Table 1.
Population characteristics of US adults aged ≥20 years based on NHANES 1988–1994 and 1999–2002
| Sample with Available SCr | ||
|---|---|---|
| NHANES 1988–1994 (n=15,133) |
NHANES 1999–2002 (n=8,238) |
|
| Age (y)* | 44.6 (0.5) | 46.2 (0.4) |
| Male sex | 47.9 (0.5) | 48.9 (0.4) |
| Race/Ethnicity | ||
| Non-Hispanic white | 76.8 (1.3) | 72.6 (1.8) |
| Non-Hispanic black | 10.4 (0.6) | 10.1 (1.2) |
| Mexican American | 5.1 (0.4) | 7.0 (0.9) |
| Other | 7.8 (0.8) | 10.3 (1.8) |
| Self-reported diabetes* | 3.6 (0.2) | 6.5 (0.3) |
| Hemoglobin A1c ≥ 6.5% | 5.2 (0.3) | 6.1 (0.4) |
| Self-reported hypertension | 23.7 (0.7) | 25.7 (0.9) |
| Systolic blood pressure (mmHg)* | 122.4 (0.4) | 123.7 (0.4) |
| Diastolic blood pressure (mmHg)* | 74.2 (0.2) | 72.5 (0.3) |
| Body Mass Index categories* | 26.6 (0.1) | 28.0 (0.1) |
| <25 kg/m2 | 44.5 (0.9) | 35.1 (0.9) |
| 25-<30 kg/m2 | 33.0 (0.6) | 34.9 (0.8) |
| ≥30 kg/m2 | 22.5 (0.7) | 29.9 (1.0) |
| ACR (mg/g)* | 25.7 (1.6) | 33.7 (3.6) |
| Non-standardized SCr (mg/dl)* | 1.07(0.003) | 0.83 (0.004) |
| Standardized SCr (mg/dl)* | 0.84 (0.003) | 0.90 (0.005) |
| eGFRcr (ml/min/1.73m2)* | 99.0 (0.5) | 93.5 (0.5) |
| Sample with Available SCysC‡ | ||
| NHANES 1988–1994 (n=6,660) |
NHANES 1999–2002 (n=4,343) |
|
| Non-standardized SCr (mg/dl)* | 1.07 (0.005) | 0.82 (0.007) |
| Standardized SCr (mg/dl)* | 0.84 (0.004) | 0.90 (0.007) |
| Non-standardized SCysC (mg/l) | 0.90 (0.01) | 0.89 (0.01) |
| Standardized SCysC (mg/l)* | 0.83 (0.01) | 0.86 (0.01) |
| eGFRcr (ml/min/1.73m2)* | 99.4 (0.8) | 93.6 (0.6) |
| eGFRcys (ml/min/1.73m2)* | 102.9 (0.9) | 99.7 (0.9) |
| eGFRcr-cys (ml/min/1.73m2)* | 102.4 (0.8) | 97.7 (0.7) |
Note: Values for categorical variables are given as percentage (standard error); values for continuous variables are given as weighted mean (standard error). Conversion factor for creatinine in mg/dL to µmol/L, ×88.4.
*
P<0.05 in the comparison between survey periods.
‡
SCysC-based estimates use analytic weights customized for the sampling strategy.
ACR, albumin-creatinine ratio; SCysC, serum cystatin C; NHANES, National Health and Nutrition Examination Survey; eGFR, estimated glomerular filtration rate; eGFRcr, eGFR based on SCr; eGFRcys, eGFR based on SCysC; eGFRcr-cys, eGFR based on SCr and SCysC; SCr, serum creatinine.