It's known that certain chronic health conditions up the odds of death from COVID-19. Now, new research identifies another risk factor.
Shorter telomeres are associated with an increased likelihood of death from COVID-19, particularly in older women, researchers say.
Telomeres are protective caps on the end of chromosomes (DNA) that shorten with age. Previous research has linked shorter telomeres with a number of age-related diseases, including cancer and osteoarthritis, and a higher risk of infections.
"Our findings implicate telomere length in COVID-19 mortality and highlight its potential as a predictor of death and severe outcome, particularly in older women," said study co-author Ana Virseda-Berdices, of Health Institute Carlos III in Madrid, Spain.
Virseda-Berdices and colleagues examined how telomere length affects COVID-19 severity. The study included more than 600 adults hospitalized with COVID during the first wave of the pandemic, March to September 2020. Telomere length was measured in patient blood samples taken within 20 days of COVID diagnosis or hospitalization.
The 533 patients who survived had an average age of 67, compared with an average age of 78 among the 75 patients who died from COVID.
Among all patients, shorter telomeres were significantly associated with a higher risk death from COVID-19 at 30 and 90 days after hospital discharge.
Further analyses by age and gender showed that longer telomeres were associated with a 70% lower risk of dying from COVID in all women at 30 days, and a 76% reduced risk of dying from the disease at 90 days.
In women 65 and older, longer telomeres were associated with a 78% lower risk of death from COVID-19 at 30 days, and 81% reduced risk at 90 days.
There were no significant differences in telomere length between men who survived COVID-19 and those who died of the disease, according to the study.
The findings were scheduled for presentation this week at the European Congress of Clinical Microbiology and Infectious Diseases, in Lisbon, Portugal. The meeting ends Tuesday.
"While we do not know the reasons for the strong association found in women, it's possible that the lack of association between telomere length and COVID-19 mortality in men could be due to increased comorbidities and risk factors in men that masked the effect," Virseda-Berdices said in a meeting news release.
"Female patients tend to present with less severe disease and are more likely to survive COVID-19, probably due to fewer lifestyle risk factors and comorbidities than men. Besides aging, telomere dysfunction is also associated with smoking, poor diet, higher body mass index and other factors that promote oxidative stress, chronic inflammation and cancer," Virseda-Berdices added.
The study was observational and does not prove cause and effect, the researchers noted. Research presented at meetings is usually considered preliminary until published in a peer-reviewed medical journal.
There's more on telomeres at the U.S. National Human Genome Research Institute.
SOURCE: European Congress of Clinical Microbiology and Infectious Diseases, news release, April 21, 2022