Changes in blood pressure in a large cohort of elderly individuals: Study 3C.

Objective: Analysis of changes in blood pressure with a two-year interval, and of factors associated with this change, in a large cohort of elderly individuals.

Methods: Follow-up of a cohort of 9294 individuals aged 65 years and over recruited from the general population for Study 3C. Changes in blood pressure are defined as the difference in its averages between the inclusion visit and the follow-up visit at 2 years.