scholarly journals Discrepancies between observed data and predictions from mathematical modelling of the impact of screening interventions onChlamydia trachomatisprevalence

2018 ◽  
Author(s):  
Joost Smid ◽  
Christian L. Althaus ◽  
Nicola Low
Keyword(s):  
Mathematical Modelling ◽  
Natural Infection ◽  
Credible Interval ◽  
Population Based ◽  
Chlamydia Infection ◽  
Infected People ◽  
Modelling Studies ◽  
The Impact ◽  
Over Time ◽  
Partial Immunity

Mathematical modelling studies ofC. trachomatistransmission predict that interventions to screen and treat chlamydia infection will reduce prevalence to a greater degree than that observed in empirical population-based studies. We investigated two factors that might explain this discrepancy: partial immunity after natural infection clearance and differential screening coverage according to infection risk. We used four variants of a compartmental model for heterosexualC. trachomatistransmission, parameterized using data from England about sexual behaviour andC. trachomatistesting, diagnosis and prevalence, and Markov Chain Monte Carlo methods for statistical inference. A model in which partial immunity follows natural infection clearance and the proportion of tests done in chlamydia-infected people decreases over time fitted the data best. The model predicts that partial immunity reduced susceptibility to reinfection by 72% (95% Bayesian credible interval 57-86%). The estimated screening rate was 4.6 (2.6-6.5) times higher for infected than for uninfected women in 2000; this decreased to 2.1 (1.4-2.9) in 2011. Other factors not included in the model could have further reduced the expected impact of screening. Future mathematical modelling studies investigating the effects of screening interventions onC. trachomatistransmission should incorporate host immunity and changes over time in the targeting of screening.

scholarly journals The Impact of COPD in Trends of Urinary Tract Infection Hospitalizations in Spain, 2001–2018: A Population-Based Study Using Administrative Data

2020 ◽  
Vol 9 (12) ◽  
pp. 3979
Author(s):  
Javier de Miguel-Diez ◽  
Romana Albaladejo-Vicente ◽  
Domingo Palacios-Ceña ◽  
David Carabantes-Alarcon ◽  
José Javier Zamorano-Leon ◽  
...  
Keyword(s):  
Urinary Tract ◽  
Protective Factor ◽  
Multivariable Analysis ◽  
Population Based ◽  
Chronic Obstructive ◽  
Obstructive Pulmonary Disease ◽  
Men And Women ◽  
Tract Infections ◽  
The Impact ◽  
Over Time

(1) Background: To examine trends in incidence and outcomes of urinary tract infections (UTIs) among men and women with or without chronic obstructive pulmonary disease (COPD), and to identify the predictors for in-hospital mortality (IHM). (2) Methods: We included patients (aged ≥40 years) who were hospitalized with UTIs between 2001 and 2018. Data were collected from the Spanish National Hospital Discharge Database. (3) Results: We identified 748,458 UTI hospitalizations, 6.53% with COPD. The UTIs incidence increased over time. It was 1.55 times higher among men COPD patients than among non-COPD men (incidence rate ratio (IRR) 1.55; 95% CI 1.53–1.56). The opposite happened in women with COPD compared to non-COPD women (IRR 0.30; 95% CI 0.28–0.32). IHM was higher in men with COPD than non-COPD men (5.58% vs. 4.47%; p < 0.001) and the same happened in women (5.62% vs. 4.92%; p < 0.001). The risk of dying increased with age and comorbidity, but the urinary catheter was a protective factor among men (OR 0.75; 95% CI 0.64–0.89). Multivariable analysis showed a significant reduction in the IHM over time for men and women with COPD. Suffering from COPD only increased the risk of IHM among men (OR 1.07; 95% CI 1.01–1.13). (4) Conclusions: The incidence of UTIs increased over time. Suffering COPD increased the risk of IHM among men, but not among women.

scholarly journals Changes in health and functioning of care home residents over two decades: what can we learn from population based studies?

