[Self-assessment of daily activities using the Duruöz Hand Index-Validation of the German translation]. / Selbstbeurteilung von Alltagsaktivitäten mittels Duruöz-Hand-Index ­ Validierung der deutschen Übersetzung.

BACKGROUND: Independence in activities of daily living depends to a large extent on the upper extremities; however, the instruments widely used in geriatrics to assess self-care abilities do not allow a focus on this body region. In order to map the fluctuating course of hand function-dependent daily living skills with a self-assessment instrument, rheumatologists have developed the Duruöz Hand Index (DHI). OBJECTIVE: The German translation authorized by Duruöz was tested for its applicability in the assessment of geriatric outpatient and day hospital patients and test quality criteria were determined. MATERIAL AND METHODS: Study participants completed the DHI three times. A postgraduate student blinded to the results performed an anamnesis and examination. The geriatric team made an inter-professional assessment of hand function-related daily living skills twice with at least 2­week intervals. RESULTS: Data collection was performed from 16 November 2016 to 27 April 2017 on 101 geriatric day hospital or outpatient patients. Retest reliability was high (0.937), as was internal consistency (Cronbach's α 0.949). Difficulty with activities of daily living correlated more closely with joint mobility (Keitel Index) and fine motor skills (20 cents test) than with hand strength. CONCLUSION: The DHI provides a survey of difficulties with activities of daily living that is focused on the upper extremities. Because about one in three patients required assistance (answering follow-up questions, reading aloud) despite the exclusion of patients with more severely impaired cognition and vision, the examiner should remain present.

Predictions of inter- and intra-lobar deposition patterns of inhaled particles in a five-lobe lung model.

OBJECTIVE: To develop a stochastic five-lobe lung model and to compute particle deposition fractions in the five lobes, considering anatomical as well as ventilatory asymmetry. MATERIALS AND METHODS: The stochastic five-lobe lung model was derived from an existing stochastic model for the whole lung, which implicitly contains information on the lobar airway structure. Differences in lobar ventilation and sequential filling of individual lobes were simulated by a stochastic lobar ventilation model. Deposition fractions of inhaled unit density particles in the five lobes were calculated by an updated version of the Monte Carlo deposition code Inhalation, Deposition, and Exhalation of Aerosols in the Lung (IDEAL). RESULTS: Simulations for defined exposure and breathing conditions revealed that the two lower lobes receive higher deposition and the two upper lobes lower deposition, compared to the average deposition for the whole lung. The resulting inter-lobar distribution of deposition fractions indicated that the non-uniform lung morphometry is the dominating effect, while non-uniform ventilation only slightly enhances the lobar differences. The relation between average lobe-specific deposition fractions and corresponding average values for the whole lung allowed the calculation of lobe-specific deposition weighting factors. DISCUSSION: Comparison with limited deposition measurements for upper vs. lower (U/L) and left vs. right (L/R) lobes revealed overall agreement between experimental and theoretical data. Calculations of the L/R deposition ratio for inhaled aerosol boli confirmed the hypothesis of Möller et al. that the right lung is less able to expand at the end of a breath because of the restrictive position of the liver.

Exposure assessment and associated lung deposition calculations for vehicular exhaust in four metropolitan cities of Pakistan.

Ambient aerosol concentrations along the roadside of metropolitan cities of Pakistan were measured using a Grimm 1.109 dust monitor. Considering the high ambient aerosol concentrations, regional lung deposition of aerosol particles in the human respiratory tract was calculated to assess extent of exposure. Lung deposition was computed in terms of mass concentration and the associated surface area for 12 male traffic wardens using the latest version of the stochastic lung deposition code Inhalation, Deposition, and Exhalation of Aerosols in the Lung. The results have revealed 4 to 10 times higher concentrations than recommended by WHO guidelines. The deposition results derived from the model disclose that extrathoracic deposition is in the range of 22 to 28 % with total lung deposition ranging from 40 to 44 % for the scanned particle window of 0.25-10 µm. Considering an average 8-h shift per day and an average breathing rate of 1.3 m(3) h(-1), it is approximated that in a worker, up to 1.6 mg of inhalable particle mass can deposit per day.

