Serum osteoprotegerin level is positively associated with peripheral artery disease in patients with peritoneal dialysis

Figures & data

Table 1. Clinical variable of the 70 PD patients in the normal or low ABI group.

Characteristic	All participants	Normal ABI group	Low ABI group	p Value
	(n = 70)	(n = 57)	(n = 13)
Age (years)	56.41 ± 15.30	56.21 ± 15.59	57.31 ± 14.53	.817
Peritoneal dialysis duration (months)	53.76 ± 42.06	54.30 ± 37.07	51.38 ± 61.24	.824
Female, n (%)	41 (58.6)	31 (54.4)	10 (76.9)	.137
Diabetes, n (%)	26 (37.1)	18 (31.6)	8 (61.5)	.044*
Hypertension, n (%)	44 (62.9)	38 (66.7)	6 (46.2)	.167
CAPD model, n (%)	51 (72.9)	43 (75.4)	8 (61.5)	.309
Smoking, n (%)	9 (12.9)	6 (10.5)	3 (23.1)	.222
ACEi/ARB, n (%)	32 (45.7)	29 (50.9)	3 (23.1)	.132
CCB, n (%)	30 (42.9)	27 (47.4)	3 (23.1)	.198
Beta blocker, n (%)	28 (40)	23 (40.4)	5 (38.5)	.851
statin, n (%)	17 (24.3)	13 (22.8)	4 (30.8)	.806
insulin, n (%)	11 (42.3)	8 (44.4)	3 (37.5)	.921
OHA, n (%)	14 (53.8)	10 (55.6)	4 (50)	.870
Body mass index (kg/m^2)	24.50 ± 4.27	24.40 ± 3.81	24.94 ± 6.07	.683
Left ankle-brachial index	1.07 ± 0.17	1.13 ± 0.13	0.84 ± 0.13	<.001*
Right ankle-brachial index	1.08 ± 0.15	1.13 ± 0.12	0.87 ± 0.10	<.001*
Systolic blood pressure (mmHg)	144.11 ± 24.49	144.93 ± 22.64	140.54 ± 32.26	.563
Diastolic blood pressure (mmHg)	84.90 ± 12.99	85.33 ± 11.98	83.00 ± 17.17	.563
Albumin (mg/dL)	3.73 ± 0.37	3.74 ± 0.39	3.67 ± 0.28	.543
Total cholesterol (mg/dL)	171.41 ± 38.21	174.07 ± 39.46	159.77 ± 30.80	.226
Triglyceride (mg/dL)	147.00 (100.50–226.50)	150.00 (93.50–222.50)	131.00 (114.00–236.50)	.892
Fasting glucose (mg/dL)	106.00 (95.75–137.25)	104.00 (95.00–127.00)	122.00 (101.50–149.50)	.123
Blood urea nitrogen (mg/dL)	59.56 ± 18.61	60.16 ± 19.62	56.92 ± 13.61	.575
Creatinine (mg/dL)	11.17 ± 3.00	11.59 ± 2.86	9.34 ± 2.98	.013*
Total calcium (mg/dL)	9.15 ± 0.79	9.23 ± 0.79	8.80 ± 0.72	.078
Phosphorus (mg/dL)	5.16 ± 1.35	5.18 ± 1.37	5.12 ± 1.32	.886
Intact parathyroid hormone (pg/mL)	247.16 (91.40–534.35)	213.62 (81.93–507.16)	313.60 (201.70–576.10)	.283
C-reactive protein (mg/dL)	0.27 (0.07–0.96)	0.19 (0.06–0.42)	1.46 (0.81–1.75)	<.001*
Osteoprotegerin (pg/mL)	182.91 ± 77.08	162.36 ± 55.17	273.03 ± 95.66	<.001*
Weekly Kt/V	2.09 ± 0.40	2.11 ± 0.40	1.98 ± 0.36	.276
Peritoneal Kt/V	1.80 ± 0.44	1.85 ± 0.42	1.58 ± 0.46	.048*
Total clearance of creatinine (L/week)	57.32 ± 23.46	57.29 ± 25.33	57.43 ± 13.04	.985
Peritoneal clearance of creatinine (L/week)	42.42 ± 15.87	43.13 ± 15.74	39.30 ± 16.72	.437

Continuous variables are reported as mean ± standard deviation or median and interquartile range and compared with a t-test Mann–Whitney U-test, as appropriate. Categorical variables are reported as number (%) compared with the chi-square test. ABI: ankle-brachial index; CAPD: continuous ambulatory peritoneal dialysis; Weekly Kt/V: weekly fractional clearance index for urea.

*p < .05 was considered statistically significant.

Figure 1. Receiver operating characteristic (ROC) curve analysis to predict PAD of 70 PD patients. The area under the ROC curve (AUC) indicates the diagnostic power of OPG at predicting PAD of PD patients.

Table 2. Risk factors for the development of PAD of PD patients.

Variables	Adjusted odds ratio	95% confidence interval	p Value
Osteoprotegerin (pg/mL) (each increase of 1 pg/mL)	1.027	1.010–1.045	.002*
Log-CRP	1.102	1.006–1.207	.037*

Analysis was done using the multivariable logistic regression analysis adjusted for DM, CRP, peritoneal Kt/V, creatinine, and OPG. CRP was log-transformed due to skew distribution. CRP C-reactive protein, Peritoneal Kt/V, weekly fractional clearance index for urea.

* p < .05 was considered statistically significant.