Table 3. Hazard Ratios and 95% Confidence Intervals for Incident Metabolic Syndrome according to Baseline Bilirubin Level as a Continuous Variable, and Baseline Bilirubin Quartile (Q1-Q4) in Women (n = 4723).
| Quartiles of baseline bilirubin | Continuous variable HR (95% CI) per 1 standard deviationa | P-value | |||||
|---|---|---|---|---|---|---|---|
| Q1 (n = 980) | Q2 (n = 1532) | Q3 (n = 1127) | Q4 (n = 1084) | P for trend | |||
| 3.4−8.6 μmol/l | 10.3−12.0 μmol/l | 13.7−15.4 μmol/l | 17.1−34.2 μmol/l | ||||
| (0.2−0.5 mg/dl) | (0.6−0.7 mg/dl) | (0.8−0.9 mg/dl) | (1.0−2.0 mg/dl) | ||||
| Mean baseline bilirubin (μmol/l) | 7.7±1.2 | 11.1±0.9 | 14.4±0.8 | 20.6±4.0 | |||
| Incidence of MetS | 208/980 (21.2%) | 235/755 (15.3%) | 153/1127 (13.6%) | 148/1084 (13.7%) | < 0.001 | ||
| Model 1 | 1(ref.) | 0.744 (0.617–0.897) | 0.740 (0.600–0.913) | 0.776 (0.628–0.960) | 0.023 | 0.936 (0.867–1.011) | 0.092 |
| Model 2 | 1(ref.) | 0.722 (0.599–0.871) | 0.714 (0.579–0.882) | 0.715 (0.577–0.886) | 0.003 | 0.908 (0.840–0.982) | 0.016 |
| Model 3 | 1(ref.) | 0.769 (0.637–0.928) | 0.730 (0.591–0.902) | 0.767 (0.619–0.951) | 0.013 | 0.929 (0.859–1.004) | 0.063 |
| Model 4 | 1(ref.) | 0.782 (0.633–0.965) | 0.778 (0.617–0.981) | 0.746 (0.584–0.952) | 0.022 | 0.908 (0.831–0.992) | 0.032 |
| Model 5 | 1(ref.) | 0.761 (0.570–1.016) | 0.983 (0.725–1.334) | 0.915 (0.671–1.248) | 0.911 | 1.023 (0.922–1.136) | 0.667 |
Model 1: adjusted for age, smoking status, and medication (statin and aspirin)
Model 2: adjusted for age, smoking status, medication (statin and aspirin), ALT, uric acid, eGFR, fasting glucose, and baseline diabetes mellitus prevalence
Model 3: adjusted for age, smoking status, medication (statin and aspirin), ALT, uric acid, eGFR, fasting glucose, baseline diabetes mellitus prevalence, systolic BP, waist circumference, and BMI
Model 4: adjusted for age, smoking status, medication (statin and aspirin), ALT, uric acid, eGFR, fasting glucose, baseline diabetes mellitus prevalence, systolic BP, waist circumference, BMI, and alcohol history (n = 3936)
Model 5: adjusted for age, smoking status, medication (statin and aspirin), ALT, uric acid, eGFR, baseline diabetes mellitus prevalence, systolic BP, waist circumference, BMI, and HOMA2-IR (n = 2368)
Abbreviations: HR, hazard ratio; CI, confidence interval; MetS, metabolic syndrome; ALT, alanine aminotransferase; eGFR, estimated glomerular filtration rate; BP, blood pressure; BMI, body mass index; HOMA2-IR, homeostasis model assessment index 2 for insulin resistance.
a 1 standard deviation = 5.02 μmol/l