The International Database of Ambulatory blood pressure in relation to Cardiovascular Outcome (IDACO):: protocol and research perspectives

Objectives The International Database on Ambulatory Blood Pressure Monitoring (1993-1994) lacked a prospective dimension. We are constructing a new resource of longitudinal population studies to with great precision to what extent the ambulatory pressure improves risk stratification. Methods The acronym IDACO refers to the new International Database of Ambulatory blood pressure in relation to Cardiovascular Outcome. Eligible studies are population based, have fatal as well as nonfatal available for analysis, comply with ethical standards, have been previously published in peer-reviewed In a meta-analysis based on individual patient data, composite and cause-specific cardiovascular events will related to various indexes derived by ambulatory blood pressure monitoring. The analyses will be stratified by cohort and adjusted for the conventional blood and other cardiovascular risk factors. Results To date, the international database includes patients from four cohorts recruited in Copenhagen, Denmark (n = 2311), Noorderkempen, Belgium (n = Ohasama, Japan (n = 11535), and Uppsala, Sweden (n = 1221). In these four cohorts, during a total of 69 person-years of follow-up (median 9.3 years), 1026 patients died and 929 participants experienced a fatal nonfatal cardiovascular event. Follow-up in five other eligible cohorts, involving a total of 4027 participants, is still in progress. We expect that this follow-up will be completed by the end of 2007. Conclusion The international database of ambulatory blood pressure in relation to cardiovascular outcome will provide a shared resource to investigate risk stratification by ambulatory blood pressure monitoring to an extent not possible in any earlier individual study.