2020 ◽  
Author(s):  
Robert O Barker ◽  
Barbara Hanratty ◽  
Andrew Kingston ◽  
Sheena Ramsay ◽  
Fiona E Matthews
Keyword(s):  
Care Home ◽  
Population Based ◽  
Severe Disability ◽  
Support Needs ◽  
Cross Sectional ◽  
England And Wales ◽  
Care Home Staff ◽  
Using Data ◽  
The Impact ◽  
Over Time

Background Care home residents have complex care and support needs, as demonstrated by their vulnerability during the COVID-19 pandemic. There is a perception that the needs of residents have increased, but evidence is limited. We investigated changes in health and functioning of care home residents over two decades in England and Wales. Methods We conducted a repeated cross-sectional analysis over a 24-year period (1992-2016), using data from three longitudinal studies, the Cognitive Function and Ageing Studies (CFAS) I and II and English Longitudinal Study of Ageing (ELSA). To adjust for ageing of respondents over time results are presented for the 75-84 age group. Results Analysis of 2,280 observations from 1,745 care home residents demonstrated increases in severe disability (difficulty in at least two from washing, dressing and toileting). The prevalence of severe disability increased from 63% in 1992 to 87% in 2014 (subsequent fall in 2016 although wide confidence intervals). The prevalence of complex multimorbidity (problems in at least three out of six body systems) increased within studies over time, from 33% to 54% in CFAS I/II between 1992 and 2012, and 26% to 54% in ELSA between 2006 and 2016. Conclusion Over two decades, there has been an increase in disability and the complexity of health problems amongst care home residents in England and Wales. A rise in support needs for residents places increasing demands on care home staff and health professionals. This is an important concern for policymakers when considering the impact of COVID-19 infection in care homes.

scholarly journals Heart Failure After Myocardial Infarction - A Population-Based Study

Circulation ◽  
2001 ◽  
Vol 103 (suppl_1) ◽  
pp. 1359-1359
Author(s):  
Jens P Hellermann ◽  
Steven J Jacobsen ◽  
Barbara P Yawn ◽  
Susan Weston ◽  
Margaret M Redfield ◽  
...  
Keyword(s):  
Myocardial Infarction ◽  
Heart Failure ◽  
Clinical Characteristics ◽  
Reperfusion Therapy ◽  
Population Based ◽  
Proportional Hazard ◽  
Population Based Study ◽  
History Of ◽  
The Impact ◽  
Over Time

P46 While heart failure (HF), an emerging epidemic, complicates myocardial infarction (MI), little is known on the predictors of HF post-MI, in particular the impact of reperfusion therapy. This population-based study was undertaken to examine the association between clinical characteristics and post-MI HF between 1979 and 1994. Hospitalized incident MIs were validated using enzymes, chest pain, and Minnesota coding of the ECG. Framingham criteria were used to ascertain both in- and outpatient HF. Proportional hazard regression was used to identify predictors of CHF. In the study period, 1657 patients (pts.) (mean age 67.2 ± 13.9 years, 43% women) had an incident MI. History of diabetes, hypertension and prior HF was found in 19%, 54% and 11% of pts respectively. After 5 years, 43% of pts had experienced HF. Factors independently associated with HF were (see table). There was a 2% decline per year in occurrence of HF. Adding reperfusion therapy in the model attenuated the association between year and HF (adjusted RR for reperfusion 0.67, 95% CI 0.53, 0.84, p=0.006; adjusted for year 0.99; 95% CI 0.97, 1.01, p=0.37). Thus, while remaining frequent post-MI CHF has declined over time. Reperfusion therapy accounted for most of the effect of year. Table 1.

Cancer Complications At the Time of Multiple Myeloma Diagnosis and the Impact of Monoclonal Gammopathy of Undetermined Significance (MGUS) Follow-up: A Population-Based Study

Blood ◽  
2012 ◽  
Vol 120 (21) ◽  
pp. 3996-3996
Author(s):  
Jacob D Gundrum ◽  
Joan M Neuner ◽  
Ronald S. Go
Keyword(s):  
Multiple Myeloma ◽  
Kidney Injury ◽  
Cord Compression ◽  
Population Based ◽  
Complication Rates ◽  
Population Based Study ◽  
Major Complications ◽  
The Impact ◽  
Over Time

