Table 2.
Baseline Characteristics According to Quartiles of Cystatin-C in the Control Group*
| Quartile of serum cystatin-C |
p-value | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| 1 | 2 | 3 | 4 | ||||||
| N | % Mean ± SD | N | % Mean ± SD | N | % Mean ± SD | N | % Mean ± SD | ||
| Ethnicity | |||||||||
| White | 97 | 93.3 | 90 | 91.8 | 92 | 95.8 | 98 | 99.0 | 0.008 |
| Black | 0 | 0.0 | 5 | 5.1 | 4 | 4.2 | 1 | 1.0 | |
| Hispanic | 1 | 1.0 | 1 | 1.0 | 0 | 0.0 | 0 | 0.0 | |
| American Indian | 3 | 2.9 | 0 | 0.0 | 0 | 0.0 | 0 | 0.0 | |
| Asian/Pacific Islander | 3 | 2.9 | 2 | 2.0 | 0 | 0.0 | 0 | 0.0 | |
| Age group at screening, years | |||||||||
| 50–59 | 12 | 11.5 | 7 | 7.1 | 4 | 4.2 | 2 | 2.0 | <.001 |
| 60–69 | 46 | 44.2 | 22 | 22.5 | 21 | 21.9 | 16 | 16.2 | |
| 70–79 | 46 | 44.2 | 69 | 70.4 | 71 | 74.0 | 81 | 81.8 | |
| Body mass index (BMI), kg/m2 | |||||||||
| 18.5 – <25 | 53 | 51.5 | 43 | 43.9 | 29 | 30.2 | 19 | 19.2 | <.001 |
| 25 – <30 | 33 | 32.0 | 38 | 38.8 | 36 | 37.5 | 42 | 42.4 | |
| >=30 | 17 | 16.5 | 17 | 17.4 | 31 | 32.3 | 38 | 38.4 | |
| Parents broke hip | 16 | 15.4 | 18 | 18.4 | 14 | 14.6 | 15 | 15.2 | 0.89 |
| HRT usage status | |||||||||
| Never used | 81 | 77.9 | 71 | 72.5 | 72 | 75.0 | 76 | 76.8 | 0.82 |
| Past user | 23 | 22.1 | 27 | 27.6 | 24 | 25.0 | 23 | 23.2 | |
| Oral daily corticosteroid use | 0 | 0.0 | 0 | 0.0 | 2 | 2.1 | 1 | 1.0 | 0.28 |
| General health (self report) | |||||||||
| Excellent/Very good | 62 | 60.8 | 57 | 59.4 | 54 | 56.8 | 46 | 47.4 | 0.41 |
| Good | 28 | 27.5 | 32 | 33.3 | 30 | 31.6 | 40 | 41.2 | |
| Fair/Poor | 12 | 11.8 | 7 | 7.3 | 11 | 11.6 | 11 | 11.3 | |
| Treated diabetes (pills or shots) | 5 | 4.8 | 4 | 4.1 | 4 | 4.2 | 5 | 5.1 | 0.99 |
| Alcohol use | |||||||||
| Non drinker | 11 | 10.7 | 21 | 21.4 | 17 | 17.7 | 20 | 20.6 | 0.01 |
| Past drinker | 19 | 18.5 | 13 | 13.3 | 26 | 27.1 | 20 | 20.6 | |
| <7 drinks per week | 53 | 51.5 | 52 | 53.1 | 48 | 50.0 | 52 | 53.6 | |
| >=7 drinks per week | 20 | 19.4 | 12 | 12.2 | 5 | 5.2 | 5 | 5.2 | |
| RAND 36 physical functioning >90 | 48 | 47.1 | 33 | 34.4 | 21 | 22.8 | 15 | 15.6 | <.001 |
| Thiazides & Thiazide-like | |||||||||
| Diuretic Use | 3 | 2.9 | 5 | 5.1 | 7 | 7.3 | 8 | 8.1 | 0.39 |
| Smoking | |||||||||
| Never smoked | 55 | 53.4 | 47 | 48.0 | 52 | 55.3 | 59 | 60.2 | 0.75 |
| Past smoker | 46 | 44.7 | 48 | 49.0 | 39 | 41.5 | 37 | 37.8 | |
| Current smoker | 2 | 1.9 | 3 | 3.1 | 3 | 3.2 | 2 | 2.0 | |
| Total Energy Expenditure from | 10 | 17.5 ± | 13.2 ± | 12.5 ± | 12.2 ± | ||||
| Physical Activity | 1 | 18.7 | 97 | 13.1 | 94 | 12.5 | 97 | 15.7 | 0.05 |
*
Quartiles defined based on the distribution of cystatin-C levels in the control group. Cases are omitted from the table. P values from Chi-square tests or Fisher exact test.