relative hazard
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2021 ◽  
pp. 115-125
Author(s):  
B.A. Revich ◽  
◽  
D.A. Shaposhnikov ◽  
S.R. Raichich ◽  
S.A. Saburova ◽  
...  

Climatic changes have already resulted and will continue to result in gradual degradation of active upper layers in permafrost due to increased average air temperature in summer. Anthrax is an example of a climate-depending bacterial infection; anthrax agent creates spores that remain viable for a long period of time they spend in cryptobiosis in permafrost. Apparent permafrost degradation is already detected in most arctic regions in Russia and it can lead to anthrax burials decay thus creating elevated risks of the infection among farm animals and people who live on these territories. Our research goal was to create specific zones in municipal districts via combining data on permafrost, number of anthrax cattle burials, ascending trends in average long-term temperatures, and population density. We developed two relative hazard coefficients for characterizing anthrax outbreaks probability for animals and local population. Basing on numeric values obtained for these two coefficients, 70 administrative districts located in 15 RF subjects in the Arctic zone were listed in a descending order as per risks of the infection occurrence. We created two score scales showing relative hazard; they indicated that the highest population risk was typical for urban districts as population density there was much high than in rural ones. Our calculations should be helpful for determining priorities when preventive activities are developed on arctic and sub-arctic territories that are endemic as per anthrax. It is also important to obtain an actual list of cattle burials and to develop spatial-time models showing anthrax outbreaks occurrence taking into account climatic warming and permafrost degradation.


2021 ◽  
pp. 115-125
Author(s):  
B.A. Revich ◽  
◽  
D.A. Shaposhnikov ◽  
S.R. Raichich ◽  
S.A. Saburova ◽  
...  

Climatic changes have already resulted and will continue to result in gradual degradation of active upper layers in permafrost due to increased average air temperature in summer. Anthrax is an example of a climate-depending bacterial infection; anthrax agent creates spores that remain viable for a long period of time they spend in cryptobiosis in permafrost. Apparent permafrost degradation is already detected in most arctic regions in Russia and it can lead to anthrax burials decay thus creating elevated risks of the infection among farm animals and people who live on these territories. Our research goal was to create specific zones in municipal districts via combining data on permafrost, number of anthrax cattle burials, ascending trends in average long-term temperatures, and population density. We developed two relative hazard coefficients for characterizing anthrax outbreaks probability for animals and local population. Basing on numeric values obtained for these two coefficients, 70 administrative districts located in 15 RF subjects in the Arctic zone were listed in a descending order as per risks of the infection occurrence. We created two score scales showing relative hazard; they indicated that the highest population risk was typical for urban districts as population density there was much high than in rural ones. Our calculations should be helpful for determining priorities when preventive activities are developed on arctic and sub-arctic territories that are endemic as per anthrax. It is also important to obtain an actual list of cattle burials and to develop spatial-time models showing anthrax outbreaks occurrence taking into account climatic warming and permafrost degradation.


2021 ◽  
Vol 8 ◽  
pp. 205435812110233
Author(s):  
David Clark ◽  
Kara Matheson ◽  
Benjamin West ◽  
Amanda Vinson ◽  
Kenneth West ◽  
...  

Background: Frailty is associated with hospitalization and mortality among dialysis patients. To now, few studies have considered the degree of frailty as a predictor of hospitalization. Objective: We evaluated whether frailty severity was associated with hospitalization after dialysis initiation. Design: Retrolective cohort study. Setting: Nova Scotia, Canada. Patients: Consecutive adult, chronic dialysis patients who initiated dialysis from January 1, 2009 to June 30, 2014, (last follow-up June, 2015). Methods: Frailty Severity, as determined by the 7-point Clinical Frailty Scale (CFS, ranging from 1 = very fit to 7 = severely frail), was measured at dialysis initiation and treated as continuous and in categories (CFS scores of 1-3, 4/5, and 6/7). Hospitalization was characterized by cumulative time admitted to hospital (proportion of days admitted/time at risk) and by the joint risk of hospitalization and death. Time at risk included time in hospital after dialysis initiation and patients were followed until transplantation or death. Results: Of 647 patients (mean age: 62 ± 15), 564 (87%) had CFS scores. The mean CFS score was 4 (“corresponding to “vulnerable”) ± 2 (“well” to “moderately frail”). In an adjusted negative binomial regression model, moderate-severely frail patients (CFS 6/7) had a >2-fold increased risk of cumulative time admitted to hospital compared to the lowest CFS category (IRR = 2.18, 95% confidence interval [CI] = 1.31-3.63). In the joint model, moderate-severely frail patients had a 61% increase in the relative hazard for hospitalization (hazard ratio [HR] = 1.61, 95% CI = 1.29-2.02) and a 93% increase in the relative hazard for death compared to the lowest CFS category (HR = 1.93, 95% CI = 1.16-3.22). Limitations: Potential unknown confounders may have affected the association between frailty severity and hospitalization given observational study design. The CFS is subjective and different clinicians may grade frailty severity differently or misclassify patients on the basis of limited availability. Conclusions: Among incident dialysis patients, a higher frailty severity as defined by the CFS is associated with both an increased risk of cumulative time admitted to hospital and joint risk of hospitalization and death.


