The corresponding HRs for amiodarone compared to placebo were 0.68 ( 95 % CI : 0.46 to 1.02 ) for the top , 0.86 ( 95 % CI : 0.61 to 1.21 ) for the middle , and 1.56 ( 95 % CI : 1.17 to 2.09 ) for the bottom tertile .