Patients with low levels of vitamin D who had recovered from coronavirus are at greater risk of developing long COVID.
Post-COVID syndrome, also known as long COVID is a condition that affects some people after the initial illness.
These patients may experience health problems and wide-ranging symptoms that could last for more than 3 months.
Several studies suggest that the condition affects between 50 to 70 percent of hospitalised COVID-19 patients.
Some of these patients experience severe symptoms leading to intubation and mechanical ventilation.
Vitamin D deficiency has been suggested as a risk factor, but its impact on long COVID has not been checked before.
The study measured vitamin D levels in patients with COVID-19 at the beginning of their admission and 6 months after leaving hospital.
The results showed that patients with long COVID had lower levels of 25(OH) vitamin D than those who had fully recovered.
Lower 25(OH) vitamin D levels was observed more frequently in those patients with neurocognitive symptoms such as brain fog, confusion, poor concentration, and forgetfulness.
Professor Andrea Giustina, the study’s lead author, said:
“Previous studies on the role of vitamin D in long COVID were not conclusive mainly due to many confounding factors.
The highly-controlled nature of our study helps us better understand the role of vitamin D deficiency in long COVID, and establish that there is likely a link between vitamin D deficiency and long COVID.”
The next step for the research team is to find out whether vitamin D supplements can lower the odds of post COVID-19 syndrome.
Professor Giustina said:
“Our study shows that COVID-19 patients with low vitamin D levels are more likely to develop long COVID but it is not yet known whether vitamin D supplements could improve the symptoms or reduce this risk altogether.”
- Brain fog, headache and numbness are the most common neurological symptoms of long COVID.
- Difficulties with memory and learning are signs of vitamin D deficiency.
- Vitamin D deficiency is linked to depressive symptoms and more negative thoughts.
- Long COVID: most common symptoms & time to recovery.
The study was published in The Journal of Clinical Endocrinology & Metabolism (Filippo et al., 2023).