Table 1 Characteristics of participants
Variables | Total (n = 7959) | Non-hypothyroidism (n = 7746) | Hypothyroidism (n = 213) | Statistics | P |
|---|---|---|---|---|---|
Age, years, Mean (S.E) | 45.84 (0.37) | 45.71 (0.38) | 50.13 (1.63) | t=-2.63 | 0.012 |
Gender, n (%) | χ2 = 9.057 | 0.003 | |||
Female | 3881 (50.38) | 3755 (50.02) | 126 (62.29) | ||
Male | 4078 (49.62) | 3991 (49.98) | 87 (37.71) | ||
Race, n (%) | χ2 = 32.896 | < 0.001 | |||
Non-Hispanic White | 3668 (69.90) | 3532 (69.49) | 136 (83.57) | ||
Non-Hispanic Black | 1577 (10.33) | 1562 (10.55) | 15 (2.94) | ||
Mexican American | 1320 (8.30) | 1286 (8.36) | 34 (6.31) | ||
Other | 1394 (11.46) | 1366 (11.59) | 28 (7.18) | ||
Education level, n (%) | χ2 = 3.132 | 0.209 | |||
Less Than High School | 2277 (19.02) | 2214 (19.06) | 63 (17.81) | ||
High School or equivalent | 1839 (23.31) | 1795 (23.44) | 44 (18.97) | ||
College or above | 3843 (57.67) | 3737 (57.51) | 106 (63.22) | ||
Marital Status, n (%) | χ2 = 1.354 | 0.245 | |||
Married | 4805 (63.92) | 4670 (63.80) | 135 (67.77) | ||
Unmarried | 3154 (36.08) | 3076 (36.20) | 78 (32.23) | ||
PIR, n (%) | χ2 = 1.632 | 0.201 | |||
≤1.85 | 3642 (32.76) | 3541 (32.88) | 101 (28.76) | ||
>1.85 | 4317 (67.24) | 4205 (67.12) | 112 (71.24) | ||
Smoking, n (%) | χ2 = 1.946 | 0.378 | |||
Never smoke | 4280 (54.08) | 4165 (54.02) | 115 (56.30) | ||
Former smoker | 2026 (24.88) | 1967 (24.81) | 59 (27.16) | ||
Current smoker | 1653 (21.04) | 1614 (21.17) | 39 (16.54) | ||
Drinking, n (%) | χ2 = 0.270 | 0.603 | |||
Non-drinkers | 1110 (10.90) | 1077 (10.94) | 33 (9.80) | ||
Drinkers | 6849 (89.10) | 6669 (89.06) | 180 (90.20) | ||
Six-month time period, n (%) | χ2 = 0.519 | 0.471 | |||
November 1 through April 30 | 3587 (38.96) | 3499 (39.06) | 88 (35.58) | ||
May 1 through October 31 | 4372 (61.04) | 4247 (60.94) | 125 (64.42) | ||
Examination session, n (%) | χ2 = 11.633 | 0.003 | |||
Morning | 3913 (48.96) | 3795 (48.87) | 118 (52.25) | ||
Afternoon | 2813 (33.43) | 2763 (33.80) | 50 (21.30) | ||
Evening | 1233 (17.60) | 1188 (17.34) | 45 (26.45) | ||
Thyroid hormones use, n (%) | χ2 = 52.522 | < 0.001 | |||
No | 7516 (94.02) | 7359 (94.53) | 157 (76.94) | ||
Yes | 443 (5.98) | 387 (5.47) | 56 (23.06) | ||
Thyroid problem, n (%) | χ2 = 52.309 | < 0.001 | |||
No | 7296 (90.79) | 7163 (91.62) | 133 (63.28) | ||
Yes | 663 (9.21) | 583 (8.38) | 80 (36.72) | ||
Autoimmune thyroiditis, n (%) | χ2 = 184.992 | < 0.001 | |||
No | 6839 (85.07) | 6740 (86.41) | 99 (40.24) | ||
Yes | 1120 (14.93) | 1006 (13.59) | 114 (59.76) | ||
BMI, kg/m2, n (%) | χ2 = 1.267 | 0.531 | |||
<25 | 2692 (33.85) | 2620 (33.96) | 72 (30.40) | ||
25-29.9 | 2414 (32.72) | 2357 (32.78) | 57 (30.90) | ||
≥30 | 2853 (33.42) | 2769 (33.26) | 84 (38.70) | ||
Blood cadmium, nmol/L, Mean (S.E) | 4.57 (0.12) | 4.56 (0.12) | 4.79 (0.32) | t=-0.72 | 0.473 |
CDAI, Mean (S.E) | 0.42 (0.13) | 0.44 (0.13) | -0.32 (0.35) | t = 2.33 | 0.024 |
CDAI Level, n (%) | χ2 = 10.067 | 0.007 | |||
<-1.80 | 2987 (33.29) | 2888 (32.92) | 99 (45.80) | ||
-1.80-1.43 | 2672 (33.41) | 2613 (33.60) | 59 (26.99) | ||
≥1.43 | 2300 (33.30) | 2245 (33.48) | 55 (27.21) | ||
Urine Iodine, ug/mg, Mean (S.E) | 5.86 (3.32) | 5.94 (3.41) | 3.24 (0.49) | t = 0.80 | 0.429 |
Energy, kcal, Mean (S.E) | 2188.52 (17.54) | 2194.20 (17.26) | 1999.43 (85.40) | t = 2.33 | 0.024 |
Protein energy ratio, %, Mean (S.E) | 15.54 (0.09) | 15.53 (0.09) | 15.66 (0.42) | t=-0.33 | 0.746 |
Carbo energy ratio, %, Mean (S.E) | 48.98 (0.30) | 49.02 (0.29) | 47.86 (1.12) | t = 1.08 | 0.287 |
Fat energy ratio, %, Mean (S.E) | 33.53 (0.18) | 33.55 (0.18) | 32.89 (0.82) | t = 0.84 | 0.405 |