Two studies presented at the European Respiratory Society (ERS) virtual meeting should reassure asthma patients and their physicians about their risks from COVID-19.
On the one hand, “no evidence of excess deaths was directly attributed to asthma” in a study of Scottish data on hospital admissions and death certificates during the first COVID-19 wave in early 2020, said Steven Smith, MRCP, of Gartnavel General Hospital in Glasgow.
And on the other, analysis of asthma patients receiving biologic drugs in Greek clinics showed no overall increase in COVID infection rates relative to the general population through April of this year, reported Andriana Papaioannou, MD, PhD, of Attikon University Hospital in Athens.
These encouraging results come against a backdrop of worry about how patients with preexisting respiratory disease, who may also be taking immune-modulating drugs, would fare during the pandemic.
There were two concerning blips in the Greek data, however. Papaioannou’s group found that, among the 26 biologic-treated patients who did come down with COVID-19, nine needed hospitalization — a considerably higher proportion than among COVID patients in the general Greek population, she said.
More startling perhaps was that all nine of these patients needing inpatient care were taking mepolizumab (Nucala; of 16 COVID-infected patients on the therapy) while none of the nine patients on omalizumab (Xolair) with COVID infection required hospital admission (P=0.014). The sole COVID death in the cohort was in a mepolizumab patient. Mepolizumab was the drug of choice for 61% of the entire 591-patient cohort.
Common to both studies, too, was that women with asthma seemed to be at somewhat greater risk. Smith noted that, among the 81 COVID-19 deaths for which certificates listed asthma as “contributory,” 59% were in women, whereas women accounted for only 48% of the 2,361 COVID deaths unrelated to asthma (P=0.044).
In the Greek study, eight of the nine patients needing hospitalization were women, also very disproportionate, said Papaioannou.
Asked by ERS discussants to comment on that aspect of the studies, Papaioannou observed that severe asthma is generally more common in females. Neither her group’s analysis nor Smith’s sought to correlate the adverse outcomes with both gender and baseline asthma severity (in the Greek data, all patients had severe asthma as part of the study design).
Smith commented that he saw no easy explanation for the gender disparity.
His study examined hospitals admissions and deaths related to asthma during the first months of the pandemic as well as during the 5 previous years. A time-series graph of admissions from January 2015 to April 2020 showed a consistent pattern through 2019, with peaks in the winter and troughs in the summer. In 2020, however, admissions dipped to levels not even seen in the prior years.
That raised a question of whether asthma mortality would rise during the pandemic, with asthma sufferers avoiding treatment for exacerbations. This did not seem to be the case, Smith reported.
Although there was an enormous spike in April 2020 compared to previous years in deaths recorded in Scotland with asthma as an “underlying” or “contributory” cause — 130 versus less than 60 in every month back to 2015 — almost all of those were primarily from COVID, according to death certificates.
Deaths with asthma as an “underlying” cause showed no unusual increase in early 2020, indicating that a diagnosis of asthma did not seem to convey any new risk with COVID.
For the Greek study, Papaioannou and colleagues prospectively contacted 23 asthma clinics in the country for data on their patients with severe disease during March 2020 to April 2021. Physicians were encouraged to contact their patients regularly during the pandemic and to perform PCR testing on those with COVID-19 symptoms.
Median age for the 591 patients on biologics was 57 and about two-thirds were women. Median duration of biologic treatment was 27 months (IQR 13-40). Nearly all of the cohort were using either mepolizumab (61%) or omalizumab (37%); benralizumab (Fasenra) was not approved in Greece but 14 obtained it through special programs, Papaioannou explained.
One factor that may help explain why all the hospitalizations were in mepolizumab patients is the drug’s targeting of eosinophils, she said, adding that other studies have indicated that eosinophils are reduced during COVID-19. “The possibility that a biologic treatment which reduces eosinophils to increase the risk for more severe COVID has to be examined in further studies,” she urged.
One other finding that Papaioannou sought to highlight was that duration of biologic treatment did correlate significantly with COVID risk in the study. Among those who became infected, the median time on treatment was 12 months, versus 28 months for those who did not (P<0.001). She did not speculate on the reason for that, however.
Smith said he had no relevant financial interests. Papaioannou reported receiving fees from seven pharmaceutical companies active in asthma therapeutics.