Impact of a priority-setting consultation on doctor-patient agreement after a geriatric assessment: cluster randomised controlled trial in German general practices.

BACKGROUND: General Practitioners (GPs) often have to simultaneously tackle multiple health problems of older patients. A patient-centred process that engages the patient in setting health priorities for treatment is needed. We investigated whether a structured priority-setting consultation reconciles the often-differing doctor-patient views on the importance of problems. DESIGN: Cluster randomised controlled trial with 40 GPs and their 317 consecutively recruited older patients. PROCEDURE: Following a geriatric assessment, patients and doctors independently rated the importance of each uncovered problem. GPs then selected priorities with their patients in a consultation. Trained intervention GPs held a structured consultation and utilised the list of uncovered patient problems with their importance ratings to agree priorities. Untrained control GPs only used the patient's problem list without importance ratings. MAIN OUTCOME: Doctor-patient agreement on independent importance ratings two weeks after the priority-setting consultation. ANALYSIS: Weighted kappa (κw) and multilevel logistic regression model. RESULTS: Intervention GPs and their patients determined mutual priorities for 20% of individual problems. In this process, GPs often succeeded in convincing their patients of the importance of vaccinations, lifestyle and cognitive issues. Likewise, patients convinced their GPs to prioritise their social and functional problems. Further treatment plans ensued in 84% of these priority areas. The regression model adjusting for clusters and baseline characteristics did not demonstrate significant differences in doctor-patient agreement on problems between groups a two weeks later. CONCLUSION: Differing views on the importance of health problems between GPs and older patients were not sustainably reconciled. The special consultation facilitated identification of priority problems for treatment despite differences in perceived importance of problems between patients and GPs. German clinical trials register drks 00000792.

3D-modelling of radon-induced cellular radiobiological effects in bronchial airway bifurcations: direct versus bystander effects.

PURPOSE: The primary objective of this paper was to investigate the distribution of radiation doses and the related biological responses in cells of a central airway bifurcation of the human lung of a hypothetical worker of the New Mexico uranium mines during approximately 12 hours of exposure to short-lived radon progenies. MATERIALS AND METHODS: State-of-the-art computational modelling techniques were applied to simulate the relevant biophysical and biological processes in a central human airway bifurcation. RESULTS: The non-uniform deposition pattern of inhaled radon daughters caused a non-uniform distribution of energy deposition among cells, and of related cell inactivation and cell transformation probabilities. When damage propagation via bystander signalling was assessed, it produced more cell killing and cell transformation events than did direct effects. If bystander signalling was considered, variations of the average probabilities of cell killing and cell transformation were supra-linear over time. CONCLUSIONS: Our results are very sensitive to the radiobiological parameters, derived from in vitro experiments (e.g., range of bystander signalling), applied in this work and suggest that these parameters may not be directly applicable to realistic three-dimensional (3D) epithelium models.

Quantification of airway deposition of intact and fragmented pollens.

Although pollen is one of the most widespread agents that can cause allergy, its airway transport and deposition is far from being fully explored. The objective of this study was to characterize the airway deposition of pollens and to contribute to the debate related to the increasing number of asthma attacks registered after thunderstorms. For the quantification of the deposition of inhaled pollens in the airways computer simulations were performed. Our results demonstrated that smaller and fragmented pollens may penetrate into the thoracic airways and deposit there, supporting the theory that fragmented pollen particles are responsible for the increasing incidence of asthma attacks following thunderstorms. Pollen deposition results also suggest that children are the most exposed to the allergic effects of pollens. Finally, pollens between 0.5 and 20 µm deposit more efficiently in the lung of asthmatics than in the healthy lung, especially in the bronchial region.

Modeling intersubject variability of bronchial doses for inhaled radon progeny.