Abstract Abstract 3996 Background: We performed a population-based study to determine the rates of major complications related to multiple myeloma, lymphoplasmacytic lymphoma, and Waldenstrom's macroglobulinemia (hence abbreviated as MM) at the time of cancer diagnosis in the US, their trends over time, disparities among demographic subsets, and the impact of preceding follow-up for MGUS. Methods: Data were obtained from the Surveillance Epidemiology and End Results (SEER) database linked to Medicare claims. We considered patients age >/= 67 years with MM diagnosed from 1994–2007 (N = 28,879). We excluded those who were diagnosed by autopsy or death certificate only, had invasive cancers within 5 years prior to MM diagnosis, lacked date of either diagnosis or death, lacked complete Medicare parts A/B coverage 15 months prior to or 3 months after MM diagnosis date (or to date of death, if death was within 3 months), and receiving dialysis for other conditions (n = 11,450). Major complications including acute kidney injury (AKI), dialysis requirement, cord compression, fracture, and hypercalcemia presenting within 3 months before or after MM diagnosis were obtained from diagnosis and procedure claims. MGUS follow-up was defined as having a diagnosis claim 3–15 months prior to MM diagnosis. Results: Of the 17,429 MM patients included in our study, 50.6% were males and the median age was 77 years. Major complications were present at diagnosis in 31.9% of the patients in the following order of frequency: fracture (16.6%), acute kidney injury (13.5%), hypercalcemia (5.5%), dialysis (5.3%), and cord compression (2.4%). There was a significant increase in most complication rates (unadjusted) over time (P < .001) except for hypercalcemia and cord compression. Females were more likely to have hypercalcemia (6.0% vs 5.1%; P = .005) or fracture (19.4% vs 13.9%; P < .001), but men were more likely to have AKI (14.6% vs 12.3%; P < .001) and to require dialysis (5.8% vs 4.8%; P = .002). Blacks were more likely to have hypercalcemia (7.1%; P < .001), AKI (18.3%; P < .001), cord compression (3.1%; P = .009), or require dialysis (7.8%; P < .001), but were less likely to have fracture (14.6%; P < .001) compared to whites (5.4%, 12.9%, 2.3%, 5.0%, and 17.1%, respectively) or other races (4.6%, 12.5%, 1.0 %, 4.8%, and 16.0%, respectively). Overall, 6% of the patients had MGUS follow-up (n = 1,037) preceding MM diagnosis with an increasing trend from 2.6% in 1994 to 6.9% in 2007 (P < .001). Complication rates were lower in the group with MGUS follow-up compared to those without follow-up: any complication (20.8% vs 32.6%; P < .001), AKI (10.1% vs 13.7%; P < .001), cord compression (1.4% vs 2.4%; P < .001), dialysis (3.4% vs 5.4%; P = .004), fracture (11.0% vs 17.0%; P < .001), and hypercalcemia (2.4% vs 5.7%; P < .001). Conclusions: At the time of MM diagnosis, major cancer-related complications were present in a third of patients with increasing trends from 1994–2007 for fracture, AKI, and requirement for dialysis. Complication rates varied among gender and race. Patients being followed for MGUS had significantly lower complications rates compared to those who were not. Disclosures: No relevant conflicts of interest to declare.

Improved Survival for Patients with CLL in the Era of Combination Chemoimmunotherapy - a Danish Population Based Study

Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 1740-1740 ◽  
Author(s):  
Caspar da Cunha-Bang ◽  
Jacob Simonsen ◽  
Klaus Rostgaard ◽  
Christian H Geisler ◽  
Henrik Hjalgrim ◽  
...  
Keyword(s):  
Overall Survival ◽  
Survival Probability ◽  
Population Based ◽  
Danish Population ◽  
Younger Patients ◽  
Risk Of Death ◽  
Improvement In Survival ◽  
The Impact ◽  
First Time ◽  
Over Time

