Impact of the clinical conditions at dialysis initiation on mortality in incident haemodialysis patients: a national cohort study in Taiwan

BACKGROUND

Glomerular filtration rate (GFR) and co-morbidity at dialysis initiation in relation to mortality in end-stage renal disease is still controversial. We studied factors potentially related to the mortality in incident haemodialysis (HD) patients.

METHODS

A national database included 23 551 incident HD patients from July 2001 to December 2004. Kaplan-Meier and Cox regression analyses were performed to assess the association between GFR estimated by the four-variable Modified Diet in Renal Disease equation and all-cause mortality. Analyses were performed from Day 91 after the start of dialysis. Patients were classified into five groups (quintiles) based on estimated glomerular filtration rate (eGFR) at the start of dialysis.

RESULTS

The median eGFR at dialysis initiation was low (4.7 mL/min/1.73 m(2)), as was the mortality in the first year of dialysis [13.2/100 patient-year, 95% confidence interval (95% CI) = 12.8-13.7]. There was an inverse association between lower eGFR and higher survival rate. The Cox regression model revealed an increase in mortality risk in Q5 (hazard ratio [HR] = 2.44, 95% CI = 2.11-2.81), Q4 (HR = 1.66, 95% CI = 1.43-1.93), Q3 (HR = 1.21, 95% CI = 1.04-1.41) and Q2 (HR = 1.18, 95% CI = 1.01-1.37) compared with the reference group of Q1 after adjusting for year of application, primary diseases (chronic glomerulonephritis, diabetic nephropathy, hypertension, chronic tubulointerstitial nephritis and others), demographics (age, sex), presence of co-morbidity (diabetes mellitus, hypertension, congestive heart failure, ischaemic heart diseases, cerebrovascular diseases, malignancies, liver cirrhosis, tuberculosis, other diseases and free of reported of co-morbidities) and haematocrit. Propensity score analysis also showed a higher eGFR to be associated with increased mortality risks. Adjustment for all covariates explained a high percentage of excess risk of mortality in the groups with low eGFR, but less risk in the groups with higher eGFR.

CONCLUSIONS

Lower eGFR at dialysis initiation is associated with lower mortality. Conditions at dialysis initiation explained excess 1-year mortality risk differently in patients who began dialysis at different levels of eGFR. Other factors likely contribute to the mortality of patients initiating dialysis at higher eGFR levels, and further study is needed.

Association of statin use and development of renal dysfunction in type 2 diabetes--the Hong Kong Diabetes Registry

AIM

Dyslipidaemia may be a risk factor for diabetic kidney disease. We examined prospectively association between the use of statins and development of renal dysfunction in type 2 diabetes.

METHODS

A consecutive cohort of 5264 diabetic patient recruited between 1996 and 2005 underwent detailed assessments. Renal dysfunction was defined as first estimated glomerular filtration rate <60 ml/min/1.73 m(2), or, the first hospitalisation with a diagnosis of renal disease as coded by the International Classification of Disease, Ninth Revision. Drug use was quantified using the proportion of exposure time from baseline to event/death/censored time, as appropriate.

RESULTS

In this cohort (male: 47.3%, median age: 55 years, median duration of diabetes: 6.0 years), none had renal dysfunction at baseline. During a median follow-up period of 4.9 (quartiles: 2.77, 7.04) years, 703 patients (13.4%) developed renal dysfunction, 1275 patients (22.2%) were exposed to statins. After controlling for baseline risk factors, multivariable adjusted hazard ratio of statin use for development of renal dysfunction was 0.32 (95% CI 0.21-0.50, p<0.0001).

CONCLUSION

Use of statins was associated with reduced risk of developing renal dysfunction in type 2 diabetes and this association was independent of baseline risk factors.

New insights in glomerular filtration rate formulas and chronic kidney disease classification

BACKGROUND

The MDRD Study equation is the most popular equation for estimating the glomerular filtration rate (eGFR) from serum creatinine (Scr), age, sex and race. Many articles deal with ethnic factors, correcting the MDRD Study equation for different populations, with more or less success. The new CKD-EPI equation introduced the concept of a population-normalized Scr in the eGFR equation for white men (Scr/0.90) and white women (Scr/0.70).

METHODS

We introduce alternative mathematical forms for the MDRD Study equation and the CKD-EPI equation, using the concept of a population-normalized Scr, resulting in a more general and mathematically less complicated form for the eGFR equation.

RESULTS

We show that the normalization constant corresponds to the mean Scr-value for the specific healthy population. We compared the established equations with the new alternative forms, and show that the differences are minimal. The sex/race dependency is completely comprehended in the normalization constant, making the alternative eGFR equations independent of sex and race.

CONCLUSION

The age-dependency of eGFR remains and consequently age-dependent cutoff values for the classification of Chronic Kidney Disease (CKD) look more appropriate, contrary to the current classification rules. The population-normalized Scr which is independent of age, sex and race may serve as an alternative for the classification of CKD.

From design to implementation--the Joint Asia Diabetes Evaluation (JADE) program: a descriptive report of an electronic web-based diabetes management program

BACKGROUND

The Joint Asia Diabetes Evaluation (JADE) Program is a web-based program incorporating a comprehensive risk engine, care protocols, and clinical decision support to improve ambulatory diabetes care.

METHODS

The JADE Program uses information technology to facilitate healthcare professionals to create a diabetes registry and to deliver an evidence-based care and education protocol tailored to patients' risk profiles. With written informed consent from participating patients and care providers, all data are anonymized and stored in a databank to establish an Asian Diabetes Database for research and publication purpose.

RESULTS

The JADE electronic portal (e-portal: http://www.jade-adf.org) is implemented as a Java application using the Apache web server, the mySQL database and the Cocoon framework. The JADE e-portal comprises a risk engine which predicts 5-year probability of major clinical events based on parameters collected during an annual comprehensive assessment. Based on this risk stratification, the JADE e-portal recommends a care protocol tailored to these risk levels with decision support triggered by various risk factors. Apart from establishing a registry for quality assurance and data tracking, the JADE e-portal also displays trends of risk factor control at each visit to promote doctor-patient dialogues and to empower both parties to make informed decisions.

CONCLUSIONS

The JADE Program is a prototype using information technology to facilitate implementation of a comprehensive care model, as recommended by the International Diabetes Federation. It also enables health care teams to record, manage, track and analyze the clinical course and outcomes of people with diabetes.

The role of primary care in the management of the chronic kidney disease population

With the recognition of the high prevalence of CKD and its associated morbidity and mortality, increasing attention has focused on how to optimally provide care to this population. An immediate concern is that the sheer size of the population with early-stage CKD will overwhelm the capacity of the current nephrology workforce. Thus, the burden of care for most CKD patients will likely have to fall on primary care physicians (PCPs). This article reviews the issues surrounding the role of primary care in the management of the CKD population. Topics covered include specific roles that PCPs can play in the care of CKD patients, barriers and challenges to PCP involvement, and a discussion of strategies to improve the care provided to CKD patients by PCPs.

