Characteristics of Traumatic Brain Injury Patients in Korean Military Hospitals During Non-War Years

Article information

J Neurointensive Care. 2021;4(1):6-12
Publication date (electronic) : 2021 April 30
doi : https://doi.org/10.32587/jnic.2020.00325
1Department of Neurosurgery, Armed Forces Capital Hospital, Seongnam, Korea
2Trauma Center, Armed Forces Capital Hospital, Seongnam, Korea
Corresponding Author: Jang Hun Kim, M.D. Department of neurosurgery & Trauma center, Armed Forces Capital Hospital, 81, Saemaeul-ro 177beon-gil, Bundang-gu, Seongnam 13574, Korea Tel: +82-31-787-8490 Fax: +82-31-706-0987 E-mail: jhkimns@naver.com
Received 2020 November 29; Accepted 2021 January 26.

Abstract

Objective

Because of the specialty of the military medical system, there might be different characteristics of patients with traumatic brain injury (TBI) comparing to the patients in university hospitals. However, the characteristics of the soldiers’ TBI has never been reported. Therefore, we tried to identify the different characteristics of TBI patients in military hospitals by comparing them of other hospitals.

Methods

We extracted the data of TBI patients from the databank of the Korean Multicenter TBI study. Patients, who were diagnosed with TBI and admitted to the ten institutions (including two military hospitals) between January 2016 and December 2018, were retrospectively enrolled. They are divided into ‘Military’ and ‘Other’ groups according to the admitted hospitals, and statistical comparisons were conducted on gathered information.

Results

Among 4601 enrolled patients, 133 patients were from two military hospitals and 4468 patients belong to the eight university hospitals. Military patients show significant younger age and male predominance. In general, they have fewer past histories and different trauma mechanisms - more sports-related and lesser traffic accident-related. They usually show higher initial Glasgow coma scale scores and better favorable outcomes - lower incidence of neurologic deterioration in mild TBIs and better modified Rankin Scale scores in moderate to severe TBIs.

Conclusions

Military hospitals usually take care of small numbers of patients who are young males with mild TBIs. Because of the different characteristics of group members and traumatic severity, the patients usually show favorable outcomes. Therefore, the optimized medical system is mandatory.

INTRODUCTION

In 1953, the Armed Forces Medical Command of Republic of Korea (ROK) was established. It provided medical service and welfare for the military service personnel6). Up to date, it offers several military hospitals distributed near corps and is able to handle the situation of potential mass casualties after wartime. Because of the huge gap between the numbers of the patients in wartime and those in non-wartime, military hospitals usually utilize the different medical systems according to the situations3,4,11). During the non-war years (a confrontation with the North), military medical service usually takes care of small numbers of the patients; therefore, a few military hospitals are concentrated and equipped with the medical resources to treat the severe traumatic brain injury (TBI) patients. However, the characteristics of the military personnel’s TBI in ROK during the non-war years has never been reported; and the majority of the literatures on military TBI are limited to the wartime situation such as combat injuries1,7,9).

By the merest chance, two military hospitals (AFCH, Armed Forces Capital Hospital; and AFYH, Armed Forces Yangju Hospital) participated in the Korean multi-centered TBI (KMTBI) study for identifying the clinical features and analyzing risk factors for young TBI patients. They constructed a large databank which includes patients diagnosed with TBI for 3 consecutive years (2016~2018) in participants’ hospitals. By using these data, we could identify the different characteristics of the military personnel’s TBI comparing to those of the general populations. It might be helpful to understand the characteristics of military TBIs and to optimize the military medical systems in non-wartime situations.

MATERIALS AND METHODS

Patients and data acquisition

The data were extracted from the registered data bank system from the KMTBI study. Ten institutions (eight university hospitals and two military hospitals) are participated in the KMTBI study. The patients, who were admitted to the hospitals and diagnosed with definitive TBI from January 2016 to December 2018, were retrospectively enrolled. Patients, who were aged under 15 or who had poor medical records, were excluded. In this study, the data were registered online and were freely accessible to the research team of the institutions. The extracted data contained age, sex, past medical histories, mechanism of trauma, diagnosis, neurologic status including Glasgow coma scale (GCS) scores, treatment modality, and outcomes. The outcome was measured by the modified Rankin Scale scores on discharging date in mild TBI and at six-month in moderate to severe TBIs. In addition, the neurological deterioration was defined when the GCS score decrement is larger than 2 points. The previous study was approved by the Institutional Review Board of the Human Research Center of each institution. The requirement for obtaining informed consent was omitted because it is a retrospective design.

In the current study, the patients were divided into “Military Hospital” group and “Other Hospital” group according to the institution that the patients are admitted to. In addition, patients were classified as mild (13-15) and moderate/severe TBIs (3-12) according to their GCS scores.

