If you’re smoking or you have diabetes, you might want to take extra care of your brain. The two seemingly unrelated issues have a similar effect: they help create calcifications in an area of the brain responsible for memory formation.

Axial and coronal CT images in 88-year-old woman show mild hippocampal calcification (white arrowheads). Image credits: Radiological Society of North America.

Researchers have now known that areas of the hippocampus can become calcified with increasing age. It seems fairly straightforward that this causes significant damage, but until now, the extent of that damage hasn’t been thoroughly assessed. This is what the new study set out to do.

“We know that calcifications in the hippocampus are common, especially with increasing age,” said the study’s lead author, Esther J.M. de Brouwer, M.D., a geriatrician at the University Medical Center in Utrecht, the Netherlands. “However, we did not know if calcifications in the hippocampus related to cognitive function.”

The leading hypothesis was that these abnormal buildups of calcium can lead to cognitive deterioration, but this connection has not been definitively demonstrated. Thankfully, modern imaging techniques give researchers a way to monitor and connect these processes. Thus, de Brouwer and colleagues were able to show that indeed, this was the case.

Particularly, a method called multiplanar brain CT enables researchers to see these brain calcifications and distinguish them from similar processes in other areas.

“A multiplanar CT scan makes it possible to see the hippocampus in different anatomical planes; for example, from top to bottom, right to left and front to back,” Dr. de Brouwer said. “Before multiplanar CT scans, hippocampal calcifications were often mistaken for choroid plexus calcifications. So with multiplanar CT scans, hippocampal calcifications are better distinguished from calcifications in other areas.”

Interestingly, although the study was not designed to do this, it also highlighted some risk factors for brain calcification. Two stood out: diabetes and smoking.

Diabetes and smoking are often intertwined and can have devastating consequences, especially when working together. So if you’re suffering from diabetes, quitting smoking should be on the top of your to-do list. In this case, their effect seems to be so strong that it was detected even though researchers weren’t particularly looking for it.

“We do think that smoking and diabetes are risk factors,” Dr. de Brouwer said. “In a recent histopathology study, hippocampal calcifications were found to be a manifestation of vascular disease. It is well known that smoking and diabetes are risk factors for cardiovascular disease. It is, therefore, likely that smoking and diabetes are risk factors for hippocampal calcifications.”

The study “Hippocampal Calcifications: Risk Factors and Association with Cognitive Function” has been published in the journal Radiology.