Biomedical subjects

Christian Schindler

Publications and source records attributed to Christian Schindler.

At least 19 recordsLinked to original sources

PubMed2007

Glutathione S-transferase genotypes modify lung function decline in the general population: SAPALDIA cohort study.

BACKGROUND: Understanding the environmental and genetic risk factors of accelerated lung function decline in the general population is a first step in a prevention strategy against the worldwide increasing respiratory pathology of chronic obstructive pulmonary disease (COPD). Deficiency in antioxidative and detoxifying Glutathione S-transferase (GST) gene has been associated with poorer lung function in children, smokers and patients with respiratory diseases. In the present study, we assessed whether low activity variants in GST genes are also associated with accelerated lung function decline in the general adult population. METHODS: We examined with multiple regression analysis the association of polymorphisms in GSTM1, GSTT1 and GSTP1 genes with annual decline in FEV1, FVC, and FEF25-75 during 11 years of follow-up in 4686 subjects of the prospective SAPALDIA cohort representative of the Swiss general population. Effect modification by smoking, gender, bronchial hyperresponisveness and age was studied. RESULTS: The associations of GST genotypes with FEV1, FVC, and FEF25-75 were comparable in direction, but most consistent for FEV1. GSTT1 homozygous gene deletion alone or in combination with GSTM1 homozygous gene deletion was associated with excess decline in FEV1 in men, but not women, irrespective of smoking status. The additional mean annual decline in FEV1 in men with GSTT1 and concurrent GSTM1 gene deletion was -8.3 ml/yr (95% confidence interval: -12.6 to -3.9) relative to men without these gene deletions. The GSTT1 effect on the FEV1 decline comparable to the observed difference in FEV1 decline between never and persistent smoking men. Effect modification by gender was statistically significant. CONCLUSION: Our results suggest that genetic GSTT1 deficiency is a prevalent and strong determinant of accelerated lung function decline in the male general population.

Adult↗

PubMed2006

NF-kappaB regulation of endothelial cell function during LPS-induced toxemia and cancer.

The transcription factor NF-kappaB is an important regulator of homeostatic growth and inflammation. Although gene-targeting studies have revealed important roles for NF-kappaB, they have been complicated by component redundancy and lethal phenotypes. To examine the role of NF-kappaB in endothelial tissues, Tie2 promoter/enhancer-IkappaBalpha(S32A/S36A) transgenic mice were generated. These mice grew normally but exhibited enhanced sensitivity to LPS-induced toxemia, notable for an increase in vascular permeability and apoptosis. Moreover, B16-BL6 tumors grew significantly more aggressively in transgenic mice, underscoring a new role for NF-kappaB in the homeostatic response to cancer. Tumor vasculature in transgenic mice was extensive and disorganized. This correlated with a marked loss in tight junction formation and suggests that NF-kappaB plays an important role in the maintenance of vascular integrity and response to stress.

Animals↗

PubMed2006

Living near main streets and respiratory symptoms in adults: the Swiss Cohort Study on Air Pollution and Lung Diseases in Adults.

The Swiss Cohort Study on Air Pollution and Lung Diseases in Adults (SAPALDIA), conducted in 1991 (SAPALDIA 1) in eight areas among 9,651 randomly selected adults aged 18-60 years, reported associations among the prevalence of respiratory symptoms, nitrogen dioxide, and particles with an aerodynamic diameter of less than 10 microg/m3. Later, 8,047 subjects reenrolled in 2002 (SAPALDIA 2). The effects of individually assigned traffic exposures on reported respiratory symptoms were estimated, while controlling for socioeconomic and exposure- and health-related factors. The risk of attacks of breathlessness increased for all subjects by 13% (95% confidence interval: 3, 24) per 500-m increment in the length of main street segments within 200 m of the home and decreased in never smokers by 12% (95% confidence interval: 0, 22) per 100-m increment in distance from home to a main street. Living within 20 m of a main street increased the risks of regular phlegm by 15% (95% confidence interval: 0, 31) and wheezing with breathing problems by 34% (95% confidence interval: 0, 79) in never smokers. In 2002, the effects related to road distance were different from those in 1991, which could be due to changes in the traffic pollution mixture. These findings among a general population provide strong confirmation that living near busy streets leads to adverse respiratory health effects.

