Associations between bone-alkaline phosphatase and bone mineral density in adults with and without diabetes

Insufficient evidence is available to reliably compare the roles of bone alkaline phosphatase (BAP) and bone mineral density (BMD) in diabetes. This study aimed to compare associations between BAP and BMD in adults with and without diabetes to elucidate fracture risk in diabetes. Data were extracted from the National Health and Nutrition Examination Survey (NHANES), 2001–2004, including 4197 adults aged 20 to 49 years, 143 with diabetes (DM group), and 4054 without (non-DM group). Main outcome measure was BMD and regression analyses were performed to identify serum BAP and other covariates associated with total BMD. BMD decreased significantly in DM patients when BAP was increased. In the non-DM group, all BMD results were significantly decreased when BAP was increased. Factors associated with total BMD varied with DM status. Lifestyle measures such as smoking and physical activity were also associated with BMD in the non-DM group. BAP and BMD are inversely associated in DM and non-DM patients. BAP is significantly associated with BMD after controlling for other variables, suggesting that BAP may interact with other factors altering bone metabolism in DM patients.