Author(s):  
Boyi Abubakar Dalatu ◽  
Shehu Ladan ◽  
Nwoji O. Jude ◽  
Shamsuddeen A. Sabo

A problem in population-based cancer survival analysis is the estimation of relative hazard between patients with different characteristics handled in the same registry center. In this work, we use the Cox proportional hazard model to find an estimated hazard ratio between two patients having different characteristics. The procedure was then fitted has been applied on the data collected from Ahmadu Bello University Teaching Hospital (ABUTH) Zaria Cancer Registry Center. The result indicated that female and frail patients are more prone to failure than male and non frail patients respectively.


2020 ◽  
Author(s):  
Roshan Karunamuni ◽  
Minh-Phuong Huynh-Le ◽  
Chun Fan ◽  
Wesley Thompson ◽  
Rosalind Eeles ◽  
...  

AbstractIntroductionPolygenic hazard score (PHS) models are associated with age at diagnosis of prostate cancer. Our model developed in Europeans (PHS46), showed reduced performance in men with African genetic ancestry. We used a cross-validated search to identify SNPs that might improve performance in this population.Material and MethodsAnonymized genotypic data were obtained from the PRACTICAL consortium for 6,253 men with African genetic ancestry. Ten iterations of a ten-fold cross-validation search were conducted, to select SNPs that would be included in the final PHS46+African model. The coefficients of PHS46+African were estimated in a Cox proportional hazards framework using age at diagnosis as the dependent variable and PHS46, and selected SNPs as predictors. The performance of PHS46 and PHS46+African were compared using the same cross-validated approach.ResultsThree SNPs (rs76229939, rs74421890, and rs5013678) were selected for inclusion in PHS46+African. All three SNPs are located on chromosome 8q24. PHS46+African showed substantial improvements in all performance metrics measured, including a 75% increase in the relative hazard of those in the upper 20% compared to the bottom 20% (2.47 to 4.34) and a 20% reduction in the relative hazard of those in the bottom 20% compared to the middle 40% (0.65 to 0.53).ConclusionsWe identified three SNPs that substantially improved the association of PHS46 with age at diagnosis of prostate cancer in men with African genetic ancestry to levels comparable to Europeans and Asians. A strategy of building on established statistical models might benefit ancestral groups generally under-represented in genome-wide association studies.


2020 ◽  
Vol 7 ◽  
pp. 205435812095743
Author(s):  
Karthik K. Tennankore ◽  
Lakshman Gunaratnam ◽  
Rita S. Suri ◽  
Seychelle Yohanna ◽  
Michael Walsh ◽  
...  

Background: Understanding how frailty affects patients listed for transplantation has been identified as a priority research need. Frailty may be associated with a high risk of death or wait-list withdrawal, but this has not been evaluated in a large multicenter cohort of Canadian wait-listed patients. Objective: The primary objective is to evaluate whether frailty is associated with death or permanent withdrawal from the transplant wait list. Secondary objectives include assessing whether frailty is associated with hospitalization, quality of life, and the probability of being accepted to the wait list. Design: Prospective cohort study. Setting: Seven sites with established renal transplant programs that evaluate patients for the kidney transplant wait list. Patients: Individuals who are being considered for the kidney transplant wait list. Measurements: We will assess frailty using the Fried Phenotype, a frailty index, the Short Physical Performance Battery, and the Clinical Frailty Scale at the time of listing for transplantation. We will also assess frailty at the time of referral to the wait list and annually after listing in a subgroup of patients. Methods: The primary outcome of the composite of time to death or permanent wait-list withdrawal will be compared between patients who are frail and those who are not frail and will account for the competing risks of deceased and live donor transplantation. Secondary outcomes will include number of hospitalizations and length of stay, and in a subset, changes in frailty severity over time, change in quality of life, and the probability of being listed. Recruitment of 1165 patients will provide >80% power to identify a relative hazard of ≥1.7 comparing patients who are frail to those who are not frail for the primary outcome (2-sided α = .05), whereas a more conservative recruitment target of 624 patients will provide >80% power to identify a relative hazard of ≥2.0. Results: Through December 2019, 665 assessments of frailty (inclusive of those for the primary outcome and all secondary outcomes including repeated measures) have been completed. Limitations: There may be variation across sites in the processes of referral and listing for transplantation that will require consideration in the analysis and results. Conclusions: This study will provide a detailed understanding of the association between frailty and outcomes for wait-listed patients. Understanding this association is necessary before routinely measuring frailty as part of the wait-list eligibility assessment and prior to ascertaining the need for interventions that may modify frailty. Trial Registration: Not applicable as this is a protocol for a prospective observational study.


