CYP27A1 and osteoporosis: Compared with the non-SFG group, binary logistic regression analysis revealed that BMI (OR = 0.825, 95% CI 0.720–0.945) and femoral neck BMD measured by DEXA (OR = 0.067, 95% CI 0.012–0.385) were protective factors, and elevated serum CTX levels (OR = 6.089, 95% CI 1.735–21.375) was a risk factor for subsequent fractures within 2 years in patients with osteoporosis (Table 3).