TABLE 2.

Threshold effect analyses of the relationship between eGFR and MMSE using two piecewise regression models.

eGFR, ml/min/1.73 m2	Subjects	MMSE Mean ± SD	Crude model β (95% CI)	P-value	Adjusted model β (95% CI)	P-value
Per 10 ml/min/1.73 m2 increase	9,527	22.1 ± 6.4	0.38 (0.32, 0.45)	<0.001	−0.04 (−0.10, 0.01)	0.122
Turning point
<71.52	1,919	21.2 ± 6.7	0.50 (0.30, 0.71)	<0.001	0.27 (0.12, 0.41)	<0.001
≥ 71.52	7,608	22.3 ± 6.3	0.59 (0.46, 0.72)	<0.001	−0.28 (−0.39, −0.17)	<0.001
P for log-likelihood ratio test				0.461		<0.001

eGFR, estimated glomerular filtration rate; MMSE, Mini-Mental State Examination.

Adjusted for: sex, age, body mass index, systolic blood pressure, diastolic blood pressure, education, coronary heart disease, diabetes mellitus, smoking status, alcohol consumption, homocysteine, total cholesterol, triglycerides, high-density lipoprotein, and antihypertensive drugs.