Table 1.
Descriptive statistics of the overall cohort, as well as for each group of coffee consumption.
| Characteristics | Coffee Consumption | p-Value * | |||||
|---|---|---|---|---|---|---|---|
| Overall Cohort | <1 c/d | 1–2 c/d | 3–4 c/d | 5–6 c/d | >6 c/d | ||
| Group size | 2316 | 459 | 1020 | 581 | 176 | 80 | |
| Sociodemographic characteristics | |||||||
| Age, median (IQR) | 65 (14) | 67 (13) | 67 (13) | 62 (14) | 61 (13) | 60 (9) | <0.001 |
| Female sex, n (%) | 1026 (44.3) |
191 (41.61) | 501 (49.12) |
254 (43.72) |
55 (31.25) |
25 (31.25) |
<0.001 |
| Education 1 | <0.001 | ||||||
| Low, n (%) | 98 (4.23) |
25 (5.75) |
47 (4.78) |
18 (3.2) |
6 (3.49) |
2 (2.53) |
|
| Medium, n (%) | 1087 (46.93) |
219 (50.34) |
472 (47.97) |
275 (48.85) |
80 (46.51) |
41 (51.9) |
|
| High, n (%) | 1048 (45.25) |
191 (43.91) |
465 (47.26) |
270 (47.96) |
86 (50) |
36 (45.57) |
|
| Cardiovascular risk factors | |||||||
| Smoking, n (%) | 320 (13.82) |
37 (9.3) |
113 (12.58) |
110 (21.07) |
39 (24.68) |
21 (28.77) |
<0.001 |
| Diabetes mellitus, n (%) 2 | 210 (9.07) |
61 (13.96) |
88 (9.23) |
45 (8.43) |
12 (7.14) |
4 (5.33) |
0.01 |
| Hypertension, n (%) 3 | 1611 (69.56) |
330 (73.99) |
734 (74.37) |
380 (68.1) |
121 (69.94) |
46 (61.33) |
0.015 |
| BMI, median (IQR) | 26.15 (9.45) |
26.18 (5.59) | 25.96 (5.44) |
26.11 (5.43) |
26.49 (4.59) |
28 (4.9) |
0.02 |
| Alcohol consumption [monthly frequency], median (IQR) | 3 (9) |
3 (9) | 3 (7) | 10 (13) | 10 (14) | 3 (9) | 0.001 |
| Adherence to the Mediterranean diet, median (IQR) | 4 (3) | 4 (3) | 4 (3) | 4 (3) | 5 (3) | 4 (2) | 0.945 |
| MRI parameters | |||||||
| Brain volume [mL], median (IQR) | 1210.3 (166.6) |
1204.38 (157.79) |
1195.82 (168.59) |
1226.89 (162.09) |
1238.15 (162.73) |
1240.43 (150.83) |
<0.001 |
| Mean cortical thickness [mm], median (IQR) | 2.61 (0.13) |
2.6 (0.13) |
2.61 (0.13) |
2.62 (0.13) |
2.61 (0.11) |
2.62 (0.11) |
<0.001 |
| WMH volume [mL], median (IQR) | 1.48 (2.22) |
1.61 (2.18) | 1.59 (2.51) |
1.29 (2.09) |
1.32 (1.93) |
1.28 (1.71) |
0.002 |
| PSMD [×105], median (IQR) | 22.3 (4.31) |
22.77 (4.61) | 22.52 (4.36) |
21.96 (4.05) |
22.24 (4.37) |
21.44 (2.81) | <0.001 |
All demographic variables were tested for significant difference between groups of coffee consumption. p-Values < 0.05 were interpreted as significant and are indicated in bold. * Pearson Chi-square test applied for categorical variables; Kruskal–Wallis test applied for continuous variables. 1 Educational level as defined by the International Standard Classification of Education (ISCED). 2 Prevalence of diabetes mellitus was determined based on fasting serum glucose level (>126 mg/dL), non-fasting serum glucose level (>200 mg/dL), or self-report. 3 Prevalence of hypertension was determined based on blood pressure (≥140/90 mmHg), intake of antihypertensive medication, or self-report. Abbreviations: BMI = body mass index, c/d = cups per day, IQR = interquartile range, mL = milliliter, mm = millimeter, MRI = magnetic resonance imaging, PSMD = peak width of skeletonized mean diffusivity, WMH = white matter hyperintensities.