Diabetes, Hypertension Linked to COVID-19-Related Neurological Complications

Colbey Freeman, MD

This article was originally published on Diagnostic Imaging.

According to a new study, coronavirus disease 2019 (COVID-19) positive patients who had hypertension and type 2 diabetes were more likely to experience the neurological complications, including bleeding in the brain and stroke, that come with the virus.

Based on CT and MRI images, investigators from the Perelman School of Medicine at the University of Pennsylvania determined that these chronic conditions could play a role in which patients are impacted by more than just the hallmark lung inflammation that comes with viral infection.

“COVID-19’s effects extend far beyond the chest,” said lead study author Colbey W. Freeman, M.D., chief resident in the Penn Medicine radiology department. “While complications in the brain are rare, they are an increasingly reported and potentially devastating consequence of COVID-19 infection.”

Freeman’s team will present their findings during this year’s Radiological Society of North America (RSNA) annual meeting. 

In an effort to better understand how COVID-19 impacts the body, they examined head CT and/or MRI images for patients positive for the virus who presented to the University of Pennsylvania health system from January 2020-April 2020.

A total of 81 of the 1,357 COVID-19-positive patients who were admitted underwent a brain scan prompted by either altered mental state or focal neurological deficits, including speech and vision problems.

Based on the team’s analysis, 18 patients – slightly over 20% – had findings that were considered critical, such as strokes, brain bleeds, or blocked blood vessels. And, of that group, at least half also had a pre-existing history of high blood pressure or type 2 diabetes.

“COVID-19 is associated with neurological manifestations, and hypertension and type 2 diabetes mellitus are common in individuals who develop these manifestations,” Freeman said. “These populations may be at higher risk for neurologic complications and should be monitored closely.”

The team also found that two-thirds of the patients who had critical findings were African American, indicating COVID-19 positive patients in that minority group should be monitored more closely. And, among the entire group of 18 with emergent findings, three died while in the hospital, the team said.

Although this study revealed a role for high blood pressure and type 2 diabetes in the neurological impact of the virus, investigators still do not know exactly what causes those complications.

The mechanisms could be multi-factorial, and the generally accepted belief is that infection-associated inflammation is responsible, they said. In this study, in particular, they reported blood markers for inflammation were high in patients who had critical results.

“When your body is in an inflammatory state, it produces all these molecules called cytokines to help recruit the immune system to perform its function,” Freeman said. “Unfortunately, if cytokines are over-produced, the immune response actually starts doing damage.”

Using data from this study, the team is also looking at the how frequently COVID-19-positive patients on extracorporeal membrane oxygenation (ECMO) – a pump system that circulates and replenishes oxygen in the blood – experience neurological complications. Many patients included in this study required ECMO during hospitalization.

Future plans include a larger prospective study to investigate delayed, long-term, and chronic neurologic manifestations that have not currently been identified, but that might manifest later.

The study, "Diabetes, Hypertension May Increase Risk of COVID-19 Brain Complications," was published online by RSNA.