The risk for people with asthma and other chronic respiratory diseases of severe Covid-19 is not as high as had been feared at the start of the pandemic, say researchers from the University of Oxford.
Analysis of records from 8 million patients at 1,205 general practices in England found people with active asthma and severe asthma had 26% and 29% higher relative risks of hospital admission with Covid-19 and around 30% higher relative risk of admission to intensive care compared with matched patients with no underlying respiratory disease.
However, this is lower than suggested by data collected between January and April 2020, which showed that COPD was associated with a 50% increased risk of hospitalisation and 54% increased risk of death from Covid-19.
Furthermore, there was no evidence that asthma was associated with an increased absolute risk of death from Covid-19, and the risks appeared similar for all ethnicities, the researchers reported in The Lancet Respiratory Medicine.
In patients with interstitial lung disease, researchers found a 30–50% increased relative risk of developing severe Covid-19 requiring hospital admission or leading to death.
The researchers said while the results did show an increased risk for patients with respiratory conditions, it was far lower than some other risks including age, being male or having diabetes.
There had been concerns among some asthma patients that they were not on the priority list for vaccination.
Study leader Professor Paul Aveyard, a GP and professor of behavioural medicine said at the start of the pandemic the reasonable assumption had been that pre-existing respiratory disease would lead to an increased risk of serious Covid-19 which had caused a great deal of anxiety for people with conditions such as asthma or COPD.
‘While our results do show this group are at higher risk from developing severe Covid-19, when you put this into context with other known risk factors for hospitalisation, the relative risk for those with chronic respiratory disease are lower than the risks from being male or having diabetes, and are a small fraction of the everyday risk of death from any cause.’
He said a useful way to consider the risk was to think about it in terms of age as everyone understands that Covid-19 carries more risk the older you are.
‘In a person with asthma, it is equivalent to the risk for people without asthma who are three to five years older.
‘For people with COPD or interstitial lung disease, their risk would be equivalent to the risk for people without these conditions who are seven to eight years older.’
He said people with chronic asthma in particular can be reassured by the results which would be helpful for GPs to use in discussion with patients.
The study also looked at risks associated with the use of inhaled corticosteroids (ICS) where the evidence is very mixed and trials are ongoing.
They found use of ICS is not associated with substantial increased risk of severe Covid-19, but neither does it appear to be linked to reduced risk.
‘We’re just going to have to wait and see for the trials. We can’t say you must or mustn’t use inhaled steroids,’ he said.