Table 4. Stratified analysis for association of homocysteine, folate and vitamin B12 with renal outcome.

Variable	Homocysteine (per log1 μmol/L)		Folate (per 5 nmol/L)		B12 (per 100 pg/ml)
	OR (95% CI) or β (SE)c	P	OR (95% CI) or β (SE)c	P	OR (95% CI) or β (SE)c	P
Incident CKDa
Men	2.02 (0.56 ~ 7.34)	0.285	0.69 (0.20 ~ 2.39)	0.555	1.12 (0.80 ~ 1.58)	0.504
Women	2.95 (1.30,6.73)	0.010	0.99 (0.65 ~ 1.52)	0.976	1.12 (0.95 ~ 1.32)	0.179
Age<60 years	3.26 (0.74 ~ 14.34)	0.118	0.69 (0.20 ~ 2.43)	0.567	1.34 (1.03 ~ 1.74)	0.030
Age≥60 years	2.21 (1.04 ~ 4.68)	0.039	1.00 (0.65 ~ 1.55)	0.998	1.02 (0.85 ~ 1.23)	0.830
Baseline SBP<160 mmHg	3.49 (0.81 ~ 15.09)	0.094	0.55 (0.23 ~ 1.32)	0.181	1.33 (1.07 ~ 1.65)	0.011
Baseline SBP≥160 mmHg	1.73 (0.77 ~ 3.88)	0.184	0.89 (0.54 ~ 1.48)	0.664	0.82 (0.61 ~ 1.12)	0.211
eGFR>90 ml/min/1.73 m2	0.66 (0.07 ~ 6.63)	0.726	1.21 (0.72 ~ 2.05)	0.466	1.11 (0.83 ~ 1.48)	0.482
eGFR 60 ~ 90 ml/min/1.73 m2	2.77 (1.33 ~ 5.77)	0.006	0.81 (0.50 ~ 1.31)	0.392	1.07 (0.89 ~ 1.28)	0.477
eGFR declineb
Men	−0.35 (0.22)	0.116	−0.15 (0.17)	0.358	0.04 (0.06)	0.440
Women	−0.57 (0.18)	0.001	0.05 (0.08)	0.499	−0.04 (0.04)	0.304
Age<60 years	−0.52 (0.19)	0.005	0.07 (0.11)	0.494	−0.08 (0.05)	0.101
Age≥60 years	−0.39 (0.20)	0.056	−0.05 (0.09)	0.631	0.03 (0.04)	0.438
Baseline SBP<160 mmHg	−0.40 (0.25)	0.103	0.03 (0.12)	0.835	−0.06 (0.05)	0.184
Baseline SBP≥160 mmHg	−0.47 (0.17)	0.005	0.02 (0.09)	0.782	0.02 (0.04)	0.555
eGFR>90 ml/min/1.73 m2	−0.29 (0.15)	0.048	−0.05 (0.07)	0.529	0.01 (0.03)	0.864
eGFR 60 ~ 90 ml/min/1.73 m2	−0.81 (0.29)	0.005	0.17 (0.15)	0.277	−0.05 (0.06)	0.358

Abbreviations: ACEIs, angiotensin converting enzyme inhibitors; ARBs, angiotensin II receptor blockers; CI, confidence interval; eGFR, estimated glomerular filtration rate; FA, folate; Hcy, homocysteine; HDL-C, high density lipoprotein cholesterol; SBP, systolic blood pressure.

^aIncident chronic kidney disease was defined as follow-up eGFR <60 ml/min/1.73 m² and eGFR decline rate >1 ml/min/1.73 m²/year.

^beGFR decline rate was calculated as the difference between the follow-up eGFR and baseline eGFR, which was divided by follow-up duration and expressed as ml/min/per 1.73 m²/year. Negative eGFR change indicates a fall in eGFR during follow-up.

^cHomocysteine, folate and vitamin B12 were all included in the multivariate model as continuous variables. Model was adjusted for age, gender, SBP, diabetes, smoking, cholesterol, HDL-C, triglycerides, body mass index, eGFR, previous use of ACEIs/ARBs, and SBP at the end of the follow-up.