Table 1. Baseline characteristics of study participants by quintiles of serum lipoprotein(a) in the EPIC-Norfolk study (n=18,490).
| Q1 (n=3,708) | Q2 (n=3,695) | Q3 (n=3,693) | Q4 (n=3,696) | Q5 (n=3,698) | P-value | |
|---|---|---|---|---|---|---|
| Lp(a) (mg/dL): median (range) | 3.9 (2.0-5.3) | 7.1 (5.3-9.0) | 11.6 (9.0-15.4) | 21.8 (15.4-35.4) | 53.5 (35.4-175.0) | |
| Age (years) | 58.4 (9.1) | 58.6 (9.2) | 59.4 (9.2) | 60.0 (9.0) | 59.5 (9.1) | <0.0001 |
| Women (%)^ | 2018 (54.4) | 2020 (54.7) | 2044 (55.4) | 2061 (55.8) | 2099 (56.8) | 0.3 |
| BMI (kg/m2) | 26.4 (4.0) | 26.1 (3.8) | 26.2 (3.7) | 26.3 (3.7) | 26.2 (3.8) | 0.6 |
| Alcohol (units/week) | 7.5 (9.5) | 7.2 (9.5) | 6.9 (9.3) | 6.6 (8.9) | 6.9 (9.3) | <0.0001 |
| Smoking status | ||||||
| Current smoker (%) | 419 (11.4) | 428 (11.7) | 435 (11.9) | 399 (10.9) | 396 (10.8) | |
| Former smoker (%) | 1536 (41.7) | 1526 (41.7) | 1559 (42.6) | 1542 (42.1) | 1520 (41.4) | |
| Never smoker (%) | 1725 (46.9) | 1708 (46.6) | 1669 (45.6) | 1718 (47.0) | 1756 (47.8) | 0.3 |
| Family history of diabetes (%) | 509 (13.7) | 504 (13.7) | 481 (13.0) | 473 (12.8) | 419 (11.3) | 0.02 |
| Family history of CHD (%) | 1233 (33.3) | 1306 (35.4) | 1320 (35.8) | 1376 (37.3) | 1506 (40.8) | <0.0001 |
| Incident diabetes (%) | 159 (4.3) | 101 (2.7) | 112 (3.0) | 123 (3.3) | 98 (2.7) | <0.0001 |
| Incident CHD (%) | 390 (10.5) | 419 (11.3) | 472 (12.8) | 507 (13.7) | 614 (16.6) | <0.0001 |
| Prevalent diabetes (%) | 123 (3.3) | 116 (3.1) | 118 (3.2) | 102 (2.8) | 121 (3.3) | 0.7 |
| Prevalent cancer (%) | 176 (4.8) | 186 (5.0) | 205 (5.6) | 199 (5.4) | 186 (5.0) | 0.5 |
| Prevalent CHD (%) | 97 (2.6) | 109 (3.0) | 110 (3.0) | 114 (3.1) | 161 (4.4) | <0.0001 |
| Prevalent stroke (%) | 44 (1.2) | 46 (1.3) | 56 (1.5) | 51 (1.4) | 60 (1.6) | 0.5 |
| Lipid parameters | ||||||
| Total cholesterol (mmol/L) | 6.0 (1.1) | 6.0 (1.1) | 6.2 (1.1) | 6.3 (1.2) | 6.5 (1.1) | <0.0001 |
| HDL-cholesterol (mmol/L) | 1.4 (0.4) | 1.4 (0.4) | 1.4 (0.4) | 1.4 (0.4) | 1.5 (0.5) | 0.07 |
| LDL-cholesterol (mmol/L) | 3.7 (1.0) | 3.8 (1.0) | 4.0 (1.0) | 4.1 (1.0) | 4.2 (1.0) | <0.0001 |
| Triglycerides (mmol/L)* | 1.9 (1.8-1.9) | 1.8 (1.7-1.8) | 1.8 (1.7-1.8) | 1.8 (1.7-1.8) | 1.8 (1.7-1.8) | 0.4 |
| antihypertensive medication | 630 (17.0) | 614 (16.6) | 631 (17.1) | 762 (20.6) | 719 (19.4) | <0.0001 |
| Lipid lowering drugs (%) | 40 (1.1) | 36 (1.0) | 54 (1.5) | 61 (1.7) | 70 (1.9) | 0.003 |
| Systolic BP (mm Hg) | 134.5 (17.8) | 134.5 (18.3) | 135.4 (18.6) | 136.4 (18.5) | 134.6 (18.2) | 0.03 |
| Diastolic BP (mm Hg) | 82.1 (11.0) | 82.1 (11.4) | 82.2 (11.3) | 82.8 (11.1) | 81.9 (11.1) | 0.2 |
| Highest education | ||||||
| None or primary school (%) | 1256 (33.9) | 1312 (35.5) | 1387 (37.6) | 1403 (38.0) | 1421 (38.5) | |
| O-level or equivalent (%) | 386 (10.4) | 384 (10.4) | 379 (10.3) | 389 (10.5) | 356 (9.6) | |
| A-level or equivalent (%) | 1559 (42.1) | 1507 (40.8) | 1462 (39.6) | 1439 (39.0) | 1459 (39.5) | |
| Degree or higher (%) | 504 (13.6) | 490 (13.3) | 464 (12.6) | 463 (12.5) | 459 (12.4) | 0.01 |
| Physical activity | ||||||
| Inactive (%) | 1047 (28.2) | 1065 (28.8) | 1146 (31.0) | 1097 (29.7) | 1164 (31.5) | |
| Moderately inactive (%) | 1106 (29.8) | 1113 (30.1) | 995 (26.9) | 1072 (29.0) | 1019 (27.6) | |
| Moderately active (%) | 858 (23.1) | 835 (22.6) | 855 (23.2) | 850 (23.0) | 812 (22.0) | |
| Active (%) | 697 (18.8) | 682 (18.5) | 697 (18.9) | 677 (18.3) | 703 (19.0) | 0.04 |
| CRP (mg/L)* | 2.9 (2.7-3.1) | 2.9 (2.7-3.1) | 3.1 (2.9-3.3) | 3.4 (3.1-3.6) | 3.2 (3.0-3.4) | <0.0001 |
| HbAlc (%) (mmol/mol)‡ | 5.2 (33) | 5.2 (33) | 5.3 (34) | 5.3 (34) | 5.3 (34) | <0.0001 |
Data are either mean (SD) or number (%); IQR: interquartile range
*
Data are geometric mean (95% confidence interval); P-value is the test for proportions for categorical variables or the test for linear trend for continuous variables; BP: blood pressure
^
number is different.
‡
Only 7405 participants have HbAlc data.