In addition, no difference existed between the > 5 ng kg−1 min−1 angiotensin II subgroup and the ≤ 5 ng kg−1 min−1 angiotensin II subgroup in characteristics potentially associated with impaired production/function of angiotensin II (such as prior use of angiotensin-converting enzyme inhibitors, use of angiotensin II receptor blockers, or radiographic evidence of ARDS; Table 1). This evidence concerns the gene ACE and acute respiratory distress syndrome.