Post-concussion symptoms three months after mild-to-moderate TBI: characteristics of sick-listed patients referred to specialized treatment and consequences of intracranial injury

Figures & data

Table 1. Demographic, preinjury and injury-related characteristics 8–12 weeks post-injury

Variable	n	With intracranial abnormalities n(%)	Normal CT/MRI n(%)	Total sample n(%)
Preinjury factors
Age, mean (SD)	116	45 (9)	42 (9)	42 (9.8)
Sex, female	116	12 (43)	52 (55)	69 (56)
Education, mean (SD)	116	15 (3)	16 (2)	16 (2.5)
Married/Cohabitant	116	20 (74)	50 (57)	77 (58)
Child(ren) in household	116	14 (51)	40 (49)	59 (50)
Self-reported history of
Anxiety	116	2 (6)	4 (4)	6 (4)
Depression	116	4 (14)	12 (14)	17 (14)
Migraine/Headache	116	7 (25)	14 (17)	23 (19)
Previous concussion	115	6 (21)	38 (47)	49 (42)
≥2 previous concussions		0 (0)	16 (19)	18 (15)
Other somatic diseases	116	17 (57)	42 (52)	57 (48)
Injury-related factors
Cause of injury	115
Falls		18 (59)	27 (33)	49 (42)
Traffic accidents		4 (14)	17 (20)	23 (19)
Sports		3 (10)	10 (12)	14 (11)
Violence		2 (6)	4 (4)	6 (4)
Exposure to inanemate objects		0 (0)	21 (25)	23 (19)
CT/MRI findings, traumatic		27 (100)	80 (100)	27 (22)
Injury severity by ACRM criteria	116
Mild		21 (78)	79 (99)	109 (94)
Moderate		6 (21)	1 (1)	7 (5)
Loss of consciousness (LOC)	115
< 30 min		15 (60)	21 (25)	37 (31)
30 min – 24 hours		3 (10)	0 (0)	3 (3)
No LOC		5 (18)	49 (61)	61 (52)
Not registered		3 (10)	10 (12)	14 (11)
Post-traumatic amnesia (PTA)	115
<1 hour		10 (36)	23 (28)	35 (29)
1 hour – 24 hours		10 (36)	6 (7)	16 (13)
25 hours – 7 days		2 (6)	0 (0)	2 (2)
No PTA		5 (18)	39 (48)	51 (43)
Not registered		0 (0)	11 (13)	11 (9)
Injured at workplace	114	3 (10)	11 (13)	16 (13)
Under the influence of alcohol at time of injury	116	8 (29)	9 (10)	17 (14)

Table 2. Results of neuropsychological screening

Neuropsychological tests	Standardized score Mean (SD)	Neuropsychological tests	Standardized score Mean (SD)
Psychomotor speed		Executive functions
TMT^a 1, 2 and 3	11 (3)	TMT^a 4	10 (2)
TMT^a 5	12 (2)	CWIT^2 3 and 4	11 (3)
CWIT^2 1	9 (3)
CWIT^2 2	10 (3)
Coding^3	11 (3)
Attention and concentration		Verbal abilities
Ruff 2 & 7 Total speed^4	58 (11)	Vocabulary^3	10 (2)
Ruff 2 & 7 Total accuracy^4	48 (7)	Similarities^3	12 (3)
Learning and memory		Visuospatial abilities
CVLT-II^5 Total learning	60 (3)	Matrix Reasoning^3	13 (3)
CVLT-II^5 Short delay free recall	56 (9)	Block Design^3	11 (2)
CVLT-II^5 Long delay free recall	56 (9)
Prospective memory		General ability index (GAI)^3	111 (13)
MIST^6 Total PMT	67 (28)

^aTrail Making Test (TMT) from the Delis–Kaplan Executive Function System (D-KEFS), ²Color Word Interference Test, ³Wechler Adult Intelligence Scale 4^th Edition, ⁴The Ruff 2 & 7 Selective Attention Test, ⁵Verbal Learning Test – II, ⁶Memory for Intentions Test – Prospective Memory Test, ^ƗT-test.

