas production. In the last 50 years, people have changed ecosystems faster and more extensively than in any other period in human history. It is a consequence of ever-increasing demand for food, fresh water, fuel, industry, etc. and the result has been a substantial and largely irreversible loss of the diversity of life on Earth. Since 1979, human activities have caused the extinction of 60% of mammals, birds, fish and reptiles. There is an urgent need to adopt "Green Nephrology" measures by developing sustainable environmental solutions for the prevention and treatment of kidney diseases.

Insulin resistance (HOMA-IR) cut-off values and the metabolic syndrome in a general adult population: effect of gender and age: EPIRCE cross-sectional study.

BACKGROUND: Insulin resistance has been associated with metabolic and hemodynamic alterations and higher cardio metabolic risk. There is great variability in the threshold homeostasis model assessment of insulin resistance (HOMA-IR) levels to define insulin resistance. The purpose of this study was to describe the influence of age and gender in the estimation of HOMA-IR optimal cut-off values to identify subjects with higher cardio metabolic risk in a general adult population. METHODS: It included 2459 adults (range 20-92 years, 58.4% women) in a random Spanish population sample. As an accurate indicator of cardio metabolic risk, Metabolic Syndrome (MetS), both by International Diabetes Federation criteria and by Adult Treatment Panel III criteria, were used. The effect of age was analyzed in individuals with and without diabetes mellitus separately. ROC regression methodology was used to evaluate the effect of age on HOMA-IR performance in classifying cardio metabolic risk. RESULTS: In Spanish population the threshold value of HOMA-IR drops from 3.46 using 90th percentile criteria to 2.05 taking into account of MetS components. In non-diabetic women, but no in men, we found a significant non-linear effect of age on the accuracy of HOMA-IR. In non-diabetic men, the cut-off values were 1.85. All values are between 70th-75th percentiles of HOMA-IR levels in adult Spanish population. CONCLUSIONS: The consideration of the cardio metabolic risk to establish the cut-off points of HOMA-IR, to define insulin resistance instead of using a percentile of the population distribution, would increase its clinical utility in identifying those patients in whom the presence of multiple metabolic risk factors imparts an increased metabolic and cardiovascular risk. The threshold levels must be modified by age in non-diabetic women.

Hyperbaric index in the primary prevention of hypertensive complications in high-risk pregnancy.

INTRODUCTION: Preeclampsia (PE) is a major cause of fetal morbidity and mortality. In the Western World, PE affects 2-7% of pregnancies and is responsible for 50,000 deaths annually. Early detection is a priority as it can change the clinical course, but there are no biomarkers or instrumental methods with high sensitivity and specificity. Only the hyperbaric index has a sensitivity and specificity of 99% for early identification of pregnant women at risk of developing PE, but its use is not widespread. OBJECTIVE: To assess the usefulness of the hyperbaric index in the primary prevention of hypertensive pregnancy complications in a public healthcare area. MATERIAL AND METHODS: This is a retrospective study of pregnancies that occurred in our area during the period 2007-2012 (N=11,784). The diagnosis was established by the hyperbaric index and pregnant women at risk were treated with ASA at night. RESULTS: In pregnant patients referred to the nephrology clinic (38.2%), diagnosed as high-risk for PE, and treated with 100mg ASA/night (from week 17), the incidence of PE episodes was reduced by 96.94.

Survival for haemodialysis vs. peritoneal dialysis and technique transference. Experience in Ourense, Spain, from 1976 to 2012.

OBJECTIVE: To assess SV in our RRT population in the period 1976-2012 as well as the influence of technique transference (TT). MATERIAL AND METHODS: The study included a retrospective cohort of 993 patients. Data were classified as transplant (Tx), change in technique, exitus or lost to follow-up. SV for TT was determined in patients with over 12 weeks of permanence. RESULTS: The mortality risk adjusted for age, sex, dialysis technique or diabetes mellitus (DM) showed that the estimated risk of death increased by 4.8% per year increase (HR=1.048; 95% CI: 1.04-1.06; P<.001) and was 44% higher in diabetics compared to non-diabetics (HR=1.44; 95% CI 1.16-1.76; P<.01). Regarding SV for TT, patients who initiated HD had a shorter survival than those who initiated PD and transferred to HD (P=.00563). CONCLUSION: In our experience, SV in RRT is dependent on age and coexistence of DM. It would be beneficial to reinstate the concept of "comprehensive care", in which RRT would start with PD and later transfer to HD.

Strategy to estimate risk progression of chronic kidney disease, cardiovascular risk, and referral to nephrology: the EPIRCE Study.

