Acute asthma admissions sharply declined during lockdowns as air quality improved, study reveals

9th February 2024

Reduced pollution levels and better air quality during the Covid-19 pandemic lockdowns strongly correlated with lower rates of acute asthma care provision, according to new research led by the University of Birmingham.

The retrospective time-series study, published in the BMJ Open, investigated the link between acute asthma hospital admissions and specific air pollutant levels in four Oxford postcodes during the national lockdowns of March to June and November to December 2020.

For adult residents, acute asthma admissions fell from 78 per 100,000 residents in 2015-19, to 46 per 100,000 residents in 2020 – a reduction of 41%.

This reduction in acute asthma care coincided with levels of air pollution falling significantly. Different pollutants dropped by 18-33% when compared to average values for the previous five-year period.

For example, nitrogen dioxide (NO₂) reduced by 26.7% from a 2015-19 average of 14.6 μg m-3 to 10.7 μg m-3 in 2020.

Fine particulate matter (PM_2.5) saw a reduction of 33.5% from 10.1 μg m-3 in 2015-19 to 6.7 μg m-3 in 2020, and PM₁₀ reduced by 18.6% from 13.2 μg m-3 in 2015-19 to 10.8 μg m-3 in 2020.

‘Large-scale measures to improve air quality have potential to protect vulnerable people living with chronic asthma in urban areas,’ the authors concluded.

Commenting on the ‘unique situation’ of temporary air quality improvement, Dr Suzanne Bartington, clinical associate professor of environmental health at the University of Birmingham and lead author of the study, said: ‘The results of air pollution levels falling may have had an impact on the number of severe asthma cases that need acute hospital care, with 41% fewer hospital stays compared to the previous five-year average.

‘Furthermore, we also identified a 4% increase in risk of asthma hospital admissions for every 1 μg m-3 increase in mean monthly NO₂, and an approximately 3% increase in risk for every 1 μg m-3 increase in mean monthly PM2.5 levels.

‘This is an important study to help us better understand how demand for NHS inpatient care may change when air quality is improved.’

The research team was supported by the University of Oxford, Oxfordshire County and City Councils and the then Oxfordshire Clinical Commissioning Group.

Commenting on the results, Councillor Nathan Ley, Oxfordshire County Council’s cabinet member for public health, inequalities and community safety, said: ‘We must now use what we have learned, thanks to this research with our partners, to improve our environment, in line with the Clean Air Strategy which we launched last year.

‘Elevated levels of NO₂, PM_2.5 and PM₁₀ contribute towards heart disease, chronic lung disease, cancers, preterm births, and many other avoidable events. The vision of Oxfordshire County Council to tackle this issue remains clear. We must continue to use all the tools at our disposal to lead the country, clean up our air and save lives.’

Earlier this week, the European Respiratory Society (ERS) warned of rising respiratory diseases, such as asthma, as well as premature death without urgent action on air quality.

This followed the ERS consensus statement on climate change and respiratory health, published in September 2023, which highlighted the damaging effects of air pollution on health and global warming.

Study reveals significant increase in hospital admissions for COPD and asthma

19th February 2023

Hospital admissions in the UK for COPD and asthma significantly increased over the last 21 years despite an increase in prescribed treatments

A study analysing hospital admissions for both chronic obstructive pulmonary disease (COPD) and asthma from 1999 to 2020, has revealed a significant increase for both conditions despite a considerable increase in prescribed treatments for these diseases.

Both COPD and asthma are common respiratory diseases. In a recent global systematic review it was estimated that some 391·9 million people had COPD in 2019 and the World Health Organization (WHO) estimates than in 2019, there were 3.23 million global deaths from COPD. Asthma also affects a huge number of people and WHO estimated that in 2019, the disease affected some 262 million people across the world and led to 455,000 deaths. With both diseases leading to a considerable number of deaths, in the present study, a team of Saudi Arabian researchers examined the trends in hospital admissions and which could result in death, for both COPD and asthma between 1999 and 2020. The researchers extracted information from the hospital episode statistics database in England and the corresponding database was Wales. In addition to hospital admissions data, the team also collected information on COPD and asthma-related medicines prescribed between 2004 and 2020.

Hospital admissions for COPD and asthma

The total annual number of admissions for the two conditions rose by 82.2% between 1999 and 2020 which represented a 59.1% increase in the hospital admission rate over this period of time (p < 0.05).

The most common reason for COPD admission (38.7%) was in combination with an acute lower respiratory tract infection and which increased by 198.5% between 1999 and 2020. In contrast, acute exacerbations of COPD alone, accounted for a quarter of admissions (25.5%) and this rate had actually reduced by 4.8% between 1999 and 2020. As with COPD, asthma additions also increased by 46.1% over the 21-year period.

Just over a third (34.7%) of COPD and asthma admissions occurred in those age 75 years and older with just under a quarter (23.5%) in those aged 15 – 59 years. Interestingly, slightly more than half (53.8%) of admissions for both conditions occurred in women.

When looking at prescriptions, the researched observed a 42.2% increase the absolute number of COPD and asthma-related dispensed medicines between 2004 and 2020, which represented a 27.2% increase between the two periods of time (p < 0.05).

The authors concluded that while the data showed a clear rise in hospital admissions for both conditions the reasons behind these increases were unclear and they called for further research to try and better understand the factors responsible for these higher rates.

Citation
Alwafi H et al. Trends in hospital admissions and prescribing due to chronic obstructive pulmonary disease and asthma in England and Wales between 1999 and 2020: an ecological study. BMC Pulm Med 2023