Iodine Intakes of Victorian Schoolchildren Measured Using 24-h Urinary Iodine Excretion
Abstract
:1. Introduction
2. Materials and Methods
2.1. Study Design
2.2. Measures
2.3. Anthropometric Measurements
2.4. 24-h Urine Collection
2.5. Urinalysis
2.6. Validity of Urine Samples
2.7. Statistical Analysis
3. Results
3.1. Demographic Characteristics
3.2. Urinary Parameters, by Gender
3.3. Differences in Urinary Parameters, by Age
3.4. Urinary Parameters, by SES
4. Discussion
5. Conclusions
Acknowledgments
Author Contributions
Conflicts of Interest
References
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All | Boys | Girls | |
---|---|---|---|
Participants, n (%) | 650 | 359 (55) | 291 (45) |
Age (mean (SD), years) | 9.3 (1.8) | 9.3 (1.9) | 9.2 (1.7) |
Age group | |||
4–8 years, n (%) | 280 (43) | 157 (44) | 123 (42) |
9–12 years, n (%) | 370 (57) | 202 (56) | 168 (58) |
SES 1 | |||
Bottom tertile, n (%) | 105 (16) | 45 (13) | 60 (21) a |
Mid tertile, n (%) | 144 (22) | 77 (22) | 67 (23) |
High tertile, n (%) | 401 (62) | 237 (66) a | 164 (56) |
SES 2 | |||
Bottom tertile, n (%) | 134 (24) | 77 (25) | 57 (24) |
Mid tertile, n (%) | 84 (15) | 54 (17) | 30 (12) |
High tertile, n (%) | 336 (61) | 183 (58) | 153 (64) |
BMI category | |||
Underweight, n (%) | 67 (10) | 34 (9) | 33 (11) |
Healthy, n (%) | 473 (73) | 270 (75) | 202 (69) |
Overweight, n (%) | 91 (14) | 45 (13) | 46 (16) |
Obese, n (%) | 20 (3) | 10 (3) | 10 (4) |
Day of urine collection | |||
School day, n (%) | 304 (47) | 168 (47) | 136 (47) |
Non-school day, n (%) | 346 (53) | 191 (53) | 155 (54) |
U-vol (mean (SD), mL/24-h) | 873 (424) | 897 (453) | 843 (384) |
U-Cr (mean (SD), mmol/24-h) | 5.6 (2.0) | 5.8 (2.1) b | 5.3 (1.9) |
UIE (mean (SD), μg/24-h) | 104 (54) | 112 (57) b | 93 (48) |
<EAR *, n (%) | 177 (27) | 77 (21) | 100 (34) a |
>EAR *, n (%) | 473 (73) | 282 (79) a | 191 (66) |
UIC (μg/L) | |||
mean (SD) | 133 (68) | 141 (70) b | 123 (64) |
median (IQR) | 124 (83,172) | 135 (88,180) | 116 (75,161) |
<100 μg/L, n (%) | 233 (36) | 114 (32) | 119 (41) a |
<50 μg/L, n (%) | 49 (8) | 20 (6) | 29 (10) a |
Age Group (Years) | ||
---|---|---|
4–8 (n = 280) | 9–12 (n = 370) | |
U-vol (mL/24-h) | 749 (341) | 966 (456) a |
U-Cr (mmol/24-h) | 4.3 (1.3) | 6.5 (2.0) a |
UIE (μg/24-h) | 94 (48) | 111 (57) a |
<EAR *, n (%) | 80 (29) | 97 (26) |
>EAR *, n (%) | 200 (71) | 273 (74) |
UIC (μg/L) | ||
mean (SD) | 138 (69) | 129 (67) |
median (IQR) | 127 (86,175) | 122.3 (80,170) |
<100 μg/L, n (%) | 89 (32) | 144 (39) |
<50 μg/L, n (%) | 19 (7) | 30 (8) |
SES Category | |||
---|---|---|---|
Bottom Tertile (n = 105) | Mid Tertile (n = 144) | Top Tertile (n = 401) | |
U-vol (mL/24-h) | 868 (478) | 813 (405) | 896 (415) |
U-Cr (mmol/24-h) | 5.7 (2.1) | 5.1 (1.7) | 5.7 (2.1) |
UIE (μg/24-h) | 115 (53) | 100 (47) | 102 (56) |
<EAR *, n (%) | 20 (20) | 38 (26) | 119 (30) |
>EAR *, n (%) | 85 (81) | 106 (74) | 282 (70) |
UIC (μg/L) | |||
mean (SD) | 150 (70) | 139 (72) | 127 (65) |
median (IQR) | 136 (89,195) | 130 (85,175) | 121(78,166) |
<100 μg/L, n (%) | 32 (30%) | 48 (33) | 153 (38) |
<50 μg/L, n (%) | 2 (2%) | 11 (8) | 36 (9) |
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Beckford, K.; Grimes, C.A.; Margerison, C.; Riddell, L.J.; Skeaff, S.A.; Nowson, C.A. Iodine Intakes of Victorian Schoolchildren Measured Using 24-h Urinary Iodine Excretion. Nutrients 2017, 9, 961. https://doi.org/10.3390/nu9090961
Beckford K, Grimes CA, Margerison C, Riddell LJ, Skeaff SA, Nowson CA. Iodine Intakes of Victorian Schoolchildren Measured Using 24-h Urinary Iodine Excretion. Nutrients. 2017; 9(9):961. https://doi.org/10.3390/nu9090961
Chicago/Turabian StyleBeckford, Kelsey, Carley A. Grimes, Claire Margerison, Lynn J. Riddell, Sheila A. Skeaff, and Caryl A. Nowson. 2017. "Iodine Intakes of Victorian Schoolchildren Measured Using 24-h Urinary Iodine Excretion" Nutrients 9, no. 9: 961. https://doi.org/10.3390/nu9090961