Background and objectives Uremic pruritus in patients on hemodialysis is associated with depression, lower quality of life, and mortality. We studied the prevalence, awareness, and treatment of pruritus to assess how well this important condition is currently managed internationally. Design, setting, participants, & measurements Data from 35,452 patients on hemodialysis in up to 17 countries from the Dialysis Outcomes and Practice Patterns Study were analyzed to describe pruritus prevalence from 1996 to 2015. Data from 6256 patients and 268 medical directors in 17 countries in 2012–2015 were analyzed to describe predictors, effects, medical directors’ awareness, and treatment of pruritus. Results Patients very much or extremely bothered by itching declined from 28% in 1996 to 18% in 2015. In 2012–2015, among patients nearly always or always bothered by itching, pruritus had a major effect on work and social life; 18% used no treatment for pruritus, and 17% did not report itching to health care staff. In total, 69% of medical directors underestimated the prevalence of pruritus in their unit. Managing high serum phosphorus and low Kt/V was ranked as the most important intervention, but no relationship was found between these factors and pruritus; 57% of medical directors used oral antihistamines for first-line chronic treatment of pruritus. Gabapentin was used by 45% as first-, second-, or third-line treatment. Nalfurafine was only used in Japan. Conclusions The prevalence of pruritus in people on hemodialysis is decreasing but remains underestimated. Large numbers of patients on hemodialysis with severe pruritus do not receive treatment. There is wide variation in the use of unlicensed medications for the treatment of pruritus. These data provide a benchmark for initiatives to improve the management of uremic pruritus. Multimedia This article contains multimedia at https://vimeo.com/49458473 This article contains multimedia at vimeo.com/49455976

Background and objectives Elevated parathyroid hormone levels may be associated with adverse clinical outcomes in patients on dialysis. After the introduction of practice guidelines suggesting higher parathyroid hormone targets than those previously recommended, changes in parathyroid hormone levels and treatment regimens over time have not been well documented. Design, setting, participants, & measurements Using data from the international Dialysis Outcomes and Practice Patterns Study, trends in parathyroid hormone levels and secondary hyperparathyroidism therapies over the past 15 years and the associations between parathyroid hormone and clinical outcomes are reported; 35,655 participants from the Dialysis Outcomes and Practice Patterns Study phases 1–4 (1996–2011) were included. Results Median parathyroid hormone increased from phase 1 to phase 4 in all regions except for Japan, where it remained stable. Prescriptions of intravenous vitamin D analogs and cinacalcet increased and parathyroidectomy rates decreased in all regions over time. Compared with 150–300 pg/ml, in adjusted models, all-cause mortality risk was higher for parathyroid hormone=301–450 (hazard ratio, 1.09; 95% confidence interval, 1.01 to 1.18) and >600 pg/ml (hazard ratio, 1.23; 95% confidence interval, 1.12 to 1.34). Parathyroid hormone >600 pg/ml was also associated with higher risk of cardiovascular mortality as well as all-cause and cardiovascular hospitalizations. In a subgroup analysis of 5387 patients not receiving vitamin D analogs or cinacalcet and with no prior parathyroidectomy, very low parathyroid hormone (<50 pg/ml) was associated with mortality (hazard ratio, 1.25; 95% confidence interval, 1.04 to 1.51). Conclusions In a large international sample of patients on hemodialysis, parathyroid hormone levels increased in most countries, and secondary hyperparathyroidism treatments changed over time. Very low and very high parathyroid hormone levels were associated with adverse outcomes. In the absence of definitive evidence in support of a specific parathyroid hormone target, there is an urgent need for additional research to inform clinical practice.

