How Short is Long COVID

The British Medical Journal (BMJ) today published a peer-reviewed observational study conducted in Israel that indicates people diagnosed with Long Covid may experience a shorter than the expected duration.

These new insights suggest that, although the Long Covid phenomenon has been discussed since the beginning of the pandemic in 2020, the vast majority of mild cases do not suffer long-term illnesses, say the researchers.

Long Covid has been defined as symptoms persisting or new symptoms appearing more than four weeks after the initial infection.

But the clinical effects of Long Covid one year after mild infection and their association with age, sex, coronavirus variants, and vaccination status remain unclear.

This BMJ study suggests that patients with Covid-19 are at risk for a small number of health outcomes, most of which are resolved within a year from diagnosis.

In particular, Covid-19-vaccinated people were at lower risk of breathing difficulties when compared with unvaccinated people.

The BMJ stated in a press release on January 11, 2023, most symptoms or conditions that develop after mild Covid-19 infection lingers for several months but return to normal within a year.

To address this debate, these researchers compared the health of uninfected individuals with those who had recovered from mild Covid-19 for a year after infection.

They used electronic records of a large public healthcare organization in Israel, in which almost two million members were tested between March 2020 and October 2021.

Over seventy Long Covid conditions were analyzed in a group of infected and matched uninfected members (average age 25 years; 51% female), as well as vaccination status. They excluded patients admitted to hospitals with more serious illnesses to ensure only mild disease was assessed.

Covid-19 infections were significantly associated with increased risks of several conditions, including loss of smell and taste, concentration and memory impairment, breathing difficulties, weakness, palpitations, streptococcal tonsillitis, and dizziness in both early and late time periods.

While hair loss, chest pain, cough, muscle aches, and pains and respiratory disorders resolved in the late period.

The overall burden of conditions after infection across the 12-month study period was highest for breathing difficulties, appearing in five of the six age groups and remained persistent throughout the first year post-infection. 

For example, compared with non-infected people, mild Covid-19 infection was associated with a 4.5-fold higher risk of smell and taste loss in the early period and an almost 3-fold higher risk in the late period. 

Male and female patients showed minor differences, and children had fewer outcomes than adults during the early phase of covid-19, which primarily resolved in the late period.

Most importantly, children had fewer outcomes, primarily resolved in the late period.

"Our study suggests that mild Covid-19 patients are at risk for a small number of health outcomes, and most of them are resolved within a year from diagnosis," wrote these researchers.

"Importantly, the risk for lingering dyspnoea was reduced in vaccinated patients with breakthrough infection compared with unvaccinated people, while risks of all other outcomes were comparable," they added.

The researchers point to some study limitations, such as incomplete measurement within medical records. And they can't rule out the possibility that Covid-19 patients may use healthcare services more frequently, resulting in higher reporting and increased screening for potential Covid-related outcomes in these patients.

Additional observations include that patients with Covid-19 had more blood tests because of their illness.

This could lead to a significant false association in conditions such as fatty liver, which is highly prevalent yet asymptomatic and usually discovered by liver enzyme abnormalities in blood tests.

A second potential bias they observed was in the reports of lymphadenopathy, which was reported to be a side effect of the BNT162b2 vaccine.

No industry conflicts of interest were disclosed by these researchers.

Note: In the U.S., the Centers for Disease Control and Prevention stated in November 202 no test determines if your symptoms or condition is due to COVID-19. Therefore, post-COVID conditions are not one illness.

Healthcare providers consider a diagnosis of post-COVID conditions based on your health history, including if you had a diagnosis of COVID-19 either by a positive test or by symptoms or exposure, as well as doing a health examination.