Burden of chronic kidney disease: an international perspective

CKD is associated with increased cardiovascular mortality and a loss of disability-adjusted life years. Diseases of the genitourinary system were responsible for 928,000 deaths and 14,754,000 disability-adjusted life years in 2004. However, the absence of kidney registries in most of the low- and middle-income countries has made it difficult to ascertain the true burden of CKD in these countries. The global increase in the incidence and prevalence of CKD is being driven by the global increase in the prevalence of diabetes mellitus, hypertension, obesity, and aging. Most patients in low- and middle-income countries die because they cannot access renal replacement therapy because of the exorbitant cost. Community surveys have shown that the number of people with end-stage kidney disease is just the tip of the "CKD iceberg." The preventive strategies to stem the tide of CKD should involve educating the population on how to prevent renal disease; identifying those at risk of developing CKD; raising the awareness of the general public, policy makers, and health care workers; modifying the lifestyle of susceptible individuals; detecting early stage of CKD; arresting or hindering the progression of disease; and creating facilities for global assistance.

Associations of hyperglycemia and insulin usage with the risk of cancer in type 2 diabetes: the Hong Kong diabetes registry

OBJECTIVE Insulin has mitogenic effects, although hyperglycemia may be a risk factor for cancer in type 2 diabetes. It remains uncertain whether use of insulin increases cancer risk because of its effect on cell growth and proliferation or decreases cancer risk because of its glucose-lowering effect. RESEARCH DESIGN AND METHODS A 1:2-matched new insulin user cohort on age (+/-3 years), smoking status, and likelihood of initiating insulin therapy (+/-0.05) was selected from a cohort of 4,623 Chinese patients with type 2 diabetes, free of cancer, and naive to insulin at enrollment. Stratified Cox regression analysis on the matched pairs was used to obtain hazard ratios (HRs) of insulin therapy and A1C for cancer risk. A structured adjustment scheme was used to adjust for covariates. RESULTS Of 973 new insulin users, 971 had matched nonusers (n = 1935). The cancer incidence in insulin nonusers was much higher than that in insulin users (49.2 vs. 10.2, per 1,000 person-years, P < 0.0001). After further adjustment for all other covariates with a P value less than 0.3 and nonlinear associations with cancer, A1C was associated with an increased cancer risk (HR per percentage 1.26, 95% CI 1.03-1.55), whereas use of insulin was associated with a decreased cancer risk (HR of insulin users vs. nonusers: 0.17, 0.09-0.32). Consistent results were found in analyses including all 973 insulin users and 3,650 nonusers. CONCLUSIONS In Chinese patients with type 2 diabetes, hyperglycemia predicts cancer, whereas insulin usage was associated with a reduced cancer risk.

Hyperuricemia and metabolic syndrome: associations with chronic kidney disease

The effects of serum uric acid (SUA) and metabolic syndrome on chronic kidney disease (CKD) remain controversial. This study grouped subjects according to a combination of their uric acid and metabolic syndrome status and investigated the association between these groups and CKD to clarify the relationships of SUA and metabolic syndrome to CKD. This survey analyzed data from 81,799 adults (45,148 men and 36,651 women) who underwent health examinations at Chang Gung Memorial Hospital, in northern Taiwan, from 2000 through 2007. Hyperuricemia was defined as an SUA greater than 7.7 mg/dL in men or greater than 6.6 mg/dL in women. Patients were classified by uric acid-metabolic syndrome status as follows: A = no hyperuricemia and no metabolic syndrome, B = presence of metabolic syndrome but not hyperuricemia, C = presence of hyperuricemia but no metabolic syndrome, and D = presence of both hyperuricemia and metabolic syndrome. Kidney function was assessed in terms of the estimated glomerular filtration rate (eGFR) by using the Modification of Diet in Renal Disease Study equation modified for Chinese. CKD was defined as an eGFR <60 mL/min/1.73 m(2). The prevalences of hyperuricemia, metabolic syndrome, and CKD were 22.8% (26.3% in men and 18.6% in women), 13.5% (15.0% in men and 11.6% in women), and 2.2% (2.1% in men and 2.2% in women), respectively. In men, the age-adjusted odds ratios for CKD, with group A as reference, were 1.95 for group B, 4.86 for group C, and 5.85 for group D. In women, the age-adjusted odds ratios were 1.96 for group B, 6.66 for group C, and 9.01 for group D. Hyperuricemia is strongly associated with CKD, independent of the presence of metabolic syndrome.

[Epidemiology of chronic kidney disease in the Democratic Republic of Congo: review of cross-sectional studies from Kinshasa, the capital]

Chronic kidney disease (CKD) is a worldwide public health problem. Little is known about its burden in Africa. This paper reviews the knowledge of CKD in Kinshasa, summarizing four studies undertaken in the general population and traditional health system of Kinshasa. CKD was defined by either kidney damage (proteinuria> or =300 mg/day) or reduced kidney function (eGFR<60 ml/min/1.73 m(2)). In the general population, the prevalence of CKD all stage is 12.4 %. Our work shows also the high prevalence of proteinuria among subjects who do not have diabetes or hypertension, the lack of early detection and management of CKD risk factors in the traditional health care system leading to late referral or premature deaths, and the limits of renal replacement treatment. CKD affects young people in the DRC, in contrast to the United States, where CKD is more prevalent in older people. Major determinants of CKD in our studies were hypertension, diabetes, overweight, age, lower socioeconomic status, and Human immunodeficiency virus (HIV) infection. Glomerular nephropathy (mainly focal segmental glomerulosclerosis) remains the leading cause of end stage renal disease. An annual screening of the population for proteinuria and CKD risk factors is feasible and will, it is hoped, provide the basis for building a nationwide prevention strategy.

Association of hepatitis C and B virus infection with CKD in an endemic area in Taiwan: a cross-sectional study

BACKGROUND

Hepatitis B virus (HBV) and hepatitis C virus (HCV) infections may lead to nephropathy. However, the association between different types of viral hepatitis and chronic kidney disease (CKD) is not well established.

STUDY DESIGN

Cross-sectional study.

SETTING & PARTICIPANTS

A large-scale community study with 54,966 adults in a Taiwanese county endemic for HBV and HCV infection.

PREDICTOR

HCV infection alone, HBV infection alone, HBV/HCV coinfection, and neither.

OUTCOMES

Proteinuria (urine protein, >or=1+), low (<60 mL/min/1.73 m(2)) estimated glomerular filtration rate (eGFR), and CKD (proteinuria or eGFR <60 mL/min/1.73 m(2)).

MEASUREMENTS

HBV and HCV infection were defined as a seropositive test result for hepatitis B surface antigen and HCV antibody. Proteinuria was assessed using a repeated dipstick method. eGFR was computed using the 4-variable Modification of Diet in Renal Disease (MDRD) Study equation.