Adolescent↗

PubMed2006

Respiratory effects of environmental tobacco exposure are enhanced by bronchial hyperreactivity.

RATIONALE: Exposure to environmental tobacco smoke (ETS) is associated with increased reports of respiratory symptoms and reduced lung function, but the long-term effects of ETS are unclear, notably in healthy individuals with bronchial hyperresponsiveness (BHR). OBJECTIVE: To assess the longitudinal effects of ETS exposure on the development of respiratory symptoms and spirometry in subjects with BHR. METHODS: The study population included 1,661 never-smokers from the SAPALDIA (Swiss Study on Air Pollution and Lung Diseases in Adults) cohort, assessed in 1991 (baseline) and 11 yr later, who were symptom-free at baseline. Incident reports of respiratory symptoms and results of spirometry were assessed at the follow-up survey. MAIN RESULTS: Exposure to ETS reported in the two surveys was strongly associated with the development of cough (odds ratio, 2.1; 95% confidence interval, 1.2-3.7; p = 0.01). In subjects with BHR exposed to ETS at both surveys, a trend for strong associations were observed for wheeze, cough, dyspnea, and chronic bronchitis; however, the association reached statistical significance only for the symptom of dyspnea (p < 0.01). Lower FEV1/FVC (mean +/- SD, 72.9 +/- 7.7 vs. 76.8 +/- 6.1%; p < 0.01) and FEF(25-75) (forced expiratory flow, midexpiratory phase)/FVC (mean +/- SD, 56.1 +/- 22.5 vs. 68.1 +/- 21.6%; p < 0.01) were observed in subjects with BHR exposed to ETS compared with nonexposed subjects without BHR. Lower values were found in subjects continuing exposure by the follow-up survey. CONCLUSION: Exposure to ETS was strongly associated with the development of respiratory symptoms in previously asymptomatic subjects with BHR within 11 yr. Furthermore, subjects with underlying BHR had reduced lung function at follow-up, thus suggesting a higher risk for the development of chronic respiratory disease in this subset of the population.

Adult↗

PubMed2006

Stat1 and SUMO modification.

Many proteins are known to undergo small ubiquitin-related modifier (SUMO) modification by an E1-, E2-, and E3-dependent ligation process. Recognition that protein inhibitor of activated signal transducers and activators of transcription (STATs) (PIAS) proteins are SUMO E3 ligases raised the possibility that STATs may also be regulated by SUMO modification. Consistent with this possibility, a SUMO-ylation consensus site (PsiKxE; Psi indicates hydrophobic residue, and x indicates any residue) was identified in Stat1 (ie, (702)IKTE(705)), but not in other STATs. Biochemical analysis confirmed that Stat1 K(703) could be SUMO modified in vitro. Mutation of this critical lysine (ie, Stat1(K703R)) yielded a protein that, when expressed in Stat1(-/-) mouse embryonic fibroblasts (MEFs), exhibited enhanced DNA binding and nuclear retention. This was associated with modest changes in transcriptional and antiviral activity. However, mutation of the second critical residue in the SUMO consensus site, E(705) (ie, Stat1(E705A)), yielded a protein with wild-type DNA binding, nuclear retention, and transcriptional and antiviral activity. Similar observations were made when these mutants were expressed in primary Stat1(-/-) macrophages. These observations suggest that although Stat1 can uniquely be SUMO-ylated in vitro, this modification is unlikely to play an important role in regulating Stat1 activity in vivo.

Animals↗

PubMed2006

The absence of dyspnoea, cough and wheezing: a reason for undiagnosed airflow obstruction?

