Table 5.

Multivariate logistic regression analysis (forward method) between UP and NDPM_2.5 ≥116 days/12 months, NDPM₁₀ ≥4.5 days/12 months, and other variables (P<0.1 in univariate logistic regression)

#Variables	Analysis C: multivariate logistic regression	P-value
	OR (95% CI)
Hemodialysis duration (years)	1.11 (1.08–1.15)	<0.001
Serum albumin (g/dL)	–	–
Log ferritin	1.72 (1.16–2.55)	0.007
LDL (mg/dL)	1.01 (1.00–1.01)	0.006
NDPM2.5 ≥116 days/12 months (yes)	3.57 (2.50–5.10)	<0.001
NDPM10 ≥4.5 days/12 months (yes)	–	–

Notes:

^#After adjustment for body mass index, DM, HBV, HCV, hemodiafiltration, Kt/V_urea, nPCR, nonanuria, corrected calcium, log iPTH, serum albumin, and NDPM₁₀ ≥4.5 days/12 months. ‘–’ represents not significance.

Abbreviations: UP, uremic pruritus; NDPM_2.5, the number of days of mean 24-hour PM_2.5 ≥35 μg/m³/12 months; NDPM₁₀, the number of days of mean 24-hour PM₁₀ ≥125 μg/m³/12 months; OR, odds ratio; CI, confidence interval; LDL, low-density lipoprotein; DM, diabetes mellitus; HBV, hepatitis B virus; HCV, hepatitis C virus; Kt/V_urea, dialysis clearance of urea; nPCR, normalized protein catabolic rate; iPTH, intact parathyroid hormone; PM_2.5, particulate matter with a diameter of <2.5 μm; PM₁₀, particulate matter with a diameter of <10 μm; log, logarithm.