population attributable fraction
Recently Published Documents


TOTAL DOCUMENTS

339
(FIVE YEARS 174)

H-INDEX

32
(FIVE YEARS 8)

2022 ◽  
pp. 174749302110706
Author(s):  
Raed A Joundi ◽  
Scott B Patten ◽  
Jeanne VA Williams ◽  
Eric E Smith

Background: The incidence of stroke in developed countries is increasing selectively in young individuals, but whether this is secondary to traditional vascular risk factors is unknown. Methods: We used the Canadian Community Health Survey from 2000 to 2016 to create a large population-representative cohort of individuals over the age of 30 and free from prior stroke. All analyses were stratified by age decile. We linked with administrative databases to determine emergency department visits or hospitalizations for acute stroke until December 2017. We calculated time trends in risk factor prevalence (hypertension, diabetes, obesity, and smoking) using meta-regression. We used Cox proportional hazard models to evaluate the association between vascular risk factors and stroke risk, adjusted for demographic, co-morbid, and social variables. We used competing risk regression to account for deaths and calculated population-attributable fractions. In a sensitivity analysis, we excluded those with prior heart disease or cancer. Results: We included 492,400 people in the analysis with 8865 stroke events over a median follow-up time of 8.3 years. Prevalence of hypertension, diabetes, and obesity increased over time while smoking decreased. Associations of diabetes, hypertension, and obesity with stroke risk were progressively stronger at younger age (adjusted hazard ratio for diabetes was 4.47, 95% confidence interval (CI) = 1.95–10.28 at age 30–39, vs 1.21, 95% CI = 0.93–1.57 at age 80+), although the obesity association was attenuated with adjustment. Smoking was associated with higher risk of stroke without a gradient across age deciles, although had the greatest population-attributable fraction at younger age. The hazard ratio for stroke with multiple concurrent risk factors was much higher at younger age (adjusted hazard ratio for 3–4 risk factors was 8.60, 95% CI = 2.97–24.9 at age 30–39 vs 1.61, 95% CI = 0.88–2.97 at age 80+) and results were consistent when accounting for the competing risk of death and excluding those with prior heart disease or cancer. Conclusions: Diabetes and hypertension were associated with progressively elevated relative risk of stroke in younger individuals and prevalence was increasing over time. The association of obesity with stroke was not significant after adjustment for other factors. Smoking had the greatest prevalence and population-attributable fraction for stroke at younger age. Our findings assist in understanding the relationship between vascular risk factors and stroke across the life span and planning public health measures to lower stroke incidence in the young.


2021 ◽  
Author(s):  
Thioub Mbaye ◽  
Maguette Mbaye ◽  
Yvan Zolo ◽  
Manal Sghiouar ◽  
Sagar Diop ◽  
...  

Introduction Pediatric aneurysms are uncommon but potentially deadly clinical conditions with varied etiology and outcomes. In low-resource countries, numerous barriers prevent the timely diagnosis and management of pediatric aneurysmal subarachnoid hemorrhage (aSAH). Thus, this study aimed to assess the mortality of pediatric aSAH stemming from limited access to pediatric neurological surgery care in Senegal. Methods Pediatric aSAH patients admitted at the authors’ institution from 2012 and 2020 were recruited. Spearman Rho’s correlation, McNemar’s test, and Wilcoxon signed-rank test were used. Odds ratios and their 95% confidence intervals were calculated, and the population attributable fraction (PAF) was used to quantify aSAH mortality attributable to lack of surgical care. Results Twenty-four pediatric patients (12 females and 12 males) aged 12.2 (95% CI=10.0-14.3) years presented with aSAH. They had 1 median aneurysm (range [1, 2]) measuring 12.6 (6.1-19.0) mm. The median WFNS grade was 3 (range [1, 4]), and the mean Fisher grade was 4 (range [1, 4]). Fifteen patients (62.5%) had surgical treatment on day 15.0 (IQR=23.0) of hospitalization. The overall mortality rate was 20.8%, and the PAF of mortality for lack of surgical treatment during hospitalization was 0.08. Conclusion Eight percent of deaths among pediatric aSAH patients who do not receive surgical treatment are attributable to lack of access to surgical treatment. Health systems strengthening policies should be implemented to address this health inequity.


