Vitamin D increases circulating IGF1 in adults: potential implication for treatment of growth hormone deficiency.

[helvella]

Although very few thyroid patients are ever tested in any way for growth hormone, there is sufficient research to suggest that it can be low-ish in those with thyroid issues. This paper suggests a possibility that vitamin D may be somewhat beneficial in this direction.

The paper is directed at people receiving growth hormone treatment. It is my leap to suggest that this could be an area where the effect of vitamin D has previously not been understood in thyroid disorders. (Even if people have appreciated the improvements due to a decent vitamin D level.)

IGF1 = Insulin-like growth factor

en.wikipedia.org/wiki/Insul...

Eur J Endocrinol. 2013 Sep 4. [Epub ahead of print]

Vitamin D increases circulating IGF1 in adults: potential implication for treatment of growth hormone deficiency.

Ameri P, Giusti A, Boschetti M, Bovio M, Teti C, Leoncini G, Ferone D, Murialdo G, Minuto FM.

Source

P Ameri, Department of Internal Medicine, University of Genova, Genova, Italy.

Abstract

OBJECTIVES:

Previous studies suggested that vitamin D modulates circulating IGF1. We investigated this effect in adults and its clinical relevance in the management of growth hormone deficiency (GHD).

DESIGN AND METHODS:

IGF1 levels were prospectively measured before and after 12 weeks of treatment with oral vitamin D3 (5000 or 7000 IU/week) vs. no intervention in 39 subjects 61.9±7.9 years old. The frequency of IGF1 values ≥ 50th age- and sex-specific percentile in relation to vitamin D status, as determined by the concentration of 25-hydroxyvitamin D [25(OH)D], was retrospectively assessed in 69 GHD patients (57.4±16.6 yr) on stable hormone replacement and with 25(OH)D and IGF1 concurrently measured.

RESULTS:

Five-thousand and 7000 IU vitamin D3/week significantly raised 25(OH)D by 12.7±8.4 ng/ml and 13.1±6.5 ng/ml, respectively (both P < 0.001 vs. baseline). In the 7000 IU group IGF1 levels also significantly increased by 31.3±36.7 ng/ml (P = 0.01). Neither 25(OH)D nor IGF1 significantly varied in controls. IGF1 was ≥ 50th percentile more frequently in GHD patients with ≥ 15 ng/ml than < 15 ng/ml 25(OH)D (65.9% vs. 40.0%, P < 0.05). Logistic regression with adjustment for recombinant human (rh) GH dose, vitamin D supplements, gender, use of thyroid hormones, corticosteroids or estrogen/testosterone, and season revealed a significant positive association between ≥ 15 ng/ml 25(OH)D and IGF1 ≥50th percentile (OR 4.4, 95% CI 1.0-18.8, P < 0.05). A significant negative correlation between 25(OH)D concentrations and rhGH dose was found after correcting for age and IGF1 (β - 0.042, P < 0.01), but not after further adjusting for sex, thyroid, adrenal or gonadal replacement, and season (β - 0.037, P = 0.06).

CONCLUSIONS:

Vitamin D increases circulating IGF1 in adults. As a result, a better vitamin D status may ease the achievement of normal IGF1 values in GHD.

PMID:

24005315

[PubMed - as supplied by publisher]

ncbi.nlm.nih.gov/pubmed/240...

Rod

[nightingale-56]

Thanks for this info Rod - a bit more info for questions to ask endo when I next see him regarding my son. Janet.

[helvella Administrator Thyroid UK in reply to nightingale-56]

I hope it throws another jigsaw piece into play.

[halifaxlass]

The only vitamin I've ever been found to be low is D, I'm underactive thyroid & have recently been diagnosed with severe growth hormone deficiency........................................ Thanks Rod, interesting article.