Changes in vitamin D and parathyroid hormone metabolism in incident pediatric Crohn's disease.

Abstract

BACKGROUND:

Prior studies of vitamin D metabolism in Crohn's disease (CD) did not include controls or examine changes following diagnosis. This study examined associations among 25-hydroxyvitamin D [25(OH)D], 1,25-dihydroxyvitamin D [1,25(OH)(2)D], and parathyroid hormone (PTH) levels in incident pediatric CD, compared with controls, and following diagnosis.

METHODS:

Serum vitamin D and PTH were measured at diagnosis (n = 78), 6, 12, and a median of 43 months (n = 52) later in CD participants, and once in 221 controls. Multivariate regression was used to examine baseline associations and quasi-least squares regression to assess subsequent changes.

RESULTS:

At diagnosis, 42% of CD participants were 25(OH)D-deficient (<20 ng/mL). The odds ratio for deficiency was 2.1 (95% confidence interval [CI]: 1.1, 3.9; P < 0.05) vs. controls, adjusted for age, race, and season. 1,25(OH)(2)D was lower in CD vs. controls (P < 0.05), adjusted for 25(OH)D, tumor necrosis factor alpha (TNF-α), and PTH. TNF-α was associated with lower 1,25(OH)(2)D (P < 0.05), and the positive association between PTH and 1,25(OH)(2)D in controls was absent in CD (interaction P = 0.02). Among participants with 25(OH)D <30 ng/mL, CD was associated with lower PTH (P < 0.05) vs. controls. Following diagnosis, 25(OH)D and 1,25(OH)(2)D improved (P < 0.001). At the final visit, 3% were 25(OH)D-deficient, PTH was no longer low relative to 25(OH)D, and 1,25(OH)(2)D was significantly elevated (P < 0.001) compared with controls.

CONCLUSIONS:

Incident CD was associated with 25(OH)D and 1,25(OH)2D deficiency and a relative hypoparathyroidism that resolved following diagnosis. Inflammatory cytokine suppression of PTH and renal 1-α-hyroxylase may contribute to these alterations.

• Authors: Aaron R Prosnitz, Mary B Leonard, Justine Shults, Babette S Zemel, Bruce W Hollis, Lee A Denson, Robert N Baldassano, Aaron B Cohen, Meena Thayu
• Journal: Inflammatory bowel diseases (Inflamm Bowel Dis) Vol. 19 Issue 1 Pg. 45-53 (Jan 2013) ISSN: 1536-4844 [Electronic] England
• PMID: 22488969 (Publication Type: Comparative Study, Journal Article, Research Support, N.I.H., Extramural, Research Support, Non-U.S. Gov't)

Chemical References

• Parathyroid Hormone
• Tumor Necrosis Factor-alpha
• Vitamin D
• 1,25-dihydroxyvitamin D
• 25-hydroxyvitamin D

Topics

• Adolescent
• Adult
• Body Composition
• Case-Control Studies
• Child
• Child, Preschool
• Cohort Studies
• Crohn Disease (epidemiology, metabolism)
• Female
• Follow-Up Studies
• Humans
• Male
• Parathyroid Hormone (blood)
• Prognosis
• South Carolina (epidemiology)
• Tumor Necrosis Factor-alpha (blood)
• Vitamin D (administration & dosage, analogs & derivatives, blood)
• Vitamin D Deficiency (blood, etiology)
• Young Adult