Utilidad del índice FEV1/FEV6 en pacientes pluripatológicos hospitalizados para detectar la prevalencia de obstrucción pulmonar / Usefulness of the FEV1/FEV6 ratio to detect the prevalence of lung obstruction in hospitalised patients with multiple morbidities

Introducción. La prevalencia de obstrucción pulmonar aumenta con la edad y la presencia de comorbilidades. Aunque para confirmar su diagnóstico es necesario completar una espirometría, esta puede ser difícil de realizar en ancianos con deterioro cognitivo o dependencia funcional. Recientemente el uso de dispositivos portátiles que utilizan el índice FEV1/FEV6 han demostrado su utilidad para evaluar la presencia de obstrucción pulmonar, con una mayor facilidad de uso, aunque su utilidad en población anciana con pluripatología no ha sido establecida. Metodología. Estudio transversal, realizado en pacientes ingresados en la Unidad de pacientes crónicos complejos del Hospital Universitario Mútua de Terrassa. A todos ellos se les realizó un cuestionario que incluía -entre otras- medidas de dependencia funcional y deterioro cognitivo y se intentaron completar previamente al alta 3 maniobras válidas de FEV1/FEV6 con el aparato Piko-6, considerándose criterio de obstrucción un FEV1/FEV6≤0,75. Se analizaron las características de la población que fue capaz de realizar las pruebas, y la prevalencia de obstrucción pulmonar. Resultados. Se estudiaron 54 pacientes, de los cuales 35 (64,81%) realizaron las maniobras correctamente. Los pacientes que no completaron las maniobras tenían más dependencia funcional (Barthel 19 vs. 72, p<0,0001) y más deterioro cognitivo (Pfeiffer 1 vs. 9, p<0,0001; MEC 3/35 vs. 28/35, p<0,010). La prevalencia de obstrucción fue del 71,43%, con un 72% de infradiagnóstico. Conclusiones. En un 35,18% de los pacientes no se consiguió determinar el FEV1/FEV6, por deterioro cognitivo o dependencia funcional. Tanto la prevalencia de obstrucción como el infradiagnóstico superaron el 70% (AU)

Background. The prevalence of lung obstruction increases with age and the presence of comorbidities. Although a complete spirometry is necessary to confirm the diagnosis, this may be impractical in elderly patients with cognitive impairment or functional dependence. Recently, the use of portable devices using the FEV1/FEV6 ratio have shown to be useful for assessing the presence of lung obstruction, with greater ease of use, but its usefulness has not been established in the elderly population with multiple morbidities. Methods. A cross-sectional study was conducted on patients hospitalised in the complex chronic patients Unit of the University Hospital Mútua de Terrassa. All of them completed a questionnaire that included -among other things- measurements of functional dependence and cognitive impairment. Three manoeuvres validated with the Piko-6 device were attempted before discharge, and considering an FEV1/FEV6<0.75 as criteria for obstruction. An analysis was performed on the characteristics of the population that was able to perform the tests, as well as the prevalence of pulmonary obstruction. Results. A total of 54 patients were included in the study, of which 35 (64.81%) performed the manoeuvres correctly. Patients who were unable to complete the manoeuvres of the Piko-6 had more functional dependence (Barthel 19 vs. 72, P<.0001) and cognitive impairment (Pfeiffer 1 vs. 9, P<.0001; MEC 28/35 vs. 3/35, P<.010). The prevalence of obstruction was 71.43%, with an underdiagnosis of 72%. Conclusions. The FEV1/FEV6 ratio was not determined in 35.18% of the patients due to cognitive impairment or functional dependence. The prevalence of obstruction and underdiagnosis exceeded 70% (AU)

Cigarette smoking, cadmium exposure, and zinc intake on obstructive lung disorder.

