The aim of this study was to estimate the incidence of COVID-19 disease in the French national population of dialysis patients, their course of illness and to identify the risk factors associated with mortality. Our study included all patients on dialysis recorded in the French REIN Registry in April 2020. Clinical characteristics at last follow-up and the evolution of COVID-19 illness severity over time were recorded for diagnosed cases (either suspicious clinical symptoms, characteristic signs on the chest scan or a positive reverse transcription polymerase chain reaction) for SARS-CoV-2. A total of 1,621 infected patients were reported on the REIN registry from March 16th, 2020 to May 4th, 2020. Of these, 344 died. The prevalence of COVID-19 patients varied from less than 1% to 10% between regions. The probability of being a case was higher in males, patients with diabetes, those in need of assistance for transfer or treated at a self-care unit. Dialysis at home was associated with a lower probability of being infected as was being a smoker, a former smoker, having an active malignancy, or peripheral vascular disease. Mortality in diagnosed cases (21%) was associated with the same causes as in the general population. Higher age, hypoalbuminemia and the presence of an ischemic heart disease were statistically independently associated with a higher risk of death. Being treated at a selfcare unit was associated with a lower risk. Thus, our study showed a relatively low frequency of COVID-19 among dialysis patients contrary to what might have been assumed.

Between January 1, 1976, and December 31, 2002, histologic diagnosis of primary glomerular diseases (PGD) was made in 898 patients born and living at the time of diagnosis in a region of France, comprising 412,735 inhabitants, of whom 391,265 were aged from 10 to 85 years. The prevalence of PGD during a 75-year exposure to risk (10 to 85 years of age) was evaluated to 6.9 in 1000 (8.2 in 1000 males and 5.1 in 1000 females) during the 27-year period. The most common PGD was IgA nephropathy (IgAN) with a prevalence of 2.4 in 1000 (3.6 in 1000 males and 1.3 in 1000 females). The annual incidence of PGD was evaluated separately for two consecutive 10-years periods: period A (1976 to 1985), period B (1986 to 1995) and for one 7-year period: period C (1996 to 2002). Within each of these three periods, annual incidence of PGD was 89, 76, and 65 per million inhabitants. During this 27-year period, the annual incidences of membranoproliferative glomerulonephritis (GN) and membranous nephropathy were declining and the incidence of crescentic proliferative GN was strongly progressing, whereas annual incidence of nephrosis remained stable. The incidence of IgAN remained the same throughout the three periods: 28, 28, and 26 per million inhabitants. Whereas the incidence of IgAN was three- to fourfold higher in the adult aged from 20 to 59 years than in the elderly during the periods A (38 vs. 11 per million inhabitants) and B (37 vs. 12 per million inhabitants), the incidence became similar whatever age groups during the last period C (20 to 59 years, 25 per million inhabitants; 60 to 79 years, 27 per million inhabitants; and 80 years and over, 28 per million inhabitants. The stability of annual incidence according to period and age, which is demonstrated for the first time during the last period, provides a new evidence of a role for genetic factors in the pathogenesis of IgAN.

Between January 1, 1976 and December 31, 1990, histological diagnosis of primary glomerular diseases (PGD) was made in 480 patients born and living at the time of diagnosis in a region of France, comprising 410,664 inhabitants, of whom 390,574 were aged from 10 to 80 years. The prevalence of PGD during a 70 year exposure to risk (10 to 80 years of age) was evaluated to 5.7 in 1000 (7.6 in 1000 males and 3.8 in 1000 females). The most common PGD was IgA nephropathy with a prevalence of 1.9 in 1000 (3.3 in 1000 males, 1 in 1000 females). The annual incidence of the disease was evaluated separately for three consecutive five-year periods: period A (1976-80), period B (1981-85), and period C (1986-90). Within each of these three periods the number of patients with PGD was 179, 170 and 131, respectively, and annual incidence was 9.3, 8.8 and 6.7 in 100,000. The incidence of IgA nephropathy remained the same throughout the three periods: 2.6, 3.1 and 2.5 in 100,000. The incidence of membranoproliferative glomerulonephritis decreased from 1981 onward (0.9, 0.5 and 0.15 in 100,000), while that of membranous nephropathy increased slightly (1.2, 1.6 and 1.7 in 100,000). Acute streptococcal glomerulonephritis virtually disappeared during periods B and C. Lipoid nephrosis was less frequent in period C and idiopathic proliferative glomerulonephritis with crescents slightly increased (0.3, 0.4 and 0.6 in 100,000). There was no significant difference between the three periods regarding the incidence of other PGD.(ABSTRACT TRUNCATED AT 250 WORDS)

