Prospective observational cohort study on epidemiology, treatment and outcome of patients with traumatic brain injury (TBI) in German BG hospitals

Abstract

Objectives: Since 2000/2001, no large-scale prospective studies addressing traumatic brain injury (TBI) epidemiology in Germany have been published. Our aim was to look for a possible shift in TBI epidemiology described in other European countries, to look for possible changes in TBI management and to identify predictors of 1-year outcome especially in patients with mild TBI.

Design: Observational cohort study.

Setting: All patients suffering from a TBI of any degree between 1 October 2014 and 30 September 2015, and who arrived in one of the seven participating BG hospitals within 24 hours after trauma, were included.

Participants: In total, 3514 patients were included.

Outcome measures: Initial care, acute hospital care and rehabilitation were documented using standardised documentation forms. A standardised telephone interview was conducted 3 and 12 months after TBI in order to obtain information on outcome.

Results: Peaks were identified in males in the early 20s and mid-50s, and in both sexes in the late 70s, with 25% of all patients aged 75 or older. A fall was the most frequent cause of TBI, followed by traffic accidents (especially bicyclists). The number of head CT scans increased, and the number of conventional X-rays of the skull decreased compared with 2000/2001. Besides, more patients were offered rehabilitation than before. Though most TBI were classified as mild, one-third of the patients participating in the telephone interview after 12 months still reported troubles attributed to TBI. Negative predictors in mild TBI were female gender, intracranial bleeding and Glasgow Coma Scale (GCS) 13/14.

Conclusion: The observed epidemiologic shift in TBI (ie, elderly patients, more falls, more bicyclists) calls for targeted preventive measures. The heterogeneity behind the diagnosis 'mild TBI' emphasises the need for defining subgroups not only based on GCS.

Keywords: accident & emergency medicine; epidemiology; neurological injury; neurosurgery.

Figure 1

Patient flow in the study. n.s., not specified; SR, self-rating; FR, foreign-rating.

Figure 2

Age and gender distribution (n=3514).

Figure 3

(A) Distribution of causes for traumatic brain injury (n=3514). (B) Distribution of causes for traffic accidents (n=757). Numbers indicate %.

Figure 4

Association between patients’ age, gender and cause of traumatic brain injury (TBI) with TBI severity. TBI severity was classified by Glasgow Coma Scale (GCS) at the emergency room or, if then sedated, at the accident site before sedation. Shown are absolute numbers. Patients with missing values were excluded. The first row shows male patients, the second row female patients. The first column shows young (≤30 years), the second column middle-aged (31–65 years) and the third column elderly (>65 years) patients. Note that moderate-to-severe TBI were more frequent in elderly patients with falls (male and female), and in middle-aged male with falls or traffic accidents (n=3032).

Figure 5

(A) Duration of intensive care unit (ICU) treatment (n=842). (B) Duration of acute hospital care (n=2375).

Figure 6

Medical complications during acute hospital care. Multiple nominations were permitted (n=2375).

Figure 7

Telephone interview: Answer on the question ‘Do you still have troubles that result from traumatic brain injury?’ after 3 (A) and 12 months (B). Answer on the question ‘Did your occupation change due to traumatic brain injury?’ after 3 (C) and 12 months (D). n.s., not specified (n=450).

Figure 8

Predictors of persisting TBI-related health complaints in patients with mild TBI after 12 months. Included in this analysis were all patients with GCS 13–15 when arriving at the emergency room or, if then sedated, with GCS 13–15 at the accident site before sedation. Results of self-rating interviews and foreign rating interviews (answers provided by primary caregiver) were pooled. Shown are the ORs including the 95% CI based on a logistic regression model. n.s., not specified; vs, versus (n=390).