Table 1: Characteristics of the study population from NHANES 2003–2008a.

CharacteristicsTertile 1 ( )Tertile 2 ( )Tertile 3 ( )P value

Age (years)48.29 ± 0.7445.24 ± 0.7342.26 ± 0.64<0.0001
Female (%)381 (56.3)338 (48.4)343 (48.4)0.03
Race/ethnicity (%)
 Non-Hispanic Whites367 (75.3)357 (71.8)314 (67.5)0.02
 Non-Whites328 (24.7)347 (28.2)391 (32.4)
Smoking status (%)
 Never smoker351 (50.8)338 (49.9)309 (44.5)0.05
 Former smoker186 (26.8)177 (24.5)147 (23.8)
 Current smoker121 (20.2)141 (22.5)161 (26.4)
 Missing37 (2.3)48 (3.1)88 (5.2)
Alcohol intake (%)
 Nondrinker291 (31.8)272 (33.1)312 (35.4)<0.0001
 Moderate drinker278 (49.7)249 (39.7)221 (36.2)
 Heavy drinker126 (18.4)183 (27.2)172 (28.4)
Annual household income
 <$20,000129 (10.8)133 (12.7)160 (15.7)0.02
 $20,000–$54,999261 (32.4)269 (35.9)287 (38.8)
 ≥55,000257 (51.8)250 (45.2)224 (40.9)
 Missing48 (4.9)52 (6.2)34 (4.6)
Moderate physical activity (%)233 (42.4)251 (40.1)265 (39.9)0.69
Waist circumference (cm)95.97 ± 0.7497.81 ± 0.8597.86 ± 0.89<0.0001
Systolic blood pressure (mm of Hg)120.56 ± 0.76120.76 ± 0.60119.58 ± 0.81<0.0001
Diastolic blood pressure (mm of Hg)70.17 ± 0.6669.65 ± 0.5769.48 ± 0.54<0.0001
Serum triglycerides (mg/dL)129.61 ± 3.84138.16 ± 5.88145.81 ± 5.32<0.0001
Serum HDL (mg/dL)57.19 ± 0.8654.86 ± 0.8152.20 ± 0.65<0.0001
Serum glucose (mg/dL)102.78 ± 1.22102.64 ± 1.02104.85 ± 1.58<0.0001
Urinary creatinine (mg/dL)85.03 ± 2.57132.83 ± 3.07175.80 ± 4.14<0.0001
Metabolic Syndrome (%)30.034.938.90.01

aData presented are number (percentages) or mean values ± standard error (SE), as appropriate for the variable.