Elite athletes should be screened for EIA. EVH is a more sensitive challenge in asymptomatic athletes than sport specific and laboratory based challenges. If sporting governing bodies were to implement screening programmes to test athletes for EIA, EVH is the challenge of choice.

Peak expiratory flow rate (PEFR) has been recorded hourly or two-hourly from waking to sleeping in workers with respiratory symptoms who were exposed to isocyanate fumes at work. Twenty-three recordings averaging 33 days duration were recorded in 20 workers. Each worker was also admitted for bronchial provocation testing to toluene di-isocyanate (TDI) or diphenylmethane di-isocyanate (MDI) fumes or both. A final assessment of work-related asthma made from subsequent work exposure was compared with the results of bronchial provocation testing and a subjective assessment of the peak flow records. Both techniques were specific and sensitive.Physiological patterns of occupational asthma were defined from the records of PEFR. The most striking finding was the slow recovery from work-induced asthma. This commonly took several days to start and in one worker took 70 days to complete after leaving work. Several workers developed a pattern resembling fixed airways obstruction after repeated exposure at work. The consequences of these findings for the recording of symptoms of occupational asthma are discussed and recommendations are made for the recording of PEFR in workers in general.

Peak expiratory flow rate (PEFR) has been measured hourly from waking to sleeping in 29 workers with respiratory symptoms exposed to the fumes of soft soldering fluxes containing colophony (pine resin). Thirty-nine records of mean length 33 days have been analysed, and the results compared with the occupational history and bronchial provocation testing in the same workers. From (Schilling, 1956). Symptoms most severe on the first day of the working week are seen in a wide range of diseases where fever is prominent, and wheeze is often present. These include metal fume fever (Greenhow, 1862), humidifier fever (Pickering et al, 1976), meat wrapper's asthma (Sokol, 1973), feather picker's asthma (Plessner, 1960), and grain fever (Williams et al, 1964;Kleinfeld et al, 1968).Measurement of lung function before and after a working shift has formed the basis of objective tests for occupational asthma in the work situation. This has often been disappointing. Schoenberg and Mitchell (1975) (1979b) were able to show a fall in FEV1 of 10% or more over at least one of three work shifts in a third of a group of workers in an electronics factory, all of whom had symptoms highly suggestive of occupational asthma. Most workers with colophony sensitivity have immediate asthmatic reactions on bronchial provocation testing (Burge et al, 1978), which may explain these better 308 on 11 May 2018 by guest. Protected by copyright.

Bronchial provocation studies on 15 workers occupationally exposed to formaldehyde are described. The results show that formaldehyde exposure can cause asthmatic reactions, and suggest that these are sometimes due to hypersensitivity and sometimes to a direct irritant effect. Three workers had classical occupational asthma caused by formaldehyde fumes, which was likely to be due to hypersensitivity, with late asthmatic reactions following formaldehyde exposure. Six workers developed immediate asthmatic reactions, which were likely to be due to a direct irritant effect as the reactions were shorter in duration than those seen after soluble allergen exposure and were closely related to histamine reactivity. The breathing zone concentrations of formaldehyde required to elicit these irritant reactions (mean 4.8 mg/m3) were higher than those encountered in buildings recently insulated with urea formaldehyde foam, but within levels sometimes found in industry.

There is considerable concern about the adverse effects on the skeleton of loss of menstrual function as a result of athletic activity, as well as uncertainty as to how it should be managed clinically. In a pilot intervention study 34 elite middle and long-distance runners, aged 18-35 years, with menstrual irregularity due to their athletic activity were randomized to three groups: (A) to receive hormone replacement therapy (HRT) and 1000 mg calcium per day (n = 10), (B) to receive 1000 mg calcium per day (n = 14), (C) a control group who received no treatment (n = 10). Bone mineral density (BMD) was measured in the left hip and lumbar spine (L2-4) using dual-energy X-ray absorptiometry. Results were first analyzed according to whether menstruation returned, either naturally or secondary to HRT (EU), and compared with those from subjects who remained amenorrheic (AM). During the first year BMD increased in the EU group in Ward's triangle (3.8%) and the lumbar spine (4.1%; both P < 0.05). BMD fell in the AM group in all regions and the between-group differences were 5.6% (p < 0.02) in Ward's triangle, 5.8% (p < 0.02) in L2-4 and 3.9% in the trochanter (p < 0.05). An 'intention to treat' analysis was then performed. It was found that the mean relative improvement at 1 year in spinal BMD was only 1.5%, due to return of menses in some of the controls and withdrawals from treatment in the treatment group. In consequence, a trial designed to show, with 80% power and 5% significance, a measurable benefit in lumbar spine BMD resulting from allocation to HRT treatment would require about 1150 athletes with amenorrhea or oligomenorrhea. These numbers could be reduced substantially to 380 subjects by confining the trial to completely amenorrheic athletes, who in this study were less likely to regain menses. For these and other logistical reasons, an HRT trial in amenorrheic athletes could only be successfully organized through international collaboration. This study illustrates the major effects of treatment withdrawals and instability of menstrual status on the design of longitudinal studies on the bony effects of menstrual dysfunction prior to menopause.