RESULTS

Mean age of the study group was 60.8 years. Prevalences of HCV infection alone, HBV infection alone, HBV/HCV coinfection, and neither were 9.4%, 9.9%, 0.9%, and 79.8%, respectively. 2,994 (5.4%), 7,936 (14.5%), and 9,602 (17.5%) participants had proteinuria, low eGFR, and CKD, respectively. Multivariate logistic regression analyses showed that HCV infection alone (OR, 1.26; 95% CI, 1.17-1.38), but not HBV infection alone (OR, 1.04; 95% CI, 0.96-1.14) or HBV/HCV coinfection (OR, 1.12; 95% CI, 0.87-1.45), was an independent risk factor for CKD. The prevalence of HCV seropositivity was higher in later CKD stages, changing from 8.5% in CKD stage 1 to 14.5% in CKD stages 4-5. Adjusted ORs for HCV infection alone were 1.14 (95% CI, 1.003-1.300) for proteinuria and 1.30 (95% CI, 1.20-1.42) for low eGFR.

LIMITATIONS

The definition of CKD status requires a 3-month duration of low eGFR or kidney damage; this was presumed, not documented, in this study.

CONCLUSIONS

HCV infection, but not HBV infection, was associated significantly with prevalence and disease severity of CKD in this HBV and HCV endemic area.

Early recognition and prevention of chronic kidney disease

Chronic kidney disease is a common disorder and its prevalence is increasing worldwide. Early diagnosis on the basis of presence of proteinuria or reduced estimated glomerular filtration rate could permit early intervention to reduce the risks of cardiovascular events, kidney failure, and death that are associated with chronic kidney disease. In developed countries, screening for the disorder is most efficient when targeted at high-risk groups including elderly people and those with concomitant illness (such as diabetes, hypertension, or cardiovascular disease) or a family history of chronic kidney disease, although the role of screening in developing countries is not yet clear. Effective strategies are available to slow the progression of chronic kidney disease and reduce cardiovascular risk. Treatment of high blood pressure is recommended for all individuals with, or at risk of, chronic kidney disease. Use of angiotensin-converting-enzyme inhibitors or angiotensin-receptor blockers is preferred for patients with diabetic chronic kidney disease or those with the proteinuric non-diabetic disorder. Glycaemic control can help prevent the onset of early stages of chronic kidney disease in individuals with diabetes. Use of statins and aspirin is beneficial for most patients with chronic kidney disease who are at high cardiovascular risk, although research is needed to ascertain how to best prevent cardiovascular disease in this cohort. Models of care that facilitate delivery of the many complex aspects of treatment simultaneously could enhance management, although effects on clinical outcomes need further assessment. Novel clinical methods to better identify patients at risk of progression to later stages of chronic kidney disease, including kidney failure, are needed to target management to high-risk subgroups.

Differences in progression of CKD and mortality amongst Caucasian, Oriental Asian and South Asian CKD patients

BACKGROUND

Ethnic differences in chronic kidney disease (CKD) progression are not well characterized but are of interest across and within countries.

METHODS

We followed up a large CKD cohort of patients of three different ethnic origins [Caucasian, Oriental Asian (OA) and South Asian (SA)] from time of nephrology referral in a universal health care system. Key outcomes were time to death and/or renal replacement therapy (RRT) and rate of decline in estimated GFR (eGFR). The effects of known predictors (blood pressure, proteinuria, age, sex, diabetes, cardiovascular disease and medications) and of other laboratory abnormalities were assessed using multivariate modelling techniques, including both Cox proportional hazards and competing risk approach.

RESULTS

The cohort comprised 3444 patients (2626 Caucasians, 397 OA and 421 SA). All-cause mortality rates are higher in Caucasians than SA or OA [hazard ratio (HR) 0.693 and 0.803, P < 0.05]. OA and SA have higher risks of progressing to RRT (HR 1.281 and 1.349, P < 0.05) and lower risks of death before RRT (HR 0.718 and 0.520, P < 0.05) compared to Caucasians after adjustment for usual risk factors. However, when adjusted for additional laboratory abnormalities, differences did not persist for progression, but did for survival advantage of Asians. The median rate of decline in eGFR (in millilitres per minute per 1.73 m(2)) was significantly slower in Caucasians (-2.11) than in OA (-2.93) or SA (-3.56), P = 0.027.

CONCLUSIONS

Asians appear to have faster CKD progression and lower mortality rates compared to Caucasians. This effect is not explained by the usual variables, but rates of progression may be related to differences in severity of laboratory abnormalities at different CKD stages. Further research is needed to understand the implications of these findings.

Tacrolimus combined with corticosteroids in treatment of nephrotic idiopathic membranous nephropathy: a multicenter randomized controlled trial

BACKGROUND

Idiopathic membranous nephropathy (IMN), a common cause of nephrotic syndrome in adults, is usually treated with corticosteroids in combination with cyclophosphamide or cyclosporine. A recent placebo-controlled study suggested that tacrolimus monotherapy was effective in IMN. However, the effectiveness of tacrolimus versus classic regimen and its potential nephrotoxicity remain inconclusive. This study evaluated the efficacy and safety of tacrolimus plus prednisone in patients with nephrotic IMN.

METHODS

Seventy-three patients with nephrotic IMN were recruited in this multicenter randomized controlled trial, 39 receiving tacrolimus and prednisone, while 34 receiving cyclophosphamide and prednisone. Tacrolimus was given at 0.1 mg/kg/d initially and adjusted to a blood trough level at 5 to 10 ng/mL for 6 months and then reduced to 2 to 5 ng/mL in the subsequent 3 months.

RESULTS

Intention-to-treat analysis suggested that the remission rate at the end of the sixth month was significantly higher in tacrolimus group than that in cyclophosphamide group (85% versus 65%, P < 0.05). The decrease of proteinuria was significantly greater in tacrolimus group. At the end of the 12th month, the remission rates were comparable between these 2 groups. Patients treated with tacrolimus were more likely to develop glucose intolerance (or diabetes mellitus), infection, and hypertension. No obvious nephrotoxicity of calcineurin inhibitor was found in repeat renal biopsy.

CONCLUSIONS

Tacrolimus plus corticosteroids is an alternative therapeutic regimen for nephrotic IMN. The short-term efficacy might be better than cyclophosphamide plus prednisone.

Independent predictive roles of eotaxin Ala23Thr, paraoxonase 2 Ser311Cys and beta-adrenergic receptor Trp64Arg polymorphisms on cardiac disease in Type 2 Diabetes--an 8-year prospective cohort analysis of 1297 patients

AIMS

To examine the independent and joint effects of multiple genetic variants on a cardiac end-point in an 8-year prospective study of a Chinese diabetic cohort.

METHODS

Seventy-seven single nucleotide polymorphisms (SNPs) of 53 candidate genes for inflammation, thrombosis, vascular tone regulation and lipid metabolism were genotyped in 1297 Chinese patients with no prior history of coronary heart disease (CHD) or heart failure at baseline. Cardiac end-point was defined by the occurrence of CHD and/or heart failure.

