Risk factors of vitamin D deficiency among 15-year-old adolescents participating in the Malaysian Health and Adolescents Longitudinal Research Team Study (MyHeARTs)

Abstract

BackgroundThis study is to determine the prevalence and risk factors of vitamin D deficiency (vitamin D ≤ 50 nmol/L) among 15-year-old Malaysian adolescents. By identifying potential risk factors, prevention strategies and interventions can be carried out to improve the vitamin D status in adolescents.Methods and findingsStratified random sampling design was used to select adolescents from 15 urban and rural secondary schools in Selangor, Perak and Kuala Lumpur, Malaysia. Data collection was carried out from 1st April 2014 to 30th June 2014. Information regarding socio-demographic characteristics, sun exposure and sun protective behaviours, clinical data and environmental factors were collected. Blood for total vitamin D was sampled. Descriptive and multivariate logistic regressions were performed. Total 1061 participants were analyzed (62% were female; mean age 15.1 ± 0.4 years). The prevalence of vitamin D deficiency was 33%. Mean vitamin D was lower in female (53 ± 15 nmol), obese (body fat percentage (≥25%m; ≥33.8%f) (56 ± 16 nmol/L), Malays (58 ± 18 nmol/L) and Indians (58 ± 15 nmol/L). In multivariate analysis, female (OR = 5.5; 95% CI: 3.4–7.5), Malay (OR = 3.2; 95% CI: 1.3–8.0), Indian (OR = 4.3; 95% CI: 1.6–12.0) and those always wearing long sleeve (OR = 2.4; 95% CI: 1.1–5.4) were more likely to have vitamin D deficiency. For female participants, ethnicity {Malays (OR = 6.7; 95% CI: 2.0–18.5), Indian (OR = 4.5; 95% CI: 1.8–19.3)} was an important risk factors. Cloud cover, school residence, skin pigmentation, sun-exposure and sun-protective behaviours were not significant risk factors. The limitation of this study was recall bias as it relied on self-reported on the sun exposure and protective behaviours. The diet factors were not included in this analysis.ConclusionsThe prevalence of Vitamin D deficiency among Malaysian adolescents was considerable. Gender, ethnicity and clothing style were important risk factors.

Assessment of Awareness, Knowledge, Attitude, and the Practice of Vitamin D among the General Public in Malaysia

“…Our findings are aligned to results of previous studies. 16,[29][30][31][32] It had shown that breast milk contains an insufficient amount of vitamin D for infants and thus, exclusively breastfed infants should be supplemented with vitamin D. 33 However, only 6% of the participants recognised that formula milk is the source of Vitamin D for infants instead of breast milk, regardless of gender. The possible reason for this might be due to the opinion of public that breast milk contains all required nutrients for infants.…”

Status and influential factors of vitamin D among children aged 0 to 6 years in a Chinese population

“…Vitamin D deficiency and insufficiency are global problems [19][20][21]. Our study found that a high prevalence of vitamin D deficiency and insufficiency among children aged 0-6 years old in a Chinese population, especially in the preschool-aged children.…”

Status and influential factors of vitamin D among children aged 0 to 6 years in a Chinese population

“…Vitamin D deficiency and insufficiency are global problems [15][16][17]. Our study found that a high prevalence of vitamin D deficiency and insufficiency among children aged 0-6 years old in a Chinese population, especially in the preschool-aged children.…”