Table 2. Total and stratified analysis of nitric oxide synthase 3 polymorphisms and the preeclampsia risk.
| Summary | Na | Cases/Controls | OR (95%CI) | Cochran Q | I2, % | P for Z testb |
|---|---|---|---|---|---|---|
| G894T | ||||||
| Total | 30 | 3,503/6,843 | 1.46 (1.21, 1.77) | 41.83 | 40.2 | <0.001 |
| Ethnicity | ||||||
| Caucasian | 20 | 2,108/5,020 | 1.29 (0.90, 1.85) | 39.84 | 52.2 | 0.173 |
| Asian | 8 | 863/1,099 | 1.77 (0.88, 3.55) | 2.47 | 0.0 | 0.108 |
| African | 4 | 219/318 | 1.81 (0.43, 7.58) | 1.49 | 0.0 | 0.416 |
| Mixedc | 2 | 311/431 | 2.23 (0.43, 11.55) | 5.35 | 81.2 | 0.339 |
| Score | ||||||
| Low | 15 | 1,244/1,866 | 1.22 (0.87, 1.72) | 14.22 | 29.7 | 0.240 |
| High | 15 | 2,259/4,977 | 1.59 (1.27, 2.00) | 26.64 | 47.4 | <0.001 |
| Sensitivity analysis | ||||||
| Maximal | 29 | −/− | 1.53 (1.26, 1.86) | 31.94 | 36.0 | <0.001 |
| Minimal | 29 | −/− | 1.35 (1.11, 1.64) | 23.69 | 24.9 | 0.003 |
| T-786C | ||||||
| Total | 15 | 2,232/3,068 | 1.30 (1.07, 1.58) | 26.32 | 46.9 | 0.008 |
| Ethnicity | ||||||
| Caucasian | 10 | 1,227/2,115 | 1.41 (1.11, 1.79) | 19.53 | 53.5 | 0.005 |
| Asian | 3 | 538/534 | 0.89 (0.55, 1.45) | 0.43 | 0.0 | 0.641 |
| African | 2 | 369/312 | 2.44 (1.26, 4.71) | 0.18 | 0.0 | 0.008 |
| Mixedc | 1 | 98/107 | 0.80 (0.32, 1.99) | 0.00 | − | 0.632 |
| Score | ||||||
| Low | 5 | 591/833 | 1.08 (0.79, 1.47) | 8.43 | 52.5 | 0.636 |
| High | 10 | 1,641/2,235 | 1.47 (1.14, 1.89) | 16.03 | 43.9 | 0.003 |
| Sensitivity analysis | ||||||
| Maximal | 14 | −/− | 1.37 (1.12, 1.69) | 22.79 | 45.9 | 0.003 |
| Minimal | 14 | −/− | 1.22 (1.01, 1.49) | 20.57 | 43.0 | 0.045 |
OR: odds ratio; CI: confidence interval;
aNumber of studies.
bP-value of Z-test for significance.
cMixed ethnicity included both Caucasians and Africans.