Mixed models showed no need for initial response monitoring after starting antihypertensive therapy

Objective: To demonstrate how mixed models may be used to estimate treatment effects, and inform decision, on the need for monitoring initial response. Study Design and Setting: Mixed models were used to analyze data from the Perindopril Protection Against Recurrent Stroke Study (PROGRESS). which examined the effects Of perindopril and indapamide in 6 105 Patients at high risk of a cerebrovascular event. Results: The mean effect of perindopril was to lower blood pressure (BP) (systolic/diastolic) by 6/3 mmHg. The mean effect, of perindopril/indapamide varied according to baseline BP, and lowering of BP ranged front 9/5 to 14/5 mmHg (for individuals with a baseline systolic BP 140 and > 150 mmHg, respectively). We found no variation in the effects of treatment on BP for either perindopril alone or in combination with indapamide. The effects of treatment on the individual can be predicted from the mean effect of treatment for the group (perindopril) or baseline systolic BP subgroup (perindopril/indapamide). Conclusion: Monitoring initial treatment response is unneccessary for antihypertensives similar to those examined in this study. To ad(tress this issue for other therapies, we suggest that trials should report estimates of treatment effects from mixed models, and the CONSORT statement should be expanded to include this item. (C) 2009 Elsevier Inc. All rights reserved.