BACKGROUND AND OBJECTIVE: This study examined whether zinc intake was associated with lower risk of smoking-induced obstructive lung disorder through interplay with cadmium, one of major toxicants in cigarette smoke. METHODS: Data were obtained from a sample of 6,726 subjects aged 40+ from the Third National Health and Nutrition Examination Survey. The forced expiratory volume in 1 second (FEV1) and forced vital capacity (FVC) were measured using spirometry. Gender-, ethnicity-, and age-specific equations were used to calculate the lower limit of normal (LLN) to define obstructive lung disorder as: observed FEV1/FVC ratio and FEV1 below respective LLN. Zinc intake was assessed by questionnaire. Logistic regression analysis was applied to investigate the associations of interest. RESULTS: The analyses showed that an increased prevalence of obstructive lung disorder was observed among individuals with low zinc intake regardless of smoking status. The adjusted odds of lung disorder are approximately 1.9 times greater for subjects in the lowest zinc-intake tertile than those in the highest tertile (odds ratio = 1.89, 95% confidence interval = 1.22-2.93). The effect of smoking on lung function decreased considerably after adjusting for urinary cadmium. Protective association between the zinc-to-cadmium ratio (log-transformed) and respiratory risk suggests that zinc may play a role in smoking-associated lung disorder by modifying the influence of cadmium. CONCLUSIONS: While zinc intake is associated with lower risk of obstructive lung disorder, the role of smoking cession and/or prevention are likely to be more important given their far greater effect on respiratory risk. Future research is warranted to explore the mechanisms by which zinc could modify smoking-associated lung disease.

[Long-term domiciliary oxygen therapy (LTOT) in Poland in the years 1986-2005]. / Domowe leczenie tlenem (DLT) w Polsce w latach 1986-2005.

INTRODUCTION: Long-term domiciliary oxygen therapy (LTOT) is part to of pulmonary care system. Uniform qualification criteria and methods of follow-up for patients undergoing LTOT have been adopted. There are 63 LTOT centres located in Poland run by specialists in pulmonology. On the occasion of 20 years of LTOT in Poland, an analysis of its development, number of patients treated, diagnoses, survival and equipment was performed. MATERIAL AND METHODS: Data were taken from structurized LTOT centres reports. RESULTS AND CONCLUSIONS: A history of LTOT may be divided into 3 periods, steady grow in the years 1986-1991, stagnation between 1992-2000 and rapid grow in the last 3 years. On 01.01.2006 there was 2601 patients receiving LTOT therapy. The most common diagnosis was COPD (85%) followed by kyphoscolisis (5%), TB sequels (4.6%), IPF (3.6%) and other rare diseases. Treatment is reimbursed by the National Health System. Oxygen is administered via an oxygen concentrator. Due to insufficient resources from the NHS the needs for LTOT treatment are not fulfilled. There are 8.4 patients treated with LTOT per 100 000 people, with large regional differences ranging from 3.7 to 14.9/100 000. The most frequent cause of death in patients receiving LTOT treatment was exacerbation of respiratory failure (71.3%), followed by sudden death (5.1%), myocardial infarction or pulmonary embolism (4.4%), lung cancer (4%) and other or not known causes (15.2%). Survival in patients receiving LTOT treatment from the years 1986-1995 was rather short: 54.6% survived less than 3 years, 3-4 years survived 13.3%, 4-5 years 11.3% and more than 5 years survived 19.7% of treated patients.

Respiratory findings in pharmaceutical workers.

BACKGROUND: Pharmaceutical workers may be at risk for the development of respiratory problems as a result of their work environment. METHODS: This study investigated 163 female and 35 male workers, employed in a pharmaceutical plant processing different types of medication, primarily antibiotics, in order to characterize the risk of this environment. Chronic respiratory symptoms were recorded by using the British Medical Research Council questionnaire. Acute symptoms, which developed during the work shift, were also recorded. Ventilatory capacity was measured by recording maximum expiratory flow-volume (MEFV) curves on which FVC, FEV1, FEF50, and FEF25 were measured. Controls (113) were selected from a food packing facility. RESULTS: A significantly higher prevalence of chronic respiratory symptoms was recorded among workers (compared to controls), the highest being for sinusitis, nasal catarrh, and dyspnea. There was also a high prevalence of acute symptoms recorded during the workshift. Odds ratio showed that the most significant risk factors for these respiratory findings were smoking and length of time worked in the pharmaceutical industry, particularly in men. Pulmonary function testing demonstrated significantly decreased measured values in comparison to predicted European pulmonary function measurements (P < 0.01). This was particularly pronounced for FEF50 and FEF25, suggesting obstructive changes in smaller airways. CONCLUSIONS: Our data suggest that workers employed in the pharmaceutical industry may develop respiratory symptoms accompanied by ventilatory impairment.

