SERUM SCLEROSTIN LEVELS IN ACROMEGALY

Program: Abstracts - Orals, Featured Poster Presentations, and Posters
Session: SAT 109-133-GHRH, GH & IGF Biology & Signaling
Bench to Bedside
Saturday, June 15, 2013: 1:45 PM-3:45 PM
Expo Halls ABC (Moscone Center)

Poster Board SAT-125
Selcuk Dagdelen*1, Safak Akin2 and Tomris Erbas1
1Hacettepe University Medical School, Ankara, Turkey, 2Hacettepe University School of Medicine, Ankara, Turkey
Background: Sclerostin is an osteocyte secretion which regulates bone-remodelling on both osteoblast and osteoclast functions. Acromegaly increases bone turnover, as determined by changes in biochemical markers and bone histomorphometry.  There is no data about sclerostin levels in patients with acromegaly.

Aim: The aims of this study were 1) to evaluate serum sclerostin levels in patients with acromegaly compared with age- sex and body mass index (BMI)- matched control subjects and 2) to analyze the relationship between sclerostin and PTH, 25- hydroxyvitamin D [25(OH)D], or bone mineral density (BMD) in patients with  acromegaly.

Materials and Methods: Thirty-two [n:32, mean age: 48.7±9.4 yrs, M/F:21/11, BMI: 31.8±6.0 kg/m²] patients with acromegaly routinely followed at university hospital were studied. Thirty-four (n:34) age – sex, and BMI (46.2±4.1 yrs, M/F: 28/6, 29.3±4.4 kg/m²)  matched subjects were enrolled as the control group.

Results: Serum calcium, 25(OH)D and PTH levels were similar in both groups. No significant difference was observed in femur neck and vertebral T scores. Patients with acromegaly had significantly lower sclerostin levels than the controls (15.4± 8.4 pmol/L vs. 20.6±9.2, p=0.022). Sclerostin levels were similar both in males and females patients with acromegaly (15.1±4.7 vs 15.6±9.9 pmol/L). Sclerostin levels were similiar in patients with active acromegaly (n:8, 11.8±8.5 pmol/L)  and controlled acromegaly (n:24, 16.6±8.2 pmol/L). There was no significant correlation between sclerostin and GH, IGF-1 and prolactin levels (r= 0.029; p=0.87, r=-0.065; p=0.72, r=-0.002; p=0.99, respectively).

The prevalence of hypovitaminosis D ( <20 ng/ml) was similiar in acromegalic patients and controls (59.5% and 76.5% respectively, p=0.13). No significant correlation was found between 25(OH)D and sclerostin levels in all participiants. The prevalence of osteoporosis was 21.9% in patients with acromegaly. No significant correlation was found between sclerostin levels and presence of osteoporosis in patients with acromegaly.

Conclusion: Our study is the first report showing a significant lower serum sclerostin levels in acromegaly compared with healthy control subjects. Further studies are required to establish the clinical relevance of sclerostin and GH/IGF1 axes interaction.

Nothing to Disclose: SD, SA, TE

*Please take note of The Endocrine Society's News Embargo Policy at http://www.endo-society.org/endo2013/media.cfm