Vitamin D in youth with Type 1 diabetes: prevalence of insufficiency and association with insulin resistance in the SEARCH Nutrition Ancillary Study
Article first published online: 29 AUG 2013
© 2013 The Authors. Diabetic Medicine © 2013 Diabetes UK
Volume 30, Issue 11, pages 1324–1332, November 2013
How to Cite
Diabet. Med. 30, 1324–1332 (2013)
- Issue published online: 17 OCT 2013
- Article first published online: 29 AUG 2013
- Accepted manuscript online: 3 AUG 2013 01:52AM EST
- Manuscript Accepted: 30 JUL 2013
- NIH/NIDDK. Grant Number: R01 DK077949
- Centers for Disease Control and Prevention. Grant Numbers: 00097, DP-05-069, DP-10-001
- National Institute of Diabetes and Digestive and Kidney Diseases. Grant Numbers: U48/CCU919219, U01 DP000246, U18DP002714
- University of Colorado Denver. Grant Numbers: U48/CCU819241-3, U01 DP000247, U18DP000247-06A1
- Kuakini Medical Center . Grant Numbers: U58CCU919256, U01 DP000245
- Children's Hospital Medical Center. Grant Numbers: U48/CCU519239, U01 DP000248 , 1U18DP002709
- University of North Carolina at Chapel Hill. Grant Numbers: U48/CCU419249, U01 DP000254, U18DP002708-01
- University of Washington School of Medicine . Grant Numbers: U58/CCU019235-4, U01 DP000244, U18DP002710-01
- Wake Forest University School of Medicine. Grant Numbers: U48/CCU919219, U01 DP000250, 200-2010-35171
To determine the prevalence of plasma vitamin D (25-dihydroxyvitamin D) insufficiency in individuals with Type 1 diabetes and to determine the cross-sectional and longitudinal associations of plasma vitamin D with insulin resistance.
Participants from the SEARCH for Diabetes in Youth Study [n = 1426; mean age 11.2 years (sd 3.9)] had physician-diagnosed Type 1 diabetes [diabetes duration mean 10.2 months (sd 6.5)] with data available at baseline and follow-up (approximately 12 and 24 months after baseline). Insulin resistance was estimated using a validated equation. Cross-sectional and longitudinal multivariate logistic regression models were used to determine the association of plasma vitamin D with insulin resistance, adjusting for potential confounders.
Forty-nine per cent of individuals had plasma vitamin D < 50 nmol/l and 26% were insulin resistant. In cross-sectional multivariate analyses, participants who had higher plasma vitamin D (65 nmol/l) had lower odds of prevalent insulin resistance than participants with lower plasma vitamin D (25 nmol/l) (odds ratio 0.70, 95% CI 0.57–0.85). This association was attenuated after additional adjustment for BMI z-score, which could be a confounder or a mediator (odds ratio 0.81, 95% CI 0.64–1.03). In longitudinal multivariate analyses, individuals with higher plasma vitamin D at baseline had lower odds of incident insulin resistance, but this was not significant (odds ratio 0.85, 95% CI 0.63–1.14).
Vitamin D insufficiency is common in individuals with Type 1 diabetes and may increase risk for insulin resistance. Additional prospective studies are needed to determine the association between plasma vitamin D and insulin resistance, and to further examine the role of adiposity on this association.