Men who are heavy drinkers and homeless for long periods of time have 400 times the number of head injuries as the general population, according to a new study by researchers who said they were shocked by their findings.
These men have 170 times as many severe head injuries as the general population and 300 times as many injuries that cause bleeding in the brain.
The study by Dr. Tomislav Svoboda, a family physician at St. Michael's Hospital, appears online in Emergency Medicine Journal.
The study also looked at head injuries in the general homeless population and among people who are vulnerably housed, meaning they live in crowded, unsafe or unaffordable housing or are in danger of becoming homeless. Both these groups had about 23 times the number of head injuries as the general population, but rates much lower than the chronically homeless.
Previous studies of head injuries among people who are homeless have been based on interviews. Dr. Svoboda, a researcher in the hospital's Centre for Research on Inner City Health, said his study is the first based on actual Emergency Department records over five years and the first to compare people who are homeless with the general population based on that data. They looked at all head injuries from slight concussions to brain hemorrhages,
"We were shocked by the number if head injuries," said Dr. Tomislav. "In medicine, we worry when something occurs two or three times more often in a particular patient group, but to talk about magnitudes of 300 or 400 is unheard of."
Dr. Svoboda also found the length of time between head injuries shortened as the number went up. The mean interval between head injuries was 231 days. That decreased by an average of 11.8 days with each subsequent head injury.