COVID-19 guidance in Sweden may have reduced people’s risk of heart attack, a study indicates

A new study suggests that COVID-19 guidance in Sweden may have reduced people’s risks of having a heart attack.

Using anonymous location data from cell phones, the researchers developed an aggregated picture of Swedish population activities and mapped it against attendances at the country’s 29 emergency cardiac angiography units.

Cardiac angiography is used to treat blockages in the blood vessels of the heart.

In those days when location data revealed that people were staying close to home, the percentage of patients going to hospital for emergency heart care dropped from an average of 63 patients per day in the pre-COVID years to a average of 55 patients per day during the first wave of the pandemic – March 1 to May 5, 2020. At its lowest point in early April, the decline in patients was 38%.

A downloadable graph shows the relative decline in patients attending cardiac angiography units. The decline has been seen since the beginning of March. Swedish public health authorities have advised people over the age of 70 to stay home since March 16. (See details in Notes to Editors).

In comparison, when location data showed that people were active at work or shopping or physically active, the proportional number of attendances at heart units increased.

Chris Gale, a professor of cardiovascular medicine at the University of Leeds, was one of the scientists involved in the study. He said: “This was a statistical analysis so cause and effect cannot be determined directly, but it identified a number of interesting associations.

“Although Sweden was not blocked, people aged 70 and over were urged to stay at home and this could have reduced exposure to some of the events known to trigger a heart attack such as stress, strenuous physical activity. , air pollution and exposure to some viruses. “

The study – The effects of movement trends on acute coronary syndrome during the COVID-19 pandemic – published in Journal of Internal Medicine, is one of the first scientific investigations to use aggregate mobility data from map services from mobile devices to help explain how COVID-19 and the health messages around the virus may have impacted people’s health.

The results in detail

A baseline measurement has been set for location activity data based on daily averages of pre-COVID times. The change from that baseline was measured as a percentage increase or decrease. The following associations were observed with data from angiography clinics:

• A 10% increase in retail and recreational activity has been associated with a 15% increase in heart attack and angina cases – collectively known as acute coronary syndrome (ACS) – seen at angiography clinics.
• A 10% increase in activity in grocery stores and pharmacies has been linked to a 14% increase in ACS cases.
• A 10% increase in workplace activity was associated with a 12% increase in ACS cases.
• A 10% increase in activity in the home category has been linked to a 38% drop in ACS cases.

The analysis using Apple data produced comparable results.

Researchers say the decline in people attending hospital with a heart attack has been observed in other countries, including the UK, where it is believed that people may not have sought emergency medical care for fear of contracting COVID. 19 or because they didn’t want to overwhelm. NHS services under pressure.

But the researchers say there is no evidence in Sweden that there were bed shortages, higher mortality from heart disease, or changes in the quality of care in hospitals – factors that could have suggested people got sick but decided not to seek help. of emergency.

They said in the paper: “Self-isolation, work from home and less rigorous recreational activities may have decreased stress and exercise-induced acute heart syndrome in individuals at risk and may perhaps explain the decline in the incidence of myocardial infarction. (heart attack) since the association between psychological stress and physical exertion and the incidence of myocardial infarction / ACS is well established “.

Researchers say messaging about hand hygiene and social distancing has reduced the spread of other respiratory conditions such as the flu which could also trigger heart problems.

The results provide a first glimpse of how data from mobile devices can provide a quick measure of how a population’s behavior could change and how this could affect the spread of the disease and possibly allow us to predict the level of future hospitalizations. “.

Dr Moman Mohammad, Stiudy Lead, Lund University

“We know that a stroke can be triggered by the same events that trigger a heart attack. During the first wave of the pandemic, there is evidence that the number of people who have suffered a stroke has also decreased.”