Statistical analysis

Baseline characteristics of military hospital groups were examined. Furthermore, comparison analyses between the groups were conducted by two steps; “mild” and “moderate/severe” TBIs according to the GCS scores. Continuous values were presented as mean and standard deviation, and they were compared by using independent t-test. Discontinuous variable data were presented as numbers and percentages, and they were compared by using Chi-square analysis. Statistical analyses were conducted using a standard software (version 23.0, SPSS, IBM, Chicago, IL, USA), and the significance was considered if p < 0.05.

RESULTS

Table 1 demonstrates the comparison of general demographics between military and other hospital groups. Total 133 patients (107 from AFCH and 26 from AFYH) were identified as the military personnel, and they were young and had male predominance with significances. They have less past medical histories including hypertension, diabetes, cardiologic disease, alcohol abuse, and antiplatelet agent medications. In terms of TBI mechanism, they significantly have more frequent association with sports and less association with traffic accidents. More than a half of the military personnel were transferred from other hospitals (55.3%). Regarding diagnosis, concussion and epidural hematoma were more frequent in military group, whereas acute and chronic subdural hematoma were highly occurred in other hospital groups. In military group, most of the patients had mild TBI (88.0%) with better initial GCS scores (14.40±2.24). Consequently, the outcome of modified Rankin Scale (mRS) was favorable in military group.

Comparison between the enrolled patients of military and other hospitals

Table 2 shows the results of comparison between the groups in ‘mild TBI’. The GCS score is significantly higher in military group. Non-specific symptoms such as headache, dizziness, nausea and vomiting, and loss of consciousness are more frequently occurred in military group, and motor weakness is often observed in other hospital groups. Most of the military patients received conservative treatment without surgical interventions, and the outcome (incidence of neurological deterioration, decrement in GCS score >2) was more favorable. The mRS score is slightly higher in military personnel, and it is not significant.

Comparison between mild TBI patients of military and other hospitals

Table 3 presents the results of comparison between the groups in ‘moderate to severe TBIs’. Initial neurologic status according to the GCS score, mental status, symptoms, and signs have no significant differences between the groups. However, the military personnel significantly show favorable outcomes in 3 or 6-months mRS scores.

Comparison between moderate to severe TBI patients of military and other hospitals

The TBI mechanism (A), initial diagnosis (B), initial GCS score and 6-month mRS score (C) are illustrated in Fig. 1.

Fig. 1.

Graphical plots of the trauma mechanisms (A), final diagnosis (B), and the initial GCS scores and final mRS outcomes (C).

DISCUSSION

Herein, we tried to figure out the different clinical features of military personnel’s TBI comparing to the general populations. In general, the military personnel are significantly young and healthy (lower rate of having past medical histories) and show high male predominance. They showed better prognosis including lesser neurologic deterioration in mild TBIs (p=0.004) and lower mRS scores at 3 or 6 months in moderate to severe TBIs (p=0.001). From military medical perspective, military personnel’s TBI should be optimized because of their lesser TBI events and better prognosis.

The TBI patients from military hospitals have never been reported due to the following reasons. First, the incidence of head trauma in the military corps is relatively low due to the limited social activities of the military personnel and their efforts for reducing a non-combat injury. Second, majority of military hospitals’ members is consisted of short-term working military officers (3 to 5 years), and they rarely investigate or report the literatures. Third, due to the situation of prolonged confrontation against the North, the military remains tense and is separated from the society in terms of location as well as a scholastic exchange. Also, the process of the military medical investigation is quite complicated.

Characteristics of military TBIs during the non-war years

The result of the current study would be a good reference for the military doctors working in the military hospitals. In order to identify the clinical characteristics of the military TBI patients, the optimized military medical system can be equipped during this non-war years in ROK. They can place the medical resources in the right place with the most efficient ways. Specifically, the most of the patients in military group are young male soldiers, and they show the clinical differences: lesser past medical diseases, higher incidence of sports-related trauma, lower incidence of traffic accidents, and lesser frequent diagnosis of chronic subdural hematoma12,13). We conclude that the military hospital usually cares mild TBI patients, that the most of them is young male soldiers. Only 10% of the military patients had severe TBI, and others had favorable outcomes which means non-severe TBI (Table 1).

From the ‘mild TBI’ comparison (Table 2), we can draw a conclusion that the clinical manifestation, clinical courses, and outcomes of military mild TBI patients are related to ‘young male’ patients. The patients significantly complain bitterly of non-specific symptoms: headache, dizziness, nausea and vomiting, and loss of consciousness. A larger number of young patients might be related to the sensitive detection of increased intracranial pressure, and the symptoms can be frequently observed among the young age group. On contrary, ‘motor weakness’ is significantly highly observed among other hospital groups: it might be related to the chronic subdural hemorrhage which frequently occurred in elderly patients10). Therefore, the treatment such as burr-hole trephination is more frequently conducted in other hospital groups. In terms of outcome, we can find that no military patients were deteriorated, which means that the military personnel in mild TBI have rarely been worsened to moderate or severe TBIs.

