Estimation of mortality rate ratios for chronic conditions with misclassification of disease status at death.

Estimation of mortality rates and mortality rate ratios (MRR) of diseased and non-diseased individuals is a core metric of disease impact used in chronic disease epidemiology. Estimation of mortality rates is often conducted through retrospective linkage of information from nationwide surveys such as the National Health Interview Survey (NHIS) and death registries. These surveys usually collect information on disease status during only one study visit.

Five-year outcome in 18 010 patients from the German Aortic Valve Registry.

Objectives: To determine the 5-year outcome in patients treated by isolated transcatheter aortic valve implantation (TAVI) or surgical aortic valve replacement (sAVR)-a prospective observational cohort study.

Methods: A total of 18 010 patients were included (n = 8942 TAVI and n = 9068 sAVR) in the German Aortic Valve Registry (GARY) who were treated in 2011 and 2012 at 92 sites in central Germany. Eligible patients with TAVI and sAVR were matched using propensity scores in a nearest-neighbour approach.

Impact of new pacemaker implantation following surgical and transcatheter aortic valve replacement on 1-year outcome.

Objectives: The purpose of this study was to evaluate the incidence of new pacemaker implantation (NPMI) after surgical aortic valve replacement (SAVR) and transcatheter aortic valve replacement (TAVR), and investigate its influence on 1-year mortality.

Methods: Patients who were enrolled in 'The German Aortic Valve Registry' undergoing isolated TAVR or SAVR between 2011 and 2015 were analysed. The rate of NPMI was analysed for both groups and multivariable Cox regression analysis was performed to investigate the possible independent association between NPMI and 1-year mortality.

Patients at Intermediate Surgical Risk Undergoing Isolated Interventional or Surgical Aortic Valve Implantation for Severe Symptomatic Aortic Valve Stenosis.

Background: Transcatheter aortic valve replacement (TAVR) is increasingly being used for treatment of severe aortic valve stenosis in patients at intermediate risk for surgical aortic valve replacement (SAVR). Currently, real-world data comparing indications and clinical outcomes of patients at intermediate surgical risk undergoing isolated TAVR with those undergoing SAVR are scarce.

Methods: We compared clinical characteristics and outcomes of patients with intermediate surgical risk (Society of Thoracic Surgeons score 4%-8%) who underwent isolated TAVR or conventional SAVR within the prospective, all-comers German Aortic Valve Registry.

Rapid Deployment Versus Conventional Bioprosthetic Valve Replacement for Aortic Stenosis.

Background: Surgical aortic valve replacement using conventional biological valves (CBVs) is the standard of care for treatment of old patients with aortic valve disease. Recently, rapid deployment valves (RDVs) have been introduced.

Objectives: The purpose of this study was to report the nationwide German experience concerning RDVs for treatment of aortic valve stenosis and provide a head-to-head comparison with CBVs.

Impact of quality of life (QoL) on glycemic control (HbA1c) among adolescents and emerging adults with long-duration type 1 diabetes: A prospective cohort-study.

Objective: To evaluate the impact of self-reported chronic-generic and condition-specific quality of life (QoL) on glycemic control among adolescents and emerging adults with long-duration type 1 diabetes (T1D) in a longitudinal design.

Methods: The database used was a nationwide cohort study of patients with ≥10 years T1D duration at baseline in Germany. The baseline questionnaire survey was conducted in 2009-2010, the follow-up survey in 2012-2013; additional clinical data of routine care procedures were linked.

Quality of Life After Transcatheter Aortic Valve Replacement: Prospective Data From GARY (German Aortic Valve Registry).

Objectives: This study sought to analyze health-related quality-of-life (HrQoL) outcomes of patients undergoing transcatheter aortic valve replacement (TAVR) based on data from GARY (German Aortic Valve Registry).

Background: Typically, patients currently referred for and treated by TAVR are elderly with a concomitant variable spectrum of multiple comorbidities, disabilities, and limited life expectancy. Beyond mortality and morbidity, the assessment of HrQoL is of paramount importance not only to guide patient-centered clinical decision-making but also to judge this new treatment modality in this high-risk patient population.

Surveillance of the Incidence of Non-Communicable Diseases (NCDs) with Sparse Resources: A Simulation Study Using Data from a National Diabetes Registry, Denmark, 1995-2004.

We propose two new methods to estimate secular trends in the incidence of a chronic disease from a series of prevalence studies and mortality data. One method is a direct inversion formula, the second method is a least squares estimation. Both methods are validated in a simulation study based on data from a diabetes register.

No adverse effect of outdoor air pollution on HbA1c in children and young adults with type 1 diabetes.

Background: Evidence is growing that air pollutants deteriorate glucose metabolism and insulin sensitivity by oxidative stress and inflammation. This might affect HbA1c levels and insulin requirements in type 1 diabetes. There are no data available on this association.

Development and demonstration of a state model for the estimation of incidence of partly undetected chronic diseases.

Background: Estimation of incidence of the state of undiagnosed chronic disease provides a crucial missing link for the monitoring of chronic disease epidemics and determining the degree to which changes in prevalence are affected or biased by detection.

