At baseline , interleukin-6 was independently associated with mortality , whereas both interleukin-6 levels ( hazard ratio = 1.23 [ 1.01-1 .49 ] ; p = 0.04 ) and procalcitonin levels ( hazard ratio = 1.20 [ 1.03-1 .39 ] ; p = 0.02 ) 24 hours after out-of-hospital cardiac arrest were associated with 30-day mortality with no interactions between targeted temperature management group and levels of interleukin-6 ( p = 0.25 ) or procalcitonin ( p = 0.85 ) .