Abstract Background The treatment of chronic lymphocytic leukemia (CLL) is in rapid transition. As single agents, Fludarabine (F) was shown to be superior to chlorambucil (Rai, NEJM, 2000). Soon after F with Cyclophosphamide (C), showed superiority to F alone (Eichhorst, Blood, 2006; Flinn, JCO, 2007, Catovsky, Lancet, 2007). Subsequently, the addition of CD20 antibody rituximab (R) to FC for the first time showed a survival benefit for fit patients in a clinical trial (Hallek, Lancet, 2010). Likewise, in unfit patients the addition of CD20 antibodies to chlorambucil led to increased overall survival (Goede, NEJM, 2014). Eventually, BCR-targeted treatment for patients harboring TP53 aberrations demonstrated promising results (Farooqui, Lancet Onc, 2015). Here we assess the impact of these successive changes of therapy on the survival of patients with CLL in a Danish population-based cohort. Methods We studied the survival of a population-based cohort of CLL patients reported to the Danish Cancer Registry 1978-2013. Patients were categorized according to year of diagnosis from 1978-1994, 1995-2000, 2001-2005 and 2006-2013. For each CLL patient, we randomly selected 50 controls from the general population matched on age, gender and municipality. Kaplan MeierÕs survival curves and Hazard ratios (HR) and 95% confidence interval (95%CI) for death since time of diagnosis /matching date for controls were calculated. Change in survival probability relative to the controls with stratification on gender, age and calendar period of diagnosis was assessed. Results In total, 10500 patients were diagnosed with CLL in Denmark from 1978 to 2013 as follows: 1978-1994: 4651, 1995-2000: 1622, 2001-2005: 1664 and 2006-2013: 2563. Thus, the reported incidence of CLL increased slightly after year 2000. Overall, we observed a continuously decreasing risk of death for patients with CLL compared to matched controls, with HRs from 3.47 (3.37 - 3.58) to 2.09 (1.96 - 2.24) for patients diagnosed 1978-1994 and 2005-2013, respectively. In inter group analyses, a significant stepwise reduction in risk of death was observed for each period (Figure 1). In all age groups and calendar periods, male patients had an inferior survival compared to female patients and younger patients survived longer than older patients (p<0.0001). Discussion A significant improvement in survival probability for patients with CLL over time was found. This coincides with the introduction of FCR as standard therapy for younger patients with CLL (approval by EMA in 2009, affecting the cohort diagnosed 2006-2013). Significant survival improvement was also observed in the 2001-2005 cohort, possibly due to a shift to combination chemotherapy. Also for elderly patients, otherwise expected to get less intensive treatment in part due to co-morbidities, the survival improved over time. This may be accounted for by the introduction of semi-intensive chemotherapy like bendamustine, reduced intensity FC(R) and more recently chlorambucil combined with CD20-targeting antibodies. For the first time, we here present population-based data showing significant improvement in survival for patients with CLL in parallel with the introduction of new chemo-immunotherapeutic regimens into clinical practice. These data substantiate the reported increased survival for patients treated with chemo-immunotherapy in clinical studies. Further investigation and cross-reference with treatment databases are warranted in order to assess the impact of new targeted treatment options for CLL. Figure 1. Overall survival for patients (70-79 and 50-59 years), lower four curves; upper four curves represent matched controls. Figure 1. Overall survival for patients (70-79 and 50-59 years), lower four curves; upper four curves represent matched controls. Disclosures Geisler: GlaxoSmithKline: Consultancy; Novartis: Consultancy; Janssen: Consultancy; Celgene: Consultancy; Gilead: Consultancy; Roche: Consultancy. Niemann:Novartis: Other: Travel grant; Janssen: Consultancy; Roche: Consultancy; Gilead: Consultancy.

Incidence of diabetes mellitus in a population-based cohort of HIV-infected and non-HIV-infected persons: the impact of clinical and therapeutic factors over time

2014 ◽  
Vol 31 (10) ◽  
pp. 1185-1193 ◽  
Author(s):  
A. Tripathi ◽  
A. D. Liese ◽  
J. M. Jerrell ◽  
J. Zhang ◽  
A. A. Rizvi ◽  
...  
Keyword(s):  
Diabetes Mellitus ◽  
Population Based ◽  
Therapeutic Factors ◽  
The Impact ◽  
Over Time

scholarly journals OP02 Impact of therapeutic strategies on intestinal resection rate in paediatric inflammatory bowel diseases: A population-based cohort study over a 24-year period (1988–2011)

