Intradural extramedullary granular cell tumour in a cat.

A 7-year-old domestic shorthair cat was evaluated for progressive paraparesis, inability to jump, a paralysed tail and inability to void the bladder. Neurologic examination was consistent with a L4-S3 localisation. Survey radiographs of the lumbar vertebral column revealed L4-L7 vertebral body remodelling. A pre-contrast T1-weighted hyperintense, diffusely enhancing intradural lesion extending from L4 to S1 vertebral bodies was detected by MRI. Large, mesenchymal, round-to-polygonal cells arranged in nests or sheets were found on histologic examination at post mortem. These cells were characterised by abundant intracytoplasmic PAS-positive, diastase-resistant granules and positive immunoexpression of vimentin, S-100, neuron-specific enolase and desmin. This is the first report of a spinal granular cell tumour in a cat.

Major trauma critical pathway: preliminary results from the monitoring system in the regional network and in a hub center in Rome metropolitan area.

OBJECTIVE: The aim of this study is to collect the two years' data regarding the Integrated Trauma Management System (SIAT) by capturing the activity of its three Hubs in the Italian Lazio Region and test the performance of one of the Hubs' (Fondazione Policlinico Universitario A. Gemelli - IRCCS, FPG -IRCCS) Major Trauma Clinical Pathway's (MTCP) monitoring system, introducing the preliminary results through volume, process and outcome indicators. MATERIALS AND METHODS: A retrospective analysis on SIAT was conducted on years 2016 to 2018, by collecting outcome and timeliness indicators through the Lazio Informative System whereas the MTCP was monitored through set of indicators from the FPG - IRCCS Informative System belonging to randomly selected clinical records of the established period. RESULTS: Hubs managed 11.3% of the 998,240 patients admitted in SIAT. All patients eligible for MTCP were "Flagged", and 83% underwent a CT within 2 hours; intra-hospital mortality was 13% whereas readmission rates 16.9%. CONCLUSIONS: SIAT converges the most severe patients to its Hubs. The MTCP monitoring system was able to measure a total of 9 out of 13 indicators from the original panel. This research may serve as a departing point to conduct a pre-post analysis on the performance of the MTCP.

Nonpenetrating deep sclerectomy with reticulated hyaluronic acid implant versus punch trabeculectomy: a prospective clinical trial.

PURPOSE: To compare the intraocular pressure (IOP)-lowering effect and complication rate of nonpenetrating deep sclerectomy (NPDS) with reticulated hyaluronic acid (SK-GEL) scleral implant versus traditional punch trabeculectomy (PT) in the management of primary open angle glaucoma (POAG). METHODS: Prospective, randomized comparative study including 93 patients with uncontrolled POAG. Group 1 (43 eyes) underwent NPDS with SK-GEL scleral implant; Group 2 (50 eyes) underwent PT. Mitomycin C (0.2 mg/mL) was applied intraoperatively in both techniques. Study follow-up evaluations were conducted at 36 and 48 months. Complete success indicated the achievement of the target IOP without antiglaucoma medications, while qualified success indicated the same goal with medications. These categories were assessed at two target IOP levels, <21 mmHg and <18 mmHg. RESULTS: At 36 months for complete and qualified success with a <21 and <18 mmHg target IOP, no significant differences were noted between the two groups. At 48 months postprocedure when a <21 mmHg IOP target was considered, the rate of eyes that achieved complete success was 51.1% in the NPDS group versus 72% in the PT group (p<0.05). As for the <18 mmHg IOP target, the rate of eyes that achieved complete success was 32.5% in the NPDS group versus 44% in the PT group (p<0.05). Complications occurred significantly more frequently after PT than after NPDS. CONCLUSIONS: The IOP-lowering effects of the two procedures were comparable at 36 months. At 48 months PT showed a significantly higher rate of complete success compared with NPDS. Complications were more frequent after PT than after NPDS.

Engraftment capacity of mesenchymal cells following hematopoietic stem cell transplantation in patients receiving reduced-intensity conditioning regimen.