Chronic obstructive pulmonary disease and intake of catechins, flavonols, and flavones: the MORGEN Study.

Flavonoids have been suggested to protect against chronic lung disease. We studied intake of catechins, flavonols, and flavones in relation to pulmonary function and COPD symptoms in 13,651 adults from three Dutch cities examined from 1994 to 1997. Dietary intake was estimated using a food frequency questionnaire, and flavonoid intake was calculated using specific food composition tables. Pulmonary function (FEV1) was determined by spirometry and COPD symptoms by questionnaire. Associations were presented for the fifth versus the first quintile of intake (Q5-Q1), adjusted for age, height (for FEV1 only), sex, smoking, BMI, and energy intake. Smoking was strongly associated with COPD, independent of dietary effects. Average catechin, flavonol, and flavone intake was 58 mg/d (SD = 46) with tea and apples as main sources. Total catechin, flavonol, and flavone intake was positively associated with FEV1 (beta(Q5-Q1) = 44 ml, 95% CI = 18-69) and inversely associated with chronic cough (OR(Q5-Q1) = 0.80, 95% CI = 0.66-0.97) and breathlessness (OR(Q5-Q1) = 0.74, 95% CI = 0.58- 0.94), but not chronic phlegm. Catechin intake was independently associated with FEV1 (beta(Q5-Q1) = 130 ml, 95% CI = 101-159) and all three COPD symptoms (OR(Q5-Q1) = 0.60-0.72, p < 0.001). Flavonol and flavone intake was independently associated with chronic cough only. Solid fruit, but not tea, intake was beneficially associated with COPD. Our results suggest a beneficial effect of a high intake of catechins and solid fruits against COPD.

Dietary influences on chronic obstructive lung disease and asthma: a review of the epidemiological evidence.

The epidemiological evidence for a relationship between diet and indicators of asthma and chronic obstructive pulmonary disease (COPD) is evaluated. The review focuses on the intake of Na, n-3 fatty acids, and antioxidant vitamins as well as fruit and vegetables. Experimental studies suggest that a high-Na diet has a small adverse effect on airway reactivity in asthma patients. However, observational studies provide no clear evidence that high Na intake has adverse effects on airway reactivity or asthma symptoms in open populations. n-3 Polyunsaturated fatty acids, which are present in fish oils, are metabolized into less broncho-constricting and inflammatory mediators than n-6 polyunsaturated fatty acids. Studies in the general adult population suggest that a high fish intake has a beneficial effect on lung function, but the relationship with respiratory symptoms and clinically-manifest asthma or COPD is less evident. Also, experimental studies in asthma patients have not demonstrated an improvement in asthma severity after supplementations with fish oil. Several studies showed a beneficial association between fruit and vegetable intake and lung function, but the relationship with respiratory symptoms and the clinically-manifest disease was less convincing. A similar pattern was found for vitamin C in relation to indicators of asthma and COPD, but there are still conflicting results with respect to vitamin E and beta-carotene. In conclusion, the epidemiological evidence for a beneficial effect on indicators of asthma and COPD of eating fish, fruit and vegetables is increasing. However, the effectiveness of dietary supplementation in open-population samples is often not demonstrated. Several unresolved questions are raised, which should be addressed in future studies on the relationship between diet and respiratory disease.

