Table 2.
Main characteristics of included studies examined the relation between serum vitamin D levels and abdominal obesity in children and adolescents.
| References | Study design/name study | Country latitude, °N |
Age range/ Mean age |
Sex | No. Participants | 25 (OH)D Levels, nmol/L | OR, (95% CI) | Method (Exposure) | Definition (Outcome) | Subject | Adjustment |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Tang et al. (15) | Cross-sectional (survey of a school-based interventional project) | South China | 7–18/10 | Both | 2,112 | <16.19 ng/ml 16.20–19.74 19.75–22.99 ≥23 |
1.26 (0.87–1.83) 1.08 (0.74–1.58) 0.98 (0.67–1.44) 1(Ref) |
EIA | WC > 90th percentile for age and gender | Chinese children and adolescents | 1–7 |
| Xiao et al. (25) | Cross-sectional | China | 6–18 | Boys | 3,057 | <30 nmol/l 30–50 ≥50 |
0.78 (0.49–1.23) 1.11 (0.76–1.64) 1(Ref) |
CLIA | WHtR ≥ 0.50 | children and adolescents | 1, 3, 8–15 |
| Girls | 3,034 | <30 nmol/l 30–50 ≥50 |
1.22 (0.80–1.86) 1.15 (0.78–1.69) 1(Ref) |
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| Fu et al. (9) | Cross-sectional (NHANES 2001–2006) | USA | 6–18/12.8 | Both | 6,260 | <30 nmol/l 30–50 >50 |
3·38 (2·60–4·39) 2·28 (1·93–2·68) 1(Ref) |
RIA | WC ≥ 90th percentile | US children | 2, 1, 11, 16–20 |
| Kim et al. (15) | Cross-sectional (KNHANES 2010–2014) | Korea | 12–18/15.14 ± 0.3 | Both | 2,314 | ≤ 20 ng/ml >20 |
1.08 (0.58–2.02) 1(Ref) |
NR | WC ≥ 90th percentile (if ≥16 years, boys ≥90 cm, girls ≥ 85 cm) | Korean adolescents | 1–3, 9, 20–24 |
| Cabral et al. (14) | Cross-sectional (EPITeen 2003–2004) | Portugal | 13 | Both | 514 | <13.0 ng/ml 13.0–16.0 17.0–20.0 >20.0 |
1.26 (0.48–3.29) 1.03 (0.36–2.89) 1.64 (0.58–4.50) 1(Ref) |
CLIA | WC ≥ 75th percentile for age and gender | Adolecsents | 2, 3, 8, 13, 25 |
| Cediel et al. (8) | Cross-sectional (GOCS) | Santiago, Chile | 8.0 ± 1.3 6.3 ± 0.6 |
Boys Girls |
203 232 |
<30 ng/ml ≥30 <30 ng/ml ≥30 |
2.2 (1.2–4.0) 1(Ref) 2.4 (1.4–4.3) 1(Ref) |
IA | WC ≥ 75th percentile (NHANES III percentiles Mexican–Children: cut-off ≥75th percentile in girls at 6 years: 60.4 cm; and boys at 8 years: 66.2 cm) | Prepubertal chilean children | 1, 8 |
| Al-Daghri et al. (26) | Cross-sectional | Riyadh, Saudi Arabia | 12–17/14.3 | Boys | 1,906 | <25 nmol/l 25–50 ≥50 |
1.30 (0.49–3.43) 1.55 (0.73–3.31) 1(Ref) |
CLIA | WHtR > 0.56 | Apparently healthy Saudi school students | – |
| Girls | 2,277 | <25 nmol/l 25–50 ≥50 |
1.45 (0.66–3.19) 1.19 (0.54–2.65) 1(Ref) |
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| Al-Daghri et al. (27) | Cross-sectional | Riyadh, Saudi Arabia | 13–17/15.1 | Boys | 1,187 | <25 nmol/l 25–49.9 >50 |
(0.32–3.10) 2.75 (1.1–7.1) 1(Ref) |
IA | WC > 90th percentile (>92 cm for boys and >86 cm for Girls) | Saudi adolescents | 1, 13, 26–30 |
| Girls | 1,038 | <25 nmol/l 25–49.9 >50 |
1.31 (0.38–4.45) 1.27 (0.36–4.42) 1(Ref) |
