Table 1 Descriptive statistics for subjects included in analyses versus those excluded owing to missing data at baseline
| Variable | Baseline 1988 sample, n = 1,189 | Subjects with complete 1988 data, n = 779 | Subjects missing IL-6 data, n = 60 | Subjects missing covariate data, n = 350 | p Value for group differences |
|---|---|---|---|---|---|
| Values are means (SD) or percentages. The p values reflect F tests for continuous variables and χ2 tests for categorical variables for group differences among the second to fourth data columns. Where overall test was significant, groups with the same superscript have significant post hoc differences between them. | |||||
| IL-6 = interleukin-6; HBA1c = hemoglobin A1c. | |||||
| Cognitive scores, 1988 | 52.9 (9.9) | 53.5 (9.8)1 | 52.4 (11.2) | 51.7 (9.8)1 | 0.02 |
| % low | 51.7 | 48.82 | 56.7 | 57.62 | 0.02 |
| IL-6, pg/mL | 4.55 (5.5) | 4.61 (5.6) | — | 4.14 (4.8) | 0.4 |
| % middle tertile | 33.3 | 32.9 | — | 36.6 | — |
| % top tertile | 33.5 | 34.1 | — | 28.7 | 0.5 |
| Age, y | 74.3 (2.7) | 74.3 (2.7) | 73.7 (2.6) | 74.4 (2.7) | 0.2 |
| Men, % | 45 | 473 | 48 | 383 | 0.01 |
| Race, % nonwhite | 19 | 18 | 30 | 19 | 0.07 |
| Education, y | 10.6 (3.3) | 10.7 (3.3) | 10.2 (3.7) | 10.4 (3.2) | 0.2 |
| Av. annual income, $ | 15,411 | 16,226 | 15,008 | 12,875 | 0.001 |
| (12,335) | (12,591)4 | (13,408) | (10,830)4 | — | |
| Body mass index, kg/m2 | 26.0 (4.2) | 26.0 (4.2) | 25.7 (4.3) | 26.1 (4.2) | 0.8 |
| Average HBA1c, % | 6.8 (1.9) | 6.9 (2.0) | 6.3 (1.2) | 6.6 (1.1) | 0.03 |
| Any alcohol last mo, % | 40 | 435 | 33 | 345 | 0.01 |
| Ever smoker, % | 52 | 53 | 52 | 51 | 0.9 |
| Activity score | 20.8 (26.6) | 21.9 (26.7) | 21.7 (26.1) | 18.1 (26.3) | 0.08 |
| Diabetes mellitus, % | 13 | 14 | 8 | 12 | 0.4 |
| Cancer, % | 18 | 19 | 13 | 17 | 0.4 |