‘The link between air quality and blood pressure and asthma has been extensively documented’ 

• IT has been suggested that the recent fall of 23 per cent in emergency admissions to A&E is for psychological reasons; people are too anxious or depressed or concerned about being a burden on the NHS (Covid blues) to come to A&E because of Covid-19.

Concerns are that such behavioural avoidance may result in people with cardio­vascular disease and asthma not receiving treatment promptly.

To our surprise, with lockdown, we independently observed significant falls in our own blood pressure and an improvement in asthma and considered the possible reasons for this.

The link between air quality and blood pressure and asthma has been extensively documented. With lockdown, the air quality in major cities across the world, including central London, has significantly improved with blue skies observed.

Thus although Covid blues may part of the reason for non-attendance at A&E, improvements in air quality known to be associated with lower blood pressure and improved lung function, and thus reduced morbidity and mortality may offer another explanation.

Similar falls in morbidity and mortality were seen after a smoking ban in public places.

We acknowledge this hypothesis remains to be tested.

Once more data are available, analyses of A&E attendance before and after the Covid-19 outbreak could be conducted against other potential predictors of attendance, including presenting condition (incorporating, cardiovascular disease and asthma in the model), air quality and location (for example, Atlantic seaside towns and big UK cities).

If A&E attendance and reduced health care costs are associated with improvements in blue skies rather than Covid blues, considerable weight would be added to the argument for the need to improve air quality, especially in major conurbations.

DR MARC A SERFATY
Associate Professor in Psychiatry UCL

DR MIKE BEARY
Consultant Psychiatrist (Retired)