Cognitive dysfunction in young men following head injury in childhood and adolescence: a population study

Abstract

Objectives: To examine the prevalence of cognitive dysfunction among young men who had suffered a head injury during childhood or adolescence, in particular focusing upon the effects of age and the severity of the injury. Methods: By cross linkage of Danish national registers for hospital admissions and the draft board, 3091 young men were identified who had been injured before age 18 and tested at age 18 or shortly thereafter: 970 had suffered a single concussion and were in hospital for one day only; 521 had two concussions at separate times and were in hospital for one day only on each occasion; 961 had a cranial fracture; and 639 had a cerebral lesion. For all of these, scores on the draft board's cognitive screening test were obtained, dichotomised as dysfunctional or non-dysfunctional. Prevalences of dysfunctional scores were compared with population base rates (about 20% of all Danish men appearing before the draft board had a score classified as dysfunctional). Results: For young men who had suffered a single concussion, cranial fracture, or cerebral lesion before 12 years of age, resulting in less than 12 days of hospital admission (n = 376), rates of cognitive dysfunction did not exceed those in the general population (odds ratios < 1.4, NS), but the odds ratios became significant and > 1.4 where the injury occurred after age 11. For those with a cerebral lesion resulting in over 11 days of hospital admission (n = 263), all odds ratios were significant and > 2.0, irrespective of age at injury. For cases of two concussions, all odds ratios were > 1.4 but were not significant for all age groupings. Conclusions: For milder forms of single head injury before age 12 there is no evidence of enduring cognitive dysfunction. The apparent effect at later ages may reflect predisposing psychosocial factors. For more serious injury, and for cases with two concussions, the effect is marked and not clearly related to age. For the former, this suggests enduring neurological effects of the injury; for the latter, where the effect is unrelated to time between injuries, predisposing factors may again play a role.

Repeated concussion among U.S. military personnel during Operation Iraqi Freedom

“…A recent study among professional football players found no association of time between repeat concussions and number of reported postconcussive symptoms [21]. Another study found similar results, though time between events was analyzed as a dichotomous variable of less than or greater than 6 months, which may have diluted any association [27]. One recent study found evidence of a mediating effect of time, but this study used electroencephalography to directly measure brain function [14].…”

3: A Study of Outcomes Following Head Injury Among Children and Young Adults in Full-Time Education

“…A longitudinal study in Denmark followed a birth cohort of young men to look at the effect of age at injury, and severity of injury, on a draft board"s compulsory cognitive functioning test, taken at the age of eighteen years [16]. The results suggested that a single head injury after eleven years of age, not requiring admission to hospital for more than one day, was linked with higher failure rate in the cognitive test when compared to the non-injured cohort.…”

“…It is widely recognised that a proportion of "minor" head injury patients will continue to suffer disability and symptoms beyond six months after their injury [11,16,51,87,88], whereas most physiological effects would be expected to have subsided within three months [67,83].…”

Diagnosis and Correction of Cognitive Disorders in Children With Traumatic Brain Injury Sequelae

“…It has been proved that adolescents and adults recover neurological functions after sever TBIs with equal effectiveness [34]. Other scientists assume that adolescents are capable of a relatively fast recovery of motor and sensory functions even after severe TBI (just like children) [39]. Other neurological disorders commonly include speech and sight impairment and sleep disorders [17,19,21].…”

“…According to the ICD-10, cognitive disorders after TBIs are classified in the framework of post-concussional syndrome (F07.2). There are three levels of post-traumatic cognitive disorders [14,16,39]: 1) traumatic encephalasthenia (dynamic functional disorders);…”