Table 3

Adjusted regression coefficients of 25(OH)D with components of metabolic syndrome, A1C, fasting insulin, and HOMA-IR

Model 1
Model 2
Model 3
Model 4
β (SEM)Pβ (SEM)Pβ (SEM)Pβ (SEM)P
All (N = 3,262)
    Fasting glucose (mmol/l)−0.17 (0.08)0.0277−0.17 (0.08)0.0337−0.18 (0.08)0.0262−0.17 (0.08)0.0281
    A1C (%)−0.21 (0.05)<0.0001−0.20 (0.05)<0.0001−0.21 (0.05)<0.0001−0.21 (0.05)<0.0001
    Fasting insulin (pmol/l)*−0.08 (0.02)0.0004−0.07 (0.02)0.0036−0.06 (0.02)0.0088−0.06 (0.02)0.0114
    HOMA-IR−0.09 (0.02)0.0002−0.07 (0.02)0.0014−0.07 (0.02)0.0035−0.06 (0.02)0.0044
    Waist circumference (cm)−1.61 (0.46)0.0005−1.64 (0.47)0.0005−1.46 (0.48)0.0023
    Triglycerides (mmol/l)−0.13 (0.03)<0.0001−0.12 (0.03)<0.0001−0.11 (0.03)<0.0001−0.10 (0.03)<0.0001
    HDL cholesterol (mmol/l)§0.07 (0.01)<0.00010.07 (0.02)<0.00010.06 (0.02)<0.00010.06 (0.01)<0.0001
    Diastolic blood pressure (mmHg)−1.29 (0.48)0.0072−1.32 (0.49)0.0074−1.25 (0.50)0.0122−1.15 (0.48)0.0169
    Systolic blood pressure (mmHg)−1.37 (0.95)0.1486−1.52 (0.98)0.1185−1.28 (0.99)0.1964−1.08 (0.95)0.2577
Sex
    Men (n = 1,443)
        Triglycerides (mmol/l)−0.19 (0.04)<0.0001−0.19 (0.04)<0.0001−0.19 (0.04)<0.0001−0.19 (0.04)<0.0001
        HDL cholesterol (mmol/l)0.10 (0.02)<0.00010.10 (0.02)<0.00010.10 (0.02)<0.00010.10 (0.02)<0.0001
    Women (n = 1,819)
        Triglycerides (mmol/l)−0.07 (0.04)0.0574−0.04 (0.04)0.2554−0.03 (0.04)0.4546−0.02 (0.03)0.5907
        HDL cholesterol (mmol/l)0.03 (0.02)0.08410.03 (0.02)0.11820.02 (0.02)0.31210.02 (0.02)0.4327
Obesity status
    BMI <24 kg/m2 (n = 1,526)
        Fasting insulin (pmol/l)−0.04 (0.03)0.2653−0.03 (0.03)0.4596−0.02 (0.04)0.5948
        HOMA-IR−0.03 (0.03)0.2977−0.02 (0.03)0.4530−0.02 (0.03)0.5874
    BMI ≥24 kg/m2 (n = 1,736)
        Fasting insulin (pmol/l)−0.14 (0.03)<0.0001−0.13 (0.03)<0.0001−0.12 (0.03)0.0001
        HOMA-IR−0.15 (0.03)<0.0001−0.13 (0.03)<0.0001−0.13 (0.03)<0.0001
  • 25(OH)D, fasting insulin, HOMA-IR, and triglycerides were log-transformed before analysis. Model 1: adjusted for age, sex (not for sex-stratified analysis), geographic location (Beijing/Shanghai), residential region (urban/rural), and visit date (April or May/June). Model 2: further adjusted for education (≤6, 7–9, or ≥10 years in school), physical activity (low, moderate, or high), smoking (current, former, or never), alcohol drinking (yes/no), family history of CVD (yes/no) and diabetes (yes/no), and self-reported CHD (yes/no) and stroke (yes/no). For fasting glucose, A1C, fasting insulin, and HOMA-IR, hypertension (yes/no) was included in the model. Model 3: further adjusted for inflammatory factors (CRP and IL-6, continuous variables). Model 4: further adjusted for BMI (not for waist circumference and obesity status-stratified analysis).

  • *4 participants were excluded with a missing value of fasting insulin; P for interaction between 25(OH)D and obesity status = 0.0363.

  • †23 participants were excluded with a missing value of HOMA-IR; P for interaction between 25(OH)D and obesity status = 0.0187.

  • P for interaction between 25(OH)D and sex = 0.0034.

  • §P for interaction between 25(OH)D and sex = 0.0027.