Dexamethasone isonicotinate aerosol therapy in patients with chronic bronchial asthma.

Dexamethasone isonicotinate aerosols were used for the management of 106 patients (33 men, 73 women) with bronchial asthma (mean age 32.7 years); 62 of the patients were steroid-dependent (maintenance dose 1 to 25 mg prednisone/day for 0.5 to 11 years) at the start of the study. A diary of symptoms (including consumption of antiasthmatic drugs) was kept; physical examination and measurement of pulmonary function (peak flow rate, forced expiratory volume in one second) were performed during a one-to-four week control period, as well as at various intervals (up to 14 months) after the start of corticosteroid aerosol therapy. Clinical subjective and objective improvement was accompanied by a significant increase in ventilatory function indices (e.g. the FEV1.0 rose from a control average of 55.5% of predicted to 72% after 4 weeks and 85% after 12 months). The antiasthmatic drug consumption decreased markedly. Administration of systemic steroids could be withdrawn in 49 of the 62 steroid-dependent patients (79%); in the remaining 13 the dose was only lowered. The side-effects were minor (hoarseness of the voice, oropharyngeal candidosis), and limited to a few cases. It is concluded that bronchial asthma can be successfully controlled in four fifths of the patients by very low doses of dexamethasone isonicotinate aerosols, with practically no systemic effects.

Hypoxemia in chronic bronchitis and pulmonary emphysema.

The measurement of arterial blood oxygen tension (PaO2) in 54 patients with chronic nonspecific lung disease with a FEV1.0 of 1.51 or less, in a stable clinical state, at rest, indicated subnormal results to be more frequent among "bronchitics" (79 per cent with hypoxemia) than than among "emphysematous" patients (63 per cent with hypoxemia). The patients were classified according to a mixed clinical-roentgenologic-biological "score" (Nash et al., 1965). A significant correlation was found between PaO2 and the "emphysema score" (r=0.36; p less than 0.01). The average PaO2 was significantly (p less than 0.02) lower in "bronchitics" (65.5 +/- 8.8 mmHg; n = 14) as compared to the "emphysema" group (71.8 +/- 5.7; n = 19), in agreement with the data of the literature.

Arterial carbon dioxide tension and dyspnea in chronic bronchitis and pulmonary emphysema.

The severity of dyspnea (MRC scale) was confronted to the blood carbon dioxide tension (PaCO2) in 45 patients with chronic nonspecific lung disease having moderate or severe airway obstruction (FEV1.0 of less than 1.5 liters). The patients were classified as "bronchitic", "emphysematous" and "intermediate" using a 10- criterion (clinical, roentgenologic and biological) "emphysema score". No correlation between dyspnea grade and PaCO2 was found in "bronchitic" and "intermediate" patients; in the "emphysematous" subgroup PaCO2 tended to rise as dyspnea was more severe, but the linear correlation coefficient (r= +0.37) did not reach the significance threshold, which is high (0.468) for such a limited number of observations.

Breathlessness and blood oxygen tension in patients with chronic bronchitis and emphysema.

The dyspnea grade (MRC scale) was confronted with the arterial oxygen tension (PaO2) measured at rest in a group of 51 patients with chronic obstructive lung disease with moderate or severe impairment of ventilatory function (FEV 1.0 less than 1.5 1). For the group as a whole no correlation was found, but in the "bronchitic" subgroup (clinical-roentgenologic and biologic criteria) a tendency of PaO2 to decrease with the increase in dyspnea severity was apparent. The linear correlation coefficient did not attain the significance threshold owing to the limited number of observations (r = 0.46; p greater than 0.05).

Transfer factor for the lung, airway obstruction and hyperinflation in chronic bronchitis and emphysema.

The interrelationships of breath holding lung transfer factor (TCO) and transfer coefficient (KCO) with ventilatory obstruction (FEV1.0) and FEV1.0/VC) and hyperinflation (RV and RV/TLC) were studied in 37 patients with chronic nonspecific lung disease with a FEV1.0 of 1.5 litre or less classified as "bronchitic", "emphysematous" or "intermediate" according to Nash, Briscoe and Cournand (1965). No relationships could be found between TCO and airway obstruction or hyperinflation. KCO tended to decrease as RV increased (r=-0.26) and was weakly related to the FEV1.0/VC ratio in "intermediate" (r=0.34) and "emphysema" (r=0.29) patients but these relationships were nonsignificant.

Prevalence of respiratory symptoms in towns with different air pollution.

An epidemiologic study was carried out for the estimation of air pollution as a risk factor for chronic obstructive lung disease. The whole male population aged 40 to 60 years was investigated in a polluted and a non-polluted control town. The subjects with occupational exposure to dusts, gases and irritant vapours were discarded from the study. The prevalence of respiratory symptoms and of chronic bronchitis in the polluted town was twice that in the control (non-polluted) one. These results are discussed in the light of some previous investigations of the authors and of the available data in the literature.

Breathlessness and transfer factor for the lung in chronic obstructive lung disease.

The breath-holding CO transfer factor and transfer coefficient were correlated with the severity of dyspnea in 37 patients with moderate or severe obstructive lung disease FEV 1.0 less than 1.5 1) No correlation was evident when the whole group was considered. When the patients were subdivided into "bronchitics", "intermediate" and "emphysematous" a correlation between dyspnea severity and gas transfer appeared for the latter subgroup; this correlation was statistically significant for the transfer coefficient.