2020 ◽  
Vol 14 (Supplement_1) ◽  
pp. S001-S003
Author(s):  
D Ley ◽  
A Leroyer ◽  
C Dupont ◽  
H Sarter ◽  
V Bertrand ◽  
...  
Keyword(s):  
Inflammatory Bowel Diseases ◽  
Intestinal Resection ◽  
Population Based ◽  
Therapeutic Strategies ◽  
Resection Rate ◽  
Related Hospitalisation ◽  
Bowel Diseases ◽  
Inflammatory Bowel ◽  
The Impact ◽  
Over Time

Abstract Background Few data are available at the population level on the impact of the changes in therapeutic strategies over the last decades on inflammatory bowel diseases (IBD) long-term outcomes. We have evaluated the impact of immunosuppressants (IS) and anti-TNF introduction on intestinal resection rate, hospitalisation, and Crohn’s disease (CD) behaviour progression in a large population-based paediatric-onset IBD cohort. Methods Paediatric-onset IBD (&lt;17 years) were issued from a prospective population-based study in France between 1988 and 2011 and were retrospectively followed until 2013. Risks for intestinal resection, hospitalisation and complicated CD behaviour (stricturing or penetrating) were compared between three diagnostic periods: 1988–1993 (P1), 1994–2000 (P2) and 2001–2011 (P3) using Kaplan–Meier survival analyses. Results One thousand and sixty-one patients diagnosed with CD (n = 800) or ulcerative colitis (UC, n = 261) were followed up during a median of 8.9 years (IQR: 5.0–14.7). Median age at diagnosis was 14.3 years (IQR: 11.8–16.0) and half of patients were female (n = 530, 50%). Over time, in CD, the IS and anti-TNF exposure rate increased from, respectively, 32% (P1) to 75% (P3) and from 0% (P1) to 51% (P3) at 5 years. In UC, IS and anti-TNF exposure increased from, respectively, 9% (P1) to 65% (P3) and from 0% (P1) to 40% (P3) at 5 years. In parallel, risk for intestinal resection at 5 years significantly declined in CD (P1: 35%, P2: 30%, P3: 20%, p &lt; 0.05). No significant change in 5-year colectomy risk in UC was observed (P1: 14%, P2: 19%, P3: 9%, p = 0.08). Exposure to corticosteroid at 5 years of diagnosis did not change over time (P1: 10%, P2: 10%, P3: 8%, p = 0.54). Risk for IBD-flare-related hospitalisation at 5 years was similar over time in CD (P1: 43%, P2: 45%, P3: 43%, p = 0.60) and UC (P1: 31%, P2: 46%, P3: 52%, p = 0.10). Progression to a complicated behaviour in CD at 5 years did not change over time (P1: 31%, P2: 33%, P3: 25%, p = 0.20). Conclusion In parallel with the increased use of IS and anti-TNF agents, risk for intestinal resection within 5 years after diagnosis decreased in paediatric CD, whereas risks for flare-related hospitalisation and behaviour progression remained unchanged over a 24-year period.

scholarly journals The Impact of Rubella Vaccine Introduction on Rubella Infection and Congenital Rubella Syndrome: A Systematic Review of Mathematical Modelling Studies

Vaccines ◽  
2021 ◽  
Vol 9 (2) ◽  
pp. 84
Author(s):  
Nkengafac Villyen Motaze ◽  
Zinhle E. Mthombothi ◽  
Olatunji Adetokunboh ◽  
C. Marijn Hazelbag ◽  
Enrique M. Saldarriaga ◽  
...  
Keyword(s):  
Systematic Review ◽  
Mathematical Modelling ◽  
Systematic Reviews ◽  
Methodological Quality ◽  
Older Children ◽  
Data Synthesis ◽  
Vaccine Introduction ◽  
Congenital Rubella ◽  
Modelling Studies ◽  
The Impact