OBJECTIVES: The diagnosis of obstructive lung disease (OLD) may be overlooked because of the poor correlation between the intensity of symptoms and the severity of airway obstruction (AO). Undiagnosed airflow obstruction (UDAO) is associated with health impairment and mortality. Questions remain such as the reasons for its occurrence and the underlying diseases. In a pulmonologist's private practice, the objectives were to detect UDAO in the absence of dyspnoea, cough and wheezing, to improve its screening following other anamnestic data, and to separate UDAO patients into "silent asthma" (SA) or "persistent obstruction". METHODS: Patients were subjected to a verbal questionnaire for the detection of alternative indication for pulmonary function tests (PFTs), to a physical examination and, in the case of a severe smoking habit, to a chest X-ray. PFTs were performed whenever an OLD history or another lung disease was present and, in the absence of any dyspnoea, cough and wheezing, when other symptoms and conditions occurred (sputum, chest tightness, fatigue, rhinitis, snoring; active/passive smoking, recurrent lower respiratory tract infections, asthma in childhood or in family, atopy). RESULTS: Of 3762 consecutive patients, 1389 patients with AO were identified. Among them, 147 UDAO patients were detected with no history of dyspnoea, cough and wheezing (3.9% and 10.6%, respectively). All these patients had other suggestive symptoms and AO risk factors which justified PFTs. They presented with mild (65%), moderate (21%) or even severe (16%) AO. SA patients normalized their spirometric values under treatment. CONCLUSION: The absence of dyspnoea, cough and wheezing is a fairly frequent finding and a reason for UDAO. PFTs are warranted with any suggestive symptoms and AO risk factors. The favourable follow-up underlines the importance of screening for UDAO.

Adolescent↗

PubMed2006

Incidence, risk factors, and outcome of aspiration pneumonitis in ICU overdose patients.

OBJECTIVE: To assess the incidence and outcome of clinically significant aspiration pneumonitis in intensive care unit (ICU) overdose patients and to identify its predisposing factors. DESIGN: Retrospective cohort study. SETTING: Medical ICU of an academic tertiary care hospital. PATIENTS: A total of 273 consecutive overdose admissions. MEASUREMENTS AND RESULTS: Clinically significant aspiration pneumonitis was defined as the occurrence of respiratory dysfunction in a patient with a localised infiltrate on chest X-ray within 72 h of admission. In our cohort we identified 47 patients (17%) with aspiration pneumonitis. Importantly, aspiration pneumonitis was associated with a higher incidence of cardiac arrest (6.4 vs 0.9%; p = 0.037) and an increased duration of both ICU stay and overall hospital stay [respectively: median 1 (interquartile range 1-3) vs 1 (1-2), p = 0.025; and median 2 (1-7) vs 1 (1-3), p < 0.001]. In multivariate logistic regression analysis, Glasgow Coma Scale (GCS) score [odds ratio (OR) for each point of GCS 0.8; 95% confidence interval (CI) 0.7-0.9; p = 0.001], ingestion of opiates (OR 4.5; 95% CI 1.7-11.6; p = 0.002), and white blood cell count (WBC) (OR for each increase in WBC of 10(9)/l 1.05; 95% CI 1.0-1.19; p = 0.049) were identified as independent risk factors. CONCLUSIONS: Clinically relevant aspiration pneumonitis is a frequent complication in overdose patients admitted to the ICU. Moreover, aspiration pneumonitis is associated with a higher incidence of cardiac arrest and increased ICU and total in-hospital stay.

Adult↗

PubMed2006

Shoot growth of mature Fagus sylvatica and Picea abies in relation to ozone.

Epidemiological analysis of sequential growth data may be a tool in assessing ozone sensitivity of mature trees. Annual shoot growth of mature Fagus sylvatica in 83 Swiss permanent forest observation plots and of Picea abies in 61 plots was evaluated for 11 and 8 consecutive years, respectively, using branches harvested every 4 years. The data were assessed as annual deviation from average growth and related to fructification, ozone, meteorological parameters, and modelled soil water content using a mixed linear model. In beech, a significant association between ozone and shoot growth was observed which corresponded to a 7.4% growth reduction between 0 and 10 ppm h AOT40 (accumulated ozone over threshold 40). This is in the same order of magnitude as the response observed in experiments with seedlings. No interaction was found between ozone and drought parameters. In Norway spruce, shoot growth was neither associated with ozone nor with drought.

