Antidepressant Use Increases Head Injury Risk in Alzheimer's Disease Patients

While many patients with Alzheimer’s disease are prescribed antidepressants to treat their symptoms, a new study published by Alzheimer’s Research & Therapy found that these drugs may increase the risk of head injury and traumatic brain injury among this population.

Antidepressants have previously been linked to an increased risk of falls and fractures, but the authors reported that the risk of head injuries had not been studied.

Included in the analysis were 10,910 patients who used antidepressants and 21,820 patients who did not use the drugs. All patients had Alzheimer’s disease and participated in the MEDALZ study.

The investigators found that antidepressants were associated with a higher risk of head injuries during the first 30 days of use. These findings were observed to persist for up to 2 years after initiation, according to a study.

The findings were confirmed by the design of the study, which compared different time periods within the same patient. The authors report that this design eliminates potentially confounding factors.

However, the link between traumatic brain injury and antidepressants was not as clear compared with head injuries. The authors attribute this finding to a smaller number of brain injuries experienced by these patients, according to the study.

Additionally, the use of other psychotropic drugs was not found to be responsible for the link between antidepressants and head injuries in patients with Alzheimer’s disease.

Head injuries are more common among older patients than younger patients, likely due to falls. Since antidepressants have been observed to cause an increased risk of falls, the authors were not surprised to learn that these patients also have an increased risk of head injuries, according to the study.

"However, our findings give cause for concern because persons with Alzheimer's disease frequently use antidepressants, which have been considered a safer alternative to, for example, benzodiazepines," said senior researcher Heidi Taipale, PhD.

The authors report that it is likely these findings are applicable to older patients without Alzheimer’s disease as well; however, additional research is needed to confirm their hypothesis.

"Our study population consisted of persons diagnosed with Alzheimer's disease, but it is likely that the risk is similar also in other older persons without Alzheimer's disease,” Dr Taipale concluded. “This is something we will be studying in the future."