The engraftment ability of mesenchymal cells was investigated in 26 patients receiving allogeneic transplantation from HLA-identical siblings with reduced-intensity conditioning (RIC). The stem cell source was bone marrow (BM) in eight patients and G-CSF-mobilized peripheral blood hematopoietic cells in 18 cases. A total of 32 patients engrafted very quickly and the chimerism evaluation (both on myeloid and on lymphoid subsets) showed that they were full donor by day 60. At the time of the study they were in complete hematological remission and displayed a full donor hematopoiesis. Two patients showed early disease progression while one did not engraft. Forty-eight out-marrow samples harvested from the 26 patients generated a marrow stromal layer adequate for the chimerism evaluation. Monocyte-macrophage contamination of marrow stromal layers was always reduced below 2% by repeated trypsinizations and treatment with the leucyl-leucine (leu-leu) methyl ester. The chimerism evaluation was performed by PCR analysis of STRs microsatellites and the amelogenin locus, by using capillary electrophoresis (CE) and by FISH analysis in case of the sex mismatch. In eight patients, a partial donor origin of stromal cells was shown (7-86% cells of donor). The source of hematopoietic cells was BM in three patients and mobilized peripheral blood in the other five.

Prevalence and Risk Factors for Presumptive Ascending/Descending Myelomalacia in Dogs after Thoracolumbar Intervertebral Disk Herniation.

BACKGROUND: Ascending/descending myelomalacia (ADMM) is a severe complication of thoracolumbar intervertebral disk herniation (TL-IVDH) in dogs. HYPOTHESIS/OBJECTIVES: To investigate the prevalence and risk factors for ADMM in nonambulatory dogs with surgically treated TL-IVDH. ANIMALS: Six-hundred and fifty-two client-owned dogs evaluated for TL-IVDH that underwent decompressive spinal surgery. METHODS: Retrospective medical record review from February 2007 through December 2015. RESULTS: Thirteen dogs developed ADMM, with an overall prevalence of 2.0%. The prevalence of ADMM was 0% in dogs with neurological signs graded 1 or 2 at admission or before magnetic resonance imaging (MRI) or surgical procedures, 0.6% in dogs with neurological signs graded 3, 2.7% in dogs with neurological signs graded 4, and 14.5% in dogs with neurological signs graded 5. Age (<5.8 years), neurological status (grade 5), site of disk herniation (L5-L6), duration of clinical signs before becoming nonambulatory (<24 hours), detection of intramedullary T2-weighted (T2W) hyperintensity, and a T2 length ratio >4.57 were significant risk factors in the univariate analysis for development of ADMM. CONCLUSIONS AND CLINICAL IMPORTANCE: The factors identified in this study may be useful for the prediction of ADMM. Multicenter studies with a higher number of dogs with ADMM are required to confirm these data.

MR Micro-Neurography and a Segmentation Protocol Applied to Diabetic Neuropathy.

The aim of this study was to assess with MRI morphometric ultrastructural changes in nerves affected by diabetic peripheral neuropathy (DPN). We used an MR micro-neurography imaging protocol and a semiautomated technique of tissue segmentation to visualize and measure the volume of internal nerve components, such as the epineurium and nerve fascicles. The tibial nerves of 16 patients affected by DPN and of 15 healthy volunteers were imaged. Nerves volume (NV), fascicles volume (FV), fascicles to nerve ratio (FNR), and nerves cross-sectional areas (CSA) were obtained. In patients with DPN the NV was increased and the FNR was decreased, as a result of an increase of the epineurium (FNR in diabetic neuropathy 0,665; in controls 0,699, p = 0,040). CSA was increased in subjects with DPN (12,84 mm2 versus 10,22 mm2, p = 0,003). The FV was increased in patients with moderate to severe DPN. We have demonstrated structural changes occurring in nerves affected by DPN, which otherwise are assessable only with an invasive biopsy. MR micro-neurography appears to be suitable for the study of microscopic changes in tibial nerves of diabetic patients.

