Compared with normal responders , sensitive and highly sensitive responders spent greater proportions of time over-anticoagulated in the first @ days of treatment ( median @ % , IQR @-@ ; @ % , @-@ ; and @ % , @-@ ; ptrend < @ ) and had increased risks of bleeding with warfarin ( sensitive responders hazard ratio @ , @ % CI @-@ , p = @ ; highly sensitive responders @ , @-@ , p < @ ) .