Table 1.

Characteristics overall and by age group, US population (NHANES III 1988–1994)

CharacteristicAge Group (yr)Overall
12–19 (n=719)20–39 (n=1675)40–59 (n=1149)≥60 (n=4053)All (n=7596)
Male50.8±3.549.3±2.148.7±2.542.8±0.848.1±1.4
Race/ethnicity
 Non-Hispanic white69.4±3.671.7±2.778.6±2.384.0±1.575.6±2.0
 Non-Hispanic black15.5±2.112.6±1.410.4±1.18.3±0.811.6±1.0
 Mexican American8.3±1.07.0±0.94.3±0.62.3±0.25.5±0.5
 Other ethnicity6.8±1.98.8±1.66.8±1.65.4±1.07.3±1.2
Education <12 yraNA18.6±1.720.1±2.240.0±1.723.0±1.4
Current smokinga10.7±2.236.4±2.227.5±2.214.8±1.026.2±1.1
Obesity (BMI ≥30 kg/m2)a7.1±1.918.0±1.828.3±2.123.8±0.920.4±1.1
Hypertensiona0.6±0.45.2±0.724.0±2.258.7±1.020.1±1.2
Diabetes a0.1±0.11.0±0.36.5±1.112.6±0.74.6±0.5
Low HDL cholesterol (<40 mg/dl for men; <50 mg/dl for women)a38.7±3.236.2±1.739.4±2.137.4±1.437.6±1.3
Triglycerides (mg/dl)a83.799.6130.1143.3112.1
C-reactive protein (mg/dl)a
 <0.2288.9±2.477.4±1.968.7±2.661.4±2.173.5±1.5
 0.22–18.5±1.917.3±1.523.6±2.228.6±1.720.0±1.2
 >12.6±1.34.5±0.77.6±1.59.9±0.76.1±0.6
Albumin/creatinine ratio (mg/g)a,b8.24.76.211.16.6
Estimated GFR, creatinine (ml/min per 1.73 m2)135.6±0.94113.1±0.7796.9±0.6374.5±0.42104.4±0.69
Creatinine (mg/dl)c
 Male0.77±0.010.92±0.010.93±0.011.06±0.010.92±0.01d
 Female0.66±0.010.70±0.010.74±0.010.84±0.010.74±0.005d
Cystatin C (mg/L)c
 Male0.82±0.010.78±0.010.83±0.011.04±0.010.85±0.01d
 Female0.74±0.010.72±0.010.78±0.011.02±0.010.80±0.01d
β-trace protein (mg/L)c
 Male0.60±0.010.54±0.010.56±0.010.77±0.010.59±0.01d
 Female0.56±0.010.51±0.010.54±0.010.72±0.010.57±0.01d
β2-microglobulin (mg/L)c
 Male1.65±0.021.71±0.021.86±0.022.56±0.031.89±0.02e
 Female1.54±0.021.62±0.021.85±0.042.60±0.041.88±0.02e
  • Data are presented as mean ± SEM for continuous data and as a proportion ± SEM for categorical variables. A geometric mean (without SEM) is provided for albumin/creatinine ratio and triglycerides. SEMs for geometric means were not obtained because of complex survey design. Survey sample size is denoted by n. Creatinine may be converted from mg/dl to μmol/L by multiplying by 88.4. Triglycerides may be converted from mg/dl to mmol/L by multiplying by 0.0113. HDL may be converted from mg/dl to mmol/L by multiplying by 0.0259. NHANES III, Third National Health and Nutrition Examination Survey; BMI, body mass index; NA, not available.

  • a Data from a small fraction of participants with unknown covariate distribution not shown.

  • b Albumin/creatinine ratio was determined in a subset of participants that excluded pregnant or menstruating women (n=250).

  • c Men (n=3611), women (n=3985).

  • d P value for overall mean across sexes was <0.01.

  • e P value for overall mean across sexes was 0.66.