Table 3

Causal association between genetically determined insomnia and potential mediators

TraitMethodnSNPBetaSEP valueMR-Egger intercept P
BMIMR Egger1500.0300.0530.5700.379
Weighted median1500.0610.0080.000
Inverse variance weighted1500.0750.0140.000
Simple mode1500.0670.0220.002
Weighted mode1500.0570.0160.001
Waist-to-hip ratioMR Egger120−0.0260.0530.6180.270
Weighted median1200.0380.0170.026
Inverse variance weighted1200.0310.0120.011
Simple mode1200.0800.0470.090
Weighted mode1200.0560.0450.215
Body fat percentageMR Egger1490.0060.0390.8800.123
Weighted median1490.0550.0080.000
Inverse variance weighted1490.0640.0110.000
Simple mode1490.0700.0210.001
Weighted mode1490.0610.0190.002
HbA1cMR Egger1170.0360.2630.8930.949
Weighted median1170.0480.0880.585
Inverse variance weighted1170.0190.0610.751
Simple mode117−0.1860.2460.450
Weighted mode117−0.0390.1880.836
Fasting blood glucoseMR Egger139−0.0700.0820.3940.476
Weighted median139−0.0140.0300.638
Inverse variance weighted139−0.0140.0210.513
Simple mode139−0.0090.0860.912
Weighted mode1390.0050.0820.951
Fasting blood insulinMR Egger139−0.1090.0980.2680.239
Weighted median139−0.0130.0350.702
Inverse variance weighted1390.0030.0250.908
Simple mode139−0.0960.1100.385
Weighted mode139−0.0660.0970.495
  • Insomnia is causally associated with BMI and body fat percentage (in bold).

  • BMI, body mass index; MR, Mendelian randomization; SNP, single-nucleotide polymorphism.