Table 1 Characteristics of the study population, National Health and Nutrition Examination Survey (NHANES) 2011–2014 (N = 631)

Number of subjects (%)

502

129

477

154

483

148

Age (%)^a

<0.01

<0.01

0.031

60–70 years

275 (54.78)

57 (44.19)

267 (55.97)

65 (42.21)

268 (55.49)

64 (43.24)

70–80 years

169 (33.67)

38 (39.46)

152 (31.87)

55 (35.71)

150 (31.06)

57 (38.51)

≥80 years

58 (11.55)

34 (26.35)

58 (12.16)

34 (22.08)

65 (13.46)

27 (18.24)

Sex (%)^a

<0.01

0.992

0.0198

Male

261 (51.99)

85 (65.89)

261 (54.72)

85 (55.19)

252 (52.17)

94 (63.51)

Female

241 (48.01)

44 (34.11)

216 (45.28)

69 (44.81)

231 (47.83)

54 (36.49)

Race (%)^a

0.106

<0.01

<0.01

Mexican American

30 (5.98)

14 (10.85)

29 (6.08)

15 (9.74)

19 (3.93)

25 (16.89)

Other Hispanic

47 (9.36)

19 (14.73)

53 (11.11)

13 (8.44)

39 (8.07)

27 (18.24)

Non-Hispanic White

242 (48.21)

55 (42.64)

241 (50.52)

56 (36.36)

252 (52.17)

45 (30.41)

Non-Hispanic Black

138 (27.49)

31 (24.03)

114 (23.90)

55 (35.71)

123 (25.47)

46 (31.08)

Other race

45 (8.96)

10 (7.75)

40 (8.39)

15 (9.74)

50 (10.35)

5 (3.38)

Educational level (%)^a

<0.01

<0.01

<0.01

Below high school

109 (21.71)

53 (41.09)

107 (22.43)

55 (35.71)

78 (16.15)

84 (56.76)

High school

113 (22.51)

27 (20.93)

93 (19.50)

47 (30.52)

110 (22.77)

30 (20.27)

Above high school

280 (55.78)

49 (37.98)

277 (58.07)

52 (33.77)

295 (61.08)

34 (22.97)

Marital status (%)^a

0.99

0.218

0.035

Married/living with partner

293 (58.37)

76 (58.91)

286 (59.96)

83 (53.90)

294 (60.87)

75 (50.68)

Widowed/divorced/separated/never married

209 (41.63)

53 (41.09)

191 (40.04)

71 (46.10)

189 (39.13)

73 (49.32)

Poverty–income ratio (%)^a

0.268

<0.01

<0.01

≤0.99

89 (17.73)

29 (22.48)

76 (15.93)

42 (27.27)

67 (13.87)

51 (34.46)

≥1

413 (82.27)

100 (77.52)

401 (84.07)

112 (72.73)

416 (86.13)

97 (65.54)

Body mass index (%)^a

0.258

0.73

0.538

< 25 kg/m²

117 (23.31)

32 (24.81)

109 (22.85)

40 (25.97)

119 (24.64)

30 (20.27)

25–30 kg/m²

179 (35.66)

54 (41.86)

178 (37.32)

55 (35.71)

175 (36.23)

58 (39.19)

≥ 30 kg/m²

206 (41.04)

43 (33.33)

190 (39.83)

59 (38.31)

189 (39.13)

60 (40.54)

Smoking status (%)^a

0.559

0.376

0.011

Never

237 (47.21)

64 (49.61)

224 (46.96)

77 (50.00)

235 (48.65)

66 (44.59)

Former

210 (41.83)

55 (42.64)

207 (43.40)

58 (37.66)

208 (43.06)

57 (38.51)

Current

55 (10.96)

10 (7.75)

46 (9.64)

19 (12.34)

40 (8.28)

25 (16.89)

drinking status (%)^a

<12drinks/year

349 (70.51)

81 (65.32)

0.312

336 (71.79)

94 (62.25)

0.034

335 (70.38)

95 (66.43)

0.427

≥12drinks/year

146 (29.49)

43 (34.68)

132 (28.21)

57 (37.75)

141 (29.62)

48 (33.57)

Hypertension (%)^a

316 (62.94)

84 (65.12)

0.724

283 (59.33)

117 (75.97)

<0.01

303 (62.73)

97 (65.54)

0.601

Diabetes (%)^a

114 (22.71)

34 (26.37)

0.45

96 (20.13)

52 (33.77)

<0.01

100 (20.7)

48 (32.43)

<0.01

Renal failure (%)^a

33 (6.57)

11 (8.53)

0.56

30 (6.29)

14 (9.09)

0.315

24 (4.97)

20 (13.51)

<0.01

difficulty in thinking (%)^a

65 (12.95)

36 (27.91)

<0.01

65 (13.63)

36 (23.38)

<0.01

68 (14.08)

33 (22.3)

0.024

Arthritis (%)^a

265 (52.79)

59 (45.74)

0.183

245 (51.36)

79 (51.29)

0.99

257 (53.21)

67 (45.27)

0.11

Coronary heart disease (%)^a

34 (6.77)

20 (15.5)

<0.01

34 (7.13)

20 (12.99)

0.036

38 (7.87)

16 (10.81)

0.34

Chronic bronchitis (%)^a

40 (7.97)

9 (6.98)

0.849

42 (8.81)

7 (4.55)

0.123

39 (8.07)

10 (6.76)

0.727

U-Sb concentration