Activity-related breathlessness is twice as common among females as males in the general population and is associated with adverse health outcomes. We tested whether this sex difference is explained by the lower absolute forced expiratory volume in 1 s (FEV 1 ) or forced vital capacity (FVC) in females. This was a cross-sectional analysis of 3250 subjects (51% female) aged 38−67 years across 13 countries in the population-based third European Community Respiratory Health Survey. Activity-related breathlessness was measured using the modified Medical Research Council (mMRC) scale. Associations with mMRC were analysed using ordered logistic regression clustering on centre, adjusting for post-bronchodilator spirometry, body mass index, pack-years smoking, cardiopulmonary diseases, depression and level of exercise. Activity-related breathlessness (mMRC ≥1) was twice as common in females (27%) as in males (14%) (odds ratio (OR) 2.21, 95% CI 1.79−2.72). The sex difference was not reduced when controlling for FEV 1 % predicted (OR 2.33), but disappeared when controlling for absolute FEV 1 (OR 0.89, 95% CI 0.69−1.14). Absolute FEV 1 explained 98−100% of the sex difference adjusting for confounders. The effect was similar within males and females, when using FVC instead of FEV 1 and in healthy never-smokers. The markedly more severe activity-related breathlessness among females in the general population is explained by their smaller spirometric lung volumes.
A range for the airway resistance (R), reference resistance (Rref), quotient (R/Rref) measured by whole body plethysmography is given for unspecific inhalative provocation in asthmatic patients. 1. In patients with an initial R/Rref value less than 2 (R about 0,6 kPa/l/s) the non allergic reaction did not exceed an R/Rref quotient of 2,7. 2. Those patients with an initial R/Rref quotient greater than 2 but less than 5 reached an R/Rref value of 8.5 after non allergic provocation, which equals an R of about 1,75 kPa/l/s. It is recommended to provoke only those patients in whom the initial R/Rref quotient is in the beginning smaller than 2; because it is otherwise difficult to separate allergic from non allergic reactions and the necessary allergen induced bronchospasm might be harmful. Reference values for specific airway resistance have the advantage that we do not need a panting manouvre against a closed shutter which is often difficult to achieve especially with children during an asthmatic attack.
Five patients were studied using a randomly assigned sequence of four inspired-air conditions during strenuous treadmill exercise for 10 min. The four inspired-air conditions were: (1) Cool, dry room air (CDA) at 23 degrees C with 3 mg of water and 7.3 cal of heat content/l, (2) over-saturated air (OSA) at room temperature containing 43 mg water and 16.3 cal/l, (3) hot, dry air (HDA) at 120 degrees C having 3 mg water and 24.4 cal/l, and (4) warm, humidified air (WHA) at 37 degrees C with 43 mg water and 34.7 cal/l. Using inspired-air CDA and OSA, all patients manifested exercise-induced asthma (EIA) while forced expiratory volume in 1 sec (FEV1) and maximal mid-expiratory flow (MMEF) decreased to an average of 81% and 63% of the baseline when breathing CDA and to 83% and 71% of the baseline when breathing OSA. With WHA, EIA was clearly prevented while the post-exercise FEV1 and MMEF were 101% and 103% of baseline, respectively. With HDA, the post-exercise FEV1 and MMEF were 95% and 86% of baseline, respectively. Analysis of variance revealed that the post-exercise pulmonary function changes had resulted solely from respiratory heat loss and not from water loss or from interaction of heat and water losses. These results indicate that exercise-induced asthma is associated with airway cooling incurred during exercise rather than airway dehydration.
A method is described for correlative radiological and pathological studies of the lung post mortem, including radiography after air inflation, fixation with formalin-polyethylene glycol-alcohol solution, air drying and systematic histological sampling of lung tissue. For morphometric studies the total lung capacity during life is determined from radiograms and compared with the volume of the excised lung after fixation. The method is simple, relatively inexpensive, and with some experience gives good results both in radiography and histology. With this method the test lungs seemed to assume during fixation a fairly constant volume, a little higher than functional residual capacity.
Mortality from respiratory diseases in Finland in 1955--1973 was investigated using the official statistics and original death certificates. Total mortality from respiratory diseases in men was significantly higher than in women. Total respiratory mortality in men has increased slightly since 1963, whereas in women it decreased between 1955 and 1963 but has since remained almost constant. Mortality from lung cancer increased in men constantly in the years 1955--1973, but this was not found in women. Mortality from obstructive lung diseases in men increased slightly between 1955 and 1969 but not since. This increase was recorded only for the elderly whereas the opposite trend was found in younger people. The number of deaths from pneumonia decreased between 1955 and 1963. After 1963 these deaths increased again but only in the older age groups. Mortality from pulmonary tuberculosis showed a steady decrease. In 1973 the autopsy rate was 80.6% in pneumococcal pneumonia, 65.6% in pulmonary embolism, 48.1% in bronchiectasis, and 47.0% in pulmonary tuberculosis, exceeding significantly the mean national autopsy rate which was 38.3%. This might mean that at least some of these respiratory diseases are underdiagnosed clinically as the performance of an autopsy seems to increase their relative proportion in mortality statistics.
A total of 121 pleurodeses using instillations of quinacrine (mepacrine) in patients with recurrent pleural effusion were performed. All but three patients suffered from pleural malignancy. A comparison was made between the results achieved by repeated thoracenteses (73 cases) and by simultaneous tube drainage (48 cases). Tube drainage shortened the treatment and lowered the number of painful interventions. There was no difference in the quality of pleurodesis achieved by the two methods. The treatment failed in 12% of patients treated by repeated thoracenteses and in 14% of those treated by tube drainage. Patients with pleurodeses survive longer than non-treated subjects and have a considerably better quality of life.
