Table 11. Stratified meta-analysis of eligible longitudinal studies by several study items related to study characteristics for pooled odds ratio (OR) of type 2 diabetes mellitus (DM) per 1 increment in risk alleles carried in relation to single nucleotide polymorphism (SNP).
| Item | Number of data |
OR (95% CI) | Q statistics | I-squared |
P value of heterogeneity |
Meta-regressiond | |
| Total | 21 | 1.10 (1.08–1.13) | 94.5 | 78.8% | <0.001 | ||
| Number of SNPs | <10 | 4 | 1.34 (1.21–1.49) | 4.6 | 35.2% | 0.20 | |
| ≥10 | 17 | 1.10 (1.07–1.12) | 74.8 | 78.6% | <0.001 | 0.005 | |
| Mean ageb | <50 years | 9 | 1.11 (1.06–1.14) | 28.6 | 72.0% | <0.001 | |
| ≥50 years | 11 | 1.11 (1.07–1.15) | 60.2 | 83.4% | <0.001 | 0.95 | |
| Proportion of men | <50% | 15 | 1.09 (1.06–1.12) | 65.3 | 78.6% | <0.001 | |
| ≥50% | 6 | 1.14 (1.09–1.20) | 21.3 | 76.6% | 0.00 | 0.19 | |
| Country | Western | 19 | 1.10 (1.08–1.13) | 91.1 | 80.2% | <0.001 | |
| Non-Western | 2 | 1.16 (1.05–1.29) | 2.1 | 51.3% | 0.15 | 0.40 | |
| Dominant ethnic Group | White | 15 | 1.10 (1.08–1.13) | 89.3 | 83.2% | <0.001 | |
| Non-White | 5 | 1.10 (1.06–1.13) | 5.2 | 23.1% | 0.27 | 0.94 | |
| Mean BMIa,b,c | <25 kg/m2 | 7 | 1.12 (1.08–1.17) | 15.6 | 61.5% | 0.02 | |
| ≥25 kg/m2 | 13 | 1.10 (1.07–1.13) | 75.8 | 84.2% | <0.001 | 0.5 | |
| Adjustment for BMI | Yes | 17 | 1.10 (1.08–1.13) | 63.0 | 74.6% | <0.001 | |
| No | 4 | 1.10 (1.05–1.16) | 18.5 | 83.8% | <0.001 | 0.96 | |
| Using OGTT to diagnose DM | Yes | 12 | 1.11 (1.07–1.15) | 41.5 | 73.5% | <0.001 | |
| No | 9 | 1.10 (1.06–1.13) | 45.1 | 82.3% | <0.001 | 0.80 | |
BMI, body mass index; OGTT, oral glucose tolerance test; IGT, impaired glucose tolerance; N/A, not applicable.
aIndicates mean BMI of study population at recruitment.
bOne study17 did not present data on mean age or BMI.
cIndicates mean BMI at the beginning of follow-up.
dP value for difference in the magnitude of logarithm of odds ratio between strata was indicated.