Respiratory symptoms as predictors of airways lability in an elderly population.

In an attempt to identify patterns of symptoms which might predict treatable airways obstruction in the elderly, we measured respiratory function and airways lability in 296 men and women aged 65 and over. Subjects were selected to represent eight symptom groups as ascertained in a postal survey of patients randomly selected from three general practice lists. Airways obstruction was strongly associated with smoking, but bronchial hyperresponsiveness to methacholine and reversibility of airways obstruction with salbutamol (measured when hyperresponsiveness could not be assessed) were not. There was evidence of bronchial hyperresponsiveness or salbutamol reversibility in 37% of symptomatic non-smokers. This points to a substantial component of obstructive lung disease in the elderly that is characterized by labile airways and unrelated to smoking. Symptoms of the 'bronchial irritability syndrome' were more strongly associated with airways lability than other symptoms, but their predictive value for airways lability (32%) was much lower than has been reported in younger adults.