Plasma 25-Hydroxy Vitamin D Is Not Associated with Either Cognitive Function or Academic Performance in Adolescents
Abstract
1. Introduction
2. Methods
2.1. Cognitive Function Tests and Students’ Academic Performance
2.2. Blood Collection and Biochemical Analyses
2.3. Statistical Methods
3. Results
3.1. Association between 25-OH-D and Cognitive Function
3.2. Association between 25-OH-D and Academic Performance
4. Discussion
Strengths and Limitations
5. Conclusions
Author Contributions
Funding
Acknowledgments
Conflicts of Interest
Abbreviation
25-OH-D | 25-hydroxy vitamin D |
ASC | age-adjusted standard score |
CAP | College of American Pathologists |
LC-MS/MS | liquid chromatography tandem mass spectrometry |
PTH | parathyroid hormone |
RCT | randomized control trials |
SP | school performance |
SPM | Standard Progressive Matrices |
VD | vitamin D |
VDR | vitamin D receptors |
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Characteristics | ||
---|---|---|
Age in years, Mean (SD) years | 12.4 | (0.9) |
n | (%) | |
Gender | ||
Male | 674 | (49.2) |
Nationality | ||
Kuwaiti | 1047 | (76.4) |
Non-Kuwait | 323 | (23.6) |
Father’s Education 1 | ||
No formal education | 15 | (1.11) |
Primary/Intermediate | 215 | (16.1) |
Secondary (high school) | 330 | (24.7) |
Diploma | 251 | (18.8) |
University & above | 526 | (39.3) |
Mother’s Education 2 | ||
No formal education | 31 | (2.3) |
Primary/Intermediate | 145 | (10.7) |
Secondary (high school) | 294 | (21.9) |
Diploma | 293 | (21.7) |
University & above | 587 | (43.5) |
Father’s Income 3 (Kuwaiti Dinars) | ||
Less than 500 | 89 | (6.7) |
500 to 1000 | 291 | (22.0) |
1001 to 1500 | 414 | (31.3) |
1501 to 2000 | 213 | (16.1) |
More than 2000 | 164 | (12.4) |
Do not wish to tell | 153 | (11.6) |
Mother’s Employment Status 4 | ||
Housewife | 466 | (34.7) |
Paid employment | 664 | (49.5) |
Others | 212 | (15.8) |
Housing 5 | ||
Rented flat | 499 | (36.9) |
Rented house | 159 | (11.8) |
Owned flat | 55 | (4.1) |
Owned house | 638 | (47.2) |
Vitamin D Status | Model 1 | Model 2 | Model 3 | Model 4 | Model 5 |
---|---|---|---|---|---|
β [95%CI] | β [95%CI] | β [95%CI] | β [95%CI] | β [95%CI] | |
25-OH-D levels nmol/L | 0.03 | 0.01 | 0.00 | 0.00 | −0.01 |
[−0.02, 0.08] | [−0.04, 0.07] | [−0.05, 0.06] | [−0.05, 0.06] | [−0.07, 0.05] | |
p-value | 0.23 | 0.70 | 0.95 | 0.85 | 0.73 |
Q1 (25-OH-D < 19.2 nmol/L) (n = 337) | [Reference] | [Reference] | [Reference] | [Reference] | [Reference] |
Q2 (25-OH-D ≥ 19.2 to <29.7 nmol/L) (n = 346) | 0.86 | 1.12 | −0.39 | 1.15 | 0.82 |
[−2.65, 4.38] | [−2.32, 4.58] | [−4.28, 3.49] | [−2.29, 4.59] | [−2.82, 4.46] | |
Q3 (25-OH-D from 29.7 to <44.1 nmol/L) (n = 344) | 2.67 | 2.29 | −0.26 | 2.69 | 0.84 |
[−0.86, 6.19] | [−1.43, 6.02] | [−6.25−5.72] | [−1.03, 6.41] | [−3.24, 4.92] | |
Q4 (25-OH-D ≥ 44.1 nmol/L) (n = 343) | 2.91 | 0.95 | −0.70 | 0.50 | −0.42 |
[−0.62, 6.43] | [−3.00, 4.90] | [−7.92, 6.53] | [−3.47, 4.47] | [−4.82, 4.01] | |
p-value | 0.30 | 0.67 | 1.00 | 0.45 | 0.88 |
Severe deficiency (25-OH-D < 25 nmol/L) (n = 544) | [Reference] | [Reference] | [Reference] | [Reference] | [Reference] |
Deficiency (25-OH-D ≥ 25 to <50 nmol/L) (n = 572) | 2.28 | 2.52 | 2.70 | 2.71 | 1.36 |