Disasters↗

PubMed2006

Teaching resources. Cytokine receptors and Jak-STAT signaling.

This Teaching Resource provides lecture notes and slides for a class covering interferons, their receptors, and Jak-STAT signaling and is part of the course "Cell Signaling Systems: A Course for Graduate Students." The lecture begins with a discussion of the different families of cytokines and their receptors and then proceeds to describe how cytokine receptor interactions lead to the activation of different members of the STAT family of transcription factors.

Amino Acid Motifs↗

PubMed2006

Cost-effectiveness of B-type natriuretic peptide testing in patients with acute dyspnea.

BACKGROUND: B-type natriuretic peptide (BNP) is a quantitative marker of heart failure that seems to be helpful in its diagnosis. METHODS: We performed a prospective randomized study (B-Type Natriuretic Peptide for Acute Shortness of Breath Evaluation) including 452 patients who presented to the emergency department with acute dyspnea to estimate the long-term cost-effectiveness of BNP guidance. Participants were randomly assigned to a diagnostic strategy involving the measurement of BNP levels (n = 225) or assessment in a standard manner (n = 227). Nonparametric bootstrapping was used to estimate the distribution of incremental costs and effects on the cost-effectiveness plane during 180 days of follow-up. RESULTS: Testing of BNP induced several important changes in management of dyspnea, including a reduction in the initial hospital admission rate, the use of intensive care, and total days in the hospital at 180 days (median, 10 days [interquartile range, 2-24 days] in the BNP group vs 14 days [interquartile range, 6-27 days] in the control group; P = .005). At 180 days, all-cause mortality was 20% in the BNP group and 23% in the control group (P = .42). Total treatment cost was significantly reduced in the BNP group (7930 dollars vs 10,503 dollars in the control group; P = .004). Analysis of incremental 180-day cost-effectiveness showed that BNP guidance resulted in lower mortality and lower cost in 80.6%, in higher mortality and lower cost in 19.3%, and in higher or lower mortality and higher cost in less than 0.1% each. Results were robust to changes in most variables but sensitive to changes in rehospitalization with BNP guidance. CONCLUSION: Testing of BNP is cost-effective in patients with acute dyspnea.

Acute Disease↗

PubMed2006

Outcome of radioiodine therapy without, on or 3 days off carbimazole: a prospective interventional three-group comparison.

PURPOSE: Carbimazole ameliorates hyperthyroidism but reduces radioiodine uptake and adversely affects the outcome of simultaneous radioiodine therapy. We explored whether withdrawal of carbimazole for 3 days can restore the outcome of radioiodine treatment without concurrent exacerbation of hyperthyroidism. By generating three groups with comparable radioiodine uptake, we also investigated whether the effect of carbimazole depends on the radioiodine uptake. METHODS: Stratified by a radioiodine uptake >30%, 227 consecutive adult patients were prospectively assigned to radioiodine therapy (target dose 200 Gy) without, on or 3 days off carbimazole. Patients were clinically (Crooks-Wayne score) and biochemically (T(3), fT(4), TSH) followed up after 3, 6 and 12 months. Primary endpoint was outcome 12 months after radioiodine therapy. RESULTS: A total of 207 patients completed follow-up (toxic nodular goitre, n=117; Graves' disease, n=90). The overall success rate was 71.5%. Patients without and 3 days off carbimazole had similar biochemical (81.4% and 83.3%, respectively; p=0.82) and clinical outcomes [median (range) Crooks-Wayne score 0 (0-16) and 1 (0-10), respectively; p=0.73], which were both higher than in patients on carbimazole [42.6%, p<0.001; Crooks-Wayne score 3 (0-30), p<0.03]. Time to achieve cure was delayed on carbimazole. No changes in thyroid hormone levels occurred after 3 days' discontinuation of carbimazole. Logistic regression revealed that all observed cure rates were independent of entity, sex, age, thyroid volume, radioiodine uptake, radioiodine half-life, fT(4), T(3) and TSH. CONCLUSION: Patients under carbimazole treatment can be referred for radioiodine therapy after withdrawal of carbimazole for only 3 days. Three days of carbimazole withdrawal is long enough to restore the success of radioiodine therapy and short enough to avoid the risk of exacerbation of hyperthyroidism.

