Polymorphism of the angiotensin-converting enzyme gene affects the outcome of acute respiratory distress syndrome.
OBJECTIVE
There has been increasing evidence that angiotensin II may play an important role in the pathogenesis and in the evolution of acute lung injury. It was therefore hypothesized that polymorphisms of the angiotensin-converting enzyme gene affects the risk and outcome of acute respiratory distress syndrome (ARDS).


METHODS
Prospective, observational study.


METHODS
The ARDS group consisted of 101 patients treated at the medical intensive care unit; the control groups consisted of 138 "at-risk" patients treated at the medical intensive care unit due to acute respiratory failure but did not meet the ARDS criteria throughout the hospital course, and 210 non-at-risk subjects.


METHODS
None.


RESULTS
The ARDS patients and control subjects were genotyped for the insertion/deletion (I/D) polymorphism of the angiotensin-converting enzyme gene. Association of the polymorphism and the risk and the outcome of ARDS was analyzed. There was no significant difference in the frequencies of the genotypes between the ARDS, at-risk, and non-at-risk groups. The 28-day mortality rates were significantly different between the three angiotensin-converting enzyme genotypes (42%, 65%, and 75% for II, ID, and DD, respectively; p = .036). Survival analysis showed that the II genotype favorably affected 28-day survival (hazard ratio, 0.46; 95% confidence interval, 0.26-0.81; p = .007), whereas ARDS caused by hospital-acquired pneumonia had a negative effect (hazard ratio, 2.34; 95% confidence interval, 1.25-4.40; p = .008). The II genotype (hazard ratio, 0.53; 95% confidence interval, 0.32-0.87; p = .012) and ARDS caused by hospital-acquired pneumonia (hazard ratio, 2.13; 95% confidence interval, 1.24-3.68; p = .006) were also significant prognostic factors for the in-hospital mortality.


CONCLUSIONS
The angiotensin-converting enzyme I/D polymorphism is a significant prognostic factor for the outcome of ARDS. Patients with the II genotype have a significantly better chance of survival. This study did not show an increased risk for ARDS in Chinese patients with the D allele.
Department of Internal Medicine, National Taiwan University Hospital, Taipei.
Jih-Shuin
JS
Jerng
Chong-Jen
CJ
Yu
Hao-Chien
HC
Wang
Kuan-Yu
KY
Chen
Shih-Lung
SL
Cheng
Pan-Chyr
PC
Yang
D002681:China; D005260:Female; D005838:Genotype; D006801:Humans; D008297:Male; D008875:Middle Aged; D007703:Peptidyl-Dipeptidase A / Q000235:genetics*; D011110:Polymorphism, Genetic; D011446:Prospective Studies; D012128:Respiratory Distress Syndrome / Q000235:genetics* / Q000628:therapy*; D012307:Risk Factors; D016896:Treatment Outcome
D007703:Peptidyl-Dipeptidase A