The main sources of intersubject variations considered in the present study were: (1) size and structure of nasal and oral passages, affecting extrathoracic deposition and, in further consequence, the fraction of the inhaled activity reaching the bronchial region; (2) size and asymmetric branching of the human bronchial airway system, leading to variations of diameters, lengths, branching angles, etc.; (3) respiratory parameters, such as tidal volume, and breathing frequency; (4) mucociliary clearance rates; and (5) thickness of the bronchial epithelium and depth of target cells, related to airway diameters. For the calculation of deposition fractions, retained surface activities, and bronchial doses, parameter values were randomly selected from their corresponding probability density functions, derived from experimental data, by applying Monte Carlo methods. Bronchial doses, expressed in mGy WLM-1, were computed for specific mining conditions, i.e., for defined size distributions, unattached fractions, and physical activities. Resulting bronchial dose distributions could be approximated by lognormal distributions. Geometric standard deviations illustrating intersubject variations ranged from about 2 in the trachea to about 7 in peripheral bronchiolar airways. The major sources of the intersubject variability of bronchial doses for inhaled radon progeny are the asymmetry and variability of the linear airway dimensions, the filtering efficiency of the nasal passages, and the thickness of the bronchial epithelium, while fluctuations of the respiratory parameters and mucociliary clearance rates seem to compensate each other.

Preliminary lung cancer risk assessment of exposure to radon progeny for Transylvania, Romania.

The objective of the present study was to assess the lung cancer risk induced by exposures to radon progeny of people living in some areas of Transylvania, Romania. Indoor radon concentrations were measured in 667 dwellings of Stei area, Cluj, Bistrita-Nasaud, Sibiu, and Alba counties. Measurements were performed using CR-39 track detectors, exposed for a minimum of 3 mo. Average annual radon concentrations were 232, 114, 71, 62, and 161 Bq m for Stei area, Cluj, Bistrita-Nasaud, Sibiu, and Alba, respectively. The linear risk model of Darby was used to simulate the dose-effect relationship and relative lung cancer risk at low doses of alpha particles specific to residential radon exposures. Predicted relative risks at the measured exposure levels, together with information on the total number of reported lung cancer deaths and the number of people living in these regions, enabled us to estimate the fraction of lung cancer cases in each area that is attributable to radon. These percentages are 16.67% for Stei area, 9.09% for Cluj, 5.66% for Bistrita-Nasaud, 4.76% for Sibiu, and 12.28% for Alba county among lifetime non-smokers. Assuming that the smoking rates are similar for the investigated regions (10.72% smokers among men and 5.95% among women), around 64 to 69% of the total number of annual lung cancer deaths, stratified by sex, would be attributed to radon and occur among smoking male population, and around 35 to 44% would be attributed to radon and occur among smoking female population.

Stochastic morphometric model of the BALB/c mouse lung.

The laboratory mouse is often used as a human surrogate in aerosol inhalation studies. Morphometric data on the tracheobronchial geometry of three in situ lung casts of the Balb/c mouse lung produced by the Air Pollution Health Effects Laboratory were analyzed in terms of probability density functions and correlations among the different airway parameters. The results of this statistical analysis reveal significant differences in diameters and branching angles between major and minor progeny branching off from the same parent airway at a given airway bifurcation. Number of bronchial airways generations along a given path, expressed by the termination probability, branching angles, and daughter-to-parent diameter ratios indicate that the location of an airway with defined linear airway dimensions within the lung is more appropriately identified by its diameter (or its parent diameter) than by an assigned generation number. We, therefore, recommend classifying the mouse lung airways by their diameters and not by generation numbers, consistent with our previous analysis of the rather monopodial structure of the rat lung (Koblinger et al., J Aerosol Med 1995;8:7­19; Koblinger and Hofmann, J Aerosol Med 1995;8:21­32). Because of lack of corresponding information on respiratory airways, a partly stochastic symmetric acinar airway model was attached to the tracheobronchial model, in which the number of acinar airways along a given path was randomly selected from a measured acinar volume distribution. The computed distributions of the geometric airway parameters and their correlations will be used for random pathway selection of inhaled particles in subsequent Monte Carlo deposition calculations.

[Monte-Carlo-Model for the aerosol bolus dispersion in the human lung--part 1: theoretical model description and application]. / Monte-Carlo-Modell der Aerosolbolusdispersion in der menschlichen Lunge--Teil 1: Theoretische Modellbeschreibung und Anwendung.

