COVID-19 mortality in an area of northeast Brazil: epidemiological characteristics and prospective spatiotemporal modelling.

This study aimed to analyse the spatial-temporal distribution of COVID-19 mortality in Sergipe, Northeast, Brazil. It was an ecological study utilising spatiotemporal analysis techniques that included all deaths confirmed by COVID-19 in Sergipe, from 2 April to 14 June 2020. Mortality rates were calculated per 100 000 inhabitants and the temporal trends were analysed using a segmented log-linear model. For spatial analysis, the Kernel estimator was used and the crude mortality rates were smoothed by the empirical Bayesian method. The space-time prospective scan statistics applied the Poisson's probability distribution model. There were 391 COVID-19 registered deaths, with the majority among ⩾60 years old (62%) and males (53%). The most prevalent comorbidities were hypertension (40%), diabetes (31%) and cardiovascular disease (15%). An increasing mortality trend across the state was observed, with a higher increase in the countryside. An active spatiotemporal cluster of mortality comprising the metropolitan area and neighbouring cities was identified. The trend of COVID-19 mortality in Sergipe was increasing and the spatial distribution of deaths was heterogeneous with progression towards the countryside. Therefore, the use of spatial analysis techniques may contribute to surveillance and control of COVID-19 pandemic.

Risk clusters of COVID-19 transmission in northeastern Brazil: prospective space-time modelling.

This study aimed to analyse the trend and spatial-temporal clusters of risk of transmission of COVID-19 in northeastern Brazil. We conducted an ecological study using spatial and temporal trend analysis. All confirmed cases of COVID-19 in the Northeast region of Brazil were included, from 7 March to 22 May 2020. We used the segmented log-linear regression model to assess time trends, and the local empirical Bayesian estimator, the global and local Moran indexes for spatial analysis. The prospective space-time scan statistic was performed using the Poisson probability distribution model. There were 113 951 confirmed cases of COVID-19. The average incidence rate was 199.73 cases/100 000 inhabitants. We observed an increasing trend in the incidence rate in all states. Spatial autocorrelation was reported in metropolitan areas, and 178 municipalities were considered a priority, especially in the states of Ceará and Maranhão. We identified 11 spatiotemporal clusters of COVID-19 cases; the primary cluster included 70 municipalities from Ceará state. COVID-19 epidemic is increasing rapidly throughout the Northeast region of Brazil, with dispersion towards countryside. It was identified high risk clusters for COVID-19, especially in the coastal side.

Serum-soluble Fas and serum levels of erythropoietin in chronic kidney disease.

BACKGROUND: Soluble Fas levels (sFas) are increased in the serum of uremic patients and are associated with the presence of anemia and recombinant human EPO (rHuEPO) dosage in dialysis patients. It is possible that sFas levels are associated with an increased need for serum erythropoietin levels (Epo) in chronic kidney disease and dialysis patients in order to maintain hematocrit (Hct) levels. AIMS: To investigate the relationship between serum sFas levels, serum Epo levels and the ratio between Epo levels and Hct in uremic patients. METHODS: We studied 52 predialysis chronic kidney disease patients (CKD; 33 M, 57 +/- 12 years, hematocrit (Hct) = 37 +/- 7%), 29 peritoneal dialysis patients (PD; 12 M, 54 +/- 14 years, Hct = 36 +/- 7%), 29 hemodialysis patients (HD; 19 M, 47 +/- 14 years, Hct = 33 +/- 5%) and 29 healthy volunteers (control group 17 M, 50 +/- 16 years, Hct = 43 +/- 3%). We examined the relationship between Hct and serum levels of Epo, sFas, C-reactive protein, IL-6 and iron status. The ratio of serum Epo divided by Hct (Epo/Hct) was used as an indicator of Epo responsiveness. RESULTS: Compared to normal subjects, the CKD, PD and HD groups presented lower Hct levels and higher serum levels of sFas, Epo, Epo/Hct and IL-6. Serum levels of sFas correlated negatively with albumin (r = -0.24, p = 0.02), IL-6 (r = -0.18, p = 0.04) and Epo/Hct (r = -0.37, p < 0.001). In multivariate analysis, after adjusting for markers of iron store and inflammation, only sFas correlated with Epo/Hct. In the CKD group, there were negative correlations between serum levels of sFas and glomerular filtration rate (GFR) (r = -0.45, p < 0.001) and between Epo/Hct and GFR (r = -0.32; p = 0.02). There was a positive correlation between Epo/Hct and serum levels of sFas in the CKD group (r = 0.31, p = 0.03) and in the HD groups (r = 0.58, p = 0.001). CONCLUSION: Our findings show that serum sFas is associated with higher Epo/Hct ratio, suggesting that sFas may be a marker of Epo hyporesponsiveness in uremia. Further studies are needed to determine whether sFas is just a marker of Epo hyporesponsiveness or is also involved in its pathophysiology.

High serum levels of soluble Fas (sFas) in CKD patients: effects of renal clearance, reabsorption and synthesis.

PURPOSE: Increased serum concentrations of soluble Fas (sFas) have been reported in patients with chronic kidney disease (CKD). However, little is known about the renal clearance of sFas, whether sFas is reabsorbed in the renal tubules, or the behavior of sFas synthesis in CKD. MATERIALS AND METHODS: We studied 69 patients with CKD (60+/-15 years old, creatinine clearance 37+19 ml/min/1.73 m2) and 14 healthy subjects (61+/-17 years, creatinine clearance 79+/-24 ml/min/1.73 m2). ELISA was used to measure the levels of sFas (pg/mL) and retinol binding protein (RBP - mg/L). RT-PCR was used to quantify sFasmRNA of leukocytes. RESULTS: Serum sFas levels were significantly higher in patients with CKD (2781+/-1214 vs. 2196+/-773, p=0.02). The concentrations of sFas in 24-hour urine samples (23+/-27 vs. 40+/-17, p=0.006) and sFas Clearance (0.019+/-0.022 vs. 0.036+/-0.020, p=0.01) were significantly lower in patients with CKD. sFas clearance correlated with creatinine clearance (r=0.25, p=0.02). Urine concentrations of RBP correlated with sFas concentrations in the urine (r=0.80, p<0.001). sFasmRNA were higher in patients with CKD (3.9+/-1.8 vs. 2.5+/-0.9, p<0.001). CONCLUSIONS: In CKD patients, the decrease in renal function is followed by a decrease in sFas clearance and an increase in serum sFas. In patients with proximal tubule dysfunction (high urinary RBP concentrations), urinary sFas is also increased, suggesting that sFas is reabsorbed by the proximal tubule. It is possible that an increase in sFas synthesis also contributes to the increase of serum sFas concentrations in uremia.