Table 4 Longitudinal analysis of sleep duration and insomnia with the risk of metabolic syndrome and its components using generalized estimating equation models

Average sleep hours

OR (95%CI)

OR (95%CI)

OR (95%CI)

OR (95%CI) ^a

OR (95%CI)

OR (95%CI) ^a

 < 6

1.11 (0.83–1.53)

0.98 (0.70–1.37)

1.06 (0.75–1.49)

1.04 (0.74–1.48)

1.41 (1.03–1.92)

1.35 (1.01–1.91)

 6- < 7

1.16 (0.90–1.49)

1.11 (0.86–1.42)

0.92 (0.70–1.20)

0.85 (0.65–1.11)

1.26 (0.99- 1.61)

1.24 (0.97–1.58)

 7- < 8

ref

ref

ref

ref

ref

ref

 8- < 9

1.14 (0.82–1.59)

1.13 (0.82–1.59)

0.62 (0.41–0.93)

0.62 (0.41–0.94)

1.05 (0.75–1.45)

1.02 (0.73–1.42)

 ≥ 9

0.62 (0.22–1.78)

0.68 (0.23–1.90)

0.40 (0.11–1.42)

0.43 (0.12–1.54)

1.00 (0.41–2.45)

1.09 (0.45–2.66)

 > 2 h increase

1.27 (0.74–2.18)

1.15 (0.67–2.00)

0.83 (0.40–1.70)

0.82 (0.40–1.69)

1.22 (0.68–2.19)

1.20 (0.66–2.17)

 > 2 h decrease

1.62 (1.00–2.62)

1.47 (0.90–2.37)

0.55 (0.25–1.20)

0.55 (0.25–1.21)

1.41 (0.83–2.38)

1.39 (0.82–2.37)

Quality of sleep over time

 Stable restful

ref

ref

ref

ref

ref

ref

 Restful to insomnia

1.44 (1.04–1.99)

1.40 (1.01–1.94)

1.04 (0.70–1.53)

1.07 (0.72–1.59)

1.26 (0.91–1.74)

1.27 (0.91–1.77)

 Insomnia to restful

1.16 (0.84–1.61)

1.14 (0.82–1.58)

1.34 (0.95–1.89)

1.28 (0.90–1.82)

0.81 (0.57–1.14)

0.80 (0.57–1.14)

 Persistent insomnia

1.39 (1.07–1.82)

1.31 (0.99–1.73)

1.18 (0.86–1.61)

1.05 (0.75–1.47)

1.12 (0.87–1.46)

1.10 (0.84–1.46)

Fasting glucose ≥ 100 mg/dL

Triglycerides ≥ 150 mg/dL

HDL < 50 mg/dL

Average sleep hours

OR (95%CI)

OR (95%CI) ^a

OR (95%CI)

OR (95%CI) ^a

OR (95%CI)

OR (95%CI) ^a

 < 6

1.47 (0.87–2.49)

1.19 (0.90–1.59)

0.85 (0.62–1.17)

0.79 (0.57–1.09)

1.17 (0.81–1.68)

1.06 (0.73–153)

 6- < 7

1.10 (0.77–1.57)

1.06 (0.85–1.32)

0.92 (0.73–1.16)

0.89 (0.70–1.13)

1.28 (0.97–169)

1.26 (0.96–1.66)

 7- < 8

ref

ref

ref

ref

ref

ref

 8- < 9

0.97 (0.64–1.44)

1.09 (0.81–1.47)

0.88 (0.63–1.22)

0.88 (0.63–1.22)

1.23 (0.85–1.77)

1.26 (0.87–1.82)

 ≥ 9

1.09 (0.42–2.85)

1.46 (0.71–3.03)

0.56 (0.21–1.51)

0.56 (0.21–1.51)

1.19 (0.46–3.04)

1.26 (0.49–3.24)

 > 2 h increase

1.13 (0.62–2.06)

0.94 (0.57–1.56)

1.37 (0.84–2.23)

1.32 (0.81–2.15)

0.90 (0.44–1.85)

0.92 (0.45–1.90)

 > 2 h decrease

0.92 (0.54–1.55)

0.96 (0.60–1.54)

0.98 (0.59–1.62)

0.98 (0.59–1.62)

1.37 (0.77–2.43)

1.26 (0.70–2.29)

Quality of sleep over time

 Stable restful

ref

ref

ref

ref

ref

ref

 Restful to insomnia

1.22 (0.92–1.61)

1.24 (0.93–1.65)

1.51 (1.10–2.06)

1.48 (1.08–2.03)

1.07 (0.73–1.57)

1.00 (0.68–1.47)

 Insomnia to restful

1.21 (0.92–1.58)

1.20 (0.91–1.58)

0.92 (0.67–1.26)

0.92 (0.67–1.27)

0.99 (0.68–1.43)

1.06 (0.72–1.54)

 Persistent insomnia

1.21 (0.95–1.53)

1.21 (0.94–1.56)

0.96 (0.73–1.26)

0.96 (0.73–1.26)

1.28 (0.95–1.72)

1.25 (0.91–1.71)