Table 1. Baseline characteristics of 12,209 ARIC participants by serum potassium (mEq/L) at baseline.

Characteristics	K < 4.0	4.0 ≤ K < 4.5	4.5 ≤ K < 5.0	5.0 ≤ K ≤ 5.5	p-value*
n	1619	4903	4178	1509
Age	54.0 ± 5.77	53.7 ± 5.65	54.0 ± 5.76	54.0 ± 5.64	0.04
African American race (%)	45.3	25.8	14.2	8.2	<0.01
Female gender (%)	70.0	57.5	50.8	49.0	<0.01
Family history of diabetes (%)	24.0	22.7	22.5	21.3	0.35
BMI (kg/m2)	28.6 ± 5.90	27.4 ± 5.12	26.9 ± 4.70	26.1 ± 4.23	<0.01
Waist circumference (cm)	97.9 ± 14.58	95.9 ± 13.25	95.5 ± 12.84	93.4 ± 12.42	<0.01
Hypertension present (%)	63.6	29.2	22.6	19.7	<0.01
Systolic blood pressure (mmHg)	124 ± 20	119 ± 18	119 ± 17	118 ± 16	<0.01
Serum K+ (mEq/l)	3.68 ± 0.25	4.22 ± 0.14	4.67 ± 0.14	5.17 ± 0.16	<0.01
Serm Mg++ (mEq/l)	1.58 ± 0.17	1.63 ± 0.15	1.66 ± 0.14	1.69 ± 0.14	<0.01
Serum Ca++ (mg/dl)	9.71 ± 0.44	9.70 ± 0.41	9.81 ± 0.41	9.96 ± 0.40	<0.01
Serum Creatinine (mg/dl)	1.06 ± 0.18	1.08 ± 0.18	1.10 ± 0.18	1.12 ± 0.18	<0.01
Fasting glucose (mg/dl)	99.07 ± 10.27	97.81 ± 9.23	98.83 ± 8.93	99.84 ± 8.85	<0.01
Fasting insulin (pmol/l)	95.27 ± 77.87	77.06 ± 56.76	74.70 ± 53.93	67.17 ± 42.48	<0.01
Leisure activity	2.31 ± 0.58	2.38 ± 0.56	2.42 ± 0.56	2.47 ± 0.55	<0.01
Beta-blocker use (%)	16.1	9.0	7.7	8	<0.01
Diuretic use (%)	45.5	13.9	7.9	5.7	<0.01
Ace-inhibitor use (%)	3.2	2.5	2.4	2.1	0.28
Dietary potassium intake (mg/kcal)	1.63 ± 0.43	1.65 ± 0.42	1.68 ± 0.41	1.70 ± 0.41	<0.01
Combine family annual income%					<0.01
>$50,000	15.6	24.3	28.1	34.3
$25,000-$49,999	31.4	37.0	38.6	39.1
$12,000-$24,999	25.5	20.8	19.2	15.0
<$5,000-$11,999	27.4	17.9	14.2	11.6

# values are mean ± standard deviation for continuous variables and % for categorical variables

^*from one-way ANOVA or chi-square test of overall difference

%1986 US dollars