2021 ◽  
Author(s):  
Anurag Bhargava ◽  
Madhavi Bhargava ◽  
Andrea Beneditti ◽  
Anura Kurpad

AbstractIntroductionThe Global TB Report 2020 estimated the population attributable fractions (PAF) for the major risk factors of TB. Undernourishment emerged as the leading risk factor accounting for 19% of the cases. The WHO however used the terms undernourishment and undernutrition interchangeably in its computation of PAF. Undernourishment is an indirect model derived estimate of decreased per capita energy availability, while undernutrition is defined by direct anthropometric measurements of nutritional status.MethodsWe re-estimated the PAF of undernutrition (instead of undernourishment) in 30 high TB burden countries, using the prevalence of undernutrition (age standardized estimate of BMI < 18.5 kg/m2 in adults for both sexes), and the relative risk (RR) of 3.2. Further, we revised PAF estimates of undernutrition with an RR of 4.49, in light of recent evidence.FindingsTwenty four percent of TB in high burden countries is attributable to undernutrition. The PAF of undernutrition was highest in Asian countries, unlike the PAF of undernourishment that was highest in Africa. The corrected estimate led up to 65% increase in number of cases attributable to undernutrition in Asian countries. More than one-third to nearly half of TB cases in India could be attributable to undernutrition.InterpretationEstimation of the PAF of TB related to undernutrition is methodologically valid and operationally relevant, rather than PAF related to undernourishment. Addressing undernutrition, the leading driver of TB in high TB burden countries (especially Asia) could enable achievement of END TB milestones of TB incidence for 2025.


F1000Research ◽  
2021 ◽  
Vol 10 ◽  
pp. 428
Author(s):  
Hugo Grisales-Romero ◽  
Juan Gabriel Piñeros-Jiménez ◽  
Emmanuel Nieto ◽  
Sandra Porras-Cataño ◽  
Nora Montealegre ◽  
...  

Background: Exposure to 2.5-micron diameter air pollutants (PM2.5) has been associated with an increased risk of illness and death worldwide; however, in Latin American health impacts assessment of this risk factor is scarce. Medellín is one of the most polluted cities in the region, with a population growth rate that is twice as high as that of other Colombian cities, which implies a growing population at risk. Methods: A descriptive study of the disease burden was carried out using the city as the unit of observation. Health events were selected based on epidemiologic evidence and the availability of the population attributable fraction associated with PM2.5. The mortality records were taken from the module of deceased of the Single Registry of Affiliates of the Health System; the morbidity records were taken from the Individual Health Services Registries. For the estimation of the burden of disease, the current Global Burden of Disease guidelines were followed. Results: Attributable disability-adjusted life years to exposure to ambient PM2.5 pollution (DALYsPM2.5) constituted 13.8% of total burden of the city. Males showed the greatest loss of DALYsPM2.5 due to acute events, while in women the greatest loss was due to chronic events. Ischemic heart disease, chronic diseases of the lower respiratory tract, and influenza and pneumonia were the events that contributed the most to DALYsPM2.5. 71.4% of the DALYsPM2.5 corresponded to mortality, mainly in the population over 65 years of age. Regarding attributable morbidity, acute events were more prevalent in both sexes, especially due to respiratory diseases Conclusion: Premature death among the elderly population has the greatest weight on burden of disease attributable to ambient PM2.5 pollution, mainly due to respiratory and cardiovascular diseases, without significant differences according to gender.


2021 ◽  
Vol 108 (Supplement_9) ◽  
Author(s):  
Anna Broadbent ◽  
Saqib Rahman ◽  
Ben Grace ◽  
Robert Walker ◽  
Fergus Noble ◽  
...  