RESULTS

In Cox regression model, after adjustment for baseline confounding variables including age, sex, smoking status, duration of diabetes, glycaemic control, lipid levels, waist circumference, blood pressure, albuminuria and estimated glomerular filtration rate, genetic variants, including Ala/Ala of SCYA11 (eotaxin) Ala23Thr, Cys/Cys or Cys/Ser of PON2 (paraoxonase 2) Ser311Cys and Arg/Arg of ADRB3 (beta3-adrenergic receptor) Trp64Arg, were independently associated with incident cardiac end-point, with respective hazard ratios (95% confidence interval) of 1.70 (1.10-2.61, P=0.037), 1.42 (1.08-1.88, P=0.013) and 3.84 (1.18-12.50, P=0.025). Analysis of the joint effect of the risk alleles showed significant increased risk of the cardiac end-point with increasing number of risk alleles (P<0.001). The adjusted risk for the cardiac end-point was 4.11 (P=0.002) for patients carrying four risk alleles compared with those carrying one or no risk allele.

CONCLUSIONS

The independent risk conferred by genetic variants encoding pathways such as inflammation and lipid metabolism, not adequately reflected by conventional biomarkers, may identify high-risk individuals for intensified control of modifiable risk factors.

Non-invasive estimation of glomerular filtration rate (GFR). The Lund model: Simultaneous use of cystatin C- and creatinine-based GFR-prediction equations, clinical data and an internal quality check

Knowledge of glomerular filtration rate (GFR) is required to detect and follow impairment of renal function, to allow correct dosage of drugs cleared by the kidneys, and for the use of nephrotoxic contrast media. Correct determination of GFR requires invasive techniques, which are expensive, slow and not risk-free. Therefore, GFR-prediction equations based solely upon cystatin C or creatinine and anthropometric data or upon cystatin C, creatinine and anthropometric data have been developed. The combined prediction equations display the best diagnostic performance, but in several easily identifiable clinical situations (e.g. abnormal muscle mass, treatment with large doses of glucocorticoids) prediction equations based upon either cystatin C or creatinine are better than the combined equations. In Lund, where cystatin C has been used as a GFR-marker in the clinical routine since 1994, a strategy based upon this knowledge has therefore been developed. This comprises simultaneous use of a cystatin C-based and a creatinine-based GFR-prediction equation. If the GFRs predicted agree, the mean value is used as a reliable GFR-estimate. If the GFRs predicted do not agree, clinical data is evaluated to identify reasons for not using one of the two prediction equations and the GFR predicted by the other one is used. If no reasons for the difference in predicted GFRs are found, an invasive gold standard determination of GFR is performed. If the GFRs predicted agree for a patient, the creatinine value is reliably connected to a specific GFR and can be used to follow changes in GFR of that patient.

Percutaneous continuous ambulatory peritoneal dialysis (CAPD) catheter insertion – a preferred option for developing countries

Continuous ambulatory peritoneal dialysis (CAPD) as a modality of renal replacement therapy in patients with chronic kidney disease stage 5 (CKD 5) has the advantage of being a home-based therapy and is a preferred option in patients with inadequate access to haemodialysis and transplantation facilities and in those infected with HIV and other blood-borne viruses. While open surgical CAPD catheter placement has been the conventional mainstay of access placement, percutaneous techniques are being increasingly used with similar success rates. We report our experience over the past two years with blind insertion of the swan neck percutaneous double-cuffed Tenckhoff CAPD catheter using a trocar. There was considerable decrease in hospital stay and surgical costs. There was only one major complication of injury to the jejunal mesenteric artery requiring emergency laparotomy in one patient. In three patients, drain of peritoneal fluid was inadequate, presumably due to omental wrapping around the in-dwelling catheter, and required surgical removal of the omentum.

Prevalence of CKD and comorbid illness in elderly patients in the United States: results from the Kidney Early Evaluation Program (KEEP)

BACKGROUND

Elderly individuals with chronic kidney disease (CKD) have high rates of comorbid conditions, including cardiovascular disease and its risk factors, and CKD-related complications. In individuals aged > or = 65 years, we sought to describe the prevalence of CKD determined from laboratory test results in the Kidney Early Evaluation Program (KEEP; n = 27,017) and National Health and Nutrition Examination Survey (NHANES) 1999-2006 (n = 5,538) and the prevalence of diagnosed CKD determined from billing codes in the Medicare 5% sample (n = 1,236,946). In all 3 data sources, we also explored comorbid conditions and CKD-related complications.

METHODS

CKD was identified as decreased estimated glomerular filtration rate (<60 mL/min/1.73 m(2)) or increased albumin-creatinine ratio in KEEP and NHANES; CKD was identified using International Classification of Diseases, Ninth Revision, Clinical Modification codes in Medicare. Investigated comorbid conditions included diabetes, hypertension, high cholesterol level, coronary artery disease, congestive heart failure, cerebrovascular disease, peripheral vascular disease, and cancer, and CKD-related complications included anemia, hypocalcemia, hyperphosphatemia, and hyperparathyroidism.

RESULTS

The prevalence of CKD was approximately 44% in both KEEP and NHANES participants, and the prevalence of diagnosed CKD was 7% in Medicare beneficiaries. In all 3 data sets, the prevalence of CKD or diagnosed CKD was higher in participants aged > or = 80 years and those with comorbid conditions. For KEEP and NHANES participants, the prevalence of most comorbid conditions and CKD complications increased with decreasing estimated glomerular filtration rate. For participants with CKD stages 3-5, a total of 29.2% (95% CI, 27.8-30.6) in KEEP and 19.9% (95% CI, 17.0-23.1) in NHANES had anemia, 0.7% (95% CI, 0.4-0.9) and 0.6% (95% CI, 0.3-1.3) had hypocalcemia, 5.4% (95% CI, 4.7-6.1) and 6.4% (95% CI, 5.1-8.0) had hyperphosphatemia, and 52.0% (95% CI, 50.4-53.6) and 30.0% (95% CI, 25.9-34.3) had hyperparathyroidism, respectively.

CONCLUSIONS

CKD is common in the elderly population and is associated with high frequencies of concomitant comorbid conditions and biochemical abnormalities. Because CKD is not commonly diagnosed, greater emphasis on physician education may be beneficial.

Measuring vs estimating glomerular filtration rate in kidney transplantation

Evaluation of kidney function is crucial in the care of kidney transplant recipients and in the design and interpretation of clinical trials in transplantation. Kidney function is most commonly assessed in both instances using serum creatinine concentration or an estimate of glomerular filtration rate (GFR) based on serum creatinine. These are inexpensive, widely available, and easily administered. Both have significant drawbacks, notably with respect to their inability to accurately identify changes in GFR. Novel markers of GFR such as cystatin C and beta-trace protein show promise as accurate and sensitive markers of GFR but have not yet been adequately evaluated in kidney transplantation. In addition, they are relatively expensive compared to creatinine and their assays are not available in most clinical laboratories. Glomerular filtration rate measurement using a variety of different available tracers and techniques is infrequently used in either clinical care or research protocols because of its cost and cumbersomeness. This review will discuss the merits and pitfalls of the various tools available to evaluate GFR in kidney transplantation.

