TABLE 1

Change in metabolic parameters over time

Predicted value (95% CI) at each time point
Case-control difference (P)Case-by-time interaction (P)
−18 months−12 months−6 monthsDiabetes incidenceLinear time effectNonlinear time effect
Glucose (mmol/l)
    Control4.81 (4.78–4.85)4.86 (4.83–4.90)4.88 (4.84–4.91)4.91 (4.87–4.95)
    Case5.96 (5.83–6.10)6.55 (6.40–6.70)6.18 (6.04–6.33)7.76 (7.58–7.94)<0.0001<0.0001<0.0001
ALT (units/l)
    Control22.9 (22.1–23.6)23.7 (22.9–24.5)23.5 (22.8–24.3)24.2 (23.4–25.0)
    Case26.5 (24.2–29.0)29.2 (26.7–31.9)29.9 (27.4–32.7)32.2 (29.5–35.2)<0.00010.00050.0062
AST (units/l)
    Control22.53 (22.09–22.98)22.77 (22.32–23.22)22.84 (22.40–23.30)23.16 (22.71–23.62)
    Case22.44 (21.08–23.89)23.51 (22.09–25.02)23.82 (22.38–25.35)24.17 (22.71–25.73)0.300.140.41
Cholesterol (mmol/l)
    Control6.42 (6.27–6.59)6.22 (6.07–6.38)6.21 (6.06–6.37)6.22 (6.06–6.38)
    Case6.52 (6.29–6.76)6.41 (6.18–6.64)6.40 (6.17–6.63)6.40 (6.18–6.64)0.0310.310.63
Triglycerides (mmol/l)
    Control1.64 (1.58–1.69)1.58 (1.52–1.63)1.61 (1.55–1.66)1.58 (1.53–1.64)
    Case2.21 (2.01–2.44)2.26 (2.05–2.49)2.16 (1.96–2.39)2.39 (2.17–2.64)<0.00010.0300.011
HDL cholesterol (mmol/l)
    Control1.18 (1.16–1.20)1.18 (1.16–1.20)1.17 (1.15–1.18)1.17 (1.15–1.19)
    Case1.07 (1.02–1.13)1.07 (1.02–1.13)1.06 (1.01–1.11)1.06 (1.01–1.11)0.00010.650.95
Weight (kg)
    Control76.6 (75.8–77.5)77.0 (76.2–77.9)77.3 (76.5–78.1)77.5 (76.7–78.4)
    Case84.7 (82.3–87.1)85.5 (83.2–87.9)85.4 (83.1–87.8)86.1 (83.7–88.4)<0.00010.310.39
SBP (mmHg)
    Control132.2 (131.0–133.5)131.8 (130.6–133.1)133.1 (131.8–134.3)132.7 (131.5–134.0)
    Case137.0 (133.7–140.4)139.1 (135.7–142.5)139.0 (135.6–142.4)138.8 (135.4–142.1)0.00010.680.54
DBP (mmHg)
    Control82.8 (82.2–83.4)82.7 (82.1–83.3)83.0 (82.4–83.6)82.9 (82.3–83.5)
    Case85.4 (83.5–87.3)86.9 (85.0–88.8)85.6 (83.7–87.5)86.9 (85.0–88.8)<0.00010.410.22
Albumin (g/l)
    Control45.5 (45.3–45.7)45.4 (45.2–45.6)45.7 (45.5–45.9)45.9 (45.7–46.1)
    Case45.4 (44.8–46.0)45.6 (45.0–46.2)45.9 (45.3–46.5)46.0 (45.4–46.6)0.570.540.80
WCC (109/l)
    Control6.27 (6.15–6.39); n = 6376.22 (6.10–6.34); n = 6166.26 (6.14–6.39); n = 5066.27 (6.14–6.40); n = 421
    Case7.01 (6.60–7.45); n = 616.96 (6.55–7.39); n = 596.92 (6.50–7.38); n = 517.14 (6.69–7.63); n = 44<0.00010.820.86
  • Data are predicted values (95% CI) for each outcome variable in case subjects and control participants at each time point from mixed effects models allowing for random cluster and individual effects, with P values testing for case-by-time interactions using both linear and nonlinear time effects. Overall case-control difference in each parameter taking account of all time points is also presented. Note: numbers incomplete only for WCC; for all other factors, n = 86 for case subjects and 860 for control subjects. DBP, diastolic blood pressure; WCC, white cell count.