In moderate to severe TBIs (Table 3), the favorable clinical courses and outcome in military personnel are identified. The initial neurologic status, including GCS scores, level of consciousness, and neurological symptom and signs, have no differences between the groups. Treatment modality does not vary among the groups, neither. However, the mRS score in military group is approximately 1 point higher than that in other hospital groups. Because more than a half of the military patients who had no symptoms or had mild symptoms (mRS 0 to 1) were treated, physicians should actively treat the patients.

Clinical implication of the study

We identify the low incidence of TBI in military personnel and small numbers of ‘severe’ patients which requires the human as well as medical resources for treating. In non-wartime years, the military hospitals in ROK divided their works and specialties for better efficacy. If we have TBI patients (especially, severe), they initially visit the nearest military hospital and are transferred to the superior hospitals. Consequently, AFCH carries on providing the medical service as the supremacy hospital. In addition, AFYH is located on front lines and usually prepare for the potential combat injuries. Maybe this systematic difference leads to the higher transfer rates of military hospitals (55.3%). Instead, the medical command operates an all-time helicopter emergency transporting systems in order to assess and manage the patients better2). The fastest transporting system may enable the better clinical outcomes. According to our results, two hospitals greatly manage the military TBI patients, and the outcomes are favorable.

Limitations

The present study has several limitations. First, the data were extracted from the databank system of KMTBI, and they did not include radiological images. Therefore, known prognostic factors observed in brain computed tomography (CT), such as poor Marshall or Rotterdam CT scores, were omitted5,8). Second, the data were registered from each different hospital’s reviewers, and there might be an inter-observer bias.

CONCLUSIONS

Military hospitals usually take care of young male soldiers with mild TBIs. Because of the different characteristics of group members and traumatic severity, the patients usually survive and show favorable outcomes. Therefore, the optimized treatment should be mandatory.

Notes

Conflict of interest

No potential conflict of interest relevant to this article was reported.

Acknowledgements

The clinical data was obtained from the database of Korean Multi-centered Traumatic Brain Injury 2019 study (KMTBI-2019).

The authors appreciate to the 10 principal investigators of each institution: Seong-Jong Lee, Sang Hoon Yoon, Ki Seong Eom, Kyung-Jae Park, Sung-Kon Ha, Jin-gyu Choi, Kwang Wook Jo, Suk Hyung Kang, Jongyeon Kim, and Jong Hyun Kim.

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Article information Continued

Fig. 1.

Graphical plots of the trauma mechanisms (A), final diagnosis (B), and the initial GCS scores and final mRS outcomes (C).

Table 1.

Comparison between the enrolled patients of military and other hospitals

Parameters Military Hospitals (n=133) Other hospitals (n=4468) OR or MD 95% CI p-value
Age 23.2 ±7.688 61.11 ±17.443 -37.905 -40.879 -34.931 0.000
Sex (male) 131 0.985 3075 0.688 29.672 7.333 120.071 0.000
Hypertension 5 0.038 1780 0.398 16.952 6.924 41.508 0.000
Diabetes 1 .8% 889 0.199 32.788 4.578 234.817 0.000
Cardiologic disease 3 0.023 399 0.089 4.249 1.347 13.409 0.002
Hepatic disease 1 .8% 108 0.024 3.270 0.453 23.602 0.149
Alcohol abuse 0 0 199 0.045 0.001
Smoking 49 0.368 695 0.156 0.316 0.220 0.453 0.000
Antiplatelet medication 1 .8% 438 0.098 14.346 2.001 102.857 0.000
Mechanism 0.000
 Traffic accident 20 0.15 1280 0.286
 Sports-related 20 0.15 33 0.007
 Fall down 65 0.489 2145 0.48
 Assault 20 0.15 276 0.062
 Unknown 8 0.06 734 0.164
Transfer 73 0.553 1436 0.326 0.391 0.276 0.554 0.000
Diagnosis 0.000
 Concussion, Skull fx. 45 0.338 636 0.142
 EDH 19 0.143 374 0.084
 Acute SDH 27 0.203 1648 0.369
 Chronic SDH 6 0.045 603 0.135
 Contusion, ICH 14 0.105 622 0.139
 Traumatic SAH, IVH 20 0.15 526 0.118
 Others 2 0.016 59 0.013
GCS score 14.4 ±2.243 13.11 ±3.389 1.293 0.694 1.891 0.000
 Mild 117 0.88 3465 0.776 0.015
 Moderate 5 0.038 394 0.088
 Severe 11 0.083 609 0.136
mRS (3 or 6 months) 0.58 ±1.298 1.26 ±1.953 -0.680 -1.014 -0.345 0.000
 0 or 1 126 0.947 3550 0.795 0.000
 2 or more 7 0.053 918 0.205

OR: Odds ratio, MD: Mean difference, CI: Confidential index, fx.: fracture, EDH: Epidural hematoma, SDH: Subdural hematoma, ICH: Intracerebral hemorrhage, SAH: Subarachnoid hemorrhage, IVH: Intraventricular hemorrhage, GCS: Glasgow coma scale, mRS: modified Rankin Scale.

