Usually, this collection has a traumatic etiology.
Chronic subdural hematoma (CSDH) is an increasingly common subtype of head injury, especially in the elderly population.
It is one of the most frequent reasons for cranial neurosurgical consultation and a significant public health problem. 4).
The medium age of patients with chronic subdural haematoma is of 63 years old. Due to the fact that the population continues to get old, it is expected that in 2030, its incidence will double 5) 6) 7) 8).
CSDH is projected to become the most common cranial neurosurgical condition among adults by the year 2030 9).
During the seven year period 1967-1973 a total of 64 residents of the City of Helsinki were diagnosed as having chronic subdural haematomas. Forty of the patients were diagnosed during life at the Departments of Neurology and Neurosurgery, University of Helsinki, and treated surgically. Twenty four were diagnosed at autopsy at the Department of Forensic Medicine, University of Helsinki, at which the autopsies in virtually all cases of subdural haematoma in Helsinki are performed. The total of 64 cases gives an incidence of 1.72/100,000/year in the average population, the incidence increasing steeply with advancing age up to 7.35/100,000/year in the age groups 70-79 years 10).
In this a study, using data of the Miyagi Traumatic Head Injury Registry Project.
From January 2005 to December 2007, 1,445 patients with CSDH were registered in the project (M:F=1,021:424, mean age 71.2±12.8 y.o.). Using these patient's records, the incidence of CSDH was investigated, as well as causes of head injury, severity, and outcome.
The overall incidence of CSDH was 20.6/100,000/year, with 76.5 in the age group of 70-79 y.o. and 127.1 in the over 80 y.o. group. Ground level fall was the most frequent cause of trauma in the elderly, in contrast to traffic accident, which was the most frequent cause in the younger generation. Compared to the younger generation, neurological condition was severer in the elderly at the time of admission, and the outcome was poorer at the time of discharge.
Compared to previous reports, this study demonstrates a marked increase in the incidence of CSDH. Not only population aging but also current medical trends (such as increases of the elderly patients who receive hemodialysis, anticoagulant, and/or antiplatelet therapy) may influence the increase of CSDH incidence 11).
A steady increase in the incidence of CSDH has been also observed in developing countries due to the rise in life expectancy 12).
CSDHs occurred more frequently on the left side. The anatomical asymmetry of the cranium influences the left predilection of CSDH 13).