Association between Sensitivity to Thyroid Hormone Indices and Bone Mineral Density in US Males
Table 1
Baseline characteristics of the research population based on lumbar spine BMD quartiles.
Characteristics
Quartiles of lumbar spine BMD
value
Q1 ≤ 0.93
0.93 < Q2 ≤ 1.03
1.03 < Q3 ≤ 1.13
Q4 > 1.13
Demographics
Age (years)
33.81 ± 21.11
38.74 ± 18.64
39.98 ± 18.20
44.47 ± 19.05
<0.001
Race/ethnicity (%)
<0.001
Non-Hispanic white
203 (27.92)
174 (23.61)
148 (18.81)
110 (12.85)
Non-Hispanic black
298 (40.99)
314 (42.61)
363 (46.13)
384 (44.86)
Mexican American
87 (11.97)
111 (15.06)
157 (19.95)
242 (28.27)
Other race
139 (19.12)
138 (18.73)
119 (15.12)
120 (14.02)
Level of education (%)
<0.001
Less than 9th grade
65 (8.94)
87 (11.81)
75 (9.53)
65 (7.59)
9–11th grade
70 (9.63)
116 (15.74)
119 (15.12)
114 (13.318)
High school grad
119 (16.37)
140 (19.00)
156 (19.82)
210 (24.53)
Some college
89 (12.242)
132 (17.91)
161 (20.46)
213 (24.88)
College graduate or above
67 (9.22)
103 (13.98)
141 (17.92)
167 (19.51)
Missing
317 (43.60)
159 (21.57)
135 (17.15)
87 (10.16)
Alcohol consumption (%)
<0.001
Nonsignificant alcohol intake
309 (42.50)
466 (63.23)
535 (67.98)
627 (73.25)
Significant alcohol intake
418 (57.49)
271 (36.97)
252 (32.02)
229 (26.75)
Smoking behavior (%)
<0.001
Significant smoking behavior
231 (31.77)
339 (46.00)
341 (43.33)
403 (47.08)
Never or nonsignificant smoking
496 (68.23)
398 (54.00)
446 (56.67)
453 (52.92)
Physical activity (%)
0.156
Light
112 (15.41)
138 (18.73)
139 (17.662)
166 (19.39)
Moderate
145 (19.95)
112 (15.20)
157 (19.95)
159 (18.58)
High
49 (6.74)
41 (5.56)
53 (6.74)
53 (6.19)
Not recorded
421 (57.91)
446 (60.52)
438 (55.65)
478 (55.84)
BMI (kg/m2)
24.29 ± 5.14
26.49 ± 5.16
27.60 ± 5.06
28.86 ± 4.92
<0.001
Hypertension (%)
103 (14.17)
137 (18.59)
188 (23.89)
273 (31.89)
<0.001
Diabetes (%)
42 (5.78)
53 (7.19)
57 (7.24)
86 (10.05)
0.035
Laboratory indices
HbA1c (%)
5.49 ± 0.94
5.60 ± 1.07
5.60 ± 0.98
5.69 ± 1.01
<0.001
Albumin (g/dL)
4.41 ± 0.31
4.41 ± 0.30
4.39 ± 0.31
4.35 ± 0.3
0.002
Blood urea nitrogen (mg/dL)
11.98 ± 4.12
12.57 ± 4.42
12.93 ± 4.59
13.48 ± 5.34
<0.001
Total calcium (mg/dL)
9.52 ± 0.36
9.49 ± 0.36
9.50 ± 0.36
9.41 ± 0.36
<0.001
Total cholesterol (mg/dL)
191.32 ± 45.17
192.15 ± 40.66
189.81 ± 40.15
190.53 ± 38.90
0.243
Triglycerides (mg/dL)
149.03 ± 145.31
163.37 ± 166.56
160.98 ± 125.17
168.62 ± 153.68
<0.001
Creatinine (mg/dL)
0.82 ± 0.22
0.94 ± 0.36
0.95 ± 0.20
1.02 ± 0.41
<0.001
Phosphorus (mg/dL)
4.20 ± 0.83
3.78 ± 0.64
3.74 ± 0.61
3.74 ± 0.59
<0.001
Uric acid (mg/dL)
5.61 ± 1.21
5.93 ± 1.25
6.06 ± 1.26
6.19 ± 1.30
<0.001
Thyroid parameters
FT3 (pmol/L)
5.51 ± 0.81
5.26 ± 0.64
5.16 ± 0.62
5.04 ± 0.61
<0.001
FT4 (pmol/L)
10.25 ± 1.72
10.23 ± 1.87
10.04 ± 1.76
10.03 ± 1.86
0.006
TSH (mIU/L)
1.96 ± 3.19
1.77 ± 1.39
1.76 ± 1.27
1.93 ± 2.42
0.202
FT3/FT4
0.55 ± 0.12
0.53 ± 0.10
0.53 ± 0.09
0.52 ± 0.10
<0.001
TSHI
1.81 ± 0.66
1.75 ± 0.63
1.72 ± 0.65
1.76 ± 0.67
0.124
TT4RI
19.18 ± 16.67
17.80 ± 13.72
17.36 ± 11.42
18.35 ± 13.98
0.131
TFQI
0.01 ± 0.33
−0.02 ± 0.32
−0.04 ± 0.33
−0.05 ± 0.33
<0.001
Mean ± SD for continuous variables: the value was calculated by the weighted linear regression model. (%) for categorical variables: the value was calculated by the weighted chi-square test. BMD, bone mineral density; BMI, body mass index; HbA1c, glycosylated hemoglobin A1c; FT3, serum free triiodothyronine; FT4, free thyroxine; TSH, thyroid-stimulating hormone; FT3/FT4, free triiodothyronine/free thyroxine; TSHI, thyroid-stimulating hormone index; TT4RI, thyrotroph thyroxine resistance index; TFQI, thyroid feedback quantile-based index.