A comprehensive analysis of sex-specific differences in the characteristics, treatment, and outcomes of individuals with end-stage renal disease undergoing dialysis might reveal treatment inequalities and targets to improve sex-specific patient care. Here we describe hemodialysis prevalence and patient characteristics by sex, compare the adult male-to-female mortality rate with data from the general population, and evaluate sex interactions with mortality. We assessed the Human Mortality Database and 206,374 patients receiving hemodialysis from 12 countries (Australia, Belgium, Canada, France, Germany, Italy, Japan, New Zealand, Spain, Sweden, the UK, and the US) participating in the international, prospective Dialysis Outcomes and Practice Patterns Study (DOPPS) between June 1996 and March 2012. Among 35,964 sampled DOPPS patients with full data collection, we studied patient characteristics (descriptively) and mortality (via Cox regression) by sex. In all age groups, more men than women were on hemodialysis (59% versus 41% overall), with large differences observed between countries. The average estimated glomerular filtration rate at hemodialysis initiation was higher in men than women. The male-to-female mortality rate ratio in the general population varied from 1.5 to 2.6 for age groups <75 y, but in hemodialysis patients was close to one. Compared to women, men were younger (mean = 61.9±standard deviation 14.6 versus 63.1±14.5 y), were less frequently obese, were more frequently married and recipients of a kidney transplant, more frequently had coronary artery disease, and were less frequently depressed. Interaction analyses showed that the mortality risk associated with several comorbidities and hemodialysis catheter use was lower for men (hazard ratio [HR] = 1.11) than women (HR = 1.33, interaction p<0.001). This study is limited by its inability to establish causality for the observed sex-specific differences and does not provide information about patients not treated with dialysis or dying prior to a planned start of dialysis. Women's survival advantage was markedly diminished in hemodialysis patients. The finding that fewer women than men were being treated with dialysis for end-stage renal disease merits detailed further study, as the large discrepancies in sex-specific hemodialysis prevalence by country and age group are likely explained by factors beyond biology. Modifiable variables, such as catheter use, showing significant sex interactions suggest interventional targeting. Please see later in the article for the Editors' Summary Throughout life, the kidneys filter waste products (from the normal breakdown of tissues and from food) and excess water from the blood to make urine. Chronic kidney disease—an increasingly common condition globally—gradually destroys the kidney's filtration units (the nephrons). As the nephrons stop working, the rate at which the blood is filtered (the glomerular filtration rate) decreases, and waste products build up in the blood, eventually leading to life-threatening end-stage kidney (renal) disease. Symptoms of chronic kidney disease, which rarely occur until the disease is advanced, include tiredness, swollen feet and ankles, and frequent urination, particularly at night. Chronic kidney disease cannot be cured, but its progression can be slowed by controlling diabetes and other conditions that contribute to its development. End-stage kidney disease is treated by regular hemodialysis (a process in which blood is cleaned by passing it through a filtration machine) or by kidney transplantation. Like many other long-term conditions, the prevalence (the proportion of the population that has a specific disease) of chronic kidney disease and of end-stage renal disease, and treatment outcomes for these conditions, may differ between men and women. Some of these sex-specific differences may arise because of sex-specific differences in normal biological functions. Other sex-specific differences may be related to sex-specific differences in patient care or in patient awareness of chronic kidney disease. A comprehensive analysis of sex-specific differences among individuals with end-stage renal disease might identify both treatment inequalities and ways to improve sex-specific care. Here, in the Dialysis Outcomes and Practice Patterns Study (DOPPS), the researchers investigate sex-specific differences in the prevalence and practices of hemodialysis and in the characteristics of patients undergoing hemodialysis, and investigate the adult male-to-female mortality (death) rate among patients undergoing hemodialysis. The DOPPS is a prospective cohort study that is investigating the characteristics, treatment, and outcomes of adult patients undergoing hemodialysis in representative facilities in 19 countries (12 countries were available for analysis at the time of the current study). To investigate sex-specific differences in hemodialysis prevalence, the researchers compared data from the Human Mortality Database, which provides detailed population and mortality data for 37 countries, with data collected by the DOPPS. Forty-one percent of DOPPS patients were women, compared to 52% of the general population in 12 of the DOPPS countries. Next, the researchers used data collected from a randomly selected subgroup of patients to examine sex-specific differences in patient characteristics and mortality. The average estimated glomerular filtration rate at hemodialysis initiation was higher in men than women. Moreover, men were more frequently recipients of a kidney transplant than women. Notably, although in the general population in a given age group women were less likely to die than men, among hemodialysis patients, women were as likely to die as men. Finally, the researchers investigated which patient characteristics were associated with the largest sex-specific differences in mortality risk. The use of a hemodialysis catheter (a tube that is inserted into a patient's vein to transfer their blood into the hemodialysis machine) was associated with a lower mortality risk in men than in women. These findings show that, among patients treated with hemodialysis for end-stage renal disease, women differ from men in many ways. Although some of these sex-specific differences may be related to biology, others may be related to patient care and to patient awareness of chronic kidney disease. Because this is an observational study, these findings cannot prove that the reported differences in hemodialysis prevalence, treatment, and mortality are actually caused by being a man or a woman. Importantly, however, these findings suggest that hemodialysis may abolish the survival advantage that women have over men in the general population and that fewer women than men are being treated for end-stage-renal disease, even though chronic kidney disease is more common in women than in men. Finally, the finding that the use of hemodialysis catheters for access to veins is associated with a higher mortality risk among women than among men suggests that, where possible, women should be offered a surgical process called arteriovenous fistula placement, which is recommended for access to veins during long-term hemodialysis but which may, in the past, have been underused in women. Please access these websites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.1001750.

Summary Background and objectives Measurement of C-reactive protein (CRP) levels remains uncommon in North America, although it is now routine in many countries. Using Dialysis Outcomes and Practice Patterns Study data, our primary aim was to evaluate the value of CRP for predicting mortality when measured along with other common inflammatory biomarkers. Design, setting, participants, & measurements We studied 5061 prevalent hemodialysis patients from 2005 to 2008 in 140 facilities routinely measuring CRP in 10 countries. The association of CRP with mortality was evaluated using Cox regression. Prediction of 1-year mortality was assessed in logistic regression models with differing adjustment variables. Results Median baseline CRP was lower in Japan (1.0 mg/L) than other countries (6.0 mg/L). CRP was positively, monotonically associated with mortality. No threshold below which mortality rate leveled off was identified. In prediction models, CRP performance was comparable with albumin and exceeded ferritin and white blood cell (WBC) count based on measures of model discrimination (c-statistics, net reclassification improvement [NRI]) and global model fit (generalized R²). The primary analysis included age, gender, diabetes, catheter use, and the four inflammatory markers (omitting one at a time). Specifying NRI ≥5% as appropriate reclassification of predicted mortality risk, NRI for CRP was 12.8% compared with 10.3% for albumin, 0.8% for ferritin, and <0.1% for WBC. Conclusions These findings demonstrate the value of measuring CRP in addition to standard inflammatory biomarkers to improve mortality prediction in hemodialysis patients. Future studies are indicated to identify interventions that lower CRP and to identify whether they improve clinical outcomes.