Adult↗

PubMed2006

Feasibility of mobile cardiopulmonary exercise testing.

QUESTIONS UNDER STUDY: Evaluation of cardiopulmonary capacity and work ability is often done by cardiopulmonary exercise testing under laboratory conditions. Mobile CPET devices allow measurements under specific real-life conditions, i.e.: at the patient's workplace. We investigated the feasibility and validity of mobile CPET in healthy controls. METHOD: We compared oxygen uptake measured by mobile CPET (MCPET) with that by standard CPET (LCPET), and we compared oxygen uptake with markers of self-reported physical exhaustion. Twenty-two healthy subjects (15 male, 21-49 years) underwent LCPET and 6 outdoors 12-min running tests (MCPETs) at different intensities. Physical exhaustion and the time they could continue exercising (T(EX)) was reported for each level. Standard descriptive statistics were applied. RESULTS: Of 132 MCPETs, performed in 22 subjects, 128 (97%) were of suitable quality. The facemask was well tolerated and nobody felt uncomfortable at any time. On average VO2 [peak] was 21% (SD 9%) higher with MCPET compared to LCPET (median 3.60, range [2.22, 5.14] versus median 2.63, range [1.67, 4.16] L*min(-1)), but showed a strong correlation (r2 = 0.90). MCPET-VO2 at steady state correlated with subjectively rated physical exhaustion, and with TEX. CONCLUSIONS: Out-of-laboratory MCPET was feasible, correlated with parameters of standard CPET, and correlated with markers of physical exhaustion. After validation in patients, MCPET could be used for a rational evaluation of cardiopulmonary capacity and work ability in selected patients.

Adult↗

PubMed2006

Use of B-type natriuretic peptide in the management of acute dyspnea in patients with pulmonary disease.

BACKGROUND: In patients with pulmonary disease, it is often challenging to distinguish exacerbated pulmonary disease from congestive heart failure (CHF). The impact of B-type natriuretic peptide (BNP) measurements on the management of patients with pulmonary disease and acute dyspnea remains to be defined. METHODS: This study evaluated the subgroup of 226 patients with a history of pulmonary disease included in the BASEL Study. Patients were randomly assigned to a diagnostic strategy with (n = 119, BNP group) or without (n = 107, clinical group) the use of BNP levels provided by a rapid bedside assay. Time to discharge and total cost of treatment were recorded as the primary end points. RESULTS: Baseline characteristics were similar in patients assigned to the BNP and control groups. Comorbidity was extensive, including coronary artery disease and hypertension in half of patients. The primary discharge diagnosis was CHF and exacerbated obstructive pulmonary disease in 39% and 33%, respectively. The use of BNP levels significantly reduced the need for hospital admission (81% vs 91%, P = .034). Median time to discharge was 9.0 days in the BNP group as compared with 12.0 days (P = .001) in the clinical group. Median total cost of treatment was $4841 in the BNP group as compared with $5671 in the clinical group (P = .008). Inhospital mortality was 8% in both groups. CONCLUSIONS: CHF is a major cause of acute dyspnea in patients with a history of pulmonary disease. Used in conjunction with other clinical information, rapid measurement of BNP reduced time to discharge and total treatment cost of these patients.

Acute Disease↗

PubMed2006

Eleven-year single-center experience with the ATS Open Pivot Bileaflet heart valve.