Reperfusion Strategy and Mortality in ST-Elevation Myocardial Infarction among Patients with and without Impaired Renal Function

Introduction: Several randomised controlled trials have demonstrated better outcomes with primary percutaneous coronary intervention (PCI) over fibrinolytic therapy in the treatment of patients with ST-segment elevation myocardial infarction (STEMI) and normal renal function. Whether this benefit extends to patients with impaired renal function is uncertain. Materials and Methods: We studied 1672 patients with STEMI within 12 hours of symptom onset who were admitted to 2 major public hospitals in Singapore from 2000 to 2002. All patients received either upfront fibrinolytic or PCI as determined by the attending cardiologist. Serum creatinine was measured on admission and the glomerular filtration rate (GFR) was determined using the Modification of Diet in Renal Disease equation. The impact of reperfusion strategy on 30-ay mortality was then determined for patients with GFR ≥60 mL min-¹ 1.73 m-² and GFR <60 mL min-¹ 1.73 m-². Results: The mean age was 56 ± 12 years (85% male) and mean GFR was 81 ± 30 mL min-¹ 1.73 m-². Unadjusted 30-day mortality rates for fibrinolytic-treated vs primary PCI-treated patients were 29.4% vs 17.9%, P <0.05, in the impaired renal function group and 5.4% vs 3.1%, P <0.05, in the normal renal function group. After adjusting for covariates, primary PCI was associated with a significantly lower mortality in the normal renal function group [odds ratio (OR), 0.41; 95% confidence interval (CI), 0.19-0.89] but not in the impaired renal function group [OR, 0.70; 95% CI, 0.31-1.60]. Conclusions: Primary PCI was associated with improved 30-day survival among patients with normal renal function but not among those with impaired renal function. Randomised trials are needed to study the relative efficacy of both reperfusion strategies in patients with impaired renal function. Key words: Acute coronary syndrome, Fibrinolysis, Kidney disease, Primary angioplasty

Comparison of different antithrombotic regimens for patients with atrial fibrillation undergoing drug-eluting stent implantation

BACKGROUND

The optimal antithrombotic strategy for patients with atrial fibrillation (AF) undergoing drug-eluting stent (DES) implantation is unknown.

METHODS AND RESULTS

The 622 consecutive AF patients undergoing DES implantation were prospectively enrolled. Among them, 142 patients (TT group) continued triple antithrombotic therapy comprising aspirin, clopidogrel and warfarin after discharge; 355 patients (DT group) had dual antiplatelet therapy; 125 patients (WS group) were discharged with warfarin and a single antiplatelet agent. Target INR was set as 1.8-2.5 and was regularly monitored after discharge. The TT group had a significant reduction in stroke and major adverse cardiac and cerebral events (MACCE) (8.8% vs 20.1% vs 14.9%, P=0.010) as compared with either the DT or WS group. In the Cox regression analysis, administration with warfarin (hazard ratio (HR) 0.49; 95% confidence interval (CI) 0.31-0.77; P=0.002) and baseline CHADS(2) score >or=2 (HR 2.09; 95%CI 1.27-3.45; P=0.004) were independent predictors of MACCE. Importantly, the incidence of major bleeding was comparable among 3 groups (2.9% vs 1.8% vs 2.5%, P=0.725), although the overall bleeding rate was increased in the TT group. Kaplan-Meier analysis indicated that the TT group was associated with the best net clinical outcome.

CONCLUSIONS

The cardiovascular benefits of triple antithrombotic therapy were confirmed by reducing the MACCE rate, and its major bleeding risk might be acceptable if the INR is closely monitored.

Risk factors for consequent kidney impairment and differential impact of liver transplantation on renal function

BACKGROUND

Chronic kidney disease (CKD) develops frequently after liver transplantation (LTx), and it is important to identify and correct risk factors that negatively affect kidney function. Risk factors have not been well evaluated in Asian countries where hepatitis B virus (HBV) infection is a dominant cause.

METHODS

Four hundred thirty-one Korean recipients who underwent LTx between 1997 and 2008 were analysed. CKD was defined as a sustained decrease in estimated glomerular filtration rate (eGFR) of <60 (mL/min/1.73 m(2)) for at least three consecutive months using an abbreviated Modification in Renal Disease (MDRD) formula.

RESULTS

Eighty percent of the patients had HBV-related underlying diseases. The recipients whose pretransplant eGFR had been low (<30 mL/min/1.73 m(2)) improved their renal function after LTx, but significant functional decline occurred in recipients whose pretransplant eGFR was high (>or=60 mL/min/1.73 m(2)). A multivariate Cox regression analysis revealed that the overall risk of CKD development (eGFR < 60 mL/min/1.73 m(2)) was associated with old age of recipients, cyclosporine, posttransplant acute renal failure (ARF), cause [calcineurin inhibitor (CNI) nephrotoxicity] and severity of posttransplant ARF, low pretransplant eGFR, pretransplant hepatorenal syndrome, pretransplant proteinuria, high Child-Pugh score and high Model for End-Stage Renal Disease (MELD) score. Especially in recipients whose pre-operative eGFR was high (>or=60 mL/min/1.73 m(2)), rapid progression of kidney disease was associated with high tacrolimus level, non-HBV disease, posttransplant ARF, cause (CNI nephrotoxicity) and severity of posttransplant ARF and Child-Pugh score. CNI toxicity and focal segmental sclerosis, but not immune-complex disease, were revealed as significant contributors to CKD after LTx in HBV recipients.

CONCLUSION

Judicious use of CNIs should be applied to liver recipients to prevent kidney dysfunction.

Wave reflection and arterial stiffness in the prediction of 15-year all-cause and cardiovascular mortalities: a community-based study

The value of increased arterial wave reflection, usually assessed by the transit time-dependent augmentation index and augmented pressure (Pa), in the prediction of cardiovascular events may have been underestimated. We investigated whether the transit time-independent measures of reflected wave magnitude predict cardiovascular outcomes independent of arterial stiffness indexed by carotid-femoral pulse wave velocity. A total of 1272 participants (47% women; mean age: 52+/-13 years; range: 30 to 79 years) from a community-based survey were studied. Carotid pressure waveforms derived by tonometry were decomposed into their forward wave amplitudes, backward wave amplitudes (Pb), and a reflection index (=[Pb/(forward wave amplitude+Pb)]), in addition to augmentation index, Pa, and reflected wave transit time. During a median follow-up of 15 years, 225 deaths occurred (17.6%), including 64 cardiovascular origins (5%). In univariate Cox proportional hazard regression analysis, pulse wave velocity, Pa, and Pb predicted all-cause and cardiovascular mortality in both men and women, whereas augmentation index, reflected wave transit time, and reflection index were predictive only in men. In multivariate analysis accounting for age, height, and heart rate, Pb predicted cardiovascular mortality in both men and women, whereas Pa was predictive only in men. Per 1-SD increment (6 mm Hg), Pb predicted 15-year cardiovascular mortality independent of brachial but not central pressure, pulse wave velocity, augmentation index, Pa, and conventional cardiovascular risk factors with hazard ratios of approximately 1.60 (all P<0.05). In conclusion, Pb, a transit time-independent measure of reflected wave magnitude, predicted long-term cardiovascular mortality in men and women independent of arterial stiffness.

