Comparison of cause distribution between elderly and non-elderly patients with chronic cough.

BACKGROUND

The causes of chronic cough in elderly patients have not been specifically investigated. Therefore, it remains to be determined whether chronic cough differs between elderly and non-elderly patients.

OBJECTIVES

To investigate the distribution of causes of chronic cough in elderly patients in comparison with etiologies of chronic cough observed in non-elderly patients.

METHODS

From 2,989 new patients presenting consecutively to the Department of Respiratory Medicine of the Tongji Hospital over a 1.5-year period, 287 patients with chronic cough were enrolled in the study. Patients aged > or =60 years were assigned to the elderly group. The elderly group comprised 104 patients and the non-elderly group the remaining 183 patients. The causes of cough were primarily evaluated according to a modification of Irwin's anatomic diagnostic protocol which included induced sputum cytology, verified by the specific therapy.

RESULTS

Cough-variant asthma (34.6 vs. 41.5%) and upper airway cough syndrome (19.3 vs. 23.5%) were the most common causes of chronic cough both in the elderly and non-elderly groups. The distribution of causes and frequency were significantly different between elderly and non-elderly groups: angiotensin-converting enzyme inhibitor (ACEI)-induced cough (16.3 vs. 1.7%, chi(2) value = 22.12, p < 0.001) and gastroesophageal reflux disease (GERD; 10.6 vs. 3.7%, chi(2) value = 5.14, p = 0.02) were more common in the elderly group.

CONCLUSIONS

A more frequent incidence of ACEI-induced cough and GERD is the distinctive feature in the cause distribution between elderly and non-elderly patients with chronic cough.