Abstract Background Globally, oesophageal cancer incidence continues to increase. In recent years, surgical and oncological advancements have increased survival rates. Despite this, survival remains &lt;50% at five-years for patients treated with curative oesophagectomy. Previous data has suggested post-operative complications may play a role in long-term increased mortality in oesophageal cancer patients. This study aimed to examine the effect of adverse in-hospital events following oesophagectomy on the long-term prognosis for oesophageal cancer, including assessing the effect of cumulative complication burden using data from a single high-volume academic unit in the UK.  Methods Retrospective analysis of patients undergoing oesophagectomy for oesophageal adenocarcinoma or squamous cell carcinoma was performed to assess the relationship between in-hospital events and long-term survival. Analysis was limited to patients who survived to 90 days post-oesophagectomy (n = 380). Complications were graded according to the Clavien-Dindo (CD) classification and the Comprehensive Complication Index (CCI). Survival was estimated using Kaplan Meier survival curves and multivariate cox-regression, adjusting for variables known to influence survival. The absolute magnitude of effect of complications on survival was assessed using the risk-adjusted population attributable fraction (PAF), which estimates the percentage improvement in survival if specified complications were removed. Results Complications occurred in 251 patients (66.1%). ≥CD3a complications (HR1.65, 95%CI 1.15-2.38, p &lt; 0.010) and unplanned critical care admissions (HR2.24, 95%CI 1.45-3.46, p &lt; 0.001) were independently associated with worse prognosis whereas pulmonary complications and anastomotic leak were not. A CCI &gt;30 was the optimum cut-point for OS (HR1.94, 95%CI 1.36-2.78, p &lt; 0.001), and after weighting to remove confounding bias median survival was shorter with CCI&gt;30 (28vs72 months, p &lt; 0.001).  There was no difference in median survival when CCI&gt;30 occurred from major or multiple minor complications (31 vs 21 months, p = 0.096). The risk adjusted PAF for CCI&gt;30 was 8.5% (95%CI 3.6-13.1%). Conclusions Long-term survival following oesophagectomy for oesophageal cancer is significantly affected by major complications and unplanned critical care admissions. The cumulative effect of multiple post-operative minor complications is comparable to the effect of major complications on long-term survival from oesophageal cancer, and cause a substantial number of potentially preventable deaths, even in patients who survive to discharge. 


Breathe ◽  
2021 ◽  
Vol 17 (4) ◽  
pp. 210086
Author(s):  
Emilie Counil

What proportion of the risk in a given population is attributable to a risk factor? The population attributable fraction (PAF) answers this question. “Attributable to” is understood as “due to”, which makes PAFs closely related to the concept of potential impact or potential benefits of reducing the exposure. The PAF is a tool at the border between science and decision making. PAFs are estimated based on strong assumptions and the calculations are data intensive, making them vulnerable to gaps in knowledge and data. Current misconceptions include summing up PAFs to 100% or subtracting a PAF for a factor from 100% to deduce what proportion is left to be explained or prevented by other factors. This error is related to unrecognised multicausality or shared causal responsibility in disease aetiology. Attributable cases only capture cases in excess and should be regarded as a lower bound for aetiological cases, which cannot be estimated based on epidemiological data alone (exposure-induced cases). The population level might not be relevant to discuss prevention priorities based on PAFs, for instance when exposures concentrate in a subgroup of the population, as for occupational lung carcinogens and other workplace hazards. Alternative approaches have been proposed based on absolute rather than relative metrics, such as estimating potential gains in life expectancy that can be expected from a specific policy (prevention) or years of life lost due to a specific exposure that already happened (compensation).


Author(s):  
Line Holted Evensen ◽  
Carl Arne Lochen Arnesen ◽  
Frits R. Rosendaal ◽  
Maiken Elvestad Gabrielsen ◽  
Ben Michael Brumpton ◽  
...  