Table 2.

Comparison between mild TBI patients of military and other hospitals

Parameters Military Hospitals (n=117) Other hospitals (n=3465) OR or MD 95% CI p-value
GCS score 0.001
13 0 0 341 0.113
14 8 0.068 319 0.106
15 109 0.932 2354 0.781
Symptom
 Headache 97 0.829 2244 0.648 0.379 0.233 0.616 0.000
 Dizziness 56 0.479 563 0.162 0.211 0.145 0.307 0.000
 Nausea, vomiting 42 0.359 315 0.091 0.179 0.120 0.265 0.000
 LOC 59 0.504 728 0.21 0.261 0.180 0.379 0.000
 Aphasia, dysarthria 3 0.026 218 0.063 2.551 0.804 8.094 0.099
 Motor weakness 2 0.017 511 0.147 9.947 2.450 40.378 0.000
 Altered mentality 3 0.026 161 0.046 1.852 0.582 5.891 0.250
 Amnesia 6 0.051 117 0.034 0.647 0.279 1.5 0.306
Treatment 0.003
 Conservative 106 0.906 2621 0.756
 Burr-hole 6 0.051 560 0.162
 Open craniotomy 5 0.043 183 0.053
 Decompressive craniectomy 0 0 80 0.023
 Others 0 0 21 0.006
Deterioration 0 0 121 0.035 0.004
3-month OPD f/up 61 0.521 1978 0.571 1.221 .844 1.766 0.288
  Symptomatic 28 0.459 1093 0.544 1.405 .843 2.342 0.191
  Asymptomatic 33 0.541 917 0.456
mRS 1.478 .961 2.274 0.073
 0 89 0.761 2365 0.683
 1 or more 28 0.239 1100 0.317

OR: Odds ratio, MD: Mean difference, CI: Confidential index, GCS: Glasgow coma scale, LOC: Loss of consciousness, OPD: Out-patient department, mRS: modified Rankin Scale.

Table 3.

Comparison between moderate to severe TBI patients of military and other hospitals

Parameters Military Hospitals (n=16) Other hospitals (n=1124) OR or MD 95% CI p-value
GCS score 6.63 ±3.777 8.15 ±3.732 -1.520 -4.121 1.080 0.252
 Mild 0 0 121 0.108 0.132
 Moderate 5 0.313 394 0.351
 Severe 11 0.688 609 0.542
Level of consciousness
 Alert 0 0 79 0.07 0.133
 Drowsy 2 0.125 335 0.298
 Stupor 8 0.5 416 0.37
 Coma 6 0.375 294 0.262
Symptom & Signs
 Bilateral fixed pupils 6 0.375 207 0.184 0.376 0.135 1.047 0.052
 Unilateral dilated pupil 3 0.188 83 0.074 0.346 0.097 1.237 0.143
 Motor weakness 3 0.188 102 0.091 0.432 0.121 1.543 0.236
 Unresponsiveness 0 0 18 0.016 0.986 0.979 0.993 0.610
Another major organ injury 5 0.313 221 0.197 0.538 0.185 1.566 0.248
Operation 0.522
 Conservative Tx. 6 0.375 502 0.447
 Burr-hole trephination 0 0 90 0.08
 Open craniotomy 4 0.25 150 0.133
 Decompressive craniectomy 6 0.375 382 0.34
Medical treatment 0.066
 Conservative Tx. 14 0.875 888 0.79
 ICP monitoring 2 0.125 29 0.026
 Hypertonic saline 0 0 57 0.051
 Coma therapy 0 0 51 0.045
 Hypothermia 0 0 99 0.088
Complication
  Medical 6 0.375 392 0.362 0.947 0.342 2.625 0.916
 Surgical 3 0.188 90 0.08 0.381 0.097 1.501 0.152
mRS (3 or 6 months) 3.06 ±2.435 4.06 ±2.009 -0.997 -1.993 -0.002 0.049
 0 or 1 9 0.563 206 0.183 0.001
 2 or 3 0 0 205 0.182
 4 or 5 2 0.125 305 0.271
 6 5 0.313 408 0.363

OR: Odds ratio, MD: Mean difference, CI: Confidential index, GCS: Glasgow coma scale, ICP: Intracranial pressure, mRS: modified Rankin Scale.