A Bruise on the Brain is Fairly Common in Old Age

Older folk (over 75-ish) tend to bruise easily.  Often a bruise will appear without any obvious cause, such as a blow or a fall; and without the subject being under treatment with anticoagulants.  Whatever the reason, the bruise shows itself as a collection of blood that’s escaped from a blood vessel, and takes a long time to be broken down and removed.  If this happens in inside the skull, it’s likely to be a chronic subdural hematoma (CSDH).  The normal brain shrinkage that occurs with aging stretches and pulls on the veins linking the brain surface and the dura mater (the tough membrane that covers the brain), leading to a slow accumulation of blood over several days, which may fail to disappear on its own.  Surgery is the usual treatment option, as described in a study reported in the Journal of Neurosurgery.

The study intended to focus on the long-term survival of patients with CSDH, but it revealed other interesting information on the condition. Data were available on 209 cases of CT-diagnosed CSDH admitted over 8 years to the Allegheny General Hospital, Pittsburgh.  The patients’ average age was 80, and 63% of them were men; 22% of them were on anticoagulants.  Surgery (craniotomy, drainage, or burr holes) was done in 137 patients, while the other 72 were simply observed.

Burr holes seemed to be the most successful treatment in terms of 5-year survival.  There was 17% in-hospital mortality, with an average survival for the remaining discharged patients of 4.4 years.  Thus mortality climbed to 26% at 6 months and was 32% at one year follow-up.  This represents significantly greater mortality than that provided by matched actuarial figures.  The factors contributing to this excess mortality were advanced age and discharge to another nursing facility (as opposed to home).  There was no indication that the treatments used (including simple observation), or the size of the hematoma, or the use of anticoagulants influenced subsequent mortality.

To summarize, CSDH is a relatively common condition among the elderly, and short- term survival is fairly good, being largely independent of treatment.  However, there’s an increasing rate of long-term mortality, especially for older patients (80 years old and above) and in those who can’t be returned home.