Table 7.

Analysis of DSPN risk factors for confounding bias in data multi-model control after PSM.

Variables	Model 1		Model 2		Model 3		Model 4
	OR (95% CI)	P	OR (95% CI)	P	OR (95% CI)	P	OR (95% CI)	P
25(OH)D, ng/mL	0.70 (0.64–0.76)	<0.001	0.69 (0.63–0.75)	<0.001	0.68 (0.63–0.75)	<0.001	0.67 (0.61–0.74)	<0.001

Model 1 was unadjusted. Model 2 was adjusted for age, BMI, and gender. Model 3 was adjusted for age, BMI, gender, smoke, and exercise. Model 4 was adjusted for age, BMI, gender, exercise, smoke, SBP, DBP, DM duration, TG, TC, HbA1c, and IR. 25(OH)D, 25-hydroxyvitamin D; DSPN, distal symmetric polyneuropathy; OR, odds ratio; CI, confidence interval; PSM, propensity score matching; BMI, body mass index; SBP, systolic blood pressure; DBP, diastolic blood pressure; DM, diabetes mellitus; TG, triglycerides; TC, total cholesterol; HbA1c, glycated hemoglobin; IR, insulin resistance.