The Relationship between Vitamin D Status and Allergic Diseases in New Zealand Preschool Children
Abstract
:1. Introduction
2. Materials and Methods
2.1. Study Design and Participants
2.2. Data Collection
2.3. Measurement of 25(OH)D Concentrations
2.4. Disease Outcome Measures
2.5. Statistical Analyses
3. Results
3.1. Participant Characteristics
3.2. Disease Outcomes
4. Discussion
5. Conclusions
Acknowledgments
Author Contributions
Conflicts of Interest
Abbreviations
LC-MS/MS | liquid chromatography with tandem mass-spectrometer |
25(OH)D | 25 hydroxyvitamin D |
1-25(OH)2D | 1,25 di-hydroxyvitamin D |
Th2 | T helper 2 cells |
IgE | immunoglobulin E |
DBS | dried blood spot |
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Variable | n (%) | 25(OH)D Categories (nmol/L) n (%) | |||
---|---|---|---|---|---|
<25 | 25 to 49.9 | 50 to 74.9 | ≥75 | ||
Total | 1329 | 86 (7) | 556 (42) | 541 (41) | 146 (11) |
Mean (95%CI) (nmol/L) | 52 (19) | 19 (18–20) | 39 (39–40) | 61 (60–61) | 87 (85–90) |
Median | 51 | 20 | 40 | 60 | 82 |
Interquartile Range (IQ) | 25 | 7 | 12 | 12 | 14 |
Age (years) | |||||
2 years old | 496 (37) | 30 (6) | 223 (45) | 183 (37) | 60 (12) |
3 years old | 448 (34) | 25 (6) | 180 (40) | 194 (43) | 49 (11) |
4 years old | 385 (29) | 31 (8) | 153 (40) | 164 (43) | 37 (10) |
Gender | |||||
Female | 648 (49) | 51 (8) | 296 (46) | 248 (38) | 53 (8) |
Male | 681 (51) | 35 (5) | 260 (38) | 293 (43) | 93 (14) |
Ethnicity | |||||
NZ European | 926 (70) | 32 (3) | 378 (41) | 401 (43) | 115 (12) |
Māori | 174 (13) | 16 (9) | 74 (43) | 66 (38) | 18 (10) |
Pacific | 44 (3) | 10 (23) | 21 (48) | 12 (27) | 1 (2) |
Other non-European | 185 (14) | 28 (15) | 83 (45) | 62 (34) | 12 (7) |
Skin colour—parental report | |||||
Very fair—fair | 767 (58) | 27 (4) | 339 (44) | 313 (41) | 88 (11) |
Medium | 445 (33) | 29 (7) | 172 (39) | 193 (43) | 51 (11) |
Olive—very dark | 17 (9) | 30 (26) | 45 (38) | 35 (30) | 7 (6) |
Attend formal daycare | |||||
Yes | 1137 (86) | 71 (6) | 464 (41) | 473 (42) | 129 (11) |
No | 192 (14) | 15 (8) | 92 (48) | 68 (35) | 17 (9) |
Vitamin D supplement use * | |||||
Yes | 253 (19) | 6 (2) | 78 (31) | 131 (52) | 38 (15) |
No | 1076 (81) | 80 (7) | 478 (44) | 410 (38) | 108 (10) |
Drinks toddler milk | |||||
Yes | 80 (6) | 0 (0) | 20 (25) | 44 (55) | 16 (20) |
No | 1249 (94) | 86 (7) | 536 (43) | 497 (40) | 130 (10) |
Maternal-education qualifications | |||||
No secondary | 59 (4) | 20 (34) | 23 (39) | 13 (22) | 3 (5) |
Secondary | 98 (15) | 10 (5) | 93 (47) | 77 (39) | 18 (9) |
Post-secondary | 1072 (81) | 56 (5) | 440 (41) | 451 (42) | 125 (12) |
