Diabetes after giving birth was associated with low vitamin D combined with high PTH – May 2014

Prospective Associations of Vitamin D Status with Beta-cell function, Insulin Sensitivity and Glycemia: The Impact of Parathyroid Hormone Status.

Diabetes. 2014 May 29. pii: DB_140489. [Epub ahead of print]
Kramer CK1, Swaminathan B2, Hanley AJ3, Connelly PW4, Sermer M5, Zinman B6, Retnakaran R7.

• 1Leadership Sinai Centre for Diabetes, Mount Sinai Hospital, Toronto, Canada Division of Endocrinology, University of Toronto, Toronto, Canada.
• 2Leadership Sinai Centre for Diabetes, Mount Sinai Hospital, Toronto, Canada.
• 3Leadership Sinai Centre for Diabetes, Mount Sinai Hospital, Toronto, Canada Division of Endocrinology, University of Toronto, Toronto, Canada Department of Nutritional Sciences, University of Toronto, Toronto, Canada.
• 4Division of Endocrinology, University of Toronto, Toronto, Canada Keenan Research Centre for Biomedical Science of St. Michael's Hospital, Toronto, Canada.
• 5Division of Obstetrics and Gynecology, University of Toronto, Toronto, Canada.
• 6Leadership Sinai Centre for Diabetes, Mount Sinai Hospital, Toronto, Canada Division of Endocrinology, University of Toronto, Toronto, Canada Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Canada.
• 7Leadership Sinai Centre for Diabetes, Mount Sinai Hospital, Toronto, CanadaDivision of Endocrinology, University of Toronto, Toronto, CanadaLunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Canada rretnakaran at mtsinai.on.ca.

Previous studies have yielded conflicting findings on the relationship between low vitamin D (25-OH-D) and impaired glucose homeostasis. In this context, we hypothesized that combined assessment of 25-OH-D with its regulator parathyroid hormone (PTH) may be required for optimal evaluation of the impact of vitamin D status on glucose metabolism. Thus, we evaluated the prospective associations of 25-OH-D and PTH at 3-months postpartum with beta-cell function (Insulin Secretion-Sensitivity Index-2 (ISSI-2)), insulin sensitivity (Matsuda index) and glycemia at 12-months postpartum in 494 women undergoing serial metabolic characterization.

Notably, 32% of those with pre-diabetes/diabetes at 12-months postpartum had both vitamin D deficiency and PTH in the highest tertile at 3-months postpartum.

On multiple-adjusted linear regression analyses, vitamin D deficiency/insufficiency with PTH in the highest tertile at 3-months independently predicted

• poorer beta-cell function (P=0.03) and
• insulin sensitivity (P=0.01), and
• increased fasting (P=0.03) and
• 2-hour glucose (P=0.002) at 12-months postpartum.

In contrast, vitamin D deficiency/insufficiency with lower PTH did not predict these outcomes.
In conclusion, only vitamin D deficiency/insufficiency with increased PTH is an independent predictor of beta-cell dysfunction, insulin resistance and glycemia, highlighting the need for consideration of the PTH/25-OH-D axis when studying the impact of vitamin D status on glucose homeostasis.

© 2014 by the American Diabetes Association.

PMID: 24875346

---

See also VitaminDWiki

• Overview Diabetes and vitamin D
• Overview Thyroid and Vitamin D

Pages listed in BOTH of the categories Diabetes and Thyroid/PTH