Background: The proportion of venous thromboembolism (VTE) events that can be attributed to established prothrombotic genotypes has been scarcely investigated in the general population. We aimed to estimate the proportion of VTEs in the population that could be attributed to established prothrombotic genotypes using a population-based case-cohort. Methods: Cases with incident VTE (n=1,493) and a randomly sampled sub-cohort (n=13,069) were derived from the Tromsø Study (1994-2012) and the Nord-Trøndelag Health (HUNT) Study (1995-2008). DNA-samples were genotyped for 17 single nucleotide polymorphism (SNPs) associated with VTE. Hazard ratios with 95% confidence intervals (CIs) were estimated in Cox regression models. Population attributable fraction (PAF) with 95% bias-corrected CIs (based on 10,000 bootstrap samples) were estimated using a cumulative model where SNPs significantly associated with VTE were added one-by-one in ranked order of the individual PAFs. Results: Six SNPs were significantly associated with VTE (rs1799963 [Prothrombin], rs2066865 [FGG], rs6025 [FV Leiden], rs2289252 [F11], rs2036914 [F11] and rs8176719 [ABO]. The cumulative PAF for the six-SNP model was 45.3% (95% CI 19.7-71.6) for total VTE and 61.7% (95% CI 19.6-89.3) for unprovoked VTE. The PAF for prothrombotic genotypes was higher for DVT (52.9%) than for PE (33.8%), and higher for those aged <70 years (66.1%) than for those aged ≥70 years (24.9%). Conclusions: Our findings suggest that 45-62% of all VTE events in the population can be attributed to known prothrombotic genotypes. The PAF of established prothrombotic genotypes was higher in DVT than in PE, and higher in the young than in the elderly.


2021 ◽  
Vol 3 ◽  
pp. 100062
Author(s):  
Ahmad Khosravi ◽  
Maryam Nazemipour ◽  
Tomohiro Shinozaki ◽  
Mohammad Ali Mansournia

2021 ◽  
Vol 6 (11) ◽  
pp. e007411
Author(s):  
Amir Kirolos ◽  
Rachel M Blacow ◽  
Arun Parajuli ◽  
Nicky J Welton ◽  
Alisha Khanna ◽  
...  

IntroductionChildhood malnutrition is widespread in low-income and middle-income countries (LMICs) and increases the frequency and severity of infections such as pneumonia. We aimed to identify studies investigating pneumonia deaths in malnourished children and estimate mortality risk by malnutrition severity.MethodsWe conducted a systematic review of MEDLINE, EMBASE and Global Health databases to identify relevant studies. We used a network meta-analysis to derive ORs of death from pneumonia for moderately and severely underweight children using low weight-for-age, the most reported measure of malnutrition. We compared meta-estimates of studies conducted before and after 2000 to assess changes in mortality risk over time. We estimated the prevalence of underweight hospitalised children from hospital-based cohort studies and calculated the population attributable fraction of in-hospital pneumonia deaths from being underweight using our results.ResultsOur network meta-analysis included 33 544 underweight children from 23 studies. The estimated OR of death from pneumonia was 2.0 (95% CI 1.6 to 2.6) and 4.6 (95% CI 3.7 to 5.9) for children moderately and severely underweight, respectively. The OR of death from pneumonia for those severely underweight was 5.3 (95% CI 3.9 to 7.4) pre-2000 and remained high post-2000 at 4.1 (95% CI 3.0 to 6.0). Prevalence of underweight children hospitalised with pneumonia varied (median 40.2%, range 19.6–66.3) but was high across many LMIC settings. We estimated a median 18.3% (range 10.8–34.6) and 40.9% (range 14.7–69.9) of in-hospital pneumonia deaths were attributable to being moderately and severely underweight, respectively.ConclusionsThe risk of death from childhood pneumonia dramatically increases with malnutrition severity. This risk has remained high in recent years with an estimated over half of in-hospital pneumonia deaths attributable to child malnutrition. Prevention and treatment of all child malnutrition must be prioritised to maintain progress on reducing pneumonia deaths.


Sign in / Sign up

Export Citation Format

Share Document