Table 4.
Subgroup analysis of MetS for the highest vs. lowest circulating vitamin E level category.
| Stratification | Number of studies | Pooled RR | 95% CI | P value | Heterogeneity |
|---|---|---|---|---|---|
| All studies | 5 | 1.46 | 0.85, 2.48 | P = 0.17 | P = 0.001; I2 = 75% |
| Adjustment of BMI | |||||
| Adjusted | 2 | 1.84 | 0.78, 4.38 | P = 0.16 | P = 0.05; I2 = 67% |
| Unadjusted | 3 | 1.07 | 0.77, 1.49 | P = 0.67 | P = 0.75; I2 = 0% |
| Adjustment of physical activity | |||||
| Adjusted | 2 | 1.84 | 0.78, 4.38 | P = 0.16 | P = 0.05; I2 = 67% |
| Unadjusted | 3 | 1.07 | 0.77, 1.49 | P = 0.67 | P = 0.75; I2 = 0% |
| Adjustment of energy intake | |||||
| Adjusted | 2 | 1.11 | 0.61, 2.04 | P = 0.73 | P = 0.28; I2 = 21% |
| Unadjusted | 3 | 1.62 | 0.79, 3.35 | P = 0.19 | P < 0.001; I2 = 87% |
| Adjustment for vitamin E supplement | |||||
| Adjusted | 2 | 1.11 | 0.61, 2.04 | P = 0.73 | P = 0.28; I2 = 21% |
| Unadjusted | 3 | 1.62 | 0.79, 3.35 | P = 0.19 | P < 0.001; I2 = 87% |
| Study design | |||||
| Cross-sectional | 4 | 1.65 | 0.94, 2.89 | P = 0.08 | P = 0.06; I2 = 55% |
| Cohort | 1 | 1.02 | 0.70, 1.49 | / | / |