Evaluation of the Relationship between the Reduction of Serum Uric Acid Level and Control of Blood Pressure in Patients with Hypertension and Hyperuricemia

Hypertension is one of the most common diseases in the world causing mortality and morbidity; however it is not controlled well yet. Treatment of predisposing factors of hypertension can help to control this disease. Hyperuricemia is known as one of the risk factors of hypertension, but there are limited studies, whether reducing serum uric acid level can cause lowering high blood pressure or not. This study evaluated the effect of allopurinol -uric acid lowering drug- on uncontrolled hypertension in patients with hyperuricemia. This was a double-blind randomized clinical trial study on 50 patients with uncontrolled hypertension who also had hyperuricemia. After sex, age and body mass index (BMI) matching, the patients were divided to two groups: first group received 200 mg allopurinol daily and the second received placebo for two months. Systolic and diastolic blood pressure and serum uric acid level were measured at the start and end of study. Finally, the obtained data were analyzed using SPSS21 software. Allopurinol caused significant reduction in systolic (P = 0.0002) and diastolic (P = 0.0003) blood pressure. But, considering the age and sex, allopurinol is just significantly effective on lowering systolic and diastolic blood pressure in men older than 50 years, neither in men younger than 50 years nor in women. Treatment of hyperuricemia with allopurinol has positive effects on lowering blood pressure in men older than 50 years. It is not effective in men less than 50 years of age and in women.