Non-traumatic lower limb amputation in patients with end-stage renal failure on dialysis: an Australian perspective

Figures & data

Table 1. Baseline characteristics.

N	218
Age (years)	60.73 ± 14.48
Male	109 (50%)
Indigenous	113 (51.8%)
HD	159 (72.9%)
DM	142 (65.1%)
Type I	5 (3.5%)
Cause of ESRF
Diabetes Mellitus	101 (46.3%)
Hypertension	26 (11.9%)
Other/unknown	91 (41.8%)
Ulceration	54 (24.8%)
PAD	67 (30.7%)
Retinopathy	64 (29.4%)
Neuropathy	61 (28%)
Foot deformity	11 (5%)
IHD	108 (49.5%)
CVE	35 (16.1%)
HPTN	203 (93.1%)
Dyslipidemia	168 (77.1%)
Amputation	29 (13.3%)

Notes: Continuous variable expressed as mean ± SD, nominal variable expressed as n (%).

Table 2. Characteristics of group of patients with non-traumatic LLA.

N	29
Male	16 (55.2%)
Indigenous	22 (75.9%)
Diabetic nephropathy as cause of ESRF	24 (82.8%)
Diabetes Mellitus	29 (100%)
Type I	1 (3.4%)
Major amputation	9 (31%)
Previous multiple minor amputations	3 (33.33%)
Ulceration	27 (93.1%)
Neuro-ischemic ulcers	12 (44.4%)
Ischemic heart disease	17 (58.6%)
Cerebrovascular event	6 (20.7%)
Peripheral arterial disease	26 (89.7%)
Retinopathy	19 (65.5%)
Neuropathy	24 (82.8%)
Foot deformity	8 (27.6%)
Hypertension	27 (93.1%)
Dyslipidemia	27 (93.1%)

Note: Nominal variables expressed as n (%).

Table 3. Demographic and comorbid risk factors for LLA.

Association	OR [95%CI]	Pearson’s ChiSquared withcontinuity correction
Ulceration	81 [18.20–360.48]	<0.001
PAD	31.29 [9.02–108.56]	<0.001
Neuropathy	19.72 [7.05–55.14]	<0.001
Dyslipidemia	4.6 [1.05–20.05]	0.049
Indigenous	3.39 [1.38–8.33]	0.01
Male	1.3 [0.59–2.85]	0.651
DM present	1.67 [1.49–1.88]	<0.001
HD	1.49 [0.58–3.87]	0.545
IHD	1.53 [0.69–3.37]	0.395
CVE	1.44 [0.54–3.84]	0.647
Retinopathy	6.08 [2.64–14.02]	<0.001
Foot deformity	23.62 [5.82–95.93]	<0.001
HPTN	0.99 [0.21–4.67]	1

Table 4. Multivariate analysis—binary logistic regression for demographic and comorbid risk factors.

Association	B	S.E.	Significance	OR	Lower	Higher
Ulceration	2.52	0.88	0.004	12.41	2.23	69.04
PAD	2.005	0.87	0.02	7.43	1.36	40.45
Retinopathy	0.62	0.64	0.337	1.85	0.53	6.52
Neuropathy	0.97	0.73	0.182	2.64	0.64	10.99
Foot deformity	2.02	1.01	0.045	7.51	1.05	53.86
Dyslipidemia	1.57	1.16	0.175	4.808	0.49	46.39
Indigenous	1.61	0.69	0.019	4.98	1.3	19.23
Constant	−1.62	1.03	2.46	0.117	0.2

Table 5. Biochemical risk factors.

Association	Amputees	Non-amputees	Significantvalue
Vitamin D	44.11 ± 17.07	65.45 ± 33.64	0.037
Calcium	2.04 ± 0.41	2.08 ± 0.41	0.579
Corrected calcium	2.25 ± 0.45	2.22 ± 0.43	0.761
Phosphate	1.64 ± 0.32	1.63 ± 1.58	0.894
Albumin	29.32 ± 4.70	32.81 ± 4.00	<0.001
Cholesterol	3.93 ± 0.93	4.04 ± 1.09	0.626
Triglycerides	1.72 ± 1.33	1.98 ± 1.24	0.295
HDL	0.70 ± 0.43	0.84 ± 0.43	0.095
Hemoglobin	104.32 ± 10.13	108.53 ± 10.07	0.041
Hematocrit	0.32 ± 0.03	0.48 ± 1.96	0.673
Urea	18.42 ± 5.26	19.83 ± 5.48	0.195
Creatinine	573.90 ± 226.58	626.83 ± 212.38	0.224
Parathyroid hormone	46.72 (5.10–121.78)	47.64 (0.60–263.89)	0.291
C-reactive protein	59.75 (0.00–133.48)	36.49 (0.00–257.00)	0.008
Bilirubin	10.48 (6.17–27.64)	10.75 (4.00–43.32)	0.680
Direct bilirubin	4.44 (4.00–14.86)	4.00 (4.00–27.80)	0.116
LDL	2.08 (0.99–3.80)	2.00 (0.60–4.42)	0.401
HbA1c	7.10 (5.17–9.22)	5.72 (3.90–10.80)	<0.001

Note: Values expressed as mean ± SD or median (interquartile range).

Table 6. Multivariate analysis—binary logistic regression of biochemical risk factors.

Association	B	S.E.	Significance	OR	Lower	Higher
Vitamin D	−0.024	0.027	0.373	0.976	0.926	1.029
Albumin	−0.405	0.186	0.030	0.667	0.463	0.961
C-reactive protein	−0.003	0.015	0.853	0.997	0.969	1.026
Hemoglobin	−0.090	0.067	0.183	0.914	0.801	1.043
HbA1c	1.078	0.397	0.007	2.940	1.349	6.406
Constant	13.926	8.552	0.103	1117069.32