Who is Most Vulnerable for Long COVID and Can These Factors be Mitigated?

Long COVID or post−COVID-19 condition (PCC) has been a multifactorial health ailment that has been mysterious in nature and leaves more questions than answers for clinicians and patients. There is great variability in the way it presents, the length of the condition, and who is more likely to get it.

A new study, however, finds having certain risk factors were associated with increased chances to contract Long COVID.

The investigators did a meta-analysis of 41 studies, which included 860,783 patients, and they found that the following risk factors were significantly associated with developing PCC:

• being of the female sex
• being older
• having a higher body mass index
• being a smoker
• having preexisting comorbidities
• previous hospitalization or ICU admission

However, one variable helped decrease the chances of developing the condition: vaccination. “Meta-analysis of these showed that individuals who had been vaccinated with 2 doses (in all included studies) had a 40% lower risk of developing PCC (OR, 0.57; 95% CI, 0.43 to 0.76; I2 = 91%,” the authors wrote. There were 4 studies with a total of 249,788 patients that were evaluated for the effect of vaccination and the risk of developing Long COVID.

The investigators also noted that their findings concurred with a recent report from the United Kingdom Office of National Statistics that found a 42% lower risk of PCC after 2 doses of a COVID-19 vaccine. "Importantly, emerging evidence suggests that vaccination reduces the risk of PCC and its sequelae even in individuals with other risk factors, such as older age or high BMI,” they wrote.

The results were published in JAMA Internal Medicine.

Some of the preexisting comorbidities associated with increased risk of Long COVID included:

• Anxiety and/or depression
• Asthma
• COPD
• Diabetes
• Ischemic heart disease
• Immunosuppression

In addition, those patients who needed hospitalization or ICU care during the acute phase of COVID-19 infection were found to have more than twice the risk of developing PCC the study's authors wrote.

The investigators noted some limitations such as considerable statistical heterogeneity. “Large meta-epidemiologic studies have shown that studies at high risk of bias tend to overestimate the strength of associations. In addition, all the included studies were observational. Consequently, the results of the performed meta-analyses were based on observational data,” they noted.