Prevalence of co-morbidity in lung cancer patients and its relationship with treatment: a population-based study.

BACKGROUND: With the rising mean age of lung cancer patients, the number of patients with serious co-morbidity at diagnosis is increasing. As a result, co-morbidity may become an important factor in both the choice of treatment and survival. We studied the prevalence of serious co-morbidity among newly diagnosed lung cancer patients and its association with morphology, stage and treatment. PATIENTS: A total of 3864 lung cancer patients registered in the population-based registry of the Comprehensive Cancer Centre South between 1993 and 1995. RESULTS: During the study period, the mean age of patients was 67 years (range: 29-93). The most frequent concomitant diseases were cardiovascular diseases (23%), chronic obstructive pulmonary diseases (COPD) (22%) and other malignancies (15%). The prevalence of concomitant diseases was highest for men (60%), patients with squamous-cell carcinoma (64%) and those with a localised tumour (66%). The resection rate for patients < 70 years, with a localised non-small-cell lung tumour, was especially low for those with COPD (67%) or diabetes (64%) compared with patients without concomitant diseases (94%). The association between co-morbidity and chemotherapy for patients with small-cell lung cancer was limited. CONCLUSIONS: The prevalence of co-morbidity, especially cardiovascular diseases and COPD, among lung cancer patients is about twice as high as in the general population. Co-morbidity seems to be associated with earlier diagnosis of lung cancer, but it may also lead to less accurate staging and less aggressive treatment. Thus, prognosis is likely to be negatively influenced by co-morbidity.

Late onset asthma clinical and immunological data: importance of allergy.

In people over 65 years of age (mean age 72) late onset asthma (LOA) is often mistaken for chronic obstructive pulmonary disease (COPD). Furthermore, it is generally believed that true allergic asthma starts very seldom in old age and that, in this case, it is actually intrinsic asthma i.e., without any sensitization to aeroallergens. The aim of this study was to show that LOA is not an uncommon entity and is often allergic. Among a population of 1,888 subjects (over 65 years of age) in a general medicine ward we found 21 patients (1.1%) corresponding to this entity. The diagnosis of asthma was assessed according to clinical data, pulmonary function and nasal provocation tests, and blood eosinophilia. The diagnosis of atopy was assessed on total IgE, prick tests and RAST for the commonest allergens of our area. This group of 21 patients was compared to three groups of age-matched subjects including: 68 patients afflicted with chronic bronchitis, a group of 14 patients who had asthma before the age of 65 (presenile asthma), and 20 normal controls. A group of 15 asthmatics under age 65 was also included (young asthma mean age 37). We found a rather high incidence of allergy (72%), mostly to Dermatophagoides pteronyssinus, but also to the pollens Parietaria judaica, grasses and Olea europea. Although the average age (except in the young asthma group) and the severity of symptoms were the same in the four groups, unexpectedly mean RAST and skin test values were higher in LOA than in the two groups of young asthmatics and presenile asthmatics. It was concluded that LOA is not uncommon among elderly patients over 65, which is in contrast with most previous studies; 72% of our cases were allergic, the main allergens being mite, and Parietaria judaica pollen.

Serum house-dust-mite antibodies and reduced FEV1 in adults of a Norwegian community.

In this cross-sectional study we investigated whether the presence of specific serum IgE antibodies to house dust mite, timothy, birch, cat, and mold was associated with a reduced FEV1 in adults. We performed complete examinations on 82% of a stratified random sample of 18 to 73-yr-old adults (n = 1,239). Subjects with house-dust-mite antibodies had lower (p = 0.002) sex, age, and height standardized residuals of FEV1 (SFEV1) than those without any specific IgE antibody. This relationship did not differ significantly by sex, age, smoking habit, total serum IgE level, or season, and remained significant after excluding subjects with obstructive lung disease. For house-dust-mite antibodies we also observed a dose-response relationship between antibody levels and impaired lung function. In a final multiple linear regression analysis the presence of house-dust-mite antibodies was the only significant predictor (regression coefficient: -0.425; SE = 0.189; p = 0.02) of reduced SFEV1 after adjusting for smoking habit and lifetime tobacco consumption, season, total serum IgE level, and respiratory-symptom and disease status. Thus, house-dust-mite allergy is an independent predictor of reduced lung function in adults of a wide age range.