[−0.46, 5.04] | [−0.39, 5.44] | [0.22, 5.63] | [−0.22, 5.63] | [−1.86, 4.59] | |
Insufficiency (25-OH-D ≥ 50 to <75 nmol/L) (n = 205) | 1.40 | −0.66 | −0.93 | −0.94 | −1.53 |
[−2.36, 5.16] | [−4.66, 3.34] | [−4.94, 3.09] | [−4.97, 3.08] | [−6.01, 2.94] | |
Sufficiency (25-OH-D ≥ 75 nmol/L) (n = 49) | 5.46 | 4.98 | 2.79 | 3.02 | 1.47 |
[−1.39, 12.31] | [−1.96, 11.92] | [−4.16, 9.74] | [−3.93, 9.98] | [−5.96, 8.91] | |
p-value | 0.24 | 0.11 | 0.11 | 0.10 | 0.48 |
Vitamin D Status | Model 1 | Model 2 | Model 3 | Model 4 | Model 5 |
---|---|---|---|---|---|
β [95%CI] | β [95%CI] | β [95%CI] | β [95%CI] | β [95%CI] | |
25-OH-D levels nmol/L | 0.02 | −0.00 | −0.00 | −0.01 | −0.01 |
[−0.01, 0.06] | [−0.03, 0.03] | [−0.04, 0.03] | [−0.04, 0.03] | [−0.04, 0.03] | |
p-value | 0.22 | 0.94 | 0.77 | 0.67 | 0.69 |
Q1 (25-OH-D < 19.2 nmol/L) (n = 337) | [Reference] | [Reference] | [Reference] | [Reference] | [Reference] |
Q2 (25-OH-D ≥19.2 to <29.7 nmol/L) (n = 346) | 1.10 | 1.61 | 2.01 | 1.66 | 1.74 |
[−1.54, 3.74] | [−0.34, 3.57] | [0.01, 4.01] | [−0.42, 3.75] | [−0.33, 3.80] | |
Q3 (25-OH-D from 29.7 to <44.1 nmol/L) (n = 344) | 0.40 | 0.70 | 0.98 | 0.90 | 0.94 |
[−2.15, 2.95] | [−1.58, 2.99] | [−1.26, 3.21] | [−1.39, 3.20] | [−1.41, 3.30] | |
Q4 (25-OH-D ≥ 44.1 nmol/L) (n = 343) | 2.60 | 0.82 | 1.00 | 1.40 | 1.67 |
[0.06, 5.25] | [−1.51, 3.14] | [−1.38, 3.38] | [−1.03, 3.83] | [−0.86, 4.19] | |
p-value | 0.17 | 0.43 | 0.27 | 0.45 | 0.36 |
Severe deficiency (25-OH-D < 25 nmol/L) (n = 544) | [Reference] | [Reference] | [Reference] | [Reference] | [Reference] |
Deficiency (25-OH-D ≥ 25 to <50 nmol/L) (n = 572) | −0.30 | −1.36 | −0.84 | −0.99 | −0.94 |
[−2.35, 1.75] | [−3.04, 0.32] | [−2.65, 0.96] | [−2.73, 0.73] | [−2.88, 0.99] | |
Insufficiency (25-OH-D ≥ 50 to <75 nmol/L) (n = 205) | 2.30 | −0.34 | 0.31 | 0.28 | 0.38 |
[−0.33, 4.93] | [−2.46, 1.77] | [−2.51, 1.88] | [−1.89, 2.47] | [−1.97, 2.73] | |
Sufficiency (25-OH-D ≥ 75 nmol/L) (n = 49) | 3.10 | −1.71 | −1.27 | −2.12 | −1.99 |
[−0.83, 7.03] | [−5.15, 1.73] | [−5.39, 2.84] | [−5.99, 1.74] | [−5.86, 1.89] | |
p-value | 0.08 | 0.38 | 0.78 | 0.35 | 0.45 |
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Rahman, A.; Al-Taiar, A.; Shaban, L.; Al-Sabah, R.; Al-Harbi, A.; Mojiminiyi, O. Plasma 25-Hydroxy Vitamin D Is Not Associated with Either Cognitive Function or Academic Performance in Adolescents. Nutrients 2018, 10, 1197. https://doi.org/10.3390/nu10091197
Rahman A, Al-Taiar A, Shaban L, Al-Sabah R, Al-Harbi A, Mojiminiyi O. Plasma 25-Hydroxy Vitamin D Is Not Associated with Either Cognitive Function or Academic Performance in Adolescents. Nutrients. 2018; 10(9):1197. https://doi.org/10.3390/nu10091197
Chicago/Turabian StyleRahman, Abdur, Abdullah Al-Taiar, Lemia Shaban, Reem Al-Sabah, Anwar Al-Harbi, and Olusegun Mojiminiyi. 2018. "Plasma 25-Hydroxy Vitamin D Is Not Associated with Either Cognitive Function or Academic Performance in Adolescents" Nutrients 10, no. 9: 1197. https://doi.org/10.3390/nu10091197
APA StyleRahman, A., Al-Taiar, A., Shaban, L., Al-Sabah, R., Al-Harbi, A., & Mojiminiyi, O. (2018). Plasma 25-Hydroxy Vitamin D Is Not Associated with Either Cognitive Function or Academic Performance in Adolescents. Nutrients, 10(9), 1197. https://doi.org/10.3390/nu10091197