Although recent studies have linked serum osteocalcin to bone and energy metabolism, researchers in Korea found that it is not linked to the development of type 2 diabetes, according to data published in Diabetes Care.
Researchers conducted a retrospective cohort study of 1,229 men aged 25 to 60 years without diabetes who attended the Health Promotion Center at Samsung Medical Center in Seoul, Korea between January 1997 and December 1997.
Osteocalcin levels were separated into three tertiles: bottom (n=400; 0.83 nmol/L), middle (n=406; 1.28 nmol/L) and top (n=423; 1.83 nmol/L).
The patients were followed on an outpatient basis and during hospitalization for an average of 8.4 years. At baseline, the researchers report that serum total osteocalcin levels were linked with positive metabolic profiles.
“BMI, body fat percentage, and triglyceride levels varied inversely with the osteocalcin tertiles (all P<.01), and serum HDL cholesterol levels increased with the osteocalcin tertiles (P=.014),” they wrote.
According to data, incident type 2 diabetes developed in 7.3% of the study population and 13% of the 607 impaired fasting glucose (IFG) patients during the 8.4 years of follow-up.
You-Cheol Hwang, MD, PhD, from the department of medicine in the division of endocrinology and metabolism at Kyung Hee University Hospital at Gangdong in Seoul, Korea, and colleagues wrote that levels of HOMA-IR decreased progressively from bottom to top osteocalcin tertiles, but no differences were apparent in fasting plasma glucose (FPG) and HbA1c levels across the osteocalcin tertiles.
“Instead, serum osteocalcin levels were significantly correlated with FPG (P=.041) and HbA1c levels (P=.033) in 103 patients with diabetes at baseline. Therefore, it appears that serum osteocalcin is more closely associated with the parameters reflecting insulin resistance including obesity, atherogenic dyslipidemia, and inflammation rather than glucose tolerance itself before the onset of diabetes,” Hwang and colleagues wrote.
They concluded that serum osteocalcin levels are not associated with the development of type 2 diabetes in middle-aged Korean men. They suggest that further prospective studies be conducted to understand the role of undercarboxylated osteocalcin on the development of diabetes.
Disclosure: The researchers report no relevant financial disclosures.