Case study: COVID-19-induced hyposmia prevented migraines triggered by strong odors

CHICAGO — COVID-19-induced hyposmia eliminated odor-induced migraine headaches in an older adult, a case study presented at the 2022 American Neurological Association’s annual meeting showed.

Sunjeet K. Brar, BSc, a medical student at Aureus University School of Medicine, presented the case of a 63-year-old man with a history of strong odor-precipitating headaches, which were sudden-onset, throbbing, bifrontal, associated with blurred vision and photophobia, and lasted around 7 hours.

“He developed COVID-19 and lost his ability to smell,” Brar told Healio. “His migraines went away for the duration of the COVID-19 infection.”

However, once the man recovered from COVID-19 and regained his sense of smell, the headaches returned.

Brar referred to this phenomenon, which is widely described among neurological diseases, as “enantiopathy” — where one disease eliminates another disorder.

According to Brar, a CT scan of the man’s brain and sinuses was normal.

“There was a disconnect because of COVID, and the moment that [infection] went away, that connection was reattached, and [the headaches] ended up coming back,” Brar said.

Further research is needed, Brar said, and she and colleagues aim to conduct larger studies.