Vitamin D status and predictors of hypovitaminosis D in Italian children and adolescents: a cross-sectional study.
Eur J Pediatr. 2013 Aug 20.
Vierucci F, Del Pistoia M, Fanos M, Gori M, Carlone G, Erba P, Massimetti G, Federico G, Saggese G.
Pediatric Unit, Department of Pediatrics, Santa Chiara University Hospital, Via Roma 67, 56126, Pisa, Italy, vieruf at hotmail.it.
Hypovitaminosis D affects children and adolescents all around the world. Italian data on vitamin D status and risk factors for hypovitaminosis D during pediatric age are lacking. Six hundred fifty-two children and adolescents (range 2.0-21.0 years) living in the northwestern area of Tuscany were recruited at the Department of Pediatrics, University Hospital Pisa. None of them had received vitamin D supplementation in the previous 12 months. 25-hydroxyvitamin D (25-OH-D) and parathyroid hormone (PTH) levels were analyzed in all subjects. Severe vitamin D deficiency was defined as serum levels of 25-OH-D < 25.0 nmol/L (10.0 ng/mL) and vitamin D deficiency as < 50.0 nmol/L (20.0 ng/mL). Serum 25-OH-D levels of 50.0-74.9 nmol/L (20.0-29.9 ng/mL) indicated vitamin D insufficiency, whereas 25-OH-D levels ≥ 75.0 nmol/L (30.0 ng/mL) were considered sufficient. Hypovitaminosis D was defined as 25-OH-D levels < 75.0 nmol/L (30.0 ng/mL). The median serum 25-OH-D level was 51.8 nmol/L, range 6.7-174.7 (20.7 ng/mL, range 2.7-70.0), with a prevalence of vitamin D deficiency, insufficiency, and sufficiency of 45.9, 33.6, and 20.5 %, respectively. The prevalence of severe vitamin D deficiency was 9.5 %. Adolescents had lower median 25-OH-D levels (49.8 nmol/L, range 8.1-174.7; 20.0 ng/mL, range 3.2-70.0) than children (55.6 nmol/L, range 6.8-154.6; 22.3 ng/mL, range 2.7-61.9, p = 0.006). Non-white individuals (n = 37) had median serum 25-OH-D levels in the range of deficiency (28.2 nmol/L, range 8.1-86.2; 11.3 ng/mL, range 3.2-34.5), with 36/37 having hypovitaminosis D. Logistic regression showed significant increased risk of hypovitaminosis D in the following: blood samples taken in winter (odds ratio (OR) 27.20), spring (OR 26.44), and fall (OR 8.27) compared to summer; overweight (OR 5.02) and obese (OR 5.36) subjects compared to individuals with normal BMI; low sun exposure (OR 8.64) compared to good exposure, and regular use of sunscreens (OR 7.06) compared to non-regular use.
Gender and place of residence were not associated with vitamin D status.
The 25-OH-D levels were inversely related to the PTH levels (r = -0.395, p < 0.0001).
Sixty-three out of the 652 (9.7 %) subjects showed secondary hyperparathyroidism.
Conclusion Italian children and adolescents who were not receiving vitamin D supplementation had high prevalence of hypovitaminosis D.
Careful identification of factors affecting vitamin D status is advisable to promptly start vitamin D supplementation in children and adolescents.
|Low sun exposure||9X|
|Use of sunscreens||7X|
Seems similar to other studies. Interesting that they did not study skin color, which might have been a 10X to 100X factor
- Virtually all Chinese teens at 30 degree N have less than 30 ng of vitamin D – Feb 2012
- 75 percent of children in NE US had less than 20 ng of vitamin D in winter – Dec 2011
- Children still need 30 ng of vitamin D – Nov 2011
- Obese teens needed 4000 IU of vitamin D - Nov 2011
- Vitamin D deficiency 4X more likely in Italian teens if: dark skin, winter, obese, little sun, or use sunscreen – June 2014 same authors as study on this page - has provisional PDF