Table 3. Multiple linear regression analyses

Variabel	F	p	R^2	Coeff.	Beta	SE	t	P>|t|	95% CI
RPQ^1	(3, 103) = 3.16	0.028	0.08
Radiological Findings (Yes)				−7.42	−0.3	2.56	−2.90	0.005	−12.5, −2.35
Previous mTBI^4 (Yes)				−3.06	−0.14	2.14	−1.43	0.156	−7.29, 1.18
Years of education				−0.15	−0.3	0.45	−0.33	0.742	−1.04, 0.74
PHQ-9^2	(3, 100) = 3.22	0.026	0.08
Radiological Findings (Yes)				−3.41	−0.31	1.11	−3.06	0.003	−5.62, −1.2
Previous mTBI^4 (Yes)				−0.52	−0.06	0.93	−0.56	0.574	−2.37, 1.32
Years of education				−0.08	−0.04	0.2	−0.42	0.673	−0.47, 0.31
PTSS-10^3	(3, 99) = 3.47	0.019	0.1
Radiological Findings (Yes)				−7.18	−0.32	2.32	−3.10	0.003	−11.8, −2.58
Previous mTBI^4 (Yes)				−3.08	−0.16	1.95	−1.58	0.117	−6.95, 0.79
Years of education				−0.41	−0.1	0.41	−1.00	0.321	−1.22, 0.41
Insomnia Severity Index	(3, 95) = 1.74	0.163	0.05
Radiological Findings (Yes)				−3.50	−0.25	1.58	−2.21	0.029	−6.65, −0.36
Previous mTBI^4 (Yes)				−0.1	−0.01	1.33	−0.07	0.942	−2.74. 2.55
Years of education				−0.25	−0.1	0.28	−0.91	0.366	−0.8, 0.3
QOLIBRI^5	(3, 98) = 5.82	0.001	0.15
Radiological Findings (Yes)				16.5	0.32	5.08	3.25	0.002	6.4, 26.54
Previous mTBI^4 (Yes)				−4.81	−0.1	4.16	−1.16	0.251	−13.6, 3.45
Years of education				0.91	−0.1	0.9	−1.02	0.309	−2.69, 0.86
EQ VAS^6	(3, 101) = 1.64	0.18	0.05
Radiological Findings (Yes)				8.27	0.2	4.4	1.86	0.066	−0.5, 17.1
Previous mTBI^4 (Yes)				−1.80	−0.05	3.73	−0.48	0.630	−9.2, 5.6
Years of education				−0.03	−0.004	0.78	−0.04	0.969	−1.6, 1.5

¹Rivermead Post-concussion Questionnaire, ²Patient Health Questionnaire-9, ³Post-traumatic Symptoms Scale, ⁴Mild Traumatic Brain Injury, ⁵Quality of Life after Brain Injury, ⁶EuroQol-5D Visual Analog Scale

Figure 1. Mean scores on RPQ and its subscales from the total sample (green) and with the sample divided into patients without intracranial abnormalities (gray) and with intracranial abnormalities (blue). Stars mark significant differences between patients without and with intracranial abnormalities

Figure 2. Health-Related Quality of Life as measured by QOLIBRI-OS, by patients with and without intracranial abnormalities

Table 4. Neuropsychological screening of patients with and without intracranial abnormalities, standardized scores

Neuropsychological test	p-value	Normal CT/MRI, median (IQR)	With intracranial abnormalities, median (IQR)	U
Psychomotor speed
Trail making test – 1	0.92	12 (3)	12 (63)	1027
Trail making test – 2	0.45	12 (63)	12 (63)	951
Trail making test – 3	0.32	12 (3)	12 (2)	848
Trail making test – 5	0.53	13 (1)	13 (2)	820
CWIT^a – 1	0.72	10 (63)	9 (3)	904
CWIT^a – 2	0.77	11 (3)	11 (3)	914
WAIS-IV^2 Coding	0.45	11 (63)	11 (2)	926
Attention and concentration
Ruff 2 & 7^3 Total speed^Ɨ, mean (SD)	0.24	58 (10)	55 (11)	t(96) = 1.2
Ruff 2 & 7^3 Total accuracy	0.61	49.5 (10)	49 (8)	898
Learning and memory
CVLT – II^4 Total learning ^Ɨ, mean (SD)	0.06	61 (11)	55 (14)	t(105) = 1.9
CVLT – II^4 Short Delay Free Recall	0.04	60 (14)	55 (19)	782
CVLT – II^4 Long Delay Free Recall	0.06	60 (14)	55 (14)	823
Prospective memory
MIST Total PMT^5	0.71	69 (62)	73 (32)	953
Executive functions
Trail making test – 4	0.19	11 (3)	11 (63)	863
CWIT^a – 3	0.01	11 (3)	12.5 (3)	631
CWIT^a – 4	0.07	11 (63)	12 (3)	699
Verbal abilities
WAIS-IV^2 Vocabulary	0.17	10 (3)	10 (3)	857
WAIS-IV^2 Similarities	0.60	12 (4)	11 (4)	995
Visuospatial abilities
WAIS-IV^2 Matrix Reasoning	0.87	13 (5.5)	13 (4)	1058
WAIS-IV^2 Block Design	0.53	11 (3.5)	11 (3)	994
General Ability Index (GAI)	0.41	114 (16.5)	112 (23)	916

^aColor Word Interference Test, ²Wechler Adult Intelligence Scale 4^th Edition, ³The Ruff 2 & 7 Selective Attention Test, ⁴Verbal Learning Test – II, ⁵Memory for Intentions Test – Prospective Memory Test, ^ƗT-test.