Allergic Disease 25(OH)D Concentration (nmol/L) | n | Unadjusted | Adjusted * | ||
---|---|---|---|---|---|
OR (95%CI) | p Value | OR (95%CI) | p Value | ||
Atopic asthma (n = 420) | |||||
<25 | 25 | 0.96 (0.58, 1.58) | 0.87 | 0.81 (0.46, 1.41) | 0.45 |
25 to 49.9 | 184 | 1.16 (0.90, 1.49) | 0.26 | 1.19 (0.91, 1.55) | 0.21 |
50 to 74.9 | 162 | 1.00 | - | 1.00 | - |
≥75 | 49 | 1.18 (0.80, 1.75) | 0.40 | 1.13 (0.76, 1.69) | 0.55 |
Eczema (n = 299) | |||||
<25 | 15 | 0.78 (0.43, 1.42) | 0.42 | 0.66 (0.34, 1.29) | 0.22 |
25 to 49.9 | 132 | 1.15 (0.87, 1.53) | 0.33 | 1.20 (0.92, 1.55) | 0.26 |
50 to 74.9 | 115 | 1.00 | - | 1.00 | - |
≥75 | 37 | 1.26 (0.82, 1.93) | 0.29 | 1.23 (0.79, 1.89) | 0.36 |
Food allergy(n = 153) | |||||
<25 | 4 | 0.45 (0.16, 1.27) | 0.13 | 0.45 (0.15, 1.36) | 0.16 |
25 to 49.9 | 67 | 1.26 (0.86, 1.85) | 0.23 | 1.39 (0.93, 2.06) | 0.21 |
50 to 74.9 | 53 | 1.00 | - | 1.00 | - |
≥75 | 29 | 2.82 (1.39, 3.75) | <0.001 | 2.21 (1.33, 3.68) | 0.002 |
Allergic rhinoconjunctivitis (n = 139) | |||||
<25 | 14 | 1.91 (1.01, 3.63) | 0.05 | 1.82 (0.89, 3.72) | 0.10 |
25 to 49.9 | 56 | 1.10 (0.74, 1.64) | 0.64 | 1.14 (0.75, 1.72) | 0.54 |
50 to 74.9 | 50 | 1.00 | - | 1.00 | - |
≥75 | 19 | 1.47, (0.84, 2.58) | 0.18 | 1.45 (0.82, 2.58) | 0.20 |
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Cairncross, C.; Grant, C.; Stonehouse, W.; Conlon, C.; McDonald, B.; Houghton, L.; Eyles, D.; Camargo, C.A., Jr.; Coad, J.; Von Hurst, P. The Relationship between Vitamin D Status and Allergic Diseases in New Zealand Preschool Children. Nutrients 2016, 8, 326. https://doi.org/10.3390/nu8060326
Cairncross C, Grant C, Stonehouse W, Conlon C, McDonald B, Houghton L, Eyles D, Camargo CA Jr., Coad J, Von Hurst P. The Relationship between Vitamin D Status and Allergic Diseases in New Zealand Preschool Children. Nutrients. 2016; 8(6):326. https://doi.org/10.3390/nu8060326
Chicago/Turabian StyleCairncross, Carolyn, Cameron Grant, Welma Stonehouse, Cath Conlon, Barry McDonald, Lisa Houghton, Darryl Eyles, Carlos A. Camargo, Jr., Jane Coad, and Pamela Von Hurst. 2016. "The Relationship between Vitamin D Status and Allergic Diseases in New Zealand Preschool Children" Nutrients 8, no. 6: 326. https://doi.org/10.3390/nu8060326
APA StyleCairncross, C., Grant, C., Stonehouse, W., Conlon, C., McDonald, B., Houghton, L., Eyles, D., Camargo, C. A., Jr., Coad, J., & Von Hurst, P. (2016). The Relationship between Vitamin D Status and Allergic Diseases in New Zealand Preschool Children. Nutrients, 8(6), 326. https://doi.org/10.3390/nu8060326