Aerosol bolus dispersion, which has excited enormous interest in lung medicine due to its possible use as an efficient toolfor the non-invasive clinical diagnosis of lung function, was simulated by a Monte Carlo model based on the concept of effective diffusivities and a stochastic lung geometry. The mathematical approach enabled the computation of essential characteristics of the exhaled bolus (half width, standard deviation, skewness, and mode shift) as well as the estimation of their dependence upon the volumetric lung depth (VLD) of the inhaled bolus. Results of the dispersion model generally show a very good correspondence with preliminary published experimental data. Half width and standard deviation of the exhaled bolus increase with VLD according to specific functions, whereas skewness and mode shift are subject to a decrease. While no correlation between bolus dispersion and flow rate could be worked out with the model, dispersion linearly increased with total lung capacity (TLC).

[Monte-Carlo-Model for the aerosol bolus dispersion in the human lung--part 2: model predictions for the diseased lung]. / Monte-Carlo-Modell der Aerosolbolusdispersion in der menschlichen Lunge--Teil 2: Modellvorhersagen für die kranke Lunge.

After a mathematical extension of the existing model for the theoretical description of the aerosol bolus dispersion, the behavior of particle pulses in diseased lung structures was simulated. The geometry usedJbr healthy lungs was modified in two aspects: First, a modelling of possible airway obstructions, which usually occur in patients with chronic bronchitis, chronic asthma or cystic fibrosis, was carried out and, second, a theoretical approximation of the emphysema, being observed in lungs of smokers, but also as an accompanying phenomenon in obstructive diseases, was established. According to the modified model, in lungs with airway obstructions the exhaled bolus exhibited a decreased dispersion with respect to healthy subjects, whereas in emphysematous lungs the respective half-width of the peak was increased. Standard deviation and skewness of the bolus were similarly influenced by the modified lung architecture. A combination of airway obstruction and emphysema caused an extensive compensation of individual dispersion effects, complicating a secure distinction from the healthy lung. According to the model, a special diagnostic value may be assigned to the bolus deposition, showing significant deviations from the normal case for all simulated diseases.

[High utilization of health insurance services by the elderly--analysis of hospital and drug utilization data]. / Vielnutzung von Krankenversicherungsleistungen im Alter--eine Analyse von Krankenhaus- und Arzneimitteldaten.

The present contribution discusses the utilization of the healthcare system by elderly patients in Germany. First, the paper focuses on the detailed characterization of a group of people aged 60 years or more (N = 73,454). Second, the objective is to analyze the data for high utilization of healthcare services by older men and women. The analysis is based on data regularly recorded by a German health insurance agency for the year 2000. High utilization is operationalized by a 10% cutoff for users with the highest number of treatments, highest costs and/or other criteria depending on the respective health service sector. The insured group investigated received approximately 1.4 million prescriptions, producing costs of 42 million E. High utilizers account for 32% of all prescriptions and 44% of the costs, respectively. At the same time, the age groups with the highest prescription rates do not cause the highest costs: So the relationship between age and prescription drug expenses as well as between age and prescription rates does not display an arithmetically increasing pattern. Within the timeframe investigated 26,000 hospital treatments were accounted for by 21.75% of the elderly under research. In total, they caused expenses of 88 million E. High utilization in the hospital sector was operationalized by four criteria. Sex- and age-specific analysis of high utilization of hospital treatment revealed that the four different criteria apply to different insured groups. In summary, the high utilization of healthcare services appears to be a multidimensional phenomenon.

Exposure assessment of diesel bus emissions.

