TABLE 5.

Threshold effect analysis of total cholesterol on lumbar BMD using the two-piecewise linear regression model.

Lumbar BMD	Adjusted β (95% CI) P
Fitting by the standard linear model	−0.022 (−0.028, −0.015) <0.0001
Fitting by the two-piecewise linear model
Inflection point	6.077
Total cholesterol <6.077 (mmol/L)	−0.018 (−0.027, −0.010) <0.0001
Total cholesterol >6.077 (mmol/L)	−0.033 (−0.055, −0.012) 0.0019
Log likelihood ratio	0.243

Gender, age, race, marital status, alanine aminotransferase, albumin, alkaline phosphatase, bicarbonate, blood urea nitrogen, chloride, creatinine, globulin, glucose, gamma glutamyl transferase, iron, osmolality, phosphorus, sodium, total bilirubin, total calcium, triglycerides, total protein, uric acid were adjusted.