Local Hospitals Are Seeing an Uptick in Amnesia Cases. Why?

MRI image via istock.com/haydenbird

A strange medical phenomenon is raising new questions about the consequences of substance use.

Boston-area doctors have seen an abnormally high 14 cases of amnesia—partial or total memory loss—since 2012, according to a report from the CDC. Unusually, these cases did not have a clear catalyst, such as a stroke or traumatic brain injury, and each patient showed reduced blood flow to the hippocampus, the part of the brain that controls emotion and long-term memory.

The common thread may be substance abuse, according to preliminary analysis.

Thirteen of the 14 victims reported a history of substance abuse, and the 14th tested positive for drugs at the time of examination. Twelve of the 14 had a history of opioid use, and eight tested positive for opioids at the time of intake. Some patients also tested positive for cocaine and other drugs.

Given that pattern and the patients’ relative youth—all were between the ages of 19 and 52—substance abuse, and particularly opioid use, seems to be a factor in these cases, though no conclusions have been drawn yet.

“What we’re concerned about is maybe a contaminant or something else added to the drug might be triggering this,” Alfred DeMaria, state epidemiologist at the Massachusetts Department of Public Health (MDPH) and an author of the CDC report, told Stat. “Traditionally there’s no evidence that the drugs themselves can do this.”

A neurologist at Lahey Hospital and Medical Center alerted public health officials to the problem in November 2015, when he reported that Lahey alone had seen four cases during the prior three years. After that, the MDPH asked other medical centers to look for similar cases observed since 2012. Ten new patients joined the dataset after that call to action.

Some patients, Stat reports, were brought into hospitals during an overdose; others simply began to show confusion or memory loss. Some of the victims have regained cognitive function, while others haven’t.

Fourteen cases is unusual unto itself, but public health officials are concerned the pattern won’t stop here.

“Considering 14 cases in four years, we’re worried we’re going to find more cases,” DeMaria told Stat.