Older individuals may have a more difficult time recovering from concussion, according to a new study published online in the journal Radiology.
Mild traumatic brain injury (MTBI), or concussion, accounts for 75 percent of all TBI and represents an important public health problem. Difficulty in working memory is frequently reported in patients after concussion. However, neuropsychological tests, computed tomography (CT) and conventional magnetic resonance imaging (MRI) generally fail to reveal abnormal findings in these patients. Functional MRI (fMRI) has been increasingly used in assessing patients with MTBI.
“Old age has been recognized as an independent predictor of worse outcome from concussion, but most previous studies were performed on younger adults,” said the study’s lead author, David Yen-Ting Chen, M.D., from the Department of Radiology at Shuang-Ho Hospital, Taipei Medical University, in New Taipei City, Taiwan.
For this study, Dr. Chen and colleagues used fMRI to evaluate the effect of age on working memory performance and functional activation in the brain after MTBI. The researchers performed fMRI exams on 13 young adults (21-30 years old) and 13 older adults (51-68 years old) with MTBI and 26 age- and gender-matched controls. The first fMRI scan was performed within one month post-injury. A follow-up scan was performed six weeks after the first exam. The researchers then analyzed post-concussion symptoms, neuropsychological test results and working memory activity in both groups.
The analysis revealed that while performing working memory tasks, the young patients with concussion had initial activation that was greater than normal, known as hyperactivation, compared to young controls in the right precuneus and right inferior parietal gyrus of the brain, whereas the older patients had hypoactivation (less than normal) compared to older controls in the right precuneus and right inferior frontal gyrus.
In comparing the patients in initial and follow-up study, the young patients had significantly reduced post-concussion symptom score at follow-up than at the time of the initial exam, but no significant change of the post-concussion symptom score was observed in the older patients, who also showed persistent hypoactivation.
“Taken together, these findings provide evidence for differential neural plasticity across different ages, with potential prognostic and therapeutic implications,” said the study’s co-author, Ying-Chi Tseng, M.D., from Shuang-Ho Hospital. “The results suggest that MTBI might cause a more profound and lasting effect in older patients.”
The researchers hope that these findings might eventually lead to the development of separate management strategies for different age groups following concussion.
About this concussion and neurology research
Funding: This research was supported by National Science Council, Taiwan, Taipei Medical University.
Source: Linda Brooks – RSNA Image Source: The image is in the public domain Original Research:Abstract for “Effect of Age on Working Memory Performance and Cerebral Activation after Mild Traumatic Brain Injury: A Functional MR Imaging Study” by David Yen-Ting Chen, Hui-Ling Hsu, Ying-Sheng Kuo, Changwei Wesley Wu, Wen-Ta Chiu, Feng-Xian Yan, Wei-Shuan Wang, Chi-Jen Chen, and Ying-Chi Tseng in Radiology. Published online October 6 2015 doi:10.1148/radiol.2015150612
“Effect of Age on Working Memory Performance and Cerebral Activation after Mild Traumatic Brain Injury: A Functional MR Imaging Study
Purpose To evaluate the age effect on working memory (WM) performance and functional activation after mild traumatic brain injury (MTBI).
Materials and Methods This study was approved by the local research ethics committee. All participants provided written informed consent. N-back WM cerebral activation was assessed with functional magnetic resonance (MR) imaging in 13 younger (mean age, 26.2 years ± 2.9; range, 21–30 years) and 13 older (mean age, 57.8 years ± 6.6; range, 51–68 years) patients with MTBI and 26 age- and sex-matched control subjects. Two functional MR images were obtained within 1 month after injury and 6 weeks after the initial study. Group comparison and regression analysis were performed among postconcussion symptoms, neuropsychologic tests, and WM activity in both groups.
Results In younger patients, initial hyperactivation was seen in the right precuneus and right inferior parietal gyrus (P = .047 and P = .025, respectively) in two-back greater than one-back conditions compared with younger control subjects, whereas in older patients, hypoactivation was seen in the right precuneus and right inferior frontal gyrus (P = .013 and P =.019, respectively) compared with older control subjects. Increased WM activity was associated with increased postconcussion symptoms in the right precuneus (r = 0.57; P = .026) and right inferior frontal gyrus (r = 0.60; P = .019) and poor WM performance in the right precuneus (r = −0.55; P = .027) in younger patients at initial studies but not in older patients. At follow-up examinations, partial recovery of activation pattern and decreased postconcussion symptoms (P = .04) were observed in younger patients but not in older patients.
Conclusion The different manifestations of postconcussion symptoms at functional MR imaging between younger and older patients confirmed the important role of age in the activation, modulation, and allocation of WM processing resources after MTBI. These findings also supported that younger patients have better neural plasticity and clinical recovery than do older patients.
“Effect of Age on Working Memory Performance and Cerebral Activation after Mild Traumatic Brain Injury: A Functional MR Imaging Study” by David Yen-Ting Chen, Hui-Ling Hsu, Ying-Sheng Kuo, Changwei Wesley Wu, Wen-Ta Chiu, Feng-Xian Yan, Wei-Shuan Wang, Chi-Jen Chen, and Ying-Chi Tseng in Radiology. Published online October 6 2015 doi:10.1148/radiol.2015150612