Table 4. Linear regression models for cystatin C-based estimated glomerular rate (eGFR) at age 60–64 years (ml/min/1.73 m², dependent variable) by cognitive function quartile at age 60–64 years (independent variable).

				Model 1				Model 2
Cognitive function quartile	n	n (%)	Mean (SD) eGFR(ml/min/1.73 m2)	Coeff	95% CI	PoverallA	P fortrendA	Coeff	95% CI	PoverallA	P fortrendA
Verbal memory	1313					<0.001	<0.001			0.21	0.10
1 (highest)		352 (26.8)	96.6	(ref)				(ref)
2		313 (23.8)	94.6	−2.1	−4.2, 0.0			−1.5	−3.6, 0.6
3		320 (24.4)	94.8	−2.1	−4.1, 0.0			−0.8	−2.9, 1.4
4 (lowest)		328 (25.0)	92.9	−4.1	−6.2, −2.0			−2.3	−4.6, 0.0
Letter search – speed	1320					0.50	0.13			0.91	0.50
1 (fastest)		294 (22.3)	95.5	(ref)				(ref)
2		359 (27.2)	94.8	−0.8	−2.9, 1.4			−0.5	−2.6, 1.6
3		359 (27.2)	94.5	−1.1	−3.2, 1.1			−0.5	−2.7, 1.6
4 (slowest)		308 (23.3)	94.1	−1.7	−3.9, 0.5			−0.8	−3.1, 1.4
Letter search – accuracy	1320					0.97	0.75			0.99	0.83
1 (highest)		350 (26.5)	95.0	(ref)				(ref)
2		353 (26.7)	94.6	−0.5	−2.5, 1.6			−0.1	−2.2, 1.9
3		314 (23.8)	94.6	−0.4	−2.6, 1.7			−0.1	−2.2, 2.0
4 (lowest)		303 (23.0)	94.7	−0.4	−2.5, 1.8			0.3	−1.9, 2.4
Simple reaction time	1308					0.003	0.002			0.03	0.02
1 (fastest)		328 (25.1)	97.3	(ref)				(ref)
2		334 (25.5)	94.2	−3.1	−5.2, −1.0			−2.7	−4.8, −0.6
3		337 (25.8)	94.7	−2.4	−4.5, −0.4			−2.0	−4.1, 0.1
4 (slowest)		309 (23.6)	93.4	−3.8	−5.9, −1.7			−2.9	−5.1, −0.8
Choice reaction time	1306					0.02	0.004			0.11	0.06
1 (fastest)		347 (26.6)	96.7	(ref)				(ref)
2		319 (24.4)	95.8	−1.1	−3.1, 1.0			−0.8	−2.9, 1.2
3		340 (26.0)	93.4	−2.9	−5.0, −0.9			−2.5	−4.5, −0.4
4 (slowest)		300 (23.0)	93.7	−2.6	−4.7, −0.5			−1.5	−3.7, 0.7

^ALikelihood ratio test.

Model 1: Adjusted for sex and age at cystatin C measurement.

Model 2: Additionally adjusted for socioeconomic position at age 53 years and highest educational attainment.