Investigating regional differences in short-term effects of air pollution on daily mortality in the APHEA project: a sensitivity analysis for controlling long-term trends and seasonality.

Short-term effects of air pollution on daily mortality in eight western and five central-eastern European countries have been reported previously, as part of the APHEA project. One intriguing finding was that the effects were lower in central-eastern European cities. The analysis used sinusoidal terms for seasonal control and polynomial terms for meteorologic variables, but this is a more rigid approach than the currently accepted method, which uses generalized additive models (GAM). We therefore reanalyzed the original data to examine the sensitivity of the results to the statistical model. The data were identical to those used in the earlier analyses. The outcome was the daily total number of deaths, and the pollutants analyzed were black smoke (BS) and sulfur dioxide (SO(2)). The analyses were restricted to days with pollutant concentration < 200 microg/m(3) and < 150 microg/m(3) alternately. We used Poisson regression in a GAM model, and combined individual city regression coefficients using fixed and random-effect models. An increase in BS by 50 microg/m(3) was associated with a 2.2% and 3.1% increase in mortality when analysis was restricted to days < 200 microg/m(3) and < 150 microg/m(3), respectively. The corresponding figures were 5.0% and 5.6% for a similar increase in SO(2). These estimates are larger than the ones published previously: by 69% for BS and 55% for SO(2). The increase occurred only in central-eastern European cities. The ratio of western to central-eastern cities for estimates was reduced to 1.3 for BS (previously 4.8) and 2.6 for SO(2) (previously 4.4). We conclude that part of the heterogeneity in the estimates of air pollution effects between western and central-eastern cities reported in previous publications was caused by the statistical approach used and the inclusion of days with pollutant levels above 150 microg/m(3). However, these results must be investigated further.

Growth and developmental retardation, ocular ptosis, cardiac defect, and anal atresia: confirmation of the ROCA-Wiedemann syndrome.

We report on a girl with growth and mental retardation, peculiar face with ptosis, epicanthus, broad nasal bridge, low-set and abnormal ears, cleft uvula, congenital heart defect, and anal atresia. A similar condition was reported previously by Wiedemann et al. [1982: An atlas of characteristic syndromes: a visual aid to diagnosis, 2nd ed. p 114-115]. We confirm the existence of this condition that, although similar to Ohdo syndrome, seems to be an independent clinical entity. We propose that, based on the principal clinical manifestations, this condition should be identified with the acronym ROCA (retardation of growth and development, ocular ptosis, cardiac defect, and anal atresia).

Opitz C trigonocephaly syndrome and midline brain anomalies.

We describe a child with trigonocephaly, strabismus, upslanting palpebral fissures, nasal bridge hypoplasia, hypertrophic alveolar ridges and large gingivo-labial frenula, short neck, hip "dysplasia," equinovarus deformities, cryptorchidism, atrial septal defect ostium secundum, and severe mental retardation, findings consistent with C syndrome. The patient also had a Dandy-Walker malformation, complete callosal agenesis, and occipital meningocele. These structural defects are independent of the premature closure of the metopic suture, and confirm that midline brain anomalies are part of C syndrome. The hypothesis that the basic developmental defect in this syndrome primarily affects the midline field is supported by the concomitance of other anomalies, such as conotruncal heart defects, omphalocele, and genital anomalies.

Severe form of Freeman-Sheldon syndrome associated with brain anomalies and hearing loss.

We describe a child with whistling face and multiple contractures, including ulnar deviation of fingers, compatible with a diagnosis of Freeman-Sheldon syndrome (FSS). This patient also presented severe hypertonicity, multiple episodes of pneumonia, difficulty in swallowing, and poor weight gain, which are characteristic of the most severe cases of FSS. A brain CT scan showed cerebellar and brainstem atrophy. Auditory brainstem responses were absent. The child died at 5 months of respiratory failure. This case suggests the possibility that, especially in the most severe forms, brain abnormalities may be responsible for some of the clinical manifestations of this syndrome, i.e., respiratory problems, difficulty in swallowing and severe hypertonicity. We assume that there is more than one pathogenetic mechanism (muscular, skeletal, and neurological) underlying FSS, which, together with the genetic heterogeneity and the wide range of clinical symptoms leads us to suggest that it is more appropriate to speak of a Freeman-Sheldon spectrum rather than syndrome and that thorough investigation for CNS and auditory abnormalities should be part of the initial work-up of these patients.