[Chronic obstructive bronchopneumopathy. Epidemiologic aspects and balneotherapy potential]. / Broncopneumopatie croniche ostruttive (BPCO). Aspetti epidemiologici e possibilità crenoterapiche.

The authors remember the epidemiological data of BPCO in Italy and in the world and stress the increasing incidence and prevalence of these disease, interesting above all industrial-urban areas, middle and old aged, males and smokers. The pathogenetic role of atmospheric pollution, caused by industries, heating system and motor vehicles, in exposed. At the end Auctors summarise the results of the inhalatory therapy by mineral waters in BPCO, especially of sulphureas and salso-jodic spas.

Home treatment for chronic respiratory insufficiency: the situation in Europe in 1992. The European Working Group on Home Treatment for Chronic Respiratory Insufficiency.

The search for improved quality of life and a reduction in health care costs is leading to the development of home treatment. The organization of home treatment for chronic respiratory patients in 13 European countries was evaluated at the end of 1992 by means of a questionnaire. Switzerland and the Association Nationale pour le Traitement A Domicile de l'Insuffisance Respiratoire Chronique (ANTADIR) in France maintain registers for patients on oxygen therapy, mechanical ventilation and sleep disorders. Sweden and Poland have a national register for patients receiving oxygen. In other countries, some information can be obtained from the National Health Service or the commercial provider. Oxygen concentrators are used preferentially in all countries except Italy, Denmark, Spain and The Netherlands. Home ventilator treatment is generally performed by volume-cycled ventilators. National prescription rules exist in some parts of Spain, Switzerland and Belgium. In other countries, such as Germany, prescriptions rely on recommendations elaborated by specialists or international guidelines. Service and equipment are provided by national organizations, health services, commercial companies or hospitals. Home supervision of the patient is performed by a nurse and/or a doctor and equipment maintenance by a technician. Important differences exist between countries in Europe in home treatment of chronic respiratory disease. Comparative analysis should help achieve uniform standards and provide a basis for future research.

Ventilatory load characteristics during ventilatory muscle training.

The response of skeletal muscle to training is influenced by both the intensity and nature of the training stimulus. In this study we investigated the characteristics of the ventilatory load applied to the ventilatory muscles during several different modes of ventilatory muscle training. Patients with chronic obstructive pulmonary disease (COPD) performed the following breathing maneuvers: (1) Unloaded hyperpnea (UH), (2) resistive breathing through a fixed orifice (0.5 cm diameter) at frequencies of 15 and 30 breaths/min (RT15, RT30), (3) loaded breathing through a threshold valve set at 30% of the PImax at frequencies of 15 and 30 breaths/min (TT15, TT30), and (4) repetitive maximal inspiratory maneuvers against a closed shutter (PImax). During these maneuvers were recorded airflow and pressures at the month and esophagus, and from these measurements we derived VE and the work of breathing (WOB), tension time index (TTI), and pressure time product (PTP). The VE during UH was significantly higher than all other modes (p < 0.01), whereas the Pesmax was significantly lower during UH than during the resistive and loaded maneuvers (p < 0.01). The WOB did not differ during UH, TT30, and RT30, but was significantly higher in all three modes than at TT15 and RT15 (p < 0.05). During RT30 the TTI was higher than during TT30, TT15, and RT15 (p < 0.05), whereas the TTI during UH was significantly lower than during other maneuvers (p < 0.01). As expected, the highest Pesmax and PTP were found during the PImax maneuver. These data show that important qualitative differences in ventilatory muscle loading can be achieved by means of different devices and breathing strategies.(ABSTRACT TRUNCATED AT 250 WORDS)

Muscular metabolism during oxygen supplementation in patients with chronic hypoxemia.

