Risk factors and predictive models for sequelae of heat stroke primarily involving cerebellar dysfunction

Figures & data

Figure 1. The flow chart of all excluded and included patients with heatstroke.

Figure 2. Prognosis and balance function assessments of patients with different sequelae after heatstroke.

Prognosis and balance function assessments of the patients 6 months after heatstroke. Data are shown as mean ± SEM, *p < 0.05, **p < 0.01 vs the cerebellar injury group. MBI: the Modified Barthel Index; ICARS: International Cooperative Ataxia Rating Scale; BBS: Berg Balance Scale.

Table 1. Univariate analysis of the risk factors for the sequelae in heatstroke patients.

	sequelae (n = 29)	non-sequelae (n = 93)	t/Z/χ^2	P1	cerebellar sequelae (n = 15)	other sequelae (n = 14)	t/Z/χ^2	P2
Age (year)	31(21.3 ~ 45.5)**	22 ± 0.5	−2.3	0.02	22(18 ~ 41)	34 ± 4	−1.34	0.18
Duration of DOC (day)	7.5(4 ~ 26.8)**	0(0 ~ 4)	−8.15	<0.001	5(3.8 ~ 15.5)	15 ± 4.9	−0.31	0.76
Duration of hyperthermia (h)	6.5(4.3 ~ 8)*	2.6 ± 0.29	−4.68	<0.001	6(4 ~ 8.8)^†	5.5 ± 0.89	−0.53	0.6
GSC scales	7.21 ± 0.86**	14.5 ± 0.2	−12.26	<0.001	5.9 ± 0.91^††	8.6 ± 1.4	−1.67	0.002
Tc (℃)	41.6(39.9 ~ 42)**	38.9 ± 0.29	−5.41	0.001	40.8 ± 0.43	40.8 ± 0.38	−0.04	0.284
Systolic pressure(mmHg)	80(71.3 ~ 85)	116 ± 1.5	−5.8	<0.001	86.5 ± 3.4^†	90.7 ± 5.9	−0.63	0.04
Diastolic pressure(mmHg)	44.5(40.5 ~ 53)*	67.2 ± 1.2	−4.16	<0.001	45(42.3 ~ 51)	56.1 ± 4.5	−0.66	0.51
CK (U/L)	1338(897 ~ 2040.5)**	1392 ± 361.5	−3.27	0.001	1364(1097.3 ~ 5841.2)*	1363(1275 ~ 3189)	−1.5	0.13
Myohemoglobin (μg/L)	688(131 ~ 2128)**	656.3 ± 88.2	−1.34	0.17	1363 ± 277.8 *	280(97.7 ~ 2898)	−1.75	0.08
hs-cTnT (pg/mL)	233(89.7 ~ 682.2)**	107 ± 19.75	−3.43	0.001	655.3 ± 155.8 *	120(52.3 ~ 900)	−1.93	0.053
ALT (U/L)	503.2 ± 195.1**	231.6 ± 44.9	2.01	0.01	782.9 ± 363.4 **^†	201.1 ± 64	1.52	0.048
AST (U/L)	668.4 ± 267.4**^†	158.1 ± 26.1	3.77	<0.001	1079 ± 497.9 **	225 ± 66.6 *	0.39	0.91
Bilirubin (μmol/L)	46.3 ± 7.1 **^††	22.4 ± 1.5	5.0	<0.001	53 ± 11.2 **	39.2 ± 8.6 *	0.97	0.25
LDH (U/L)	1169 ± 225 **^††	351 ± 31.5	5.81	<0.001	1166 ± 296 **	1173 ± 365 **	−0.01	0.34
PT (sec)	22.1 ± 1.6 **^†	15.4 ± 0.2	6.91	<0.001	25.9 ± 2.3 **	18.4 ± 1.6	1.79	0.1
APTT (sec)	59.5 ± 7 **^†	41.1 ± 1.6	3.37	<0.001	56.7 ± 9.4 **	62.3 ± 10.6 *	0.58	0.23
Lymphocyte count (10^9/L)	0.94 ± 0.15	1.69 ± 0.07	−4.78	0.7	0.61 ± 0.13 **^††	1.3 ± 0.3	−2.49	0.01
PLT count (10^9/L)	63.5(30.8 ~ 108) **	181 ± 6	−4.17	<0.001	75.5 ± 15.2 **^††	69.5(45 ~ 111.3)	−2.18	0.003
HCT	0.38 ± 0.01**	0.41 ± 0.01	−3.7	0.002	0.37 ± 0.02 **	0.38 ± 0.02 *	−0.22	0.61
HLA-DR/CD14	76.6(56 ~ 84.5)*	85.3 ± 1.1	−2.9	0.004	63 ± 6.5 **	76.6(14.1 ~ 83.8)	−0.35	0.73
CD14+	28.6 ± 3.9 *^†	12.9 ± 1.2	3.09	0.015	35.6 ± 6.6 **^††	20.2 ± 2.9	1.77	0.008
D-dimer (μg/mL)	15.6(2.8 ~ 20)	7.3 ± 3.3	−3.69	<0.001	19.9(5.67 ~ 20)	11 ± 3.3	−2.14	0.032
Creatinine (μmol/L)	141.2 ± 14.7	107.8 ± 8	2.03	0.12	149.4 ± 17.7	132.5 ± 24.2	0.57	0.22
PH	7.4 ± 0.01^††	7.38 ± 0.01^††	1.02	0.83	7.4 ± 0.02^††	7.36 ± 0.01**	1.42	0.007
AB	22.34 ± 0.9^††	21.2 ± 0.19^†	0.84	0.06	20.9 ± 1.2^††	24.7 ± 1.2 *	0.99	0.003
SB	22.49 ± 0.74 *^††	21.7 ± 0.19^††	0.63	0.029	22 ± 0.99^†	23.2 ± 1.2 *	1.09	0.026
K^+ (mmol/L)	3.7 ± 0.1	3.9 ± 0.1	−0.55	0.81	3.5 ± 0.2	3.9 ± 0.1	−1.8	0.79
Na^+ (mmol/L)	141 ± 0.7	141 ± 0.3	0.68	0.34	142 ± 0.8	140 ± 1.2	1.45	0.08
WBC (10^9/L)	9.94 ± 0.8	9.19 ± 0.4	0.88	0.47	9.1 ± 0.8	10.8 ± 1.5	−1.0	0.15
Neutrophil count (10^9/L)	8.23 ± 0.78	6.8 ± 0.39	1.74	0.71	7.9 ± 0.7	8.57 ± 1.5	−0.42	0.09
NSE (μg/L)	16 ± 1^††	12 ± 0.4^††	1.63	0.22	17 ± 1.5^††	13 ± 0**	2.56	0.001
SOFA	6.9 ± 0.75 **	1(0 ~ 2)	−6.1	<0.001	7.9 ± 0.7 **^††	5.6 ± 1.3 **	1.36	0.006
APACHE II	14.5 ± 1.4 **	2(0 ~ 4)^††	−6.6	<0.001	16.3 ± 1.5 **	12.6 ± 2.3 **	1.3	0.096
Hypotension (n)	18 **	4	43.27	<0.001	8	10	1.01	0.27
Gastrointestinal bleeding (n)	17 **	8	33.95	<0.001	10	7	0.83	0.297
MODS (n)	26 **	56	8.69	0.003	15	11	3.59	0.1
Cardiac damage (n)	26 **	30	25.99	<0.001	15^†	11	4.97	0.42
Coagulation disorder (n)	24 **	29	22.1	<0.001	15	9	2.44	0.14
Metabolic acidosis (n)	10 **	8	6.98	0.01	5	5	1.83	0.17
Rhabdomyolysis (n)	24 *	53	5.2	0.017	15	9	2.43	0.14
Convulsion (n)	13	35	0.48	0.315	8	5	2.89	0.09

