Post-traumatic hydrocephalus (PTH) and chronic subdural hematoma (cSDH) are well known complications of head injury. However, the incidences of these conditions are not clear in certain situations. Increased mortality in the acute phase of TBI is well established, and there is good evidence suggesting long-term mortality to be increased as well.
While the reasons behind increased acute phase mortality are at least mostly intuitive, factors affecting long-term mortality are not well understood. It is not clear whether the reduced long-term survival of patients with head and brain injuries is due to trauma or some pre-existing factors – e.g., pre-existing conditions or lifestyle factors – of these patients.
In his doctoral dissertation, Aaro Heinonen examined the incidences of surgically treated PTH and cSDH after head injury in a cohort of consecutive patients with head injuries from one university hospital’s emergency department. Additionally, long-term mortality and causes of death were compared between patients with head injuries and population controls.
Heinonen’s findings reveal that the incidence of surgically treated PTH among patients with traumatic head injuries of all severities was very low but not negligible, especially among patients who had undergone surgery because of the index head injury. The incidence of surgically treated cSDH after normal initial head computed tomography, among patients with traumatic head injuries, was extremely low.
The low incidence of surgically treated cSDH, even in patients on antithrombotic medication, supports the notion that routine follow-up imaging after normal initial head computed tomography is not indicated to exclude the development of cSDH. Additionally, Heinonen’s findings support the concept that cSDH is not a purely head trauma-related disease.
Long-term survival was reduced in patients with traumatic head injuries. During the ten-year follow-up, mortality rates for patients were almost two-fold when compared to controls. Increased mortality rates among patients stayed elevated up to five years post-injury.
A large part of the reduced survival was associated with patient characteristics rather than injury severity-related factors, but traumatic brain injury severity seemed to have its own additional effect on mortality. Unintentional and traumatic causes, even after excluding the index injuries, and alcohol-related causes of death were more common among patients with head injuries compared to controls.
“Our findings support the notion that routine follow-up imaging after normal initial head computed tomography is not indicated to exclude the development of cSDH. Cutting out unnecessary examinations can benefit patients and save health care costs,” Heinonen explains.
“The result that increased mortality was associated more with patient characteristics than injury severity-related factors encourage us to design and focus rehabilitation after head and brain injuries so that lifestyle factors and pre-existing conditions are taken more into consideration,” Heinonen adds.
Public defence on Wednesday 28 May
The doctoral dissertation of Lic. Med. Aaro Heinonen in the field of neurosurgery titled Delayed neurosurgical consequences and long-term mortality after head injury will be publicly examined at the Faculty of Medicine and Health Technology at Tampere University at 12 o’clock on Wednesday 28.5.2025 at Kauppi campus, Arvo building, auditorium F115 (Arvo Ylpön katu 34, Tampere). The opponent will be Professor Mikael von und zu Fraunberg from the University of Oulu. The Custos will be Docent Teemu Luoto from Tampere University.