The effects of supplemental oxygen (O2) versus air on working calf muscle metabolism were studied in seven patients with stable chronic obstructive pulmonary disease (COPD) and chronic hypoxemia (PaO2 = 57 +/- 3 SE mm Hg) and seven age-matched control subjects. Oxygen and air were randomly administrated at 24-h intervals, and O2 flow rate was adjusted to correct hypoxemia (PaO2 = 87 +/- 4 mm Hg) in the COPD group. The relative concentrations of ATP, phosphocreatine (PCr), inorganic phosphate (Pi), phosphomonoesters (PME), and the intracellular pH (pHi) were determined with 31P magnetic resonance spectroscopy at rest, during a graded standardized and localized exercise protocol (360 active plantar flexions), and during recovery. In resting muscle no significant effect of added O2 was demonstrable in each group with regard to pHi, Pi/PCr, and ATP/(PCr+Pi+PME) ratios. Mechanical data were similar between the two groups and between the two tests during the whole exercise. The indices of muscular oxidative metabolism (Pi/PCr and pHi at the end of exercise and recovering PCr resynthesis rate) were impaired in the COPD group compared with that in the control group during air (all p < 0.05). All these parameters were significantly improved with added O2 in the COPD group (p < 0.05), whereas no similar effects were observed in the control group. However, these beneficial effects were incomplete since the exercising Pi/PCr ratio remained higher in the COPD group than in the control group during added O2. This energetic muscular impairment could correspond to tissular damage related to chronic hypoxemia.

Relación entre cambios espirométricos y gases en sangre arterial en pacientes con enfermedad pulmonar obstructiva crónica descompensada / Relation between changes of spirometry and arterial blood gases in patients with COPD (Chronic Obstructive Pulmonary Disease)

No se conoce claramente si existe alguna asociación entre el grado de mejoría espirométrica y los gases en sangre arterial luego de la recuperación de la descompensación de pacientes con EPOC. Por tal motivo estudiamos retrospectivamente los cambios de gases en sangre y espirométricos al ingreso y al alta luego de la recuperación de la descomposición en cuarenta episodios ocurridos en treinta pacientes con EPOC. Se realizaron determinaciones de FEVI, FVC, Pa02, PaC02, AaD02 y pH al ingreso y al alta. Excepto el AaD02, todos estos valores mejoraron significativamente al alta. No se encontraron correlaciones significativas entre el FEVI o FVC versus Pa02, pH o AaD02 tanto al ingreso como al egreso. Se encontraron correlaciones débiles entre la PaC02 de ingreso o egreso versus el FEVI de ingreso o egreso. No se encontraron correlaciones significativas entre los cambios de FEVI o FVC antes y después de la descompensación versus los cambios ocurridos en la Pa02 o PaC02. Sólo los cambios de la Pa02 y del AaD02 se asociaron débilmente a los cambios del FVC. Se encontraron correlaciones significativas entre la Pa02 de ingreso versus los cambios de la Pa02 al alta e ingreso y entre la PaC02 de ingreso versus los cambios de la PaC02. No se encontraron correlaciones entre el tiempo de internación y los cambios espirométricos o de gases en sangre. Tampoco se obtuvieron correlaciones significativas entre el TLC en porcentaje del teórico versus los cambios espirométricos o de gases en sangre. La débil correlación hallada entre la mejoría de la Pa02 y el cambio del FVC y la falta de correlación entre el cambio de la PaC02 versus los cambios del FEVI o del FVC sugieren que la mejoría de los gases en sangre luego de la descompensación dependería principalmente de otros mecanismos no mensurables directamente con el FEVI o el FVC

Relación entre cambios espirométricos y gases en sangre arterial en pacientes con enfermedad pulmonar obstructiva crónica descompensada / Relation between changes of spirometry and arterial blood gases in patients with COPD (Chronic Obstructive Pulmonary Disease)

