Uric Acid and Hypertension in African Americans

• Status: Completed
• Trial end date: 2011-05-01
• Target enrollment: 0
• Participant gender: All

Summary

This study will test the hypothesis that the administration of a xanthine oxidase inhibitor (allopurinol) will prevent thiazide-induced hyperuricemia, which will result in better blood pressure (BP) control in African Americans.

• Phase: Phase 3
• Accepts Healthy Volunteers?: No

Details

• Lead Sponsor: University of Florida
• Treatments: Allopurinol; Chlorthalidone; Uric Acid

Criteria

Inclusion Criteria:

• African American (including black individuals born in the Caribbean, Africa, Canada, etc.)

• Are either untreated with any antihypertensive agent, with an average sitting clinic BP of between 140/90 and 159/99 mm Hg OR subjects with hypertension controlled (i.e. BP less than 140/90) or no higher than stage 1 hypertension (i.e., less than 160/100) on a single antihypertensive agent or two antihypertensive agents (individuals on fixed dose ARB-diuretic or ACEI-diuretic combinations will also be considered as being on monotherapy for purposes of the study. Individuals on beta blockade or calcium channel blockade for coronary artery disease and/or arrhythmia will not be eligible for the study)

• Random spot urine protein/creatinine ratio of less than 0.5 (approximates a 24-hour urinary protein excretion of 500 mg/day)

• Calculated MDRD GFR of greater than or equal to 60 ml/min/1.73/m^2

• No allopurinol or probenecid intake for at least one month prior to study entry

• Willing and able to cooperate with study procedures

• Willing to travel to the GCRC at Shands Hospital for overnight inpatient stays on two separate occasions

Exclusion Criteria:

• History of malignant or accelerated hypertension

• Confirmed total white cell count of less than 2,500/mm^3, anemia, or thrombocytopenia

• Known history of liver disease

• Known secondary cause of hypertension

• Known presence of diabetes or fasting blood glucose greater than or equal to 126 mg/dL

• History of heart failure, acute myocardial infarction, or stroke or on a β-blocker or calcium channel blocker for cardiovascular indications other than for lowering blood pressure

• Abnormal EKG requiring medical intervention

• History of clinical or renal biopsy or evidence of renal parenchymal disease

• Acute gout attack within 2 weeks of study entry

• History of drug abuse in the last 2 years, including narcotics, cocaine, or alcohol (greater than 21 drinks/week)

• Arm circumference of greater than 52 cm, which precludes measurement with a 'thigh' BP cuff

• History of a reaction to allopurinol or chlorthalidone

• Pregnant or planning to become pregnant during the study, or breastfeeding

• History of noncompliance, are unable to comply with the study requirements, or who are currently participating in another study

• Not fasting prior to obtaining screening laboratory data. If a participant has clearly not fasted, we will exclude those individuals with casual blood glucose levels of greater than or equal to 200 mg/dL. In the event that a fasting blood sugar exceeds 126 mg/dL, it will be reconfirmed on a blood glucose measurement obtained on a subsequent day, per American Diabetes Association criteria