We studied reinflation of collapsed parts in excised normal human lungs through both the ordinary bronchial route and through collateral channels. A model of atelectasis was made either by simple collapse or by applying a positive pressure to the pleura and a negative to the airway. Five different ventilatory patterns were used for reinflation: simulated normal breathing with and without continuous positive airway pressure (CPAP), simulated deep breathing and mechanical ventilation with and without positive end-expiratory pressure (PEEP). All methods, except normal breathing without CPAP, reinflated the collapsed part with pressures well within the range used clinically. The most effective way of re-expanding collapsed lung was the application of CPAP during simulated normal breathing or PEEP during mechanical ventilation, which required smaller transpulmonary pressure swings than the other methods. A comparison between CPAP and PEEP showed CPAP to be preferable. Collateral reinflation occurred just as readily as normal reinflation and the results suggest that collateral reinflation is the primary choice. This route of reexpansion also has a potential secretion clearing effect in that pressure is built up distal to an obstruction.
The nasal mucociliary transport was measured on 15 healthy test subjects, using the saccharine method, before and after exposure to hair-spray and Freon. The hair-spray reduced the mucociliary transport in the nose for more than 1 h, whereas Freon had no effect. Hair-spray must be considered potentially dangerous, and investigations of the mucociliary transport in persons subject to prolonged exposure to hair-spray (ladies' hairdressers) must be relevant.
Concentrations of azidocillin in serum and tracheobronchial secretions were followed in 20 patients after an oral dose of 0.75 g of the drug. Serum concentrations were followed for 4 h and the concentration in tracheobronchial secretion was determined in samples taken through a fibreoptic bronchoscope 1--2 h after administration. The concentration in secretions varied between hardly measurable levels and 1.1 micrograms/ml. No correlation between levels in serum and tracheobronchial secretion was found. A slight tendency to higher secretion levels was found when the bronchoscopy showed signs of tracheobronchitis.
Two laboratory techniques have been applied for the diagnosis and follow-up of pigeon breeders' disease, viz. detection of precipitins against specific antigens from pigeon droppings and assays of human haemolytic complement (huC) consumption by pigeon dropping antigens. A simple laboratory test of huC consumption by pigeon antigens is described, revealing high huC sensitivity in almost all sera of pigeon breeders with manifest or former disease. False-positive results were seldom observed. Discontinuation of antigen exposure and/or corticosteroid therapy had no effect on the huC consumption level in the test system, despite precipitin titres falling below the level of detection. Titration studies revealed an initial decrease of the huC-consuming serum factors, but titres settled at a definite constant level, even after antigen avoidance for many years. Combined application of both the precipitin test and the huC consumption test appears to be a good procedure for the laboratory diagnosis of pigeon breeders' disease.
Mucociliary clearance was measured in 19 healthy non-smoking male subjects, aged between 21 and 69, by analysing the decrease in bronchial radioactivity of an aerosol of resin particles (mean diameter 7.4 +/- 1.5 micrometers) labelled with 99mTc. The mucociliary clearance was expressed as the percentage of radioactivity eliminated after 1 h. The measurements were made on two occasions with an average time lapse of 5 weeks. The intra- and inter-individual coefficients of variation were 15.6% and 41.5% respectively. The mucociliary clearance was significantly lower (P less than 0.05) (mean 21.8 +/- s.d. 7.8%) in the older subjects (greater than 54 years) than that observed (mean 34.1 +/- s.d. 14.1%) in the younger subjects (21 to 37 years). A significant negative correlation (r=-0.472, P less than 0.05) was obtained between the ages of the healthy subjects and their mucociliary clearance. However, the fact that the results varied considerably within each age group suggests that factors other than age may have an effect on the mucociliary clearance.
Study of the relationship existing between in vivo and in vitro correlates of cell immunity has revealed that there is no marked correlation between the magnitude of skin induration of the tuberculin skin test and the degree of inhibition of migration of blood leukocytes stimulated by PPD in patients with newly detected, bacteriologically confirmed pulmonary tuberculosis.
Tablets containing 250 mg of microcrystalline theophylline were given at 6-hourly intervals for 6 days. Minimum plasma theophylline concentrations in eight patients averaged 36.6 +/- 5.4 mumol/l (1 mumol = 0.18 mg), and the corresponding maximum concentration were 81.8 +/- 10.6 mumol/l. In 11 patients, studied after a single 250 mg dose, significant improvements in PEF and FEV1 were observed, in spite of maximum concentrations averaging only 38.8 +/- 2.2 mumol/l, which is below the commonly regarded lower limits of the therapeutic range. Nine of the 11 patients complained of side effects and in three patients a reduction in dose was necessary. In four volunteers given a single dose of 250 mg the plasma concentration of theophylline were not particularly affected by whether the tablets were taken fasting or postprandial.
The effects of oral administration of the guaiacolic ester of acetylsalicylic acid (ASA-G) on the ventilatory function were studied by means of a body plethysmograph, in a group of nine ASA-asthmatic patients. No differences in specific airway resistance were observed between ASA-G and placebo. It is concluded that ASA-G is tolerated by patients with ASA-induced asthma.
Pulmonary function in Behçet's syndrome has not received much attention, although sporadic cases of airways obstruction have been described. In this series of five cases one had abnormal results with reversible airways obstruction and emphysema. These findings were likely to have been associated with asthma, previous smoking habits and pulmonary tuberculosis, and not another manifestation of Behçet's syndrome.
