Rationale and population-based prospective cohort protocol for the disadvantaged populations at risk of decline in eGFR (CO-DEGREE).

INTRODUCTION: A recently recognised form of chronic kidney disease (CKD) of unknown origin (CKDu) is afflicting communities, mostly in rural areas in several regions of the world. Prevalence studies are being conducted in a number of countries, using a standardised protocol, to estimate the distribution of estimated glomerular filtration rate (eGFR), and thus identify communities with a high prevalence of reduced glomerular filtration rate (GFR). In this paper, we propose a standardised minimum protocol for cohort studies in high-risk communities aimed at investigating the incidence of, and risk factors for, early kidney dysfunction. METHODS AND ANALYSIS: This generic cohort protocol provides the information to establish a prospective population-based cohort study in low-income settings with a high prevalence of CKDu. This involves a baseline survey that included key elements from the DEGREE survey (eg, using the previously published DEGREE methodology) of a population-representative sample, and subsequent follow-up visits in young adults (without a pre-existing diagnosis of CKD (eGFR<60 mL/min/1.73m2), proteinuria or risk factors for CKD at baseline) over several years. Each visit involves a core questionnaire, and collection and storage of biological samples. Local capacity to measure serum creatinine will be required so that immediate feedback on kidney function can be provided to participants. After completion of follow-up, repeat measures of creatinine should be conducted in a central laboratory, using reference standards traceable to isotope dilution mass spectrometry (IDMS) quality control material to quantify the main outcome of eGFR decline over time, alongside a description of the early evolution of disease and risk factors for eGFR decline. ETHICS AND DISSEMINATION: Ethical approval will be obtained by local researchers, and participants will provide informed consent before the study commences. Participants will typically receive feedback and advice on their laboratory results, and referral to a local health system where appropriate.

Temporal Trends and Factors Associated with Medication Prescription Patterns in Peritoneal Dialysis Patients.

INTRODUCTION: Patients on peritoneal dialysis (PD) suffer from a high burden of comorbidities, which are managed with multiple medications. Determinants of prescription patterns are largely unknown in this population. This study assesses temporal changes and factors associated with medication prescription in a nationally representative population of patients on PD under the universal coverage healthcare system in Brazil. METHODS: Incident patients recruited in the Brazilian Peritoneal Dialysis Study (BRAZPD) from December 2004 to January 2011, stratified by prior hemodialysis (HD) treatment, were included in the analysis. Multivariable logistic regression was used to assess the association between medication prescription and socioeconomic factors. Yearly prevalent cross-sections were calculated to estimate prescription over time. RESULTS: Medication prescription was in general higher among patients who had previously received HD, compared with those who started renal replacement therapy (RRT) directly on PD. Prescription increased from baseline to 6 months of PD therapy, particularly in those who did not previously receive HD. After accounting for patient characteristics, significant associations were found between socioeconomic factors, geographic region, and medication prescription patterns. Finally, the prescription of all cardioprotective and anemia medications and phosphate binders increased significantly over time. CONCLUSION: In a PD population under universal coverage in a developing country, there was an increase in drug prescription during the first 6 months on PD, and a trend toward more liberal prescription of medications in later years. Independent from patient characteristics and comorbidities, socioeconomic factors influenced drug prescriptions that likely impact patient outcome, calling for public health action to decrease potential inequities in management of comorbidities in PD patients.

Differences in mortality among Mexican-American, Puerto Rican, and Cuban-American dialysis patients in the United States.

BACKGROUND: The Hispanic ethnic group is heterogeneous, with distinct genetic, cultural, and socioeconomic characteristics, but most prior studies of patients with end-stage renal disease focus on the overall Hispanic ethnic group without further granularity. We examined survival differences among Mexican-American, Puerto Rican, and Cuban-American dialysis patients in the United States. STUDY DESIGN: Prospective observational study. SETTING & PARTICIPANTS: Data from individuals randomly selected for the End-Stage Renal Disease Clinical Performance Measures Project (2001 to 2005) were examined. Mexican-American (n = 2,742), Puerto Rican (n = 838), Cuban-American (n = 145), and Hispanic-other dialysis patients (n = 942) were compared with each other and with non-Hispanic (n = 33,076) dialysis patients in the United States. PREDICTORS: Patient characteristics of interest included ethnicity/race, comorbidities, and specific available laboratory values. OUTCOMES: The major outcome of interest was mortality. RESULTS: In the fully adjusted multivariable model, 2-year mortality risk was significantly lower for the Mexican-American and Hispanic-other groups compared with non-Hispanics (adjusted hazard ratio, 0.79; 95% confidence interval, 0.73 to 0.85; adjusted hazard ratio, 0.81; 95% confidence interval, 0.71 to 0.92, respectively). Differences in 2-year mortality rates within the Hispanic ethnic groups were statistically significant (P = 0.004) and ranged from 21% lower mortality in Mexican Americans to 3% higher mortality in Puerto Ricans compared with non-Hispanics. LIMITATIONS: Include those inherent to an observational study, potential ethnic group misclassification, and small sample sizes for some Hispanic subgroups. CONCLUSION: Mexican-American and Hispanic-other dialysis patients have a survival advantage compared with non-Hispanics. Furthermore, Mexican Americans, Cuban Americans, and Hispanic others had a survival advantage compared with their Puerto Rican counterparts. Future research should continue to examine subgroups within Hispanic ethnicity to understand underlying reasons for observed differences that may be masked by examining the Hispanic ethnic group as only a single entity.

Lack of appetite in haemodialysis patients--associations with patient characteristics, indicators of nutritional status and outcomes in the international DOPPS.

BACKGROUND: Identification of haemodialysis patients with problems related to lack of appetite should help prevent adverse outcomes. We studied whether a single question about being bothered by lack of appetite within the prior 4 weeks is related to nutritional status, inflammation and risks of death and hospitalization. Additionally, we assessed associations of lack of appetite with depression, dialysis dose and length of haemodialysis. METHODS: This study is an analysis of baseline and longitudinal data from 14 406 patients enrolled in the Dialysis Outcomes and Practice Pattern Study. Cox regression was used to assess whether the degree (not, somewhat, moderately, very much, extremely) that patients were bothered by lack of appetite is an independent predictor of death and hospitalization. Logistic regression was used to identify baseline characteristics associated with being bothered by lack of appetite. RESULTS: The risk of death was more than 2-fold higher [relative risk (RR) = 2.23; 95% confidence interval (CI) = 1.90-2.62] and the risk of hospitalization 33% higher (RR = 1.33; 95% CI = 1.19-1.48) among patients extremely bothered, compared with not bothered, by lack of appetite. These associations followed a dose-response fashion and remained statistically significant after adjustments for 14 comorbidities. Depression, shorter haemodialysis session, hypoalbuminaemia, lower concentration of serum creatinine and normalized protein catabolic rate, lower body mass index and higher leucocyte and neutrophil counts were independently associated with higher odds of being bothered by lack of appetite. CONCLUSIONS: The data suggest that a single question about lack of appetite helps identify haemodialysis patients with poorer nutritional status, inflammation, depression and higher risks of hospitalization and death. The study calls attention to a possible beneficial effect of longer haemodialysis on appetite.