Study Protocol--accurate assessment of kidney function in Indigenous Australians: aims and methods of the eGFR study

BACKGROUND

There is an overwhelming burden of cardiovascular disease, type 2 diabetes and chronic kidney disease among Indigenous Australians. In this high risk population, it is vital that we are able to measure accurately kidney function. Glomerular filtration rate is the best overall marker of kidney function. However, differences in body build and body composition between Indigenous and non-Indigenous Australians suggest that creatinine-based estimates of glomerular filtration rate derived for European populations may not be appropriate for Indigenous Australians. The burden of kidney disease is borne disproportionately by Indigenous Australians in central and northern Australia, and there is significant heterogeneity in body build and composition within and amongst these groups. This heterogeneity might differentially affect the accuracy of estimation of glomerular filtration rate between different Indigenous groups. By assessing kidney function in Indigenous Australians from Northern Queensland, Northern Territory and Western Australia, we aim to determine a validated and practical measure of glomerular filtration rate suitable for use in all Indigenous Australians.

METHODS/DESIGN

A cross-sectional study of Indigenous Australian adults (target n = 600, 50% male) across 4 sites: Top End, Northern Territory; Central Australia; Far North Queensland and Western Australia. The reference measure of glomerular filtration rate was the plasma disappearance rate of iohexol over 4 hours. We will compare the accuracy of the following glomerular filtration rate measures with the reference measure: Modification of Diet in Renal Disease 4-variable formula, Chronic Kidney Disease Epidemiology Collaboration equation, Cockcroft-Gault formula and cystatin C- derived estimates. Detailed assessment of body build and composition was performed using anthropometric measurements, skinfold thicknesses, bioelectrical impedance and a sub-study used dual-energy X-ray absorptiometry. A questionnaire was performed for socio-economic status and medical history.

DISCUSSION

We have successfully managed several operational challenges within this multi-centre complex clinical research project performed across remote North, Western and Central Australia. It seems unlikely that a single correction factor (similar to that for African-Americans) to the equation for estimated glomerular filtration rate will prove appropriate or practical for Indigenous Australians. However, it may be that a modification of the equation in Indigenous Australians would be to include a measure of fat-free mass.

Decreased kidney function of unknown cause in Nicaragua: a community-based survey

BACKGROUND

End-stage kidney disease overwhelms health services in Central America. We determined prevalences of decreased kidney function in distinct populations in the most affected region of Nicaragua.

STUDY DESIGN

Cross-sectional survey.

SETTING & PARTICIPANTS

Total populations aged 20-60 years of 5 villages in Northwest Nicaragua: mining/subsistence farming (elevation, 100-300 m above sea level), banana/sugarcane (100-300 m), fishing (0-100 m), services (0-100 m), and coffee (200-675 m); 479 men and 617 women (83% response).

PREDICTOR OR FACTOR

Village; participant sex, age, and occupation; conventional chronic kidney disease risk factors.

OUTCOMES

Serum creatinine (SCr) values greater than laboratory reference range for sex, estimated glomerular filtration rate <60 mL/min/1.73 m(2), proteinuria stratified in the low (dipstick protein excretion, 30-300 mg/dL) and high (>300 mg/dL) range.

RESULTS

Prevalences of abnormal SCr levels: 18% (of all men) and 5% (of all women); in the mining/subsistence farming village, 26% and 7%; banana/sugarcane, 22% and 6%; fishing, 13% and 4%; services, 0% and 1%; and coffee, 7% and 0%. Prevalences of estimated glomerular filtration rate <60 mL/min/1.73 m(2): 14% (of all men) and 3% (of all women); in the listed villages, 19% and 5%, 17% and 4%, 10% and 2%, 0% and 0%, and 7% and 0%, respectively. Proteinuria, predominantly in the low range, affected 14% and 11% of all men and women without marked differences between villages. By occupation, abnormal SCr levels occurred in 31% and 24% of male and female agricultural workers at 100-300 m above sea level, but not at higher altitudes, and also was high in male artisans (43%), construction workers (15%), and miners (14%). In logistic regression models, for the banana/sugarcane and mining/subsistence farming villages, high blood pressure and age were significant predictors of abnormal SCr levels in men, and for mining/subsistence farming, age in women.

LIMITATIONS

Causality is not addressed.

CONCLUSIONS

In some Nicaraguan villages and population segments, men in particular show a high prevalence of decreased kidney function of unknown origin, possibly environmental or occupational.

Metabolic syndrome and the development of chronic kidney disease among 118 924 non-diabetic Taiwanese in a retrospective cohort

AIM

Metabolic syndrome (MetS) is a common risk factor for cardiovascular and chronic kidney disease (CKD) in Western populations; however, no prospective studies have examined MetS as a risk factor for CKD in Chinese adults.

METHODS

The incidence of CKD and the prospective link between MetS (defined by two criteria: modified Adult Treatment Panel III (ATP-III) and the International Diabetes Federation (IDF)) and CKD among 118,924 Taiwanese participants without baseline diabetes, aged 20-74 years with a mean 3.7 years follow up, was examined. CKD was measured by using estimated glomerular filtration rate or dipstick proteinuria (1+). The association between MetS or combination patterns of MetS abnormalities and CKD was evaluated using Cox models with adjustment for confounders.

RESULTS

The incidence of CKD was 288/10,000 person-years (95% confidence interval (CI), 283-293). The findings showed that central obesity (OB), high blood pressure (BP) and high triglyceride were considered to be the major metabolic events in the study cohort. Incidences and hazard ratios (HR) on CKD had evidently increasing trends with the number of MetS components. The multivariable-adjusted HR for CKD associated with ATP-III-MetS was 1.30 (95% CI, 1.24-1.36). Equivalent HR for IDF-MetS were 1.37 (95% CI, 1.30-1.44). The associations were still observed when analyzing by stratifying incident diabetes and adjusting hypertension status.

CONCLUSION

MetS induces an increased risk for CKD independent of baseline confounding factors and subsequent incident diabetes modified the associations lightly. The mechanism through which MetS may cause CKD in this population likely is the development of multiple metabolic pathogenic processes together.

Chronic kidney disease, all-cause mortality and cardiovascular mortality among Chinese patients with established cardiovascular disease

AIM

This study was conducted to investigate the role of chronic kidney disease (CKD) in 1-year all cause mortality and cardiovascular mortality among Chinese patients who were at least 50 years old and had a history of coronary artery disease (CAD), stroke, or peripheral vascular disease (PAD), or with two or more cardiovascular risks.

