High prevalence of persistent cough with angiotensin converting enzyme inhibitors in Chinese.

1. Angiotensin converting enzyme (ACE) inhibitors are in common use for the treatment of hypertension and heart failure. Whereas they are, in general, well tolerated, a dry cough can develop which, on occasion, requires termination of therapy. The reported prevalence of cough with ACE inhibitor therapy has varied from 0.2 to 25%, depending upon methods of data collection, analysis and symptom reporting. 2. To evaluate the prevalence of cough in Chinese patients receiving ACE inhibitors, interviews were carried out in 191 patients in Hong Kong who were taking therapy which included captopril or enalapril for hypertension or heart failure, and 382 patients matched for sex and age receiving alternative medications which excluded an ACE inhibitor (controls). Patients and controls were interviewed in a blinded manner by the same interviewer using a common adverse-effect questionnaire. 3. Persistent cough was reported in 44% of patients taking an ACE inhibitor (46% of those receiving captopril and 41.8% of patients taking enalapril), and in 11.1% of the controls (P < 0.001). The prevalence of other adverse reactions was similar, with no significant difference between the two treatment groups. The complication of cough was not related significantly to age, sex, underlying disease, drug dosage or smoking status. 4. This study indicates that cough is a common side effect of treatment with ACE inhibitors in Hong Kong Chinese, although in most patients cessation of therapy is not required. Whether Chinese are particularly susceptible to ACE-inhibitor cough requires a formal prospective study comparing Chinese and non-Chinese patients.