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OBJECTIVE: Airflow obstruction is relatively uncommon in young adults, and may indicate potential for the development of progressive disease. The objective of the present study was to enumerate and characterize airflow obstruction in a random sample of Canadians aged 20 to 44 years.

BACKGROUND:Standard methods for population studies of asthma include surveying population samples using questionnaires and examining people in laboratories. These procedures are extremely expensive. It would be helpful if, at least for some purposes, they could be replaced by cheaper techniques with adequate validity. OBJECTIVES: To determine agreement between survey and database in regard to the prevalence of asthma.

In this issue of the Canadian Respiratory Journal, Gulmez et al (pages 287-290) review the presentation, management and outcome of malignant mesothelioma in central Anatolia, Turkey. There is nothing particularly new about the disease here; it presents with chest pain, dyspnea and pleural effusion, is diagnosed by biopsy and has a miserable outcome whatever is done for it, just like malignant mesothelioma in Canada. Mesothelioma in Anatolia is unusual in that it is very common, with an approximately equal sex distribution, and frequently occurs in relatively young people. The reasons for this are not a mystery. Anatolia is a volcanic area; there is a lot of asbestos on or near the surface, and it is widely used as construction material, in painting, and as insulation (pages 287-290)! Asbestos related disease is due to environmental, not occupational exposure, and exposure is more intense and occurs at an earlier age than in Canada. Not only that, but some areas of Anatolia are rich in erionite, and people build homes in and on erionite-bearing rocks. Erionite is apparently something like asbestos but worse in terms of carcinogenicity (1), perhaps because its crystals have large surface areas, and areas with erionite have an even higher incidence of mesothelioma.

In this issue of the Canadian Respiratory Journal, Cowie et al (pages 555-558) make the startling claim that "inhaled corticosteroid therapy does not control asthma". This sounds crazy: if inhaled steroids don't control asthma, what does? It turns out not to be crazy. Cowie et al reported on the effectiveness of asthma control according to Canadian guidelines (1) in several large groups of asthmatics evaluated by cross-sectional, one-point-in-time questionnaires. They found that patients on inhaled steroids were less well-controlled than those who were not on inhaled steroids, and that there was a dose effect, in that the larger the dose of inhaled steroids the worse the control. There is, of course, a simple explanation for this; patients with hard-to-control asthma are likely to be prescribed inhaled steroids, and the harder the disease is to control, the higher the dose. However, these findings are compatible with inhaled steroids having a minor effect on asthma control, something that we do not believe (2). There are excellent data from clinical trials (3) that inhaled steroids work, and in population studies (4), their use is associated with improved survival.

In this issue of the Canadian Respiratory Journal, Gutierrez et al (pages 414-424) present normal lung function values and prediction equations for white Canadians. They had six laboratories across the country each test approximately 100 volunteer, nonsmoking white adults (the target was 120 each), with appropriate variation in age and sex. Adequate representation of different ages and sex were obtained, although it appeared to be harder to recruit elderly men than elderly women. A full battery of tests was performed on each person. The equipment was not standardized and varied from centre to centre, and some centres performed slightly different tests than others; in other words, the study was done under field conditions. The results were analyzed for each centre and pooled to produce the Canadian model. This was compared with several similar models developed in Europe and the United States (1-5).

In this issue of the Canadian Respiratory Journal, Demeter et al (pages 435-441) describe lung cancer outcomes in a recent Alberta cohort. Not much is new; outcomes are bad, not much better than they were when I was in medical school more than 40 years ago. This is a particularly sad state of affairs in view of the fact that lung cancer is a self-inflicted phenomenon related to smoking. Further, this has been known for 40 years, and only recently have lung cancer rates levelled off in men, though they have continued to increase in women.