Table 1.
Baseline characteristics of study cohorts.
| Characteristic | Study individuals, no. (%) | ||
|---|---|---|---|
| Cohort 1 (n = 5580) | Cohort 2 (n = 6057) | Cohort 3 (n = 7249) | |
| Testing year compared | 2018 vs. 2017 | 2019 vs. 2018 | 2020 vs. 2019 |
| Group 1: individuals whose vitamin D increased by ≥ 10 ng/mLa | 3246 (58.2) | 2820 (46.6) | 4393 (60.6) |
| Group 2: individuals whose vitamin D decreased by ≥ 10 ng/mLa | 2334 (41.8) | 3237 (53.4) | 2856 (39.4) |
| Age, years | |||
| Median (IQR) | 48 (38–56) | 48 (38–56) | 49 (39–57) |
| Sex | |||
| Male | 1674 (30.0) | 1837 (30.3) | 2215 (30.6) |
| Female | 3906 (70.0) | 4220 (69.7) | 5034 (69.4) |
| Race/ethnicity | |||
| Asian | 684 (15.6) | 726 (15.4) | 1209 (17.0) |
| Black | 995 (22.7) | 1094 (23.2) | 1323 (18.6) |
| Hispanic | 539 (12.3) | 643 (13.6) | 801 (11.2) |
| Otherb | 30 (0.7) | 29 (0.6) | 585 (8.2) |
| White | 2128 (48.6) | 2232 (47.2) | 3212 (45.0) |
| Education | |||
| No college degree | 2618 (47.8) | 2818 (47.4) | 3234 (46.4) |
| College degree | 2862 (52.2) | 3128 (52.6) | 3730 (53.6) |
| Body mass index (kg/m2) | |||
| ≥ 30 | 1925 (34.5) | 2154 (35.6) | 2525 (34.9) |
| < 30 | 3653 (65.5) | 3896 (64.4) | 4717 (65.1) |
| Blood pressure | |||
| High | 2417 (43.3) | 2606 (43.1) | 3098 (42.8) |
| Elevated | 817 (14.6) | 938 (15.5) | 1156 (16.0) |
| Normal | 2343 (42.0) | 2505 (41.4) | 2987 (41.3) |
| Smoking | |||
| Yes | 554 (9.9) | 709 (11.7) | 813 (11.2) |
| No | 5025 (90.1) | 5348 (88.3) | 6427 (88.8) |
| Geographical location | |||
| Northeast | 1056 (18.9) | 1151 (19.1) | 1409 (19.5) |
| Midwest | 1020 (18.3) | 1083 (18.0) | 1256 (17.4) |
| West | 1132 (20.3) | 1201 (19.9) | 1504 (20.8) |
| South | 2372 (42.5) | 2593 (43.0) | 3051 (42.3) |
| Vitamin D, ng/mL | |||
| Median (IQR) | 32 (23–44) | 34 (24–46) | 32 (23–42) |
| Lipid levels, mg/dL, median (IQR) | |||
| TC | 184 (160–209) | 183 (161–208) | 184 (161–209) |
| LDL-C | 107 (86–129) | 106 (85–127) | 108 (86–129) |
| HDL-C | 54 (44–66) | 54 (45–66) | 54 (46–65) |
| TG | 97 (69–136) | 94 (68–136) | 95 (69–134) |
IQR: interquartile range; TC: total cholesterol; LDL-C: low-density lipoprotein cholesterol; HDL-C: high-density lipoprotein cholesterol; TG: triglycerides.
aComparisons of baseline characteristics between these two groups are reported in Tables S1, S2 and S3.
bAmerican Indian or Alaska Native, Native Hawaiian or other Pacific Islander, or 2 or more ethnicities.