Journal of Diabetes Research

Research Article

Adherence to General Diabetes and Foot Care Processes, with Prompt Referral, Are Associated with Amputation-Free Survival in People with Type 2 Diabetes and Foot Ulcers: A Scottish National Registry Analysis

Table 2

Frequencies and univariate hazard ratios for amputation-free survival (LEA/death) in people with type 2 diabetes and DFU in Scotland.


Variable	Category	All ages				≤70				>70
Variable	Category	No LEA	LEA	Univariate HR (95% CI)		No LEA	LEA	Univariate HR (95% CI)		No LEA	LEA	Univariate HR (95% CI)

Age	Continuous	64.99 (12.34)	74.76 (10.86)	1.06 (1.05-1.06)	<0.001	57.32 (8.87)	61.2 (7.49)	1.05 (1.04-1.07)	<0.001	77.31 (4.94)	80.43 (5.91)	1.07 (1.06-1.07)	<0.001

Gender	Female (R.C.)	1689 (36.7)	913 (40.7)	1.00 (-)		871 (30.7)	226 (34.2)	1.00 (-)		818 (46.3)	687 (43.4)	1.00 (-)
Gender	Male	2913 (63.3)	1330 (59.3)	0.90 (0.83-0.98)	0.015	1964 (69.3)	435 (65.8)	0.88 (0.75-1.04)	0.139	949 (53.7)	895 (56.6)	1.12 (1.02-1.24)	0.023

SIMD score	≥4 (R.C.)	2560 (55.6)	1269 (56.6)	1.00 (-)		1462 (51.6)	309 (46.7)	1.00 (-)		1098 (62.1)	960 (60.7)	1.00 (-)
	<3	1848 (40.2)	868 (38.7)	0.98 (0.90-1.07)	0.71	1247 (44.0)	321 (48.6)	1.23 (1.05-1.44)	<0.01	601 (34.0)	547 (34.6)	1.05 (0.94-1.16)	0.379
	Missing	194 (4.2)	106 (4.7)	1.03 (0.85-1.26)	0.755	126 (4.4)	31 (4.7)	1.08 (0.74-1.56)	0.702	68 (3.8)	75 (4.7)	1.14 (0.90-1.44)	0.277

Smoker	Past/never (R.C.)	3872 (84.1)	1863 (83.1)	1.00 (-)		2263 (79.8)	456 (69.0)	1.00 (-)		1609 (91.1)	1407 (88.9)	1.00 (-)
Smoker	Current	730 (15.9)	380 (16.9)	1.10 (0.98-1.22)	0.107	572 (20.2)	205 (31.0)	1.70 (1.44-2.01)	<0.001	158 (8.9)	175 (11.1)	1.21 (1.04-1.42)	0.019

BMI	≥25 (R.C.)	611 (13.3)	550 (24.5)	1.00 (-)		278 (9.8)	95 (14.4)	1.00 (-)		333 (18.8)	455 (28.8)	1.00 (-)
	<25	3717 (80.8)	1587 (70.8)	0.59 (0.53-0.65)	<0.001	2347 (82.8)	525 (79.4)	0.74 (0.59-0.92)	<0.01	1370 (77.5)	1062 (67.1)	0.69 (0.62-0.77)	<0.001
	Missing	274 (6.0)	106 (4.7)	0.55 (0.44-0.67)	<0.001	210 (7.4)	41 (6.2)	0.64 (0.45-0.93)	0.015	64 (3.6)	65 (4.1)	0.89 (0.68-1.15)	0.355

eGFR	>59 (R.C.)	3073 (66.8)	1038 (46.3)	1.00 (-)		2151 (75.9)	392 (59.3)	1.00 (-)		922 (52.2)	646 (40.8)	1.00 (-)
	≤59	1054 (22.9)	1007 (44.9)	2.20 (2.01-2.40)	<0.001	384 (13.5)	196 (29.7)	2.38 (2.00-2.82)	<0.001	670 (37.9)	811 (51.3)	1.47 (1.32-1.63)	<0.001
	Missing	475 (10.3)	198 (8.8)	1.13 (0.97-1.32)	0.112	300 (10.6)	73 (11.0)	1.18 (0.92-1.52)	0.192	175 (9.9)	125 (7.9)	1.03 (0.85-1.25)	0.766