Introduction: Rubella vaccines have been used to prevent rubella and congenital rubella syndrome (CRS) in several World Health Organization (WHO) regions. Mathematical modelling studies have simulated introduction of rubella-containing vaccines (RCVs), and their results have been used to inform rubella introduction strategies in several countries. This systematic review aimed to synthesize the evidence from mathematical models regarding the impact of introducing RCVs. Methods: We registered the review in the international prospective register of systematic reviews (PROSPERO) with registration number CRD42020192638. Systematic review methods for classical epidemiological studies and reporting guidelines were followed as far as possible. A comprehensive search strategy was used to identify published and unpublished studies with no language restrictions. We included deterministic and stochastic models that simulated RCV introduction into the public sector vaccination schedule, with a time horizon of at least five years. Models focused only on estimating epidemiological parameters were excluded. Outcomes of interest were time to rubella and CRS elimination, trends in incidence of rubella and CRS, number of vaccinated individuals per CRS case averted, and cost-effectiveness of vaccine introduction strategies. The methodological quality of included studies was assessed using a modified risk of bias tool, and a qualitative narrative was provided, given that data synthesis was not feasible. Results: Seven studies were included from a total of 1393 records retrieved. The methodological quality was scored high for six studies and very high for one study. Quantitative data synthesis was not possible, because only one study reported point estimates and uncertainty intervals for the outcomes. All seven included studies presented trends in rubella incidence, six studies reported trends in CRS incidence, two studies reported the number vaccinated individuals per CRS case averted, and two studies reported an economic evaluation measure. Time to CRS elimination and time to rubella elimination were not reported by any of the included studies. Reported trends in CRS incidence showed elimination within five years of RCV introduction with scenarios involving mass vaccination of older children in addition to routine infant vaccination. CRS incidence was higher with RCV introduction than without RCV when public vaccine coverage was lower than 50% or only private sector vaccination was implemented. Although vaccination of children at a given age achieved slower declines in CRS incidence compared to mass campaigns targeting a wide age range, this approach resulted in the lowest number of vaccinated individuals per CRS case averted. Conclusion and recommendations: We were unable to conduct data synthesis of included studies due to discrepancies in outcome reporting. However, qualitative assessment of results of individual studies suggests that vaccination of infants should be combined with vaccination of older children to achieve rapid elimination of CRS. Better outcomes are obtained when rubella vaccination is introduced into public vaccination schedules at coverage figures of 80%, as recommended by WHO, or higher. Guidelines for reporting of outcomes in mathematical modelling studies and the conduct of systematic reviews of mathematical modelling studies are required.

scholarly journals Per-partnership transmission probabilities for Chlamydia trachomatis infection: evidence synthesis of population-based survey data

2020 ◽  
Author(s):  
Joanna Lewis ◽  
Peter J White ◽  
Malcolm J Price
Keyword(s):  
Evidence Synthesis ◽  
Credible Interval ◽  
Transmission Probability ◽  
Monte Carlo Sampling ◽  
Population Based ◽  
Control Measures ◽  
Chlamydia Infection ◽  
National Study ◽  
Transmitted Infection ◽  
Chlamydia Trachomatis Infection

Abstract Background Chlamydia is the most commonly diagnosed sexually transmitted infection worldwide. Mathematical models used to plan and assess control measures rely on accurate estimates of chlamydia’s natural history, including the probability of transmission within a partnership. Several methods for estimating transmission probability have been proposed, but all have limitations. Methods We have developed a new model for estimating per-partnership chlamydia transmission probabilities from infected to uninfected individuals, using data from population-based surveys. We used data on sexual behaviour and prevalent chlamydia infection from the second UK National Study of Sexual Attitudes and Lifestyles (Natsal-2) and the US National Health and Nutrition Examination Surveys 2009–2014 (NHANES) for Bayesian inference of average transmission probabilities, across all new heterosexual partnerships reported. Posterior distributions were estimated by Markov chain Monte Carlo sampling using the Stan software. Results Posterior median male-to-female transmission probabilities per partnership were 32.1% [95% credible interval (CrI) 18.4–55.9%] (Natsal-2) and 34.9% (95%CrI 22.6–54.9%) (NHANES). Female-to-male transmission probabilities were 21.4% (95%CrI 5.1–67.0%) (Natsal-2) and 4.6% (95%CrI 1.0–13.1%) (NHANES). Posterior predictive checks indicated a well-specified model, although there was some discrepancy between reported and predicted numbers of partners, especially in women. Conclusions The model provides statistically rigorous estimates of per-partnership transmission probability, with associated uncertainty, which is crucial for modelling and understanding chlamydia epidemiology and control. Our estimates incorporate data from several sources, including population-based surveys, and use information contained in the correlation between number of partners and the probability of chlamydia infection. The evidence synthesis approach means that it is easy to include further data as it becomes available.

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