Epidemiological significance of microbiological pollution criteria for river recreational waters.

A retrospective follow-up study was conducted during the summer of 1986 in the French Ardèche basin in order to assess the relationship between swimming-related morbidity and the bacteriological quality of the recreational water. 5737 tourists in eight holiday camps were questioned as to the occurrence of illness and their bathing habits during the week preceding the interviews. The rate-ratio contrasting swimmers and non-swimmers for total morbidity is 2.1 (1.8-2.4) = 95% confidence interval); gastrointestinal illness is the major type of morbidity and differs significantly between the two groups (RR = 2.4 (1.9-3.0) for total gastrointestinal cases; RR = 2.3 (1.7-3.2) for 'objective' gastrointestinal cases). Faecal streptococci (FS) are best correlated to gastrointestinal morbidity, using direct linear regression models. Faecal coliforms (FC) are not as good predictors of the risk. The concentration of faecal streptococci above which the 'objective' gastrointestinal morbidity among bathers is significantly greater than among non-bathers is 20 FS/100 ml. Swimmers suffer skin ailments much more frequently than non-swimmers (RR = 3.7 (2.4-5.7]; although the relationship may be artefactual, this type of morbidity is well correlated with the concentration of faecal coliforms, aeromonas and pseudomonas. This study provides epidemiological data on which to base microbiological standards for river recreational waters dependent on what might be considered as an 'acceptable' risk.

Short term effects of air pollution on mortality in the city of Lyon, France, 1985-90.

OBJECTIVE: The short term association between daily mortality and ambient air pollution in the city of Lyon, France (population, 410,000) between 1985 and 1990 was assessed using time series analysis. DESIGN: This study followed the standardised design and statistical analysis (Poisson regression) that characterise the APHEA project. METHODS: Four categories of cause of death were studied: total (minus external causes), respiratory, cardiovascular, and digestive causes (as a control condition). RESULTS: No association was found with any cause of death for nitrogen dioxide (NO2) and ozone (O3), nor, for any pollutant, for digestive conditions. Sulphur dioxide (SO2) and, to a much lesser degree, suspended particles (PM13), were significantly related to mortality from respiratory and cardiovascular conditions. The relative risk (RR) of respiratory deaths associated with a 50 micrograms/m3 increment of mean daily SO2 over the whole period was 1.22 (95% CI 1.05, 1.40); the RR for cardiovascular deaths was 1.54 (1.22, 1.96). The corresponding RRs for PM13 were 1.04 (1.00, 1.09) for respiratory mortality and 1.04 (0.99, 1.10) for cardiovascular deaths. CONCLUSIONS: The effects of particulates were slightly increased during the cold season. When particulates concentrations were greater than 60 micrograms/m3, the joint SO2 effect was increased, suggesting some interaction between the two pollution indicators. These results agree with other studies showing an association between particulate pollution and daily mortality; however, they also suggest the noxious effect of SO2.

Huge progression of diabetes prevalence and incidence among dialysed patients in mainland France and overseas French territories. A second national survey six years apart. (UREMIDIAB 2 study).