Total cholesterol	≤5 mmol (R.C.)	3430 (74.5)	1793 (79.9)	1.00 (-)		1968 (69.4)	482 (72.9)	1.00 (-)		1462 (82.7)	1311 (82.9)	1.00 (-)
	>5 mmol	1143 (24.8)	433 (19.3)	0.82 (0.73-0.91)	<0.001	849 (29.9)	174 (26.3)	0.90 (0.76-1.08)	0.251	294 (16.6)	259 (16.4)	1.05 (0.91-1.19)	0.52
	Missing	29 (0.6)	17 (0.8)	1.30 (0.80-2.09)	0.308	18 (0.6)	5 (0.8)	1.35 (0.56-3.25)	0.528	11 (0.6)	12 (0.8)	1.33 (0.75-2.35)	0.347

Peripheral vasc. disease	No (R.C.)	4164 (90.5)	1936 (86.3)	1.00 (-)		2582 (91.1)	546 (82.6)	1.00 (-)		1582 (89.5)	1390 (87.9)	1.00 (-)
Peripheral vasc. disease	Yes	438 (9.5)	307 (13.7)	1.26 (1.12-1.43)	<0.001	253 (8.9)	115 (17.4)	1.81 (1.48-2.21)	<0.001	185 (10.5)	192 (12.1)	1.02 (0.87-1.18)	0.839

Claudication	No	4064 (88.3)	1955 (87.2)	1.00 (-)		2477 (87.4)	577 (87.3)	1.00 (-)		1587 (89.8)	1378 (87.1)	1.00 (-)
Claudication	Yes	210 (4.6)	98 (4.4)	1.05 (0.85-1.28)	0.672	134 (4.7)	34 (5.1)	1.19 (0.84-1.69)	0.331	76 (4.3)	64 (4.0)	1.01 (0.79-1.30)	0.941
	Missing	328 (7.1)	190 (8.5)	1.18 (1.01-1.37)	0.036	224 (7.9)	50 (7.6)	0.99 (0.74-1.32)	0.93	104 (5.9)	140 (8.8)	1.33 (1.11-1.58)	<0.01

AMI	No (R.C.)	4182 (90.9)	1897 (84.6)	1.00 (-)		2588 (91.3)	540 (81.7)	1.00 (-)		1594 (90.2)	1357 (85.8)	1.00 (-)
AMI	Yes	420 (9.1)	346 (15.4)	1.57 (1.40-1.76)	<0.001	247 (8.7)	121 (18.3)	2.03 (1.66-2.47)	<0.001	173 (9.8)	225 (14.2)	1.35 (1.17-1.55)	<0.001

CVD	No(R.C.)	4281 (93.0)	1992 (88.8)	1.00 (-)		2671 (94.2)	587 (88.8)	1.00 (-)		1610 (91.1)	1405 (88.8)	1.00 (-)
CVD	Yes	321 (7.0)	251 (11.2)	1.49 (1.31-1.70)	<0.001	164 (5.8)	74 (11.2)	1.93 (1.52-2.46)	<0.001	157 (8.9)	177 (11.2)	1.16 (0.99-1.36)	0.069

Hypertension treatment	No (R.C.)	1330 (28.9)	540 (24.1)	1.00 (-)		844 (29.8)	154 (23.3)	1.00 (-)		486 (27.5)	386 (24.4)	1.00 (-)
	Yes	3221 (70.0)	1683 (75.0)	1.23 (1.12-1.35)	<0.001	1950 (68.8)	499 (75.5)	1.31 (1.09-1.57)	<0.01	1271 (71.9)	1184 (74.8)	1.17 (1.05-1.32)	<0.01
	Missing	51 (1.1)	20 (0.9)	1.13 (0.72-1.76)	0.602	41 (1.4)	8 (1.2)	1.18 (0.58-2.40)	0.658	10 (0.6)	12 (0.8)	1.64 (0.92-2.92)	0.116

Retinopathy	No (R.C.)	2541 (55.2)	1280 (57.1)	1.00 (-)		1376 (48.5)	338 (51.1)	1.00 (-)		1165 (65.9)	942 (59.5)	1.00 (-)
	Yes	1961 (42.6)	879 (39.2)	0.90 (0.82-0.98)	0.011	1383 (48.8)	296 (44.8)	0.87 (0.74-1.02)	0.082	578 (32.7)	583 (36.9)	1.13 (1.02-1.25)	0.02
	Missing	100 (2.2)	84 (3.7)	1.62 (1.30-2.02)	<0.001	76 (2.7)	27 (4.1)	1.56 (1.05-2.31)	0.037	24 (1.4)	57 (3.6)	1.98 (1.52-2.59)	<0.001

