Table 2.
Lipoprotein Particle Concentration Versus CHD Risk, by Particle Subclass
| Lipoprotein subclass | Particle concentration, μmol/L | A: adjusted for age and sex only | B: adjusted for age, sex, and other confounders | |||
|---|---|---|---|---|---|---|
| Baseline mean | Usual SD | HR (99% CI) | LR χ2 | HR (99% CI) | LR χ2 | |
| VLDL | ||||||
| Extremely large | 0.002 | 0.001 | 1.18 (1.14–1.22) | 121.4 | 1.11 (1.07–1.16) | 44.2 |
| Very large | 0.003 | 0.002 | 1.23 (1.18–1.28) | 180.7 | 1.16 (1.12–1.21) | 84.5 |
| Large | 0.010 | 0.004 | 1.24 (1.19–1.29) | 189.3 | 1.18 (1.13–1.23) | 95.9 |
| Medium | 0.036 | 0.009 | 1.25 (1.20–1.30) | 184.6 | 1.21 (1.16–1.26) | 126.0 |
| Small | 0.039 | 0.010 | 1.27 (1.22–1.32) | 225.1 | 1.22 (1.17–1.27) | 139.8 |
| Very small | 0.057 | 0.010 | 1.26 (1.21–1.31) | 198.7 | 1.22 (1.17–1.28) | 150.1 |
| All | 0.147 | 0.035 | 1.28 (1.23–1.33) | 230.1 | 1.22 (1.17–1.28) | 148.7 |
| IDL | 0.323 | 0.054 | 1.18 (1.13–1.23) | 97.4 | 1.16 (1.11–1.21) | 82.0 |
| LDL | ||||||
| Large | 0.754 | 0.128 | 1.21 (1.16–1.26) | 139.2 | 1.19 (1.14–1.24) | 119.1 |
| Medium | 0.301 | 0.054 | 1.20 (1.15–1.25) | 125.8 | 1.18 (1.13–1.23) | 94.8 |
| Small | 0.174 | 0.028 | 1.24 (1.19–1.29) | 170.7 | 1.20 (1.15–1.26) | 127.1 |
| All | 1.229 | 0.207 | 1.22 (1.17–1.27) | 148.3 | 1.20 (1.15–1.25) | 120.6 |
| HDL | ||||||
| Very large | 0.243 | 0.082 | 0.85 (0.80–0.89) | 70.7 | 0.94 (0.89–0.99) | 9.2 |
| Large | 1.451 | 0.672 | 0.75 (0.70–0.79) | 201.5 | 0.83 (0.78–0.88) | 71.6 |
| Medium | 3.837 | 0.696 | 0.80 (0.77–0.84) | 136.8 | 0.86 (0.82–0.90) | 62.2 |
| Small | 9.583 | 0.907 | 1.00 (0.95–1.04) | 0.1 | 0.99 (0.95–1.04) | 0.2 |
| All | 15.114 | 1.722 | 0.85 (0.81–0.89) | 80.2 | 0.90 (0.86–0.95) | 31.1 |
HRs per usual SD higher level of particle concentration among 89 422 participants. HRs calculated by Cox proportional hazards models with: (A) stratification by age and sex; and (B) model A with further adjustment for ethnicity, education, region, Townsend Deprivation Index, smoking, alcohol, and body mass index. LR χ2 improvement with the addition of the exposure variable to the model with stated adjustments. “Usual SD” was obtained from the baseline SD through multiplication by square root of the regression dilution ratio, representing an unbiased estimate of the long‐term average level in each baseline‐defined group. CHD indicates coronary heart disease; HDL, high‐density lipoprotein; HR, hazard ratio; IDL, intermediate‐density lipoprotein; LDL, low‐density lipoprotein; LR, likelihood ratio; and VLDL, very‐low‐density lipoprotein.