BACKGROUND: Although the prevalence of chronic kidney disease (CKD) is 10­14%, several prospective studies note a low rate of progression to end-stage renal disease (ESRD) in stages 3 and 4. A correct classification of risk of progression, based on demonstrated predictive factors, would allow better management of CKD. Recent studies have demonstrated the high predictive value of a classification that combines estimated (e) glomerular filtration rate (GFR) and urine albumin­creatinine ratio (ACR). We estimated the clinical risk of progression to ESRD and cardiovascular mortality predicted by the combined variable of eGFR and ACR in the Spanish general population. MATERIALS AND METHODS: This study was a cross-sectional evaluation in the Epirce sample, representative of Spanish population older than 20 years. GFR was estimated using MDRD and CKD-EPI formulas; microalbuminuria was considered to be an ACR 20­200 mg/g (men) or 30­300 mg/g (women) and macroalbuminuria was indicated beyond these limits. Population-weighted prevalence of risk of progression of CKD to ESRD was estimated. RESULTS: With MDRD, 1.4% of the adult Spanish population was at moderate risk of progression to ESRD, 0.1% at high risk, and 12.3% at low risk. With CKD-EPI, the moderate risk ratio rose to 1.7% and low risk to 12.6%, but high risk remained stable. CONCLUSIONS: The addition of ACR to eGFR best classifies the population at risk for renal impairment relative to Kidney/Disease Outcomes Quality Initiative grades 3 and 4. Estimating GFR with CKD-EPI modifies the distribution of low and moderate risk.

Cardiac troponin I and creatine kinase MB isoenzyme in patients with chronic renal failure.

OBJECTIVE: The aim of our study was to evaluate cut-off values for acute coronary syndrome (ACS) diagnosis in patients with chronic renal failure (CRF) for the cardiac biomarkers cardiac troponin I (cTnI) and creatine kinase MB isoenzyme (CK-MB) as compared to the cut-off values proposed by the manufacturers and those frequently used in the laboratory. METHOD: We performed a prospective study in patients with CRF with a glomerular filtration rate estimated by the MDRD-4 equation <60 mL/min and admitted with suspected acute coronary syndrome due to clinical history, physical examination, and electrocardiography. cTnI and CK-MB measurements were assessed upon hospitalisation and six months later using two different analytical methods (for cTnI: Access® and Vidas® analysers, and for CK-MB: Access® and Vitros® analysers). RESULTS: During the study period, 484 patients with CRF and suspected ACS were assessed. ACS was diagnosed in 12% of patients (58/484), while we found other cardiac pathologies (OCP) in 29% of patients (140/484) and other non-cardiac pathologies (ONCP) in 59% of patients (286/484). For cTnI assessed using the Access® analyser with the usual cut-off value (≥ 0.5 ng/mL), sensitivity was 43% and specificity was 94%, while for the proposed cut-off value (≥ 0.11 ng/mL), the values were 68% and 83%, respectively. For cTnI assessed using the Vidas® analyser with the usual cut-off value (≥ 0.11 ng/mL), sensitivity was 64% and specificity was 87%, while for the proposed cut-off value (≥ 0.06 ng/mL), the values were 75% and 79%, respectively. The sensitivity and specificity for both CK-MB were lower compared with cTnI. CONCLUSION: The cut-off values proposed in this study for both cTnI in patients with CRF (stage 3 to 5) to diagnose ACS are significantly different from that of the general population.

Insulin resistance index (HOMA-IR) levels in a general adult population: curves percentile by gender and age. The EPIRCE study.

AIMS: To describe the distribution of HOMA-IR levels in a general nondiabetic population and its relationships with metabolic and lifestyles characteristics. METHODS: Cross-sectional study. Data from 2246 nondiabetic adults in a random Spanish population sample, stratified by age and gender, were analyzed. Assessments included a structured interview, physical examination, and blood sampling. Generalized additive models (GAMs) were used to assess the effect of lifestyle habits and clinical and demographic measurements on HOMA-IR. Multivariate GAMs and quantile regression analyses of HOMA-IR were carried out separately in men and women. RESULTS: This study shows refined estimations of HOMA-IR levels by age, body mass index, and waist circumference in men and women. HOMA-IR levels were higher in men (2.06) than women (1.95) (P=0.047). In women, but not men, HOMA-IR and age showed a significant nonlinear association (P=0.006), with increased levels above fifty years of age. We estimated HOMA-IR curves percentile in men and women. CONCLUSIONS: Age- and gender-adjusted HOMA-IR levels are reported in a representative Spanish adult non-diabetic population. There are gender-specific differences, with increased levels in women over fifty years of age that may be related with changes in body fat distribution after menopause.