BACKGROUND: The ATS Open Pivot Heart Valve was first introduced in 1992 and has been implanted routinely at our institution since 1993. Valve selection was based on surgeon preference. The objective of this study is to retrospectively analyze our 11-year clinical results with ATS prostheses. METHODS: Between January 1993 and December 2003, 601 ATS valves (393 aortic valve replacement [AVR], 168 mitral valve replacement [MVR], 20 aortic plus mitral valve replacement [DVR]) were implanted in 581 patients (377 male, 204 female; mean age, 63.7 years; range 18 to 89). Preoperatively, 47 (8%) were New York Heart Association class I, 212 (36.5%) were class II, 267 (46%) were class III, and 55 (9.5%) were class IV. Preoperative comorbidities were coronary artery disease, 167 (29%); diabetes mellitus, 72 (12%); cerebrovascular disease, 2 (0.3%); endocarditis, 53 (9%); and atrial fibrillation, 115 (20%). RESULTS: Follow-up is 99% complete. Data represent 2,500 cumulative patient-years. Mean follow-up is 4.3 +/- 2.6 years (range, 0.1 to 11.6). Overall hospital mortality is as follows: AVR, 3.8% (15 patients); MVR, 1.8% (3 patients); DVR, 10% (2 patients). Structural valve failure was not encountered. Overall survival at 10 years is AVR, 84.7% +/- 3.1%, AVR plus coronary artery bypass, 67.5% +/- 8.2%; MVR, 59.8% +/- 7.1%, MVR plus coronary artery bypass, 39% +/- 27.8%; and DVR, 74.3% +/- 10%. Freedom from valve-related death at 10 years is AVR, 99.2%; MVR, 94.6%; and DVR, 100%. Linearized rates for postoperative complications are paravalvular leak, 0.6% per patient-year; valve thrombosis, 0.04% per patient-year; thromboembolism, 1.1% per patient-year; major bleeding, 0.5% per patient-year; and de novo prosthesis endocarditis, 0.1% per patient-year. Postoperative mortality risk was significantly elevated by diabetes (p < 0.01), but not by other comorbidities. CONCLUSIONS: Our 11-year experience demonstrates low rates of adverse events and valve-related complications with the ATS Open Pivot heart valve.

Adolescent↗

PubMed2006

Heart rate variability in an ageing population and its association with lifestyle and cardiovascular risk factors: results of the SAPALDIA study.

AIMS: (i) To report associations between cardiovascular risk factors and heart rate variability (HRV) in a general population and (ii) to provide normal values for various HRV measurements in a healthy European general population sample aged >or=50. METHODS AND RESULTS: Twenty-four-hour electrocardiograms were recorded in 1742 randomly selected SAPALDIA (Swiss cohort study on Air Pollution and Lung Diseases in Adults) participants aged >or=50. In multivariate regression analyses, women (n=895) had a 6.1% lower standard deviation of all normal RR (NN) intervals (SDNN), a 11.4% lower total power (TP), and a 27.2% lower low-frequency (LF) power than men (n=847). Per unit increase in BMI, SDNN decreased by 0.7% and TP decreased by 1.2%. Persons with high blood pressure had a 9.2% lower LF than normotensive persons and current smokers a 15.5% lower LF than never smokers. Each hour of heavy physical exercise was associated with a 2.0% increase in SDNN, a 3.6% increase in the high frequency (HF) range power and a 4.2% increase in LF power. Higher levels of uric acid, high-sensitive C-reactive protein and non-HDL-cholesterol were associated with lower TP, HF and LF. Percentiles of TP and LF/HF as a function of age were calculated for an asymptomatic subsample of participants (n=499) free of cardioactive medications. CONCLUSION: Heart rate variability in a general population sample shows expected associations with all known cardiovascular risk factors, although not identically for all HRV domains. Together with our percentile estimates for HRV as a function of age, these findings could assist scientists in interpreting 24 h HRV values and factors influencing them in an ageing population.

Aging↗

PubMed2005

Reference values for methacholine reactivity (SAPALDIA study).

