Table 1.
Sample characteristics and image analysis results.
| All | WMH-Q1 | WMH-Q4 | Statistic | |
|---|---|---|---|---|
| n = 921 | n = 228 | n = 232 | ||
| Age, years (IQR) | 64.0 (14.0) | 56.0 (10.0) | 70.5 (7.0) | t = − 19.21 |
| p < 0.001 | ||||
| Females, n (%) | 419 (45.5) | 112 (49.1) | 106 (45.7) | χ2 = 0.415 |
| p = 1 | ||||
| Brain volume, ml (IQR) | 1457.532 (197.5) | 1474.190 (199.5) | 1445.551 (211.9) | t = 1.52 |
| p = 1 | ||||
| WMH load, % (IQR) | 0.044 (0.101) | 0.007 (0.008) | 0.227 (0.188) | t = − 21.63 |
| p < 0.001 | ||||
| Current smokers, n (%) | 144 (15.6) | 38 (16.7) | 38 (16.4) | χ2 = 0.002 |
| p = 1 | ||||
| Diabetes *, n (%) | 74 (8.0) | 11 (4.8) | 29 (12.5) | χ2 = 6.788 |
| p = 1 | ||||
| Hypertension **, n (%) | 631 (68.5) | 129 (56.6) | 186 (80.2) | χ2 = 23.25 |
| p < 0.001 | ||||
| BMI (IQR) | 25.75 (5.54) | 25.75 (5.54) | 26.69 (5.57) | t = − 0.799 |
| p = 1 | ||||
| Years of education (IQR) | 13 (4) | 14.5 (4) | 13 (3) | t = 5.72 |
| p < 0.001 | ||||
| MMSE (IQR) | 28 (2) | 29 (1) | 28 (2) | t = 3.622 |
| p = 1 | ||||
| TMT-A, seconds (IQR) | 36 (17) | 33 (14) | 42 (18.5) | t = − 6.244 |
| p < 0.001 | ||||
| TMT-B, seconds (IQR) | 79 (37) | 68 (30) | 88 (43) | t = − 6.015 |
| p < 0.001 | ||||
| TMT-delta, seconds (IQR) | 40 (30) | 37 (22) | 45 (34) | t = − 4.195 |
| p < 0.01 |
Displayed p-values were Bonferroni-corrected for multiple comparisons.
WMH White Matter Hyperintensities, WMH-Q1 individuals in the lowest quartile of WMH load, WMH-Q4 individuals in the highest quartile of WMH load, MMSE mini-mental state examination, TMT-A trail making test a, TMT-B trail making test b, TMT-delta difference of TMT-B and TMT-A.
*Presence of diabetes was defined as a blood glucose level > 126 mg/dl or a self-reported prevalence of diabetes.
**Presence of hypertension was defined as blood pressure ≥ 140/90 mm/Hg, hypertensive medication intake or self-reported prevalence of hypertension.