DKK1 and osteoporosis: In addition, the serum DKK-1 levels correlated negatively with lumbar T score (r = −0.69, P < 0.001) (Figure 2) and with femur T score (r = −0.64, P < 0.001) (Figure 3), while there was no significant correlation between serum levels of either calcium, phosphorus, or alkaline phosphatase and both serum DKK-1 levels and the severity of osteoporosis as measured by T score (P > 0.05).