Abstract 2766: Racial Differences in Blood Pressure Response to Angiotensin Converting Enzyme Inhibitors in Children: An Analysis of 6 Pediatric Hypertension Trials
Background: The prevalence of pediatric systemic hypertension is increasing and angiotensin-converting enzyme inhibitors (ACEi) are frequently used as therapy; however, few antihypertensive therapies have been systematically studied in children. Although racial differences in response to ACEi are well-established in adults, no such studies have been performed in children. We sought to determine whether response to ACEi in children with hypertension varies by race.
Methods: We analyzed patient data from 6 placebo-controlled, dose-response trials of ACEi (benazepril-B, enalapril-E, fosinopril-F, lisinopril-L, quinapril-Q, ramipril-R) in children aged 6 –17 years for pediatric exclusivity. We had access to the patient-level data from the submissions provided by the company to FDA. We analyzed the data using linear regression for change in systolic (SBP) and diastolic blood pressure (DBP) from baseline in relation to race, weight, drug, and dosage.
Results: We evaluated 838 patients: B=85, E=101, F=221, L=102, Q=112, R=217. There were 363 white patients, 227 black patients, and 248 of mixed/other race; 64% were male. Analysis of individual trial results showed significantly lower dose response for SBP in black patients vs. white patients with drugs B, E, and F; and for DBP in black patients vs. white patients with drug E. When data were combined, compared to white patients, black patients had a significantly lower response (mean change from baseline) to all ACEi dosages compared to placebo for both SBP and DBP [SBP: white -8.8±11.4, black -6.3±9.9, other -7.9±10.2 mmHg; p<0.001, white patients vs. black patients] and DBP [DBP: white -6.9±9.9, black -3.2±9.3, other -6.0±9.9 mmHg; p=0.001, white patients vs. black patients]. The linear regression coefficient for lower dose response with black race was also significant when adjusted for weight (p<0.01).
Conclusion: Racial differences are seen in blood pressure response to ACEi in hypertensive children consistent with adult data. This racial variation could not have been demonstrated using individual studies and is only apparent when combining patient data across trials.