In 1989, we conducted a survey (UREMIDIAB) on the prevalence of diabetes among the population on Renal Replacement Therapy (RRT) in Mainland France (MF), the lowest of the developed countries (6.9%) with a North-South gradient (higher prevalence in the North). This highlighted a possible (genetical or nutritional) "new french paradox" in mainland France populations. In 1992 we conducted a similar study in the french (mainly non caucasian) overseas territories (OT) hosting 3.2% of the total french population, and observed a prevalence of diabetes in RRT of 22.9%. The frequency of diabetes mellitus as a cause of ESRD increasing worldwide, we conducted a second survey in year 1995, in MF and the OT. This study, UREMIDIAB 2, included all of the 244 french dialysis centers. A "Center file" allowed us to determine the prevalence and incidence of diabetes in the french RRT population, (response rate 73%). Then a "Patient medical file" (response rate 64.8% for MF and 91% for the OT) provided detailed informations: type of diabetes (type 1 or 2), etiology of nephropathy, status of diabetic complications, family's geographic origin of the patient. In MF the prevalence of diabetics in RRT doubled within 6 years: 13.04% vs 6.9%, the incidence reached 15.7%. In the OT the prevalence and the incidence reached 25.7% and 35.6%, respectively. Type 2 diabetes represented 87% and 93% of the RRT diabetics in MF and the OT, respectively. Diabetic nephropathy was considered as the cause of renal failure in 91.3% of type 1 and 57.5% of type 2 diabetics under dialysis. We found: 14.7% of myocardial infarction, 12.7% of cerebral strokes, 17.6% of amputations (extreme 37% in some OT centers) among this diabetic RRT population. A North-East (higher prevalence) South-West (lower) gradient was confirmed. We conclude that, while an unusual low prevalence (< or = 13%) of diabetics under dialysis persists in some parts of Mainland France, the total prevalence has been doubled within 6 years (1989/95) and that in Overseas Territories, hosting similar mixed blood populations than USA (afro-caribbeans, asians, indians, micronesians and metis), the high incidence of diabetes in RRT has reached the US levels during the same period.

Classification of diabetes in patients with end-stage renal disease. Validation of clinical criteria according to fasting plasma C-peptide.

An epidemiologic study of end-stage diabetic nephropathy in France (Uremidiab) was performed, aiming to establish the prevalence of both types of diabetes in dialysis patients. Because discrimination between type I and type II diabetes remains mostly clinical, our aim was to evaluate what the most fitted clinical criteria were. We studied 494 hemodialyzed diabetic patients. A first classification (Cn) was offered by the nephrologist. Clinical data of 472 patients (22 patients of the 494 have been excluded) were then collected with a standardized questionnaire, allowing one diabetologist of us to establish the diagnosis of type of diabetes (classification Cd). Plasma C-peptide at this stage of the disease was expected to be very discriminative, measured in 88 patients and defined classification Ccp (< or = 0.6 ng/ml = "negative C-peptide" = type I, > 0.6 ng/ml = "positive C-peptide" = type II). Classification Cd observed 98 type I and 374 type II diabetes. Cn overestimated type I diabetes, 37% of type II diabetes being misclassified because insulin-treated. Classification Ccp observed 74 positive C-peptide patients, classified as type II, among whom 45 were insulin-treated. Only 3 patients were discordant for classification Cd and Ccp. Predictive value of "negative C-peptide" and "positive C-peptide" were 100% and 96% respectively. Multiple regression analysis of the Ccp classification was performed with the clinical criteria and showed very significant correlation with: age at the time of diagnosis of diabetes (AGE), maximal body mass index ever reached (BMI MAX) and delay between diagnosis and consistent insulin use (DI).(ABSTRACT TRUNCATED AT 250 WORDS)

Health effects costs of particulate air pollution.

