Traumatic brain injury among young offenders in France based on the results of the Fleury TBI study

Figures & data

Table 1. Characteristics* of the study population according to gender (N = 332)

Characteristics	Age < 22 years
	Females (n = 30)	Males (n = 302)
Age, mean (SD), yrs	17.8 (2.30)	18.9 (1.69)
>10 yrs education, n (%)	5 (16.7)	135 (44.7)
Occupation^1, n (%)	0	64 (21.2)
Worker	0	21 (7.0)
Employee	0	0
Executive	4 (13.3)	23 (7.6)
Unknown	6 (20.0)	103 (34.1)
Unemployment
Convict status^2, n (%)	14 (46.7)	128 (42.4)
Age at 1st imprisonment^3	17.4 (2.27)	18.2 (1.83)
Mean (SD), yrs
Number of previous imprisonments^4	1.2 (.42)	1.6 (1.25)
Mean (SD)
Total time in jail during the past 5 yrs^5	6.1 (7.38)	7.0 (4.60)
Mean (SD), months

* Descriptive statistics were computed considering missing values. A note indicates when >15% of the data in a group were missing values.

¹ >66% of missing data for females and >30% for males.

² >30% of missing data for females and >18% for males

³ >16% of missing data for females.

⁴ >36% of missing data for females.

⁵ >76% of missing data for females and >18% for males.

Yrs: years.

Table 2. Medical history, drug and alcohol consumptions* of the study population according to gender (N = 332)

	Age < 22 years
	Females (n = 30)	Males (n = 302)
	n (%)	n (%)
History of TBI^1	2 (6.7)	78 (25.8)
Epilepsy	0	12 (4.0)
Psychiatric care	1 (3.3)	24 (8.0)
Anxiolytic treatment	2 (6.7)	11 (3.6)
Antidepressant treatment^2	1 (3.3)	8 (2.7)
Alcohol use	1 (3.3)	99 (32.8)
Regular alcohol use	–	28 (9.3)
Cannabis use^3	3 (10.0)	109 (36.1)
Regular cannabis use^3	1 (3.3)	62 (20.5)

* Descriptive statistics were computed considering missing values. A note indicates when >15% of the data in a group were missing values.

¹ Traumatic Brain Injury.

² >16% of missing data for females.

³ 30% of missing data for females.

Table 3. Description* of reported traumatic brain injury in the study population according to gender (N = 80)

	Age < 22 years
	Female (n = 2)	Male (n = 78)
	n	n (%)
Causes
Road traffic accident	1	17 (21.8)
Sport accident	–	6 (7.7)
Fall	–	8 (10.3)
Violence related	1	19 (24.4)
Combination of causes	–	6 (7.7)
Other	–	12 (15.4)
Follow-up after TBI^1	1	13 (16.7)
LOC^2	2	37 (47.4)
Coma	0	9 (11.5)
Hospitalization for TBI^1	1	22 (28.2)
More than one TBI^1	1	27 (34.6)

* Due to small samples percentages were not computed for females, for males, they were computed considering missing values. A note indicates when >15% of the data in a group were missing values.

¹ Traumatic Brain Injury.

² Loss of consciousness excluding coma.

Table 4. Demographic and penitentiary characteristics according to traumatic brain injury—N = 326

	Presence of TBI^1	Absence of TBI^1	P^2
	(n = 80)	(n = 246)
Age, mean (SD), yrs	19.0 (1.74)	18.7 (1.79)	.19
>10 yrs education, n (%)	37 (46.3)	102 (41.5)	.42
Occupation^3, n (%)			.78
Worker	20 (25.0)	44 (17.9)
Employee	6 (7.5)	14 (5.7)
Executive	–	–
Unknown	6 (7.5)	21 (8.5)
Unemployment	27 (33.8)	78 (31.7)
Age at 1st imprisonment	18.1 (1.92)	18.1 (1.87)	.96
Mean (SD), yrs
Number of previous imprisonments	1.7 (1.51)	1.4 (1.08)	.11
Mean (SD)
Total time in jail during the past 5 yrs^4	7.4 (7.41)	6.6 (7.01)	.16
Mean (SD), months
Convict status^5, n (%)	31 (38.8)	108 (43.9)	.26

¹ Traumatic Brain Injury.

² P were calculated with the t-test or non-parametric Wilcoxon signed-rank test for continuous variables and chi-square test for the others.

³ 34% of missing data.

⁴ when number of additional imprisonments was known, missing data of “Total time in jail during the past 5 yrs” variable have been replaced. Using the 247 known responses, an average total time in jail during the past 5 years was estimated for each number of additional imprisonments. Those averages were used to replace 37 of 79 missing values.

⁵ 19% of missing data.

Yrs: years.

Table 5. Medical history, drug and alcohol consumptions in relation to traumatic brain injury - N = 326.

	Presence of TBI^1	Absence of TBI^1	P^2
	(n = 80)	(n = 246)
	n (%)	n (%)
Perceived health			.0009
Very bad/Bad	7 (8.8)	3 (1.2)
Average	13 (16.3)	28 (11.4)
Good/very good	56 (70.0)	208 (84.6)
Epilepsy	6 (2.4)	6 (7.5)	.08
Psychiatric care	13 (16.3)	12 (4.9)	.002
Anxiolytic treatment	6 (2.4)	6 (7.5)	.08
Antidepressant treatment	2 (.8)	6 (7.5)	.004
Alcohol use	30 (37.5)	69 (28.1)	.14
Regular alcohol use	10 (12.5)	17 (6.9)	.13
Cannabis use	34 (42.5)	77 (31.3)	.12
Regular cannabis use	23 (28.7)	39 (15.9)	.02

¹ Traumatic Brain Injury.

² P were calculated with the χ² test or Fisher’s exact test when necessary.

Figure 1. Prevalence of TBI among studies with more than 100 young prisoners.

Table 6. Common characteristics between TBI populations and prison populations

Population	TBI populations	Prison populations
Age	Young people (incidence peak 15–25)	Young people (Mean age around 30)
Sex-ratio	75% males	95.6% males
Level of education	Low = risk factor to sustain a TBI	Low
Socio-economic status	Low = risk factor to sustain a TBI	Low
Use of alcohol and drugs	Alcohol and drugs = risk factor Alcohol after TBI	High prevalences of use of alcohol, tobacco and cannabis
Psychiatric and psychological disorders	More frequent before and after a TBI than in the population as a whole	More frequent than in the population as a whole
Cognitive disorders	Possible sequelea	Possible cognitive disorders