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| De Piero Belmonte et al. (28) | Cross-sectional | Spain | 8–13/10.7 ± 1.0 | Both | 314 | 4.0–19.4 ng/mL 19.5–25.3 25.4–55.5 |
1(Ref) 1.14 (0.63–2.05) 0.77 (0.56–1.07) |
CLIA | WC ≥ 90th percentile | Spanish school-children | 1, 2 |
| Jari et al. (29) | Cross-sectional (CASPIAN-III study) | 27 provinces in Iran | 10–18 | Boys | 568 | <10 ng/ml 10–30 ≥30 |
1.07 (0.55, 2.05) (0.56–2.14) 1(Ref) |
CLIA | WHtR >0.5 | Students | 1, 9 |
| Girls | 527 | <10 ng/ml 10–30 ≥30 |
0.69 (0.35, 1.35) 0.91 (0.48, 1.74) 1(Ref) |
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| Nam et al. (18) | Cross-sectional (KNHANES 2008–2009) | South Korea | 12–18/ | Both | 1,504 | ≤ 50 nmol/l >50 |
2.05 (1.20-3.49) 1(Ref) |
RIA | WC ≥ 90th percentile for age and gender | Adolecsents | 1–3, 11, 31 |
| Lee et al. (22) | Cross-sectional (Ewha Birth and Growth Cohort study 2001–2006) | Korea | 7–9/7.89 | Both | 205 | Per 1 ng/mL increase of 25(OH)D | 0.87 (0.75–1.01) | RIA | WC ≥ 90th percentile | Preadolescent children | 1, 2, 25, 32, 33 |
| Lee et al. (7) | Cross-sectional (KMOSES) 2006–2010) | South Korea | 9 | Both | 1,649 | <15.5 ng/ml 15.5–18.3 18.4–21.6 >21.6 |
2.96 (1.75–5.00) 2.32 (1.36–3.95) 2.08 (1.20–3.60) 1(Ref) |
CLIA | WC > 90th percentile for age and gender | Children | 13 |
| Pacifico et al. (30) | Cross-sectional | Rome, Italy | 11.2 | Both | 452 | <17.0 ng/ml 17.0–27.0 >27 |
1.98 (0.83–4.73) 1.20 (0.75–1.91) 1(Ref) |
ECLIA | WC ≥ 90th percentile for age and gender | Caucasian children and adolescents | 1, 2, 13, 34 |
Ref, reference; WC, waist circumference; IA, immunoassay; CLIA, chemiluminescent immunoassay; EIA, enzyme-immunosorbent assay; RIA, radioimmunoassay; ECLIA, electrochemiluminescence immunoassay; NHANES, national health and nutrition examination surveys; EPITeen, epidemiological health investigation of teenagers; KNHANES, Korea national health and nutrition examination survey; GOCS, growth and obesity Chilean cohort study; CASPIAN, childhood and adolescence surveillance and prevention of adult noncommunicable disease; KMOSES, Korean metabolic disorders and obesity study in elementary school Childre; WHtR, waist to height ratio. Adjustments: 1, Age; 2, sex; 3, physical activity; 3, sun exposure time; 4, screen time; 5, intake of fruit; 6, intake vegetables; 7, intake of meat products; 8, season of blood collection; 9, geographical location; 10, smoking; 11, drinking; 12, dietary vitamin D intake; 13, Body mass index (BMI); 14, fat mass percentage (FMP); 15, muscle mass index (MMI); 16, cotinine concentration; 17, race; 18, ethnicity; 19,poverty; 20, income ratio; 21, self-perceived health status; 22, self-perceived stress status; 23, family history of chronic disease; 24, sleep; 25, parental education; 26, glucose; 27, total cholesterol; 28, triglycerides; 29, High-density lipoproteins cholesterol (HDL-c); 30, Low- density lipoproteins cholesterol (LDL-c); 31, use of multivitamin or mineral supplement; 32, birth order; 33,fruit/fruit juice intake; 34,Tanner stage.