The goal of this study was to measure ultrafine particle concentrations with diameters less than 1 mum emitted by diesel buses and to assess resulting human exposure levels. The study was conducted at the Woolloongabba Busway station in Brisbane, Australia in the winter months of 2002 during which temperature inversions frequently occurred. Most buses that utilize the station are fuelled by diesel, the exhaust of which contains a significant quantity of particle matter. Passengers waiting at the station are exposed to these particles emitted from the buses. During the course of this study, passenger census was conducted, based on video surveillance, yielding person-by-person waiting time data. Furthermore, a bus census revealed accurate information about the total number of diesel versus Compressed Natural Gas (CNG) powered buses. Background (outside of the bus station) and platform measurements of ultrafine particulate number size distributions were made to determine ambient aerosol concentrations. Particle number exposure concentration ranges from 10 and 40 to 60% of bus related exhaust fumes. This changes dramatically when considering the particle mass exposure concentration, where most passengers are exposed to about 50 to 80% of exhaust fumes. The obtained data can be very significant for comparison with similar work of this type because it is shown in previous studies that exhaust emissions causes cancer in laboratory animals. It was assumed that significant differences between platform and background distributions were due to bus emissions which, combined with passenger waiting times, yielded an estimate of passenger exposure to ultrafine particles from diesel buses. From an exposure point of view, the Busway station analyzed resembles a street canyon. Although the detected exhaust particle concentration at the outbound platform is found to be in the picogram range, exposure increases with the time passengers spend on the platform along with their breathing frequency.

CFD as a tool in risk assessment of inhaled radon progenies.

During the last decade, computational fluid dynamics techniques proved to be a powerful tool in the modelling of biological processes and the design of biomedical devices. In this work, a computational fluid dynamics method was applied to model the transport of inhaled air and radioactive particles within the human respiratory tract. A finite volume numerical approach was used to compute the flow field characteristics and particle trajectories in the lumen of the first five airway generations of the human tracheobronchial tree, leading to the right upper lobe. The computations were performed for breathing and exposure conditions characteristic of uranium mines and homes. Primary radon daughter deposition patterns and energy distributions were computed, exhibiting highly inhomogeneous particle and energy deposition patterns. The results of the present modelling effort can serve as input data in lung cancer risk analysis.

[Stochastic model for the spatial visualization of particle-deposition patterns in the lung and their significance in lung medicine]. / Stochastisches Modell zur räumlichen Visualisierung von Teilchendepositionsmustern in der Lunge und ihre Bedeutung in der Lungenmedizin.

The present paper provides a detailed description of an extension of the Monte Carlo computer model IDEAL, which enables the generation of spatial particle deposition patterns in the human lung. Randomly determined particle trajectories are transformed to a Cartesian coordinate system within which the orientation of the trachea corresponds to the z-direction. At the same time, the determination of particle deposition sites is carried out by application of a grid composed of specific volume elements (voxel). The calculation of particle deposition are based on the physical mechanisms of Brownian diffusion, sedimentation, and inertial impaction. After their storage in a matrix, the deposition data are subject to graphical processing. This allows the presentation of spatial particle distribution patterns (3d-density plots) and of the lung surface itself as well as the generation of two-dimensional distributions by sectioning the three-dimensional structures at pre-defined positions. The results of different model simulations (variation of particle size and breathing conditions) are discussed in detail.

The effect of morphological variability on surface deposition densities of inhaled particles in human bronchial and acinar airways.

Deposition fractions in human airway generations were computed with a stochastic deposition model, which is based on a randomly, asymmetrically dividing lung morphology, applying Monte Carlo techniques. Corresponding uncorrelated surface deposition densities were obtained by dividing the average deposition fraction in a given generation by the average total surface area of that generation. In order to consider the statistical correlation between deposition probability and linear airway dimensions in each airway, correlated surface deposition densities were calculated by dividing the deposition fraction in a randomly selected bronchial or acinar airway by the surface area of that airway and by the total number of bronchial or acinar airways in that generation. Average surface deposition densities are relatively constant throughout bronchial airway generations, while average acinar surface deposition densities exhibit a distinct decrease with rising penetration into the acinar region. Due to the correlation between deposition fraction and surface area in a given airway generation, average correlated surface deposition densities are consistently higher than average uncorrelated densities, particularly in the acinar region, where differences can be as high as a few orders of magnitude. Already significant statistical fluctuations of the deposition fractions in individual airway generations are even exacerbated for surface deposition densities, with coefficients of variation about twice as high as for correlated deposition fractions.