INVEST substudies: Design and patient characteristics

The INternational VEraparnil SR/trandolapril STudy (INVEST) will provide a large database of information. Proposed substudies for analysis include amb ulatory blood pressure monitoring (ABPM), depression, genotyping, atrial fi brillation, electrocardiogram (ECG), echocardiography, renal dysfunction, d iabetes, and cardiac care cost estimate. This paper reviews the design and status of several of the INVEST substudies. The ABPM substudy will obtain o bjective blood pressure recordings during daily life masked to both the pat ient and the investigator. Ambulatory blood pressure monitoring is ari espe cially useful technology because of the role of nocturnal hypertension and circadian blood pressure irregularities in the development of hypertensive disease. The depression substudy, which enrolled 2,393 patients in the Unit ed States, will report quality-of-life (QOL) data, including information re garding energy and fatigue. The genotyping substudy will provide genomic DN A samples from approximately 15,000 patients in the United States, includin g Puerto Rico. Many candidate genes will be examined for polymorphisms. tha t may predict outcomes and/or responses to various treatments.