Dialysis patients exhibit an inverse, L- or U-shaped association between blood pressure and mortality risk, in contrast to the linear association in the general population. We prospectively studied 9333 hemodialysis patients in France, aiming to analyze associations between predialysis systolic, diastolic, and pulse pressure with all-cause mortality, cardiovascular mortality, and nonfatal cardiovascular endpoints for a median follow-up of 548 days. Blood pressure components were tested against outcomes in time-varying covariate linear and fractional polynomial Cox models. Changes throughout follow-up were analyzed with a joint model including both the time-varying covariate of sequential blood pressure and its slope over time. A U-shaped association of systolic blood pressure was found with all-cause mortality and of both systolic and diastolic blood pressure with cardiovascular mortality. There was an L-shaped association of diastolic blood pressure with all-cause mortality. The lowest hazard ratio of all-cause mortality was observed for a systolic blood pressure of 165 mm Hg, and of cardiovascular mortality for systolic/diastolic pressures of 157/90 mm Hg, substantially higher than currently recommended values for the general population. The 95% lower confidence interval was approximately 135/70 mm Hg. We found no significant correlation for either systolic, diastolic, or pulse pressure with myocardial infarction or nontraumatic amputations, but there were significant positive associations between systolic and pulse pressure with stroke (per 10-mm Hg increase: hazard ratios 1.15, 95% confidence interval 1.07 and 1.23; and 1.20, 1.11 and 1.31, respectively). Thus, whereas high pre-dialysis blood pressure is associated with stroke risk, low pre-dialysis blood pressure may be both harmful and a proxy for comorbid conditions leading to premature death.

Background Previous US studies have indicated that haemodialysis with ≥6-h sessions [extended-hours haemodialysis (EHD)] may improve patient survival. However, patient characteristics and treatment practices vary between the USA and Europe. We therefore investigated the effect of EHD three times weekly on survival compared with conventional haemodialysis (CHD) among European patients. Methods We included patients who were treated with haemodialysis between 2010 and 2017 from eight countries providing data to the European Renal Association–European Dialysis and Transplant Association Registry. Haemodialysis session duration and frequency were recorded once every year or at every change of haemodialysis prescription and were categorized into three groups: CHD (three times weekly, 3.5–4 h/treatment), EHD (three times weekly, ≥6 h/treatment) or other. In the primary analyses we attributed death to the treatment at the time of death and in secondary analyses to EHD if ever initiated. We compared mortality risk for EHD to CHD with causal inference from marginal structural models, using Cox proportional hazards models weighted for the inverse probability of treatment and censoring and adjusted for potential confounders. Results From a total of 142 460 patients, 1338 patients were ever treated with EHD (three times, 7.1 ± 0.8 h/week) and 89 819 patients were treated exclusively with CHD (three times, 3.9 ± 0.2 h/week). Crude mortality rates were 6.0 and 13.5/100 person-years. In the primary analyses, patients treated with EHD had an adjusted hazard ratio (HR) of 0.73 [95% confidence interval (CI) 0.62–0.85] compared with patients treated with CHD. When we attributed all deaths to EHD after initiation, the HR for EHD was comparable to the primary analyses [HR 0.80 (95% CI 0.71–0.90)]. Conclusions EHD is associated with better survival in European patients treated with haemodialysis three times weekly.