Phase 3
N=142
Uric Acid and Hypertension in African Americans
Cardiovascular Diseases · Heart Diseases · Hypertension
Bottom Line
View on ClinicalTrials.gov: NCT00241839 ↗Enrolled (actual)
142
Serious AEs
4.9%
Results posted
Jul 2013
Primary outcome: Primary: Change in Diastolic Blood Pressure by Cuff 8-10 Weeks Minus Baseline — 3.44; -0.83 mm Hg — p=0.059
Study Design & Population
- Study type
- Interventional
- Phase
- Phase 3
- Interventions
- Allopurinol (Drug); Placebo (Drug); Chlorthalidone (Drug); Potassium chloride (Drug)
- Age
- Adult, Older Adult · 18+ yrs
- Sex
- All
- Sponsor
- University of Florida
- Primary completion
- May 2011
Outcome Measures
| Outcome | Result | p-value |
|---|---|---|
| PRIMARY Change in Diastolic Blood Pressure by Cuff 8-10 Weeks Minus Baseline |
3.44; -0.83 | 0.059 |
| PRIMARY Change in Systolic Blood Pressure by Cuff After 8-10 Weeks Minus Baseline |
0.21; -0.95 | 0.47 |
| SECONDARY Change in Overall Mean BP From Those Obtained by 24 Hour Ambulatory Blood Pressure Measurements (ABPM) 8-10 Weeks Minus Baseline. |
-5.9; 0.90 | 0.0020 sig |
| SECONDARY Change in Uric Acid (UA) Levels: Baseline Less End of Treatment |
2.29; 0.14 | <0.001 sig |
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.
Eligibility 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
Data sourced from ClinicalTrials.gov (NCT00241839). Outcome figures and adverse-event rates are extracted automatically from the registry's posted results and are provided for clinician reference, not as a substitute for the primary publication.