Dry cough is the most common adverse reaction of angiotensin converting enzyme, including enalapril, in Chinese population. Clinical observations suggest that the incidence of ACEI-induced dry cough is different between Chinese and other racial groups, however, there is still lack of research data in Chinese. Stroke is the second leading cause of death in the world and leading cause of death in China. Except the known risk factor such as hypertension, high homocysteine level, folic acid deficiency, the impact of genetics should not be ignored.

In this study, we will investigate whether there are specific genotypes which may predict the incidence of (1)enalapril-induced dry cough in Chinese and (2)first stroke in hypertensive patients taking enalapril or enalapril-folic acid therapy, so as to provide a basis for developing guidelines on precision medication in enalapril therapy apply to Chinese population.

Inclusion Criteria:

• Patients taking enalapril or enalapril-folic acid therapy
• Signed informed consent.

Exclusion Criteria:

• Patients not taking enalapril treated
• Intolerance or unwillingness to blood sample collection.

Chinese Patients:In accordance with anti-hypertension indications of enalapril