Page 27 - ADULT-ONSET ASTHMA PREDICTORS OF CLINICAL COURSE AND SEVERITY

persistent air ow limita on and male gender (OR, 4.5; 95% CI, 2.3 to 8.5); older age (OR per 10 years, 1.4; 95% CI, 1.3 to 1.6) and current or past smoking (OR, 3.9; 95% CI, 1.8 to 8.6; and OR, 1.6; 95% CI, 1.2 to 2.3, respec vely) 45. Perret et al., also found an associa on between smoking and persistent air ow limita on, but this was limited to pa ents with atopy 46.
DETERMINANTS OF LUNG FUNCTION IN OCCUPATIONAL ASTHMA
Studies inves ga ng occupa onal asthma reported the lung func on decline in these pa ents is mostly in uenced by con nued exposure. A study by Anees et al., showed no in uence of gender or baseline FEV1 but decline in lung func on was associated with con nued exposure to the causa ve agent 47. Just a er removal from exposure, the pa ents had an upli in FEV1, followed by a subsequent decline at lower rate than during exposure 47. Other studies also showed a steeper decline in lung func on with an irregular slope in the groups that con nued being exposed compared to the group that avoided exposure 47-49. The rela onship between bronchial hyperresponsiveness (BHR) and removal from exposure is less clear. One study showed a correla on between me of removal and improvement in BHR 50, whereas another study showed persistent hyperresponsiveness a er 10 years of removal 51.
THE PROGNOSIS OF ADULT-ONSET ASTHMA
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