Abstract 12496: Relationship between Clinical Trial Site Enrollment With Participant Characteristics and Study Outcome -the HIJ-CREATE Sub-study
Background: It is increasingly common for clinical trials to have numerous sites in operation in order to enroll the required number of participants. As a result, baseline characteristics, protocol completion, and outcomes differed significantly among enrolling sites.
Aim: To evaluate the impact of differences of enrolling sites on baseline variables, protocol completion and study outcomes in a prospective trial conducted in highly selected institutes.
Methods: HIJ-CREATE was a multicenter, prospective, randomized, controlled study that compared the effects of candesartan-based therapy with those of non-ARB-based standard therapy on major adverse cardiac events (MACE) in hypertensive patients with coronary artery disease. In the present study, titration of antihypertensive agents was performed to reach the target blood pressure (BP) of ≤130/85 mmHg. The primary endpoint was the time to the first occurrence of MACE. Incidence of MACEs in addition to biochemistry tests and office BP was determined during the scheduled 6, 12, 24, 36, 48, and 60 month visits. A total of 2049 patients were randomized in 14 clinical centers. Participants were grouped on the basis of total enrollment into 100 > (group L), 100-200 (group L-M), 200-300 (group H-M), and > 300 participants (group H) per site and were compared for outcomes.
Results: During a median follow-up of 4.2 years (follow-up rate of 99.6%), the primary outcome occurred in 552 patients (26.9%). The average of systolic BP was significantly lower in L-M group (131.8mmHg) than those of other 3 groups (135.3, 134.2, and 133.1, respectively). On the other hand, the H-M group patients have the highest incidence of MACE among 4 groups (Figure).
Conclusions: Even in the contemporary prospective multi-center trial conducted in well-selected institutes, the characteristics of each hospital may affect both therapeutic performances and clinical outcomes.
- © 2013 by American Heart Association, Inc.