In intent-to-treat analysis , participants receiving the combined supplement of multivitamins plus selenium had a significantly lower risk vs placebo of reaching CD4 cell count 250/L or less ( adjusted hazard ratio [ HR ] , 0.46 ; 95 % CI , 0.25-0 .85 ; P = .01 ; absolute event rate [ AER ] , 4.79 / 100 person-years ; censoring rate , 0.92 ; 17 events ; placebo AER , 9.22 / 100 person-years ; censoring rate , 0.85 ; 32 events ) .