The team also found lower red blood cell production or anemia in the female patients. This suggests that elevated levels of inflammatory factors in females with long Covid adversely affect their blood production, Elahi says. In addition, the researchers uncovered dysregulated sex hormones in the long Covid patients, finding reduced testosterone levels in affected women and decreased estrogen in male patients, as well as lower levels of the hormone cortisol in both.
The researchers reported that women with lower testosterone levels had higher levels of inflammation in their blood. Testosterone normally helps control inflammation, so reduced levels may make women more vulnerable to ongoing inflammatory responses, the researchers posit. Lower testosterone levels were also linked to symptoms such as brain fog, depression, pain and fatigue.
The findings suggest that hormone imbalances could play an important role in long Covid, particularly how it affects women, Elahi says.
These results are similar but not identical to what is found in idiopathic (of unknown cause) chronic fatigue syndrome, now referred to as myalgic encephalomyelitis/chronic fatigue syndrome or ME/CFS, which also disproportionately affects women. For example, anemia is not associated with chronic fatigue, but chronic inflammation is a characteristic.
The Elahi team’s findings are reinforced by another recent international study of more than 500 patients, which also reported anemia as a major biological underpinning of long Covid. Elahi plans to further verify his findings by testing potential treatments in mice that have long Covid, and he is seeking funding for a clinical trial. He proposes an individualized approach to treatment depending on each patient’s test results that might include anemia treatment, anti-inflammatory drugs and even sex hormones. He also intends to continue exploring similarities between the neurological symptoms of long Covid and those associated with HIV infection.
Source: University of Alberta