Insurers could track long COVID through loss-of-smell data: study

As health plans wrestle with what to do about COVID-19 coverage going forward, a recent study in JAMA Network Open concludes that patients suffering from a loss of the sense of smell might be more susceptible to exhibiting symptoms of long COVID for longer periods of time.

“Our results highlight the need to continue monitoring the rate of recovery of olfactory function among individuals with long COVID to evaluate whether it is a chronic or permanent sequela,” concluded researchers with Pará State University in Belém in the Amazon region of Brazil.

They argued that their results show loss of a sense of smell is one of the more common symptoms of COVID-19. The study was published last Thursday.

The study states: “We observed in this cohort that patients with olfactory dysfunction may experience persistent severe hyposmia or anosmia more than one year from the onset of symptoms, suggesting the possibility of permanent sequelae.”

Hyposmia is a decreased ability to detect odors through the nose; anosmia is also a loss of the sense of smell that could be triggered by head injury or infection.

For this study, researchers collected data from 219 patients diagnosed with long COVID between Sept. 9, 2020, and Oct. 20, 2021. What they found focuses on the original, or so-called wild, form of the virus that emerged in early 2020, and not variants such as delta or omnicron.

Patients who experienced loss of smell “had a significantly longer duration of long COVID symptoms than those in the normosmia group,” the study found.

The Centers for Disease Control and Prevention (CDC) lists about 20 symptoms of long COVID under the categories of general symptoms, respiratory and heart symptoms, neurological symptoms, digestive symptoms and other.  

Lucy Johns, a healthcare consultant, said that one cannot read too much into the findings of a single study. However, health plans need to prepare, said Johns, who is the consumer representative at Carequality, a company that sells advice on how to better facilitate communication between healthcare systems.

“The health insurance industry could jump-start understanding of this shape-shifting virus,” Johns told Fierce Healthcare. “It knows what happens when warning signs of disease and disability are ignored: Things only get worse. It is clearly in its financial interest to follow the effects of COVID over the next few years, certainly for their own insured. But since COVID overwhelmed personal and health delivery resources early on, COVID can’t be conceived as simply a personal health issue whose long effects will start showing up in provider billings. COVID is a public health issue.”

Richard Stefanacci, chief medical officer at the Jefferson College of Population Health at Thomas Jefferson University, says that more research needs to be done before health insurance plans and employers can act decisively on long COVID.

“It is not yet clear the cost of long COVID, and, as a result, payers and employers have not placed this on their radar,” Stefancci told Fierce Healthcare. “I’d expect very shortly, two important facts getting defined—the cost of long COVID and the diagnostic criteria. Without these two elements, payers and employers can’t plan and manage appropriately.”

Stefanacci also thinks that there needs to be more investigation of possible links between long COVID and Alzheimer’s disease.

“In July of this year, researchers at the University of Chicago found that not only can a decline in sense of smell over time predict loss of cognitive function, loss of the sense of smell can also be a warning sign of structural changes in regions of the brain important in Alzheimer’s disease and dementia,” said Stefanacci.

“If the pathology of long COVID is similar to AD, it may follow similar diagnostic challenges and cost, as the costs with AD are typically caregiver or long-term care, which doesn’t typically affect payers and employers. As a result, long COVID may not impact payers and employers but rather be very costly to patients, their caregivers, and the state due to long-term care costs," Stefanacci told Fierce Healthcare.

In the JAMA Network Open study, to get their results, researchers used eight bottles, seven of which contained different levels of butanol alcohol dilutions in water; the eighth bottle contained distilled water only. “The odor identification test consisted of identification through inhalation of 8 common substances to be identified from a 16-item list,” the study found. Data were also gathered via a questionnaire. Example question: “In your opinion, did the olfactory dysfunction affect your hazard detection ability?”

The study found that “high recovery rates of persistent olfactory dysfunctions are expected within 1 year; however, despite our analyses occurring within this period, the group with olfactory dysfunction had long COVID for a significantly longer time than the group with normosmia, and most patients with olfactory dysfunction had severe dysfunction. Long periods of severe olfactory dysfunction are associated with worse diagnosis and risk of permanent sequelae.”

What sort of strain long COVID could put on the health system remains to be seen. However, it has already put a strain on the economy. In a recent Brookings Institute report, Harvard University economist David Cutler, Ph.D., estimated that 3.5 million people are out of work because of long COVID. That equates to $1 trillion in lost wages over five years, or about $200 billion a year.

Johns argued that the health insurance industry should coordinate its response with federal and state healthcare officials.

“For example, AHIP could call a meeting with the CDC to plan for monitoring, tracking, and treating long COVID symptoms,” said Johns. “The CDC is the U.S. leader for identifying and surveilling infectious diseases like COVID. Insurance companies in any state could take initiative to contact their state health departments for the same reason, to monitor, track, and treat long COVID. This approach should include offer to help fund this task, since most state health departments have been starved for decades and may not have the resources to follow Covid as new threats arise.”