2019 ◽  
Vol 156 (6) ◽  
pp. S-858
Author(s):  
Ravy K. Vajravelu ◽  
Lawrence Copelovitch ◽  
Mark T. Osterman ◽  
Frank I. Scott ◽  
Ronac Mamtani ◽  
...  

2019 ◽  
Vol 98 (1) ◽  
pp. 87-89
Author(s):  
V. A. Kislitsyn ◽  
Tatyana A. Shashina ◽  
N. S. Dodina

Risk assessment of acute inhalation effects on the population has methodological features at all stages of the research. When choosing priority substances, a modification of the method for calculating the relative hazard index by the emission value (in g/sec) is proposed. To assess acute risk, 1-hour averaging of concentrations coinciding in duration with reference levels of acute inhalation effects (ARfC) is used. The use in modeling program of a maximum hourly emission value for each source results in an unreasonable overestimation of the values of 1-hour concentrations. The standard parameters of the emission sources from the report on permissible emissions ( PDV) do not provide the data for the mode of sources (on/off), the actual emission rates (g/sec) for each hour, and other parameters that specify the sources operation. Recommendations were developed for calculation of 1-hour concentrations close to real, in assessing the exposure, structure, and format of the additional data and a computer package for the data connection to AERMOD and ISCST3 models, as well as for the truncation of the time series of calculated 1-hour concentrations at 95-98th percentile. Features of the acute risk indices calculation - coefficients (AHQ) and indices (AHI) are described. Using the hourly values of the time series of concentrations the highest AHQ value is determined at each exposure point, which is used to estimate the level of acute risk from a substance. To calculate the hazard index (AHI) of the substances affecting the same critical organs/systems, the AHQ hourly values of individual substances are summarized at each exposure point, the highest AHI value is determined, which is used to assess the level of acute risk from exposure to substances with unidirectional action. The approbation of the described methodical approaches has shown their effectiveness in determining the values of exposures and risks close to real values. Their use has reduced the values of AHQ and AHI acute risk indices to "plausible" values by 2 and 3.7 times, respectively.


2018 ◽  
Vol 36 (18_suppl) ◽  
pp. LBA6002-LBA6002 ◽  
Author(s):  
Annie Park ◽  
Amy Albaster ◽  
Hanjie Shen ◽  
Loren K. Mell ◽  
Jed Abraham Katzel

LBA6002 Background: Generalized competing event (GCE) models have been used to stratify patients with cancer according to their relative hazard for cancer death versus death from other causes. We evaluated outcomes for head and neck cancer (HNC) patients treated at Kaiser Permanente Northern California (KPNC) based on demographic data and comorbidities using a GCE model. Methods: We identified 884 HNC patients diagnosed 2000-2015 from the KPNC cancer registry, age 18-85 and stage II-IVB by AJCC 7th edition. Using the GCE proportional relative hazards model, controlling for age, sex, tumor site, and Charlson comorbidity index (CCI), we identified associations between these factors and the relative hazard for HNC-specific mortality (ω+ ratio, ‘gcerisk’ package in R). Death, disenrollment, and end of study (12/31/2016) were used as censoring events. Logistic regression models estimated the odds of receiving intensive treatment (platinum based regimen), adjusting for the same covariates plus stage, smoking, and alcohol abuse history. Results: With a median follow-up of 2.9 years, 271 patients died of cancer, and 93 of non-cancer causes. Compared to male, females were less likely to receive intensive chemotherapy (35% vs. 46%, p = 0.006) and radiation (60% vs. 70%, p = 0.008). On GCE analysis, female patients had an increased relative hazard ratio (RHR) for death from HNC vs. other causes (adjusted RHR 1.92; 95% CI 1.07-3.43), indicating they may be relatively undertreated. Conclusions: Female patients in our cohort may be undertreated in clinical practice, potentially missing the opportunity to aggressively treat their HNC. This study supports the use of a GCE methodology to objectively identify patients more likely to benefit from treatment intensification. These findings may help guide future research in health disparities.[Table: see text]


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