Low serum osteocalcin levels in glucocorticoid-treated asthmatics

Area of Science:

• Endocrinology
• Pulmonology
• Bone Metabolism

Background:

• Asthma management often involves long-term glucocorticoid therapy.
• Glucocorticoids are known to affect bone metabolism.
• Osteocalcin (OC) is a key marker of bone formation.

Purpose of the Study:

• To investigate the effect of long-term glucocorticoid therapy on serum osteocalcin (OC) levels in asthmatic patients.
• To explore the relationship between OC, 1,25-dihydroxyvitamin D [1,25-(OH)2D], and glucocorticoid dosage.
• To assess the impact of vitamin D supplementation on OC levels in patients on glucocorticoids.

Main Methods:

• Serum OC and 1,25-(OH)2D levels were measured in asthmatic patients on long-term glucocorticoids and a control group.
• Correlation and multiple regression analyses were performed.
• A short-term oral 1,25-(OH)2D supplementation study was conducted.

Main Results:

• Glucocorticoid-treated asthmatic patients had approximately 50% lower serum OC levels compared to controls (P < 0.001).
• Serum OC directly correlated with 1,25-(OH)2D (r = 0.71; P < 0.001) and inversely with glucocorticoid dose in treated patients.
• Vitamin D supplementation increased OC levels in both steroid-treated and normal subjects, but to a lesser extent in the steroid group.

Conclusions:

• Long-term glucocorticoid therapy in asthma patients significantly depresses serum osteocalcin levels.
• This depression is likely due to reduced bone formation rates induced by glucocorticoids.
• Vitamin D supplementation may partially mitigate the effects of glucocorticoids on osteocalcin, but the response is blunted in steroid-treated individuals.