Nine care processes before DFU	<9 (R.C.)	1940 (42.2)	1105 (49.3)	1.00 (-)		1209 (42.6)	305 (46.1)	1.00 (-)		731 (41.4)	800 (50.6)	1.00 (-)
Nine care processes before DFU	9	2662 (57.8)	1138 (50.7)	0.66 (0.61-0.72)	<0.001	1626 (57.4)	356 (53.9)	0.75 (0.65-0.88)	<0.001	1036 (58.6)	782 (49.4)	0.61 (0.56-0.68)	<0.001

Foot care visits before DFU	No (R.C.)	3386 (73.6)	1726 (77.0)	1.00 (-)		2089 (73.7)	496 (75.0)	1.00 (-)		1297 (73.4)	1230 (77.7)	1.00 (-)
Foot care visits before DFU	Yes	1216 (26.4)	517 (23.0)	0.88 (0.80-0.97)	<0.01	746 (26.3)	165 (25.0)	0.99 (0.83-1.18)	0.88	470 (26.6)	352 (22.3)	0.83 (0.74-0.94)	<0.01

wks	≤12 wks (R.C.)	3477 (75.6)	1764 (78.6)	1.00 (-)		2151 (75.9)	549 (83.1)	1.00 (-)		1326 (75.0)	1215 (76.8)	1.00 (-)
wks	>12 wks	1125 (24.4)	479 (21.4)	0.93 (0.84-1.03)	0.171	684 (24.1)	112 (16.9)	0.71 (0.58-0.87)	<0.001	441 (25.0)	367 (23.2)	1.01 (0.90-1.13)	0.885

Foot care quality after DFU	Low	2181 (47.4)	865 (38.6)	1.00 (-)		1310 (46.2)	222 (33.6)	1.00 (-)		871 (49.3)	643 (40.6)	1.00 (-)
Foot care quality after DFU	High	2421 (52.6)	1378 (61.4)	1.82 (1.67-1.98)	<0.001	1525 (53.8)	439 (66.4)	2.11 (1.79-2.48)	<0.001	896 (50.7)	939 (59.4)	1.84 (1.66-2.04)	<0.001

Foot care checks after DFU	No (R.C.)	941 (20.4)	382 (17.0)	1.00 (-)		572 (20.2)	104 (15.7)	1.00 (-)		369 (20.9)	278 (17.6)	1.00 (-)
Foot care checks after DFU	Yes	3661 (79.6)	1861 (83.0)	1.95 (1.75-2.18)	<0.001	2263 (79.8)	557 (84.3)	2.06 (1.67-2.54)	<0.001	1398 (79.1)	1304 (82.4)	2.00 (1.75-2.28)	<0.001

CV visits after DFU	0 (R.C.)	2858 (62.1)	1539 (68.6)	1.00 (-)		1565 (55.2)	355 (53.7)	1.00 (-)		1293 (73.2)	1184 (74.8)	1.00 (-)
CV visits after DFU	≥1	1744 (37.9)	704 (31.4)	0.79 (0.73-0.87)	<0.001	1270 (44.8)	306 (46.3)	1.03 (0.89-1.20)	0.682	474 (26.8)	398 (25.2)	0.97 (0.86-1.09)	0.581

CV care quality after DFU	Low (R.C.)	3887 (84.5)	1957 (87.2)	1.00 (-)		2284 (80.6)	531 (80.3)	1.00 (-)		1603 (90.7)	1426 (90.1)	1.00 (-)
CV care quality after DFU	High	715 (15.5)	286 (12.8)	0.87 (0.77-0.99)	0.026	551 (19.4)	130 (19.7)	1.06 (0.87-1.28)	0.56	164 (9.3)	156 (9.9)	1.10 (0.94-1.30)	0.247

Minor LEA	No (R.C.)	4398 (95.6)	2127 (94.8)	1.00 (-)		2681 (94.6)	596 (90.2)	1.00 (-)		1717 (97.2)	1531 (96.8)	1.00 (-)
Minor LEA	Yes	204 (4.4)	116 (5.2)	0.85 (0.71-1.03)	0.083	154 (5.4)	65 (9.8)	1.31 (1.01-1.69)	0.046	50 (2.8)	51 (3.2)	0.78 (0.59-1.04)	0.074