Permanent respiratory impairment and upper airway symptoms despite clinical improvement in patients with reactive airways dysfunction syndrome.

We previously reported clinical findings for 19 patients who developed symptomatic airways hyperactivity following an acute exposure to an inhaled irritant and who were given the diagnosis of reactive airways dysfunction syndrome (RADS). We now report on nine of these patients who have been followed for a mean of 9 years, allowing assessment of function, symptoms, and comorbidity beyond the early phase of acute airway injury and inflammation. None of the patients have resolved their airway hyper-responsiveness and symptoms completely, although only in one subject, who had a premorbid history of asthma, has the condition progressed. A common feature has been sinusitis and other upper-airway symptoms. We conclude that in this group of patients, RADS presented in a consistent pattern regardless of the cause of airway injury, resolved only partially, even in subjects without a premorbid history of respiratory disease, and was associated with significant secondary morbidity, especially affecting the upper airway. This pattern was evident regardless of smoking status or age at time of exposure. We conclude that for these subjects, RADS was a distinct entity with a consistent natural history that conferred permanent impairment, but did generally improve somewhat over time.