Looking at nationwide databases in Sweden from 1964 to 2012, the authors of this new study found that TBIs may raise the risk of a dementia diagnosis for as long as 30 years after the injury. These researchers noted that the link between TBIs and dementia has been studied, but the effects of a TBI over time were not well-understood.
During the year following a TBI, patients' risk of being diagnosed with dementia increased by four to six times, this study found. After a year, the raised risk appeared to decline rapidly, but it was still significant 30 years later.
In an average follow-up period of 15 years, the overall risk of dementia among patients with TBIs was 80 percent higher than it was among patients who did not have a brain injury, according to these researchers.
Among the hundreds of thousands of study participants, those who had multiple TBIs or particularly severe ones were more likely to develop dementia. However, the study authors pointed out that having dementia could increase the risk for subsequent TBIs, so they can't use their findings to prove cause and effect.
If you are concerned about your risk for dementia, speak with your health care provider.
This study was published in the journal PLOS Medicine.
The Swedish Research Council funded this research. The study authors disclosed no potential conflicts of interest.