Lower Limb Arterial Ischemia: An Independent Risk Factor of Sudomotor Dysfunction in Type 2 Diabetes

Figures & data

Table 1 Primary Characteristics of Patients with and without Sudomotor Dysfunction

	Without Sudomotor Dysfunction (n=127)	With Sudomotor Dysfunction (n=384)	P
Sex (F/M) (n)	83/44	237/147	0.603
Age (years)	56 (48–64)	62 (54–70)	<0.001*
BMI (kg/m^2)	24.87 ± 3.65	24.20 ± 3.30	0.068
Duration of diabetes (years)	8 (2–12)	10 (5–17)	0.001*
Systolic pressure (mmHg)	137 ± 18	134 ± 19	0.092
Diastolic pressure (mmHg)	82 ± 13	77 ± 12	0.001*
HbA1c (%)	9.43 ± 2.32	9.18 ± 2.47	0.293
TSH (mIU/L)	1.87 (1.20–2.68)	1.97 (1.38–2.85)	0.143
TC (mmol/L)	4.26 (3.75–5.01)	4.14 (3.41–5.07)	0.592
TG (mmol/L)	1.63 (1.12–2.39)	1.37 (0.95–2.14)	0.054
LDL (mmol/L)	2.65 (2.07–3.23)	2.45 (1.82–3.17)	0.423
HDL (mmol/L)	1.06 (0.88–1.28)	1.05 (0.88–1.27)	0.784
Scr (umol/L)	64 (52–76)	72 (58–90)	<0.001*
eGFR (mL/min/1.73m^2)	114.20 (93.73–129.38)	93.17 (70.86–113.98)	<0.001*
ACR (mg/g)	19.7 (12.4–67.7)	25.6 (11.7–86.6)	0.715
Lower limb arterial ischemia (%)	36.2%	51.2%	0.004*
Hypertension (%)	55.1%	60.5%	0.288
Alcohol consumption (%)	39.4%	41.9%	0.540
Smoking (%)	23.0%	21.4%	0.633

Notes: “*” of P is less than 0.05. Data are mean ± SD, %, or median (interquartile range).

Abbreviations: BMI, body mass index; HbA1c, glycosylated hemoglobin; TSH, thyroid-stimulating hormone; TC, total cholesterol; TG, triglyceride; LDL, low-density lipoprotein; HDL, high-density lipoprotein; Scr, serum creatinine; eGFR, estimated glomerular filtration rate; ACR, albumin-creatinine ratio.

Table 2 Comparison of Subjects Without vs with Lower Limb Arterial Ischemia

	Non- Lower Limb Arterial Ischemia (n=269)	Lower Limb Arterial Ischemia (n=242)	P
ABI	1.19 ± 0.08	1.16 ± 0.10	<0.001*
TBI	0.86 ± 0.09	0.70 ± 0.12	<0.001*
TcPO2	56 ± 10	47 ± 13	<0.001*
Slop4	10.42 ± 5.32	8.08 ± 4.84	<0.001*
Sudomotor dysfunction	69.9%	80.9%	0.004*

Notes: “*” of P is less than 0.05. Data are mean ± SD or %.

Abbreviations: ABI, ankle brachial index; TBI, toe brachial index; TcPO2, transcutaneous oxygen tension; Slop4, the slope of the chromatic aberration curve in the first 4 minutes.

Table 3 Sudomotor Function Data in the Different Types of Arterial Ischemia

	ABI		p	TBI		p	TcPO2		p
	Normal ABI	Low ABI		Normal TBI	Low TBI		Normal TcPO2	Low TcPO2
N (%)	501 (98.5%)	7 (1.5%)		319 (80.0%)	191 (20.0%)		390 (81.8%)	89 (18.2%)
Slop4	7.76 ± 5.18	5.68 ± 2.58	0.010*	9.94 ± 5.20	7.95 ± 4.88	<0.001*	9.55 ± 5.32	8.13 ± 4.66	0.014*
Sudomotor dysfunction	74.7%	100%	0.201	71.8%	80.6%	0.025*	71.8%	84.3%	0.016*

Notes: “*” of P is less than 0.05. Data are mean ± SD or %.

Abbreviations: ABI, ankle brachial index; TBI, toe brachial index; TcPO2, transcutaneous oxygen tension; Slop4, the slope of the chromatic aberration curve in the first 4 minutes.

Table 4 Different Lower Limb Ischemia Indicators on Risk of Sudomotor Dysfunction

	Variable	Odds Ratio (95% CI)	P-value
Model crude	Lower limb arterial ischemia	1.836(1.214–2.776)	0.004*
	Low TBI	1.636(1.069–2.524)	0.026*
	Low TcPO2	2.105(1.142–3.880)	0.017*
Model 1	Lower limb arterial ischemia	1.773(1.094–2.871)	0.020*
	Low TBI	1.408(0.846–2.345)	0.188
	Low TcPO2	2.253(1.116–4.548)	0.023*
Model 2	Lower limb arterial ischemia	1.754(1.076–2.560)	0.024*
	Low TBI	1.395(0.831–2.342)	0.208
	Low TcPO2	2.231(1.100–4.524)	0.026*

Notes: “*” of P is less than 0.05. Model crude: unadjusted. Mode1 1: adjusted for gender, age, BMI, duration of diabetes, diastolic pressure, HbA1c, eGFR, TG, ACR. Mode1 2: adjusted for gender, age, BMI, duration of diabetes, diastolic pressure, HbA1c, eGFR, TG, ACR, hypertension, alcohol consumption, smoking.

Abbreviations: TBI, toe brachial index; TcPO2, transcutaneous oxygen tension; CI, confidence intervals.

Table 5 Association of Different Types of Arterial Ischemia with Slop4 by Multivariate Linear Regression

Clinical Factors	β	p
ABI	0.059	0.200
TBI	0.091	0.047*
TcPO2	0.107	0.022*

Notes: “*” of P is less than 0.05. The three indicators separately adjusted gender, age, BMI, duration of diabetes, diastolic pressure, HbA1c, eGFR and TG.

Abbreviations: ABI, ankle brachial index; TBI, toe brachial index; TcPO2, transcutaneous oxygen tension.

Figure 1 Sudomotor function by the tertile of the ABI, TBI, and TcPO2. (A) Slop4 was not decreased in subjects in the lower ABI tertiles. (B) Slop4 was decreased in subjects in the lower TBI tertile. (C) Slop4 was decreased in subjects in the lower TcPO2 tertile.

Data Sharing Statement

The datasets used and/or analysed during the current study are available from the corresponding author on reasonable request.