Table 3 Mean creatinine, eGFR and uric acid, by sample characteristics

Overall

1961

0.75

95.7

142.9

301.8

Sex

 Male

1064

0.81

P < 0.001

90.9

P < 0.001

149.7

P < 0.001

333.8

P < 0.001

 Female

897

0.68

101.3

134.9

263.7

Age

 12

233

0.60

110.8

147.5

270.4

P < 0.001

 13

249

0.64

P < 0.001

107.0

P < 0.001

163.3

P < 0.001

283.1

 14

258

0.71

98.9

150.9

301.0

 15

227

0.76

93.8

143.4

311.4

 16

246

0.81

90.5

137.0

309.3

 17

244

0.81

89.0

136.4

314.9

 18

267

0.82

87.8

131.9

311.9

 19

237

0.82

88.2

133.0

310.9

Race/Ethnicity

 Mexican American

589

0.70

Reference

99.9

Reference

147.9

Reference

299.4

Reference

 Other Hispanics

139

0.70

P < 0.876

101.1

P < 0.516

151.0

P < 0.224

305.7

P < 0.354

 Non-Hispanic white

547

0.77

P < 0.001

95.2

P < 0.001

143.5

P < 0.005

314.0

P < 0.001

 Non-Hispanic black

594

0.79

P < 0.001

90.2

P < 0.001

135.2

P < 0.001

292.1

P < 0.073

 Other race

92

0.72

P < 0.499

98.4

P < 0.451

144.6

P < 0.279

300.4

P < 0.899

Poverty to Income Ratio

 First Quartile (<0.78)

423

0.75

Reference

95.5

Reference

141.3

Reference

305.2

Reference

 Second quartile (0.78 to1.45)

449

0.74

P < 0.591

95.4

P < 0.941

141.6

P < 0.837

295.1

P < 0.035

 Third Quartile (>1.46 to 2.92)

468

0.75

P < 0.898

96.1

P < 0.633

144.5

P < 0.079

300.6

P < 0.335

 Fourth Quartile (>2.92)

495

0.75

P < 0.590

95.4

P < 0.930

143.7

P < 0.176

306.2

P < 0.825

 Missing

126

0.75

P < 0.873

96.2

P < 0.705

143.9

P < 0.341

300.8

P < 0.536

Parent/Caregiver Education Level

 Less than 9th grade

263

0.71

Reference

100.3

Reference

147.5

Reference

299.8

Reference

 9-12th grade

372

0.74

P < 0.044

95.4

P < 0.001

142.3

P < 0.019

299.9

P < 0.978

 High school Grad/GED

459

0.77

P < 0.001

93.9

P < 0.001

141.9

P < 0.008

304.2

P < 0.420

 College or AA degree

522

0.76

P < 0.001

94.8

P < 0.001

141.9

P < 0.007

303.1

P < 0.537

 College or greater

259

0.74

P < 0.048

96.3

P < 0.015

142.2

P < 0.028

297.9

P < 0.766

 Unknown

86

0.75

P < 0.076

95.3

P < 0.032

144.9

P < 0.432

306.7

P < 0.428

Serum Cotinine

  < 0.015 ng/mL

312

0.69

Reference

102.2

Reference

148.5

Reference

284.1

Reference

 0.015-1.9 ng/mL

1284

0.74

P < 0.001

96.6

P < 0.001

143.9

P < 0.007

299.0

P < 0.001

  ≥ 2.0 ng/mL

365

0.85

P < 0.001

86.9

P < 0.001

134.8

P < 0.001

326.7

P < 0.001

High Cholesterol

 Total Cholesterol < 170 mg/dL

1312

0.74

P < 0.310

96.1

P < 0.115

144.1

P < 0.005

298.1

P < 0.001

 Total Cholesterol ≥ 170 mg/dL

648

0.75

94.7

140.4

309.0

Obesity Status

 Not Obese

1531

0.75

P < 0.016

94.8

P < 0.001

141.6

P < 0.001

290.9

P < 0.00

 Obese

429

0.73

98.7

147.4

340.3

Insulin Status

 HOMA-IR <4.39

767

0.76

P < 0.009

95.2

P < 0.001

142.4

P < 0.001

295.4

P < 0.001

 HOMA-IR ≥4.39

195

0.71

101.1

150.3

337.4

Blood Pressure Status

 Blood Pressure <90th Percentile

1752

0.75

P < 0.503

95.4

P < 0.353

142.5

P < 0.272

300.2

P < 0.006

 Blood Pressure ≥90th Percentile

151

0.74

96.9

145.0

316.5