Differences in serum IL-6 response after 1 °C rise in core body temperature in individuals with spinal cord injury and cervical spinal cord injury during local heat stress

Figures & data

Table 1. Characteristics of participating subjects.

	AB Subjects	TLSCI subjects	CSCI Subjects
n	8	10	9
Age (years)	39.3 ± 1.0	40.4 ± 2.6	36.6 ± 2.8
Height (cm)	174.5 ± 2.6	172.8 ± 1.9	173.1 ± 2.8
Weight (kg)	70.0 ± 2.9	66.6 ± 4.0	57.4 ± 3.0^†
BMI(kg/m^2)	23.1 ± 0.8	22.2 ± 1.0	18.8 ± 1.1^†
Spinal cord injury		Th4-L1 (TSCI =9, LSCI =1) ASIA A (n = 10)	C5-7, ASIA A (n = 8) and B (n = 1)
Duration of LBH (min)	62.8 ± 4.4	65.0 ± 5.4	41.3 ± 3.8^†^¶
Time since injury (years)		16.1 ± 3.4	16.4 ± 4.1

Data are mean ± SEM.

† p < .05, relative to AB,.

¶ p < .05, relative to TLSCI.

AB: able-bodied; TLSCI: spinal cord injury; CSCI: cervical spinal cord injury; LBH: lower body heat stress.

Table 2. Thermal responses and hemodynamic variables during normothermia and LBH.

	AB Subjects	TLSCI Subjects	CSCI subjects
Core temperature (°C )
Normothermia	36.8 ± 0.1	36.6 ± 0.1	36.5 ± 0.2
LBH	37.8 ± 0.1**	37.6 ± 0.1**	37.6 ± 0.2**
Mean skin temperature (°C )
Normothermia	35.3 ± 0.1	35.1 ± 0.2	34.7 ± 0.3
LBH	38.2 ± 0.1**	37.9 ± 0.2**	37.1 ± 0.2**†
Mean upper body skin temperature (°C )
Normothermia	34.7 ± 0.2	34.5 ± 0.3	34.2 ± 0.4
LBH	36.8 ± 0.4**	36.4 ± 0.4**	35.8 ± 0.4**†
Mean lower body skin temperature (°C )
Normothermia	34.4 ± 0.2	33.8 ± 0.4	33.1 ± 0.6†
LBH	40.0 ± 0.5**	39.9 ± 0.5**	39.3 ± 0.5**
Cardiac output (l/min)
Normothermia	5.8 ± 0.2	5.3 ± 0.2	4.7 ± 0.1†
LBH	8.1 ± 0.5**	6.9 ± 0.3**	6.0 ± 0.2**†
Stroke volume (ml)
Normothermia	85.0 ± 2.5	88.9 ± 5.3	78.3 ± 4.8
LBH	83.0 ± 5.6	90.4 ± 5.3	84.1 ± 3.8
Heart rate (beats/min)
Normothermia	67.5 ± 0.8	61.9 ± 3.0	59.0 ± 2.4†
LBH	98.7 ± 2.2**	83.8 ± 4.2**	69.3 ± 3.3**†
Mean blood pressure (mmHg)
Normothermia	83.2 ± 3.8	91.7 ± 3.7	78.5 ± 5.1
LBH	84.0 ± 3.0	86.7 ± 4.5	83.1 ± 4.6

Data are mean ± SEM.

† p < .05, compared with AB.

‡ p < .05, compared with TLSCI.

* p < .05, compared with normothermia.

** p < .01, compared with normothermia.

AB: able-bodied; TLSCI: spinal cord injury; CSCI: cervical spinal cord injury; LBH: lower body heat stress.

Figure 1. Serum IL-6 level during LBH in AB TLSCI and CSCI. Data are mean ± SEM. *p < .05, **p < .01, relative to normothermia. AB: able-bodied; TLSCI: thoracic and lumbar spinal cord injury; CSCI: cervical spinal cord injury; NT: normothermia; LBH: lower body heat stress.

Figure 2. ΔIL-6 in AB TLSCI and CSCI. Data are mean ± SEM. †p < .05, compared with AB; by the post hoc test. AB: able-bodied; TLSCI: thoracic and lumbar spinal cord injury; CSCI: cervical spinal cord injury; NT: normothermia; LBH: lower body heat stress.

Table 3. Changes in blood cell count, haematocrit, CRP and TNF-α during lower body heat stress.

	AB subjects	TLSCI subjects	CSCI Subjects
Hematocrit (%)
Normothermia	43.7 ± 0.8	41.7 ± 0.9	40.4 ± 0.8†
LBH	45.9 ± 0.7**	42.4 ± 0.9†	41.0 ± 0.8†
Leukocyte count (×10^8/l)
Normothermia	65.2 ± 5.6	48.8 ± 4.2	67.2 ± 5.1
LBH	89.6 ± 10.1**	57.9 ± 4.4**†	77.0 ± 5.6**
Monocyte count (×10^8/l)
Normothermia	4.0 ± 0.3	3.3 ± 0.3	3.7 ± 0.3
LBH	4.5 ± 0.3*	3.4 ± 0.2	3.8 ± 0.3
Cortisol (μg/dl)
Normothermia	10.2 ± 0.6	8.2 ± 0.8	10.5 ± 1.7
LBH	13.4 ± 3.1	6.9 ± 0.6	6.2 ± 1.1*
CRP (ng/ml)
Normothermia	390.5 ± 214.9	1629.4 ± 768.4	470.7 ± 103.5
LBH	444.5 ± 249.9*	1653.3 ± 759.8	501.3 ± 103.2
TNF-α (pg/ml)
Normothermia	0.8 ± 0.1	1.1 ± 0.2	1.1 ± 0.2
LBH	0.8 ± 0.1	1.1 ± 0.1	1.0 ± 0.2

Data are mean ± SEM.

† p < .05, compared with AB.

‡ p < .05, compared with TLSCI.

* p < .05, compared with normothermia.

** p < .01, compared with normothermia.

AB: able-bodied; TLSCI: spinal cord injury; CSCI: cervical spinal cord injury; LBH: lower body heat stress.

Figure 3. Plasma adrenaline levels during LBH in AB TLSCI and CSCI. Data are mean ± SEM. †p < 0.05, compared with AB; *p < .05, compared with normothermia; by the post hoc test. AB: able-bodied; TLSCI: thoracic and lumbar spinal cord injury; CSCI: cervical spinal cord injury; NT: normothermia; LBH: lower body heat stress.

Figure 4. Cardiac output during LBH in AB SCI and CSCI. Data are mean ± SEM. †p < .05, compared with AB; **p < .01, compared with normothermia; by the post hoc test. AB: able-bodied; TLSCI: thoracic and lumbar spinal cord injury; CSCI: cervical spinal cord injury; NT: normothermia; LBH: lower body heat stress.