We conducted a cross-sectional study in December 1994 in three metropolitan areas of the Rhone-Alpes region in France (Lyon, Grenoble, and Chambéry; total number of inhabitants = 970,000) to assess the medical costs resulting from exposure to particulate air pollution. Probability samples of the general population (508 families, 1265 subjects) and of the physicians (395) and 13 hospital respiratory care and emergency units in the study area provided data on the prevalence of respiratory disorders and on medical care usage. Measurements from air-quality monitoring networks were used to ascribe a fraction of the respiratory morbidity to the ambient air particle concentrations present during the study period, on the basis of attributable risk estimates drawn from recent meta-analyses. The medical care usage and absenteeism related to respiratory disorders were converted into direct and indirect medical and social costs by use of a "cost of illness" approach. These costs were extrapolated to annual costs of disease attributable to particulate pollution in 1994, using daily values of air pollution. The average particulate concentrations during the study period were moderate (39, 41, and 10 micrograms/m3 in the three cities), yielding attributable fractions that ranged between 0.6% and 13.8% according to the health condition and to the city. Three hundred ninety-five subjects reported respiratory symptoms (prevalence, 31.2%) during the study period; 1182 patients visited a doctor and 158 used hospital services. The extrapolated annual estimates of the attributable cost of respiratory diseases for a population of 1 million range between 79 and 135 million French francs (FF) (20th and 80th percentiles of the cost distribution, after a Monte Carlo simulation, respectively; 50th percentile, 107 x 10(6) FF [16.3 x 10(6) Euros]). Over-the counter drug consumption represents the largest cost item (approximately 44% of total costs), followed by wage losses (38%). Hospital expenditures amount to a low percentage of total costs (about 5%) because most respiratory disorders do not require hospital care. Mortality was not considered in this study. Most of these costs occur at relatively low levels of air pollution (67% of the total annual costs are incurred during days with particle concentrations lower than 50 micrograms/m3). Such substantial figures are useful for assessing the social impacts of air pollution and for evaluating the cost efficiency of abatement policies.

[POLAIR: software and methodological guide for the epidemiological investigation of a point source atmospheric pollution]. / POLAIR: logiciel et guide méthodologique pour l'investigation épidémiologique d'une pollution atmosphérique ponctuelle.

The POLAIR software is designed to guide the user along a methodological approach to assess the health consequences of an accidental or chronic point source atmospheric pollution. This article presents the two components of the software, i.e. the gaussian modelization of the pollution contour lines on the territory around the emission source that allows to calculate an exposure index for every individual with a space-time ponderation factor, and the implementation, by using the EPI-INFO software, of a case-control or historical cohort epidemiological study among the population living in the vicinity of the source. Standardized questionnaires for the collection of data in the field are proposed, and the steps of the data analysis are commented upon, on the basis of an illustrative example.

[Meta-analysis and dose-response functions of air pollution respiratory effects]. / Méta-analyse et fonctions dose-réponse des effets respiratoires de la pollution atmosphérique.

A Meta-analysis was conducted on 107 original epidemiological papers published between 1980 and 1993 on the respiratory health impact of suspended particles, sulfur dioxide, ozone and nitrogen dioxide. These are the usual air quality indicators that are monitored in urban ambient air. The range of exposures that were studied (averages and 90th percentiles are respectively up to 88, 83, 124 and 53 mu/m3 (averages) and 180, 147, 234 and 131 micrograms/m3 (90th percentile) for each of the four pollution indicators) allowed assessment of dose-response functions for irritative pulmonary conditions (cough and/or asthma episodes) and respiratory function (FEVI and peak expiratory flow). The dose-response functions seem linear in the range of observed concentrations, with nitrogen dioxide showing the least consistent association across different health indicators. When applied to exposures measured as a 100 micrograms/m3 increase of pollutant's concentrations compared to low background values, the average relative risks of airway irritation (cough and/or asthma épisodes) range, according to the pollutant, from 1.08 to 1.47; average relative decreases of respiratory function amount to 1.1 to 2.2%. The effects are most often stronger among young subjects. The results of this study, when applied to air pollution concentrations in the range of values that were observed in this study, should foster health risk assessment studies in places where population air pollution exposures are available.

[Evaluation of microbial indicators of health risk related to river swimming places]. / Evaluation des indicateurs microbiens du risque sanitaire lié aux baignades en rivière.

