Objective-To study the health, employment, and financial outcome of occupational asthma.Design-A follow up study of workers with confirmed occupational asthma.Setting-A specialist occupational lung disease clinic.Subjects-All workers had a diagnosis of occupational asthma made at least one year earlier. Diagnosis was confirmed by serial peak expiratory flow measurement, specific bronchial provocation testing, or specific inununology.Main outcome measures-Respiratory symptoms, medication, pulmonary function, employment state, and financial position.Results-112 of a total of 140 eligible workers were followed up. 32% of patients remained exposed to the causative agent. These workers had more symptoms at follow up than those removed and a greater number were taking inhaled steroids. Continued exposure was also associated with a fall in % predicted forced expiratory volume in one second (FEV,) of 3% compared with that at presentation. Their median loss of annual income due to occupational asthma was 35%. Those removed from exposure were worse off financially (median loss 54% of annual income), had fewer respiratory symptoms than the group who remained exposed, and their % predicted FEV, had improved by 4-6%.

Twenty five patients who were exposed to oil mists at their place of work were investigated for possible work related asthma. Serial peak expiratory flow recordings showed 13 to have definite work related asthma, seven equivocal work related asthma, and three asthma unrelated to work; two had normal recordings.

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A study was carried out to examine the independence from starting prebronchodilator FEV1 of four indices commonly used to express airflow (FEV,) reversibility in response to bronchodilators. In 121 patients with chronic airflow obstruction with a mean prebron- chodilator circumstances be a more appropriate index of reversibility.4 This conclusion, however, was based on the results of a single test of response to an anticholinergic agent in a well defined homogeneous group of patients. We have examined the relation of this index and three other commonly used indices of reversibility in response to the prebronchodilator FEV, in a heterogeneous group of patients with chronic airflow obstruction, measuring the response to both an anticholinergic agent, ipratropium bromide, and a /2 agonist, salbutamol. MethodsOne hundred and twenty one outpatients, with a diagnosis of non-asthmatic chronic airflow obstruction and an FEV, below 70% predicted, completed a trial to assess corticosteroid responsiveness.5 Reversibility of the FEV, in response to 500 pg ipratropium bromide and 10 mg salbutamol was measured on different days during the 14 day run in period, before any corticosteroid was administered. Patients were asked to refrain from inhaled bronchodilators for six hours and oral bronchodilators for 24 hours before the laboratory visit. Each drug was given diluted in 2 ml normal saline via an Inspiron Minineb driven by the same air compressor to dryness. FEV, was measured on a dry wedge spirometer (Vitalograph) before the drug was inhaled and 20 minutes (salbutamol) or 25 minutes (ipratropium) after nebulisation had finished. The mean of three technically satisfactory attempts within 10% or 100 ml (whichever was the smaller) was used for subsequent analysis.Reversibility

The transfer coefficient (Kco) was significantly lower in diabetic patients with microangiopathy than in a matched group without this complication. This may reflect microangiopathy in the pulmonary circulation.Diabetic microangiopathy is a generalised abnormality of small blood vessels characterised by thickening of the capillary basal lamina. Postmortem studies have shown similar changes in the lungs of patients with diabetes, and its presence is associated with evidence of microangiopathy in other organs.'Previous studies of lung function in patients with diabetes have found various abnormalities, including reduced gas transfer,23 decreased elasticity,4 and airflow obstruction.5 The cause ofthese abnormalities is not clear. It has been suggested that the changes in elasticity and gas transfer are due in part to microangiopathy in the lungs, but they have not been shown to be associated with diabetic complications elsewhere.2 We have re-examined the relation between gas transfer and microangiopathic complications in patients with diabetes mellitus. MethodsNine subjects (six male) with diabetes with either proliferative retinopathy (eight) or maculopathy (one) were matched for age, sex, height, and smoking history with nine diabetic patients without these features. None of them currently smoked or had clinical evidence of unrelated cardiorespiratory disease, and none was taking drugs known to have effects on the lungs. All patients gave written informed consent after the purpose of the study had been explained.Spirometry was performed with a dry wedge spirometer (Vitalograph), and lung volumes were determined by a closed circuit helium dilution technique. The mean of three technically satisfactory measurements of single breath carbon monoxide gas transfer (TLCO; Morgan Transfertest machine, model C) was used in the analysis. The transfer coefficient (Kco-TLcO corrected for alveolar volume (VA)) was calculated. All patients answered the standard Medical Research Council questionnaire on respiratory symptoms and had blood samples taken for estimation of haemoglobin

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Treatment of chronic obstructive pulmonary disease (COPD) with inhaled and oral corticosteroids is common, although their exact role is unclear. Previous studies suggest these drugs may reduce decline in lung function in this group of patients. We report a study investigating the effect of inhaled beclomethasone diproprionate (BDP) on lung function and symptoms in a group of patients with COPD. Treatment was given for 2 years, and the decline in FEV1 in individual patients calculated over this period. Ninety-eight patients were randomized for the study, 59 completing 2 years of treatment. Patients withdrawn had more severe airflow obstruction. Decline in FEV1, measured both prior to and after bronchodilator, was less in patients receiving inhaled BDP, although the differences failed to reach statistical significance except in a subgroup of patients with more severe airflow obstruction. Exacerbation rates were also reduced by inhaled BDP, but again the differences failed to reach conventional levels of statistical significance. The results of this study are consistent with previous published work, but further insight into the long-term role of corticosteroids in COPD await the publication of large studies which have recently been completed. Although the changes seen in this study and others are numerically small, the rate of decline in FEV1 returned to normal levels expected from age-related decline, and hence such treatment combined with other strategies may well have a significant role in the long-term treatment of this condition.

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