Treatment Status - Table 2

Statistical Analyses:
Comparability at baseline was assessed by chi-square test for categorical variables and the t-test for continuous variables. Cumulative event rates were calculated using life table methods. All analyses were by treatment assignment at randomization. A Data and Safety Monitoring Board met twice a year to review unblinded data on efficacy and safety, and to evaluate whether the trial should be stopped early.

Treatment Status During the Follow-up Period:
About 90% of persons in the active treatment group remained on treatment during the trial (Table 2). An increasing proportion of the placebo group was placed on treatment as the trial progressed (Table 2).

Treatment Status among Groups, (%) by Year
Year   Active Treatment Placebo
1 90 19
2 89 29
3 89 37
4 90 41
5 90 46

This treatment pattern was reflected in the trends in blood pressure (Table 3).