Methods: We developed a four-part compartment model for undiagnosed cases of irreversible chronic diseases with a preclinical state that precedes the diagnosis. Applicability of the model is tested in a simulation study of a hypothetical chronic disease and using diabetes data from the Health and Retirement Study (HRS).

A comparative study of prevalence-based incidence estimation techniques with application to dementia data in Germany.

Dementia is becoming a major health burden, which is mainly due to the increasing life expectancy in many developed countries. To describe the disease progression of individuals, multistate models are generally appropriate tools. These models allow the individuals to move along a path consisting of a finite number of disease states.

Change rates and prevalence of a dichotomous variable: simulations and applications.

A common modelling approach in public health and epidemiology divides the population under study into compartments containing persons that share the same status. Here we consider a three-state model with the compartments: A, B and Dead. States A and B may be the states of any dichotomous variable, for example, Healthy and Ill, respectively.

A new relation between prevalence and incidence of a chronic disease.

In 1991 Keiding published a relation between the age-specific prevalence and incidence of a chronic disease (in Age-specific incidence and prevalence: a statistical perspective. J. Roy.

Lexis diagram and illness-death model: simulating populations in chronic disease epidemiology.

Chronic diseases impose a tremendous global health problem of the 21st century. Epidemiological and public health models help to gain insight into the distribution and burden of chronic diseases. Moreover, the models may help to plan appropriate interventions against risk factors.

The intermediates take it all: asymptotics of higher criticism statistics and a powerful alternative based on equal local levels.

The higher criticism (HC) statistic, which can be seen as a normalized version of the famous Kolmogorov-Smirnov statistic, has a long history, dating back to the mid seventies. Originally, HC statistics were used in connection with goodness of fit (GOF) tests but they recently gained some attention in the context of testing the global null hypothesis in high dimensional data. The continuing interest for HC seems to be inspired by a series of nice asymptotic properties related to this statistic.

Age- and time-dependent model of the prevalence of non-communicable diseases and application to dementia in Germany.

We derive a partial differential equation (PDE) that models the age-specific prevalence of a disease as a function of the incidence, remission and mortality rates. The main focus is on non-communicable diseases (NCDs), although the PDE is not restricted to NCDs. As an application of the PDE, the number of persons with dementia in Germany until the year 2050 is estimated based on German incidence data and official population projections.

Age of onset in chronic diseases: new method and application to dementia in Germany.

Background: Age of onset is an important outcome to characterize a population with a chronic disease. With respect to social, cognitive, and physical aspects for patients and families, dementia is especially burdensome. In Germany, like in many other countries, it is highly prevalent in the older population and imposes enormous efforts for caregivers and society.

Identification of a multistate continuous-time nonhomogeneous Markov chain model for patients with decreased renal function.

Objectives: Markov chain models are frequently used to study the clinical course of chronic diseases. The aim of this article is to adopt statistical methods to describe the time dynamics of chronically ill patients when 2 kinds of data sets--fully and partially observable data are available.

Model: We propose a 6-state continuous-time Markov chain model for the progression of chronic kidney disease (CKD), where little is known about the transitions between the disease stages.

Deriving age-specific incidence from prevalence with an ordinary differential equation.

This article describes new relationships between the age-specific incidence of, the prevalence of and mortality from a chronic disease. We express these relationships in terms of an ordinary differential equation and form the methodological basis for a novel approach to estimating incidences from age-specific prevalence data. We examine practical aspects of the relationships and a comparison with a known stochastic method in a simulation study.

Effects of photodynamic therapy using topical applied hexylaminolevulinate and methylaminolevulinate upon the integrity of cervical epithelium.

Background And Objective: Cervical intraepithelial neoplasia (CIN) is associated with genital human papillomavirus (HPV) infection and represents the precursor of cervical cancer. Established ablative treatment methods may cause substantial complications in following pregnancies including premature delivery and the birth of low-weight babies. Photodynamic therapy (PDT) of CIN using esters of 5-aminolevulinic acid (5-ALA) represents a promising alternative.

Major tegument protein pp65 of human cytomegalovirus is required for the incorporation of pUL69 and pUL97 into the virus particle and for viral growth in macrophages.

The tegument protein pp65 of human cytomegalovirus (HCMV) represents the major component of mature virus particles. Nevertheless, deletion of pp65 has been shown to have no effects on virus replication and morphogenesis in fibroblasts in vitro. We have studied the HCMV virion composition in the absence of pp65 and viral growth of a pp65 stop mutant in different cell types, including monocyte-derived macrophages.

Distribution of GABA, glycine, and glutamate in neurons of the medulla oblongata and their projections to the midbrain tectum in plethodontid salamanders.

In the medulla oblongata of plethodontid salamanders, GABA-, glycine-, and glutamate-like immunoreactivity (ir) of neurons was studied. Combined tracing and immunohistochemical experiments were performed to analyze the transmitter content of medullary nuclei with reciprocal connections with the tectum mesencephali. The distribution of transmitters differed significantly between rostral and caudal medulla; dual or triple localization of transmitters was present in somata throughout the rostrocaudal extent of the medulla.