Higher incidence of discontinuation of angiotensin converting enzyme inhibitors due to cough in black subjects.

OBJECTIVE: To compare the rates of discontinuation of angiotensin converting enzyme (ACE) inhibitors in patients with different racial and ethnic backgrounds.
METHODS: A registry from a tertiary hypertension clinic consisting of 892 patients who received their first-ever dose of ACE inhibitor therapy was examined. Surveillance for cough was prospective, systematic, and constant beginning in 1986 and routinely included a trial of sinusitis therapy, followed by withdrawal and rechallenge before discontinuation of drug.
RESULTS: The prevalence (per 100 patients) of cough requiring discontinuation of ACE inhibitor therapy was 62 of 644 (9.6 per 100) patients among black subjects compared with six of 248 (2.4 per 100) patients among others (odds ratio, 4.0; 95% confidence interval, 1.7 to 9.1; p < 0.001). There were no significant differences in discontinuation rates across the three most commonly used ACE inhibitors: captopril (6.6%; all black subjects), enalapril (6.1%; 94% black subjects), and lisinopril (7.3%; 90% black subjects). Cough was more common among women (70% of subjects). After adjustment (by backward stepwise multiple logistic regression analysis) for baseline differences, black subjects had a relative risk of 2.58 (95% confidence interval, 1.21 to 4.65; p = 0.01) of discontinuation of ACE inhibitor due to cough.
CONCLUSIONS: These data suggest that there may be a race- or ethnicity-related difference in the prevalence of cough attributed to ACE inhibitor therapy. Although a race-related difference in ACE gene polymorphism has been suggested, further work is necessary to define the biological reason and pathophysiology for such a difference.