TABLE 5

Multivariable-adjusted* HRs of developing diabetes comparing quartiles of IL-18 levels stratified by sex, BMI, smoking status, physical activity, and parental history of diabetes

Quartile of IL-18
1234P value for trendP value for interaction
Median (lower, upper limit) (pg/ml)n80.09 (4.9, 116.7)145.18 (116.8, 173.5)205.04 (173.6, 244.6)322.08 (244.7, 8,792.4)
Sex
    Men1,1941.01.07 (0.67–1.69)1.48 (0.97–2.24)1.45 (0.95–2.21)0.0610.707
    Women1,0311.01.17 (0.67–2.04)1.54 (0.88–2.71)2.06 (1.21–3.52)0.003
BMI (kg/m2)
    <256591.01.02 (0.36–2.90)0.94 (0.30–2.94)2.33 (0.93–5.85)0.0310.986
    25 to <301,0061.01.22 (0.75–1.97)1.60 (1.02–2.52)1.49 (0.94–2.36)0.083
    ≥305601.01.05 (0.60–1.83)1.82 (1.07–3.09)1.84 (1.07–3.17)0.008
Smoking status
    Never smoker1,0111.01.24 (0.72–2.13)1.65 (0.95–2.88)1.88 (1.10–3.22)0.0130.886
    Former smoker6511.01.13 (0.61–2.08)1.31 (0.76–2.26)1.36 (0.77–2.39)0.277
    Current smoker5631.00.92 (0.42–2.02)1.86 (0.92–3.76)1.90 (0.93–3.91)0.028
Frequency of exercise
    Inactive1,3911.01.00 (0.65–1.52)1.60 (1.07–2.39)1.53 (1.03–2.27)0.0130.645
    Active8341.01.64 (0.88–3.08)1.95 (1.05–3.64)2.40 (1.30–4.43)0.006
Parental history of diabetes
    Negative1,2481.01.02 (0.61–1.72)1.60 (1.00–2.57)1.96 (1.26–3.06)0.0010.597
    Positive4851.01.40 (0.68–2.91)2.00 (0.97–4.13)2.61 (1.25–5.44)0.006
    Unknown4921.00.91 (0.46–1.82)1.35 (0.68–2.67)0.97 (0.50–1.90)0.976
  • Data are median ranges (lower, upper limits) or HRs (95% CIs).

  • *

    * Models were adjusted for age, sex, survey, BMI, systolic blood pressure, ratio of total cholesterol to HDL cholesterol, physical activity, alcohol intake, smoking status, and parental history of diabetes.

  • BMI was included as a continuous variable in the main effects model and in the model with the interaction term.