A retrospective follow-up study was conducted among 5,737 tourists in 8 holiday camps, during the 1986 summer, in the Ardèche river basin, in order to study the relationship between the bacteriological water quality and the morbidity that occurred to swimmers. Total morbidity was more frequent among bathers than non-bathers (Risk Ratio = 1.7 [95% confidence interval = 1.4-2.1]); gastro-intestinal illness was the major type of morbidity (RR = 2.8 [1.8-4.4] for "objective gastro-intestinal diseases). After screening for the germs that were best correlated with gastro-intestinal and skin diseases, using simple linear regression, logistic regression models allowed confirmation that fecal streptococci best predicted gastro-intestinal morbidity; it significantly exceeded the risk observed among non-bathers above a concentration of 20 SF/100 ml ("objective" gastro-intestinal morbidity). The relationship with fecal coliforms was less clear. However, they are good indicators of skin diseases risk. These results should help re-evaluation of the current microbiological standards concerning recreational waters.

Relationships between nitrogen dioxide personal exposure and ambient air monitoring measurements among children in three French metropolitan areas: VESTA study.

In epidemiological studies, investigators have routinely used ambient air concentrations, measured by air-quality monitoring networks, to assess exposure of subjects. When there is great spatial variability of ambient air concentrations or when there are specific indoor exposures, this approach may yield substantial exposure misclassification and distort the associations between exposure and the health endpoints of interest. In 3 French metropolitan areas, the cross-sectional relationships between 48 hr of nitrogen dioxide personal exposure of 73 children and the corresponding 48-hr background ambient air concentrations were analyzed. The crude correlation between ambient air concentrations and personal exposures was poor in all cities (r2 = .009 for Grenoble, r2 = .04 for Toulouse, and r2 = .02 for Paris). These correlations were improved when the authors took into account other ambient air or indoor air sources of nitrogen dioxide emissions (the corresponding multiple linear regression, r2, increased to .43 in Grenoble, .50 in Toulouse, and .37 in Paris). The main variables that explained personal exposures were an index of traffic intensity and proximity and use of a gas cooker at home. The results of this study confirm that ambient air-monitoring site measurements are poor predictors of personal exposure. Investigators should carefully characterize the proximity of roads occupied by dense traffic to the home/school as well as indoor sources of nitric oxide emissions; both of these careful characterizations will assist researchers in the prediction of personal exposure in epidemiological studies.

Short-term effects of air pollution on hospital admissions of respiratory diseases in Europe: a quantitative summary of APHEA study results. Air Pollution and Health: a European Approach.

The Air Pollution and Health: a European Approach (APHEA) project is a coordinated study of the short-term effects of air pollution on mortality and hospital admissions. Five West European cities (i.e., London, Amsterdam, Rotterdam, Paris, Milano) contributed several years of hospital admissions data for all respiratory causes. In the current study, the authors describe the results obtained from the quantitative pooling (meta-analysis) of local analyses. The diagnostic group was defined by ICD 460-519. The age groups studied were 15-64 y (i.e., adults) and 65+ y (elderly). The air pollutants studied were sulfur dioxide; particles (i.e., Black Smoke or total suspended particles); ozone; and nitrogen dioxide. The pollutants were obtained from existing fixed-site monitors in a standardized manner. We used Poisson models and standardized confounder models to examine the associations between daily hospital admissions and air pollution. We conducted quantitative pooling by calculating the weighted means of local regression coefficients. We used a fixed-effects model when no heterogeneity could be detected; otherwise, we used a random-effects model. When possible, the authors investigated the factors correlated with heterogeneity. The most consistent and strong finding was a significant increase of daily admissions for respiratory diseases (adults and elderly) with elevated levels of ozone. This finding was stronger in the elderly, had a rather immediate effect (same or next day), and was homogeneous over cities. The elderly were affected more during the warm season. The Sulfur dioxide daily mean was available in all cities, and it was not associated consistently with an adverse effect. Effects were present in areas in which more than one station was used in the assessment of daily exposure. Some significant associations were observed, although no conclusion that related to an overall particle effect could be drawn. The effect of Black Smoke was significantly stronger with high nitrogen dioxide levels on the same day, but nitrogen dioxide itself was not associated with admissions. The ozone results were in good agreement with the results of similar U.S. studies. The coherence of the results of this study and other results gained under different conditions strengthens the argument for causality.