METHODS

Of 3,732 hospitalized patients enrolled, 3,423 patients (91.7%) with complete data were eligible for 1-year follow-up. CKD was defined as an estimated glomerular filtration rate (eGFR) of <60 mL/min/1.73 m(2).

RESULTS

1,166 (34.1%) were diagnosed with CKD. Most cases were unrecognized. Patients having an eGFR of <30 mL/min/1.73 m(2) were less likely to be prescribed beta-blockers, statins, or aspirin (all p<0.001). A powerful relationship was observed between the severity of renal dysfunction and all causes of death or cardiovascular death. Adjusted for other covariates, the hazard ratio (HR) for all causes of death and for cardiovascular death among patients with an eGFR of 30-45 mL/min/1.73 m(2) was 1.70 (95% CI, 1.18-2.45) and 1.85 (95% CI, 1.12-3.01) as compared with 2.93 (95% CI, 1.96-4.38) and 3.47 (95% CI, 1.91-6.31) for patients with an eGFR of <30 mL/min/1.73 m(2).

CONCLUSIONS

One third of Chinese patients at high risk for atherosclerotic events were diagnosed with CKD. Most of these cases were unrecognized and undertreated. An eGFR of <45 mL/min/1.73 m(2) was an independent predictor of all causes of death and of cardiovascular death.

White blood cell count and renin-angiotensin system inhibitors for the risk of cancer in type 2 diabetes

BACKGROUND

High white blood cell (WBC) predicted cancer-associated mortality and renin-angiotensin system (RAS) inhibitors have immunomodulating effects. We hypothesize that RAS inhibitors may reduce cancer risk associated with high WBC in type 2 diabetes mellitus (T2DM).

METHODS

A prospective cohort of 4570 Chinese T2DM patients, free of cancer at enrolment, were analyzed. Biological interaction between WBC groups and use of RAS inhibitors was estimated using relative excess risk due to interaction (RERI), attributable proportion due to interaction (AP) and synergy index (S). RERI>0, AP>0 or S>1 indicates biological interaction.

RESULTS

During 4.89 years of follow-up, 205 (4.49%) patients developed cancer. WBC > or = 8.2 x 10(9) counts/L plus non-use of RAS inhibitors was associated with elevated cancer risks in multivariable models. The RERI and AP for interaction between WBC > or = 8.2 x 10(9) counts/L and non-use of RAS inhibitors were, respectively, 1.26 (95% CI: 0.22-2.31) and 0.50 (0.23-0.78). In patients with WBC > or = 8.2 x 10(9) counts/L, use of RAS inhibitors was associated with 64% (31-81%) cancer risk reduction in multivariable analysis.

CONCLUSIONS

In T2DM, increased WBC predicts cancer while use of RAS inhibitors may reduce cancer risks associated with high WBC count.

Low dietary sodium intake increases the death risk in peritoneal dialysis

BACKGROUND AND OBJECTIVES

To explore the correlation between dietary sodium intake and cardiovascular and overall mortality, and then determine whether this correlation can be explained by protein and energy intake paralleled with sodium intake in dialysis patients.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

This single-center retrospective cohort study enrolled 305 incident patients who started peritoneal dialysis in our unit from July 2002 to February 2007. All patients were followed until death or until being censored in February 2008. Demographic data were collected at baseline. Biochemical, dietary, and nutrition data were examined at baseline and thereafter at regular intervals to calculate the average values throughout the study.

RESULTS

Participants with the highest average sodium intake were more likely to be younger, male, and overweight. Patients in the high tertile of average sodium intake had higher albumin, prealbumin, and lean body mass levels, and more nutrient intakes paralleling with sodium intake. Low average sodium intake independently predicted the increased risk for overall and cardiovascular death after adjusting for recognized confounders. Further adjustment for dietary protein, energy, and other nutrient intakes individually had minimal impact on the association between average sodium intake and overall death, with hazard ratios varying between 0.35 and 0.44, and cardiovascular death, with hazard ratios varying between 0.06 and 0.11.

CONCLUSIONS

This study revealed that low dietary sodium intake independently predicts the high overall and cardiovascular mortality in dialysis patients. This correlation could not be entirely explained by deficient protein and energy intake.

The choice of estimating equations for glomerular filtration rate significantly affects the prevalence of chronic kidney disease in a multi-ethnic population during health screening

BACKGROUND

Patients present to the National University Hospital of Singapore and select one of several health screening packages after counselling. The prevalence of chronic kidney disease (CKD) in this population when different glomerular filtration rate (GFR) estimating equations are used has not been examined.

METHODS

Demographic data and urinalyses of patients from 2000 to 2005 were extracted from laboratory computer databases and analysed. CKD was classified into stages according to the US National Kidney Foundation guidelines by eGFR (mL/min per 1.73 m(2)) using the four-variable Modification of Diet in Renal Disease equation. GFR of ethnic Chinese was also estimated using Ma's equation 8 (cGFR). Stage 1 and normal (eGFR or cGFR > 90) was discriminated by urinary microscopy or dipstick for proteinuria, albuminuria, hematuria or leukocyturia.

RESULTS

There were 3979 screenings (55.9% males, 61.9% Chinese). Means: age = 47.0 +/- 12.3 years, creatinine = 80.1 +/- 26.5 micromol/L, eGFR = 89.6 +/- 19.7, cGFR = 110.8 +/- 23.8 and (eGFR + cGFR) = 102.5 +/- 24.9. By eGFR in all patients, the prevalence of CKD was 45.7%, 50.6%, 3.3%, 0.3% and 0.08% for stages normal or 1, 2, 3, 4 and 5, respectively. For Chinese patients only, eGFR and cGFR resulted in a different distribution (eGFR%/cGFR%): 24.9/50.5, 15.2/29.3, 56.8/19.7, 3/0.8, 0.2/0.2, 0/0 for stages 'Normal', 1, 2, 3, 4 and 5, respectively (P < 0.001).

CONCLUSION

The prevalence of moderate to severe CKD (stage 3 to 5) in patients presenting for health screening in Singapore was 3.7%. Notably, the prevalence of mild to moderate CKD (stages 1, 2 and 3) in Chinese patients was affected significantly by the choice of GFR estimating equation.

Carotid endarterectomy benefits patients with CKD and symptomatic high-grade stenosis

Endarterectomy is generally recommended for symptomatic high-grade (70 to 99%) stenosis of the internal carotid artery, but whether this procedure is beneficial among patients with chronic kidney disease (CKD) is unknown. In this re-analysis of data from the North American Symptomatic Carotid Endarterectomy Trial, we included patients with symptomatic stenosis and either stage 3 CKD (n = 524) or preserved kidney function (n = 966; estimated GFR > or = 60). For medically treated patients with high-grade stenosis, risk for ipsilateral stroke at 2 yr was significantly higher in patients with CKD than in those with preserved renal function (31.6 versus 19.3%; P = 0.042); carotid endarterectomy significantly reduced this risk by 82 and 51%, respectively. To prevent one ipsilateral stroke, the number needed to treat by endarterectomy was four for patients with CKD and 10 for patients with preserved renal function. Compared with patients with preserved renal function, those with CKD had similar rates of perioperative stroke and death but higher rates of cardiac events. In conclusion, patients with stage 3 CKD and symptomatic high-grade carotid stenosis gain a large benefit in stroke risk reduction after endarterectomy.

