Table 4. Univariable and Multivariable-Adjusted Regression Analyses of Correlation between Normalized Whole-Brain GMV and TMT Scores in Participants Stratified by eGFR (<45 vs. ≥45 mL/min/1.73 m²).

Model I: Multivariable analysis adjusted for sex and age. Model II: Model I + diabetes mellitus, estimated glomerular filtration rate, and education. Model III: Model II + systolic blood pressure, smoking habits, drinking habits, hemoglobin, previous history of cardiovascular disease, and log-transformed urinary protein to creatinine ratio. Abbreviations: eGFR, estimated glomerular filtration rate; TMT, Trail Making Test.

		TMT-A		TMT-B		ΔTMT
		eGFR <45 mL/min/1.73 m2 (n = 61)	eGFR ≥45 mL/min/1.73 m2 (n = 34)	eGFR <45 mL/min/1.73 m2 (n = 61)	eGFR ≥45 mL/min/1.73 m2 (n = 34)	eGFR <45 mL/min/1.73 m2 (n = 61)	eGFR ≥45 mL/min/1.73 m2 (n = 34)
Univariable analysis	Standardized β	- 0.549	- 0.368	- 0.576	- 0.375	- 0.537	- 0.332
	P	<0.001	0.032	<0.001	0.029	<0.001	0.055
	P for interaction	0.569		0.401		0.401
Model I	Standardized β	- 0.477	- 0.477	- 0.512	- 0.460	- 0.482	- 0.398
	P	<0.001	0.068	<0.001	0.079	<0.001	0.134
	P for interaction	0.383		0.244		0.244
Model II	Standardized β	- 0.448	- 0.280	- 0.514	- 0.106	- 0.495	- 0.026
	P	0.002	0.325	<0.001	0.672	<0.001	0.917
	P for interaction	0.537		0.358		0.358
Model III	Standardized β	- 0.407	- 0.200	- 0.472	- 0.011	- 0.456	0.063
	P	0.016	0.557	0.003	0.968	0.005	0.827
	P for interaction	0.574		0.400		0.401