No se conoce claramente si existe alguna asociación entre el grado de mejoría espirométrica y los gases en sangre arterial luego de la recuperación de la descompensación de pacientes con EPOC. Por tal motivo estudiamos retrospectivamente los cambios de gases en sangre y espirométricos al ingreso y al alta luego de la recuperación de la descomposición en cuarenta episodios ocurridos en treinta pacientes con EPOC. Se realizaron determinaciones de FEVI, FVC, Pa02, PaC02, AaD02 y pH al ingreso y al alta. Excepto el AaD02, todos estos valores mejoraron significativamente al alta. No se encontraron correlaciones significativas entre el FEVI o FVC versus Pa02, pH o AaD02 tanto al ingreso como al egreso. Se encontraron correlaciones débiles entre la PaC02 de ingreso o egreso versus el FEVI de ingreso o egreso. No se encontraron correlaciones significativas entre los cambios de FEVI o FVC antes y después de la descompensación versus los cambios ocurridos en la Pa02 o PaC02. Sólo los cambios de la Pa02 y del AaD02 se asociaron débilmente a los cambios del FVC. Se encontraron correlaciones significativas entre la Pa02 de ingreso versus los cambios de la Pa02 al alta e ingreso y entre la PaC02 de ingreso versus los cambios de la PaC02. No se encontraron correlaciones entre el tiempo de internación y los cambios espirométricos o de gases en sangre. Tampoco se obtuvieron correlaciones significativas entre el TLC en porcentaje del teórico versus los cambios espirométricos o de gases en sangre. La débil correlación hallada entre la mejoría de la Pa02 y el cambio del FVC y la falta de correlación entre el cambio de la PaC02 versus los cambios del FEVI o del FVC sugieren que la mejoría de los gases en sangre luego de la descompensación dependería principalmente de otros mecanismos no mensurables directamente con el FEVI o el FVC (AU)

Multivariate analysis of ambient environmental factors and respiratory effects.

Relationships between respiratory health and environmental conditions (pollen, pollution and meteorology) are investigated in 204 subjects in four symptom groups in four geographical clusters in Tucson. Techniques used are principal components, factor and path analysis. Daily respiratory symptoms and peak expiratory flows were recorded during a three-year period. Ambient pollutants, meteorological conditions and pollen types were monitored in or near the clusters. Factor-based scales, which are climate and season specific, are developed for the environmental variables. Three pollutant/meteorological scales represent 'Summer', 'Winter', and 'Humidity'. Four pollen scales represent early and late spring, summer and fall pollen types. Relationships between environmental variables, respiratory symptoms and peak expiratory flow are analyzed with path diagrams, after accounting for age, sex, smoking habits and stove type. The different effects of the environment on asthmatics, allergics and airways obstructive disease subjects have been demonstrated. Many relationships were found between environmental factors and respiratory responses. The pollutant and meteorological variables are related to respiratory symptoms and peak flow directly as well as through interactions with pollen types. Some of the largest positive coefficients are seen in association with seasonal pollen types, specifically, rhinitis and dyspnoea.

Ten years of epidemiologic investigations on man-made mineral fibers and health.

This paper introduces the reports that follow it in a supplement dealing with the extended follow-up of mortality and cancer incidence among workers in the man-made mineral fiber (MMMF) production industry in Europe, the largest international study of its kind thus far initiated. In addition it reviews the prior epidemiologic evidence on this subject, both in terms of the earlier results of the same study and the results of other studies on the long-term effects of occupational exposure to MMMF. The conclusion drawn from this prior evidence was that the possibility that some excess of lung cancer may be causally related to exposure to MMMF could not be ruled out of the range of reasonable interpretations. When the findings of the extended follow-up, which this paper introduces, are added to the existing evidence, the overall results were considered to endorse the indication that no adverse long-term health effects have been detectable in terms of mortality throughout almost all segments of the MMMF production industry and to support the inference that MMMF--as present in the environmental conditions of early slag-wool/rock-wool production--may have played a role in the causation of lung cancer.