Detection and prevention of chronic kidney disease in Indonesia: initial community screening

AIM

This survey evaluated the prevalence of chronic kidney disease (CKD if estimated glomerular filtration rate (eGFR) <60 mL/min per 1.73 m(2)) and its risk factors amongst subjects from urban and semi-urban areas.

METHODS

History of hypertension, diabetes mellitus, kidney disease, cardio- and cerebrovascular diseases of subjects and their families was recorded. Blood pressure was determined as the mean of three readings in the sitting position and hypertension classified according to the Joint National Committee VII. Urinalysis was assessed using Combi 10R dipstick test. Random blood glucose and serum creatinine were measured in subjects with either hypertension, proteinuria, glycosuria and/or a history of diabetes. eGFR was calculated according Cockcroft-Gault (CG) adjusted by body surface area (BSA), Modification of Diet in Renal Disease (MDRD) and Chinese MDRD equations.

RESULTS

Of 9412 subjects recruited, 64.1% were female. Persistent proteinuria was found in almost 3%. Systolic and diastolic hypertension was found in 10%, isolated systolic hypertension in 4.8% and isolated diastolic hypertension in 4.6%. CKD was found in 12.5% (CG), 8.6% (MDRD) or 7.5% (Chinese MDRD) of subjects with either hypertension, proteinuria and/or diabetes. Proteinuria, systolic blood pressure and a history of diabetes mellitus were independent predictors of impaired eGFR. Obesity and smoking history were found in 32.5% and 19.8%, respectively.

CONCLUSION

The present study showed a high prevalence of CKD in representative urban and semi-urban areas and argues for screening and treatment of all Indonesians, particularly those at an increased risk of CKD.

Obesity and metabolic syndrome-related chronic kidney disease in nondiabetic, nonhypertensive adults

Metabolic syndrome (MS) is associated with chronic kidney disease (CKD). The objective of this study is to examine the association between obesity and MS-related CKD in nondiabetic, nonhypertensive Korean adults. Korea National Health and Nutrition Examination Survey III data from 3771 nondiabetic, nonhypertensive Koreans were analyzed. Metabolic syndrome was defined according to the National Cholesterol Education Program-Adult Treatment Panel III, and CKD was diagnosed at an estimated glomerular filtration rate less than 60 mL/(min 1.73 m(2)). The crude and multivariate-adjusted odds ratios (ORs) of CKD associated with MS and its individual components were calculated using logistic regression models in a study population stratified by obesity. The prevalence of MS and CKD was 13.4% and 3.2%, respectively. The association between MS and CKD was significant in obese (OR, 2.91; 95% confidence interval [CI] = 1.34-6.34), but not nonobese (OR, 1.38; 95% CI = 0.60-3.17), subjects. In obese subjects, impaired fasting glucose (OR, 2.47; 95% CI = 1.10-5.57) and high triglyceride levels (OR, 2.42; 95% CI = 1.01-5.83) were risk factors for CKD, whereas no components were significantly associated with CKD in nonobese subjects. Our findings suggest that even in nondiabetic, nonhypertensive Korean adults, early detection and prevention of CKD in obese subjects with MS are critical.

Analysis of multidisciplinary care models and interface with primary care in management of chronic kidney disease

Public policy efforts and education have led to an increased appreciation of the prevalence of chronic kidney disease (CKD) in general outpatient populations. The complexity of the care of individuals with established CKD has led to the development of multidisciplinary care models, which have been shown to improve the clinical outcomes of those with CKD. The interface between specialty and primary care in various systems remains necessary and desired, albeit a continuing challenge. This overview reviews various models of specialty care for CKD patients, including those that emphasize multidisciplinary team approaches, and highlight the essential role(s) of primary care physicians. Importantly, there is a need for improved definition of CKD populations and individuals, review and refinement of proposed care pathways, and the need to define essential elements of care for the patient. Models of care often are not subject to the same rigor that other interventions applied to this population are; nonetheless, we offer here a framework for establishing and evaluating care models for the CKD populations at various stages of disease and with various comorbidities.

Gout: an independent risk factor for all-cause and cardiovascular mortality

OBJECTIVE

The relation of gout and hyperuricaemia to cardiovascular diseases has been well documented. This study investigates the survival impact of both gout and hyperuricaemia.

METHODS

The subjects of this study comprised participants of a health screening programme conducted by the Chang Gung Memorial Hospital in Taiwan from 2000 to 2006. The status and causes of death were ascertained by the Taiwan National Death Registry 2000-07. Cox proportional hazard model was performed to examine the association.

RESULTS

Among 61 527 subjects, 1383 deaths (198 cardiovascular deaths) were identified, corresponding to a crude mortality rate of 4.86 deaths per 1000 person-years. Crude mortality rates were 4.50, 5.61 and 10.46 deaths per 1000 person-years for subjects with normouricaemia, hyperuricaemia and gout, respectively. Compared with subjects with normouricaemia, the hazard ratios (HRs) of all-cause mortality were 1.46 (95% CI 1.12, 1.91) for individuals with gout and 1.07 (95% CI 0.94, 1.22) for those with hyperuricaemia, respectively, after adjustments were made for age, sex, component number of metabolic syndrome and proteinuria. The adjusted HRs of cardiovascular mortality were 1.97 (95% CI 1.08, 3.59) for individuals with gout and 1.08 (95% CI 0.78, 1.51) for those with hyperuricaemia. Moreover, the risk of all-cause or cardiovascular mortality for gout remained unchanged when limiting the data to those with an estimated glomerular filtration of >60 ml/min/1.73 m(2).

CONCLUSION

This study demonstrates a link of gout, not hyperuricaemia, with a higher risk of death from all causes and cardiovascular diseases.

Glomerular filtration rate measurement and prediction equations

Chronic kidney disease (CKD) is defined as the presence of kidney damage or a glomerular filtration rate (GFR) <60 mL/min/1.73 m(2) for three or more months. Measurement of serum creatinine is the most commonly used method to evaluated kidney function, but it must be included in formulas to estimate GFR, adjusting for age, gender and ethnicity, such as the Modification of Diet in Renal Disease (MDRD) study equation. The performance of this equation is acceptable for patients with CKD but appears to under-estimate GFR in populations with unknown kidney status. A new formula has been developed recently. The Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation appears to perform better than the MDRD equation. Cystatin C has been widely evaluated as a marker for GFR and seems to be more sensitive than creatinine. The aim of this review is to discuss the recommendations for detecting CKD, emphasizing the characteristics and limitations of GFR estimating equations and pitfalls in the evaluation of urinary albumin excretion.