Data are shown as mean ± SEM or median (Q1~Q3), *p < 0.05, **p < 0.01 vs the none-sequelae group. ^†p < 0.05, ^††p < 0.01 vs the other sequelae group. P1 value and t/Z/χ² in front of it indicated the differences between groups of sequelae and none-sequelae. P2 value and t/Z/χ² in front of it indicated the differences between groups of cerebellar sequelae and other sequelae.

GCS: Glasgow coma scale; h: hour; MODS: multiple organ dysfunction syndrome. WBC: white blood count; PLT: blood platelet; HCT: red blood cell specific volume; PT: prothrombin time; APTT: activated partial thromboplastin time; ALT: alanine transaminase; AST: aspartate aminotransferase; CK: creatine kinase; LDH: lactate dehydrogenase; hs-cTnT: high-sensitivity cardiac troponin T; PH: power of hydrogen; AB: actual bicarbonate; SB: standard bicarbonate; HLA: human leukocyte antigen; K⁺: potassium concentration, Na⁺: sodium concentration. SOFA: sequential organ failure assessment; APACHE-II: Acute Physiology and Chronic Health Evaluation-II.

Figure 3. ROC curve of risk factors to sequelae and cerebellar dysfunction of heatstroke patients and internal/external validation of the risk prediction score system.

(a) Receiver Operating Characteristic Curve (ROC curve) of coma, age, and APACHE-II score and the risk prediction score system; (b) ROC curve of risk prediction score system in modeling cohort; (c) ROC curve of SOFA score for cerebellar dysfunction; (d) The probabilities of sequelae correspond to different risk scores; (e) C-index of internal validation of bootstrapping sampling; (f) The ROC of coma, age, and APACHE-II score for predicting sequelae of heatstroke on external verification.

Table 2. Multivariate analysis of relevant factors of the sequelae in patients with heatstroke.

relevant factors	B	SE	Wald	P	Exp (B)	OR (95%CI)
Coma	3.011	0.816	13.613	0.000	20.308	4.102–100.533
APACHE II score > 10	2.998	0.999	9.005	0.003	20.05	2.829–142.101
Age ≤30			7.582	0.023
31<age ≤45	1.623	0.949	2.926	0.087	5.067	0.789–32.528
Age ≥46	3.787	1.547	5.995	0.014	44.137	2.129–915.011
Constant	−3.763	0.679	30.681	0.000	0.023

Table 3. The prediction scale of risk factors for sequelae of heat stroke.

Risk Factor	Score
Age
≤30	0
31 ~ 45	1
≥46	2
Coma
NO	0
YES	2
APACHE II scale
≤10	0
＞10	2
Total	0 ~ 6

Table 4. Incidence of the sequelae after heatstroke corresponding to different risk grades.

Score classification	Total score	Incidence (%)	Risk classification
I	0–1	4.6	Low
II	2–3	40.0	Moderate
III	4–6	95.0	High

Data availability statement

Data available on request from authors.