TNFRSF11B and type 2 diabetes mellitus: The higher level of OPG had a higher risk of impaired glucose regulation (OR 1.108, 95 % CI 1.009–1.117, p = 0.01) after adjustment for sex, age, current smoking and alcohol intake, family history of diabetes, BMI, waist/hip ratio, HOMA-IR, triacylglycerol, total cholesterol, HDL- and LDL-cholesterol; the corresponding OR for both impaired glucose regulation and type 2 diabetes was 1.121 (95 % CI 1.101–1.141, p = 0.0005).