Table 1. Omega-3 versus placebo (subgroups EPA dose).
| Overall effect | Heterogeneity | ||||||
|---|---|---|---|---|---|---|---|
| Outcome | No. of studies | No. of participants | Statistical method | Effect size[95%CI] | P | I2,% | P' |
| Glycemic control | |||||||
| FPG (mmol/L) | 17 | 990 | WMD (IV, Fixed) | 0.181[-0.022,0.385] | 0.081 | 0.0 | 0.964 |
| Low dose (<1.8 g/d EPA) [13,14,16–19,22,23,30] | 9 | 220 | WMD (IV, Fixed) | 0.165[-0.047,0.376] | 0.127 | 0.0 | 0.819 |
| High dose (≥1.8 g/d EPA) [20,24–29,32] | 8 | 770 | WMD (IV, Fixed) | 0.396[-0.364,1.157] | 0.307 | 0.0 | 0.910 |
| PPG (mmol/L) | 2 | 42 | WMD (IV, Fixed) | -1.036[-3.280,1.208] | 0.366 | 9.5 | 0.293 |
| Low dose (<1.8 g/d EPA) [19] | 1 | 16 | WMD (IV, Fixed) | -2.300[-5.555,0.955] | 0.166 | ― | ― |
| High dose (≥1.8 g/d EPA) [25] | 1 | 26 | WMD (IV, Fixed) | 0.110[-2.988,3.208] | 0.954 | ― | ― |
| HbAc1 (%) | 15 | 1179 | WMD (D+L, Random) | -0.050[-0.219,0.119] | 0.565 | 45.7 | 0.028 |
| Low dose (<1.8 g/d EPA) [14–19,22,23,30] | 9 | 999 | WMD (D+L, Random) | -0.103[-0.301,0.094] | 0.305 | 64.1 | 0.004 |
| High dose (≥1.8 g/d EPA) [20,24,25,28,29,32] | 6 | 180 | WMD (D+L, Random) | 0.266[-0.187,0.719] | 0.250 | 0.0 | 0.852 |
| INS (pmol/L) | 9 | 588 | WMD (D+L, Random) | -4.288[-10.911,2.335] | 0.204 | 2.8 | 0.411 |
| Low dose (<1.8 g/d EPA) [16,18,19,22,23] | 5 | 522 | WMD (D+L, Random) | -0.448[-11.760,10.863] | 0.938 | 49.4 | 0.095 |
| High dose (≥1.8 g/d EPA) [24,26–28] | 4 | 66 | WMD (D+L, Random) | -7.572[-23.717,8.572] | 0.358 | 0.0 | 0.983 |
| Lipid parameters | |||||||
| TG (mmol/L) | 12 | 703 | WMD (IV, Fixed) | -0.243[-0.339,-0.147] | <0.001 | 0.0 | 0.912 |
| Low dose (<1.8 g/d EPA) [13,15,17,22,23,30] | 6 | 535 | WMD (IV, Fixed) | -0.235[-0.338,-0.133] | <0.001 | 0.0 | 0.543 |
| High dose (≥1.8 g/d EPA) [24–27,29,32] | 6 | 168 | WMD (IV, Fixed) | -0.297[-0.564,-0.030] | 0.029 | 0.0 | 0.950 |
| TC(mmol/L) | 15 | 874 | WMD (IV, Fixed) | -0.023[-0.120,0.073] | 0.635 | 0.0 | 0.831 |
| Low dose (<1.8 g/d EPA) [13–17,22,23,30] | 8 | 666 | WMD (IV, Fixed) | -0.033[-0.138,0.073] | 0.542 | 0.0 | 0.544 |
| High dose (≥1.8 g/d EPA) [20,24–27,29,32] | 7 | 208 | WMD (IV, Fixed) | 0.024[-0.213,0.262] | 0.840 | 0.0 | 0.828 |
| BMI (kg/m2) | 3 | 392 | WMD (IV, Fixed) | 0.055[-0.800,0.909] | 0.900 | 0.0 | 0.947 |
| Low dose (<1.8 g/d EPA) [15,23,30] | 3 | 392 | WMD (IV, Fixed) | 0.055[-0.800,0.909] | 0.900 | 0.0 | 0.947 |
| Weight(kg) | 9 | 248 | WMD (IV, Fixed) | 0.365[-2.788,3.518] | 0.820 | 0.0 | 1.000 |
| Low dose (<1.8 g/d EPA) [17,22,30] | 3 | 90 | WMD (IV, Fixed) | 0.088[-6.030,6.206] | 0.977 | 0.0 | 0.977 |
| High dose (≥1.8 g/d EPA) [20,24,25,27–29] | 6 | 158 | WMD (IV, Fixed) | 0.466[-3.214,4.145] | 0.804 | 0.0 | 1.000 |
Notes: BMI, body mass index; FPG, fast plasma glucose; PPG, postprandial glucose; HbA1c, glycosylated hemoglobin; INS, insulin; TG, Triglyceride; TC, total cholesterol; WMD, weighted mean difference; IV, inverse variance; D+L, DerSimonian & Laird;-, not available.