BACKGROUND: The distribution of airway responsiveness in a general population of non-smokers without respiratory symptoms has not been established, limiting its use in clinical and epidemiological practice. We derived reference equations depending on individual characteristics (i.e., sex, age, baseline lung function) for relevant percentiles of the methacholine two-point dose-response slope. METHODS: In a reference sample of 1567 adults of the SAPALDIA cross-sectional survey (1991), defined by excluding subjects with respiratory conditions, responsiveness during methacholine challenge was quantified by calculating the two-point dose-response slope (O'Connor). Weighted L1-regression was used to estimate reference equations for the 95th , 90th , 75th and 50th percentiles of the two-point slope. RESULTS: Reference equations for the 95th , 90th , 75th and 50th percentiles of the two-point slope were estimated using a model of the form a + b* Age + c* FEV1 + d* (FEV1)2 , where FEV1 corresponds to the pre-test (or baseline) level of FEV1. For the central half of the FEV1 distribution, we used a quadratic model to describe the dependence of methacholine slope on baseline FEV1. For the first and last quartiles of FEV1, a linear relation with FEV1 was assumed (i.e., d was set to 0). Sex was not a predictor term in this model. A negative linear association with slope was found for age. We provide an Excel file allowing calculation of the percentile of methacholine slope of a subject after introducing age--pre-test FEV1--and results of methacholine challenge of the subject. CONCLUSION: The present study provides equations for four relevant percentiles of methacholine two-point slope depending on age and baseline FEV1 as basic predictors in an adult reference population of non-obstructive and non-atopic persons. These equations may help clinicians and epidemiologists to better characterize individual or population airway responsiveness.

Age Distribution↗

PubMed2005

Longitudinal validity of spirometers--a challenge in longitudinal studies.

QUESTION UNDER STUDY: Pulmonary function testing (PFT) in longitudinal studies involves the repeated use of spirometers over long time periods. We assess the comparability of PFT results taken under biologic field conditions using thirteen certified devices of various technology and age. Comparability of measurements across devices and over time is relevant both in clinical and epidemiological research. METHODS: Forced Vital Capacity (FVC), Forced Expiratory Volume in the first second (FEV1) and Forced Expiratory Flow 50% (FEF50) were compared before and after the data collection of the Swiss Study on Air Pollution and Lung Diseases in Adults (SAPALDIA) and the European Community Respiratory Health Survey (ECRHS) cohort studies. Three test series were conducted with 46, 50 and 56 volunteers using various combinations of spirometers to compare the eight flow-sensing spirometers (Sensormedics 2200) used in the SAPALDIA cross-sectional and follow-up, two new flow-sensing instruments (Sensormedics Vmax) and three volume displacement spirometers (two Biomedin/Baires and one Sensormedics 2400). RESULTS: The initial comparison (1999/2000) of eight Sensormedics 2200 and the follow-up comparison (2003) of the same devices revealed a maximal variation of up to 2.6% for FVC, 2.4% for FEV1 and 2.8% for FEF50 across devices with no indication of systematic differences between spirometers. Results were also reproducible between Biomedin, Sensormedics 2200 and 2400. The new generation of Sensormedics (Vmax) gave systematically lower results. CONCLUSIONS: The study demonstrates the need to conduct spirometer comparison tests with humans. For follow-up studies we strongly recommend the use of the same spirometers.

Adolescent↗

PubMed2005

Liveborn and stillborn very low birthweight infants in Switzerland: comparison between hospital based birth registers and the national birth register.

BACKGROUND AND AIM: Perinatal and infant mortality rates are considered key indicators of medical care. The aim of this investigation was to examine how representative and reliable the official national figures of Switzerland are by comparing them with the data in local birth registers. METHODS: 124 of 156 maternity hospitals in Switzerland, catering for about 80% of all newborn infants, participated in the study. The hospital based birth registers were screened for the years 1996 and 2000 for live and stillborn infants weighing less than 1500 g. These data were matched with the data in the official register (federal office for statistics). RESULTS: in 1996 a total of 753 newborn infants and in 2000 820 infants weighing between 300 and 1499 g were officially registered. In the hospital based registers in 1996 101 additional infants and in 2000 94 infants were identified that had not been officially registered; 31 of these were stillborn before 24 completed weeks. Infants registered only locally had lower birth weight and lower gestational age than those recorded in both registers. CONCLUSION: In Switzerland a significant number of very low birth weight infants who died soon after birth are not officially registered. If these infants are included, the national perinatal mortality rate would increase from 6.9 per thousand to 8.0 per thousand. Reasons for underreporting are unclear but may be due to varying definitions of stillbirth and different lower limits for reporting in various cantons. We suggest adopting the WHO-rules for reporting all births and to include gestational age, head circumference, Apgar scores and umbilical artery pH in the national birth register.

Female↗