Table 1.

Sample Population Characteristics (n = 10256)

	Mean or Percent	Standard Error	95% CI
Age (y)	49.59	1.30	46.97–52.20
Gender (% male)	47.07	0.71	45.64–48.51
Race/ethnicity (%)
Non-Hispanic white	77.27	2.28	72.69–81.85
Non-Hispanic black	10.05	1.13	7.79–12.32
Mexican-American	4.76	0.77	3.21–6.31
Other	7.92	1.45	4.99–10.84
Poverty-income ratio	3.17	0.10	2.97–3.37
Highest grade completed	12.23	0.14	11.93–12.52
Self-reported health status (%)
Excellent	18.64	0.96	16.70–20.58
Very good	30.48	1.12	28.23–32.73
Good	33.43	0.81	31.80–36.05
Fair	14.03	1.01	12.01–16.05
Poor	3.37	0.30	2.76–3.97
eGFR (mL/min)	106.21	1.19	103.82–108.60
Chronic kidney disease (%)
Stage 1/2	9.66	0.65	8.36–10.97
Stage 3A	1.80	0.21	1.39–2.22
Stage 3B-5	1.10	0.14	0.83–1.38
Diabetes (%)	13.01	0.85	11.30–14.71
Cancer (%)	4.75	0.45	3.85–5.65
COPD (%)	8.29	0.44	7.41–9.18
Liver disease (%)	8.96	0.64	7.67–10.25
Arthritis (%)	22.84	1.50	19.83–25.85
25 hydroxy vitamin D concentration, serum (ng/mL)	29.38	0.55	28.27–30.49
Hemoglobin (g/dL)	14.20	0.04	14.11–14.28
Bicarbonate, serum (mmol/L)	27.62	0.24	27.15–28.10
C-reactive protein, serum (units)	0.44	0.01	0.41–0.46
Hypertensiona (%)	35.06	1.97	31.11–39.01
Overt cardiovascular diseaseb (%)	12.65	0.92	10.80–14.51

CI = confidence interval; eGFR = estimated glomerular filtration rate; COPD = chronic obstructive pulmonary disease.

^aJoint National Committee 7 guidelines.

^bComposite measure of peripheral arterial disease, coronary artery disease, congestive heart failure, and history of cerebrovascular accident.