99 per cent of coronavirus deaths in Italy are patients with existing medical problems, a study by the country’s health service has found.
Research into 355 deaths found that only three of the victims, 0.8 per cent, had been clear of illnesses before they were infected.
Nearly half of them – 48.5 per cent – already had three or even more health conditions before they were diagnosed with Covid-19.
Another 25.6 per cent had two other ‘pathologies’, while 25.1 per cent had one.
The research by Italy’s National Institute of Health is consistent with previous findings that people with existing illnesses are more likely to die from coronavirus.
According to the study, the most common of these problems in Italy include high blood pressure, heart disease and diabetes.
Some 76.1 per cent of the patients who died of Covid-19 had previously had problems with high arterial blood pressure, the study found.
More than a third – 35.5 per cent – had diabetes, while 33.0 per cent had suffered from ischemic heart disease.
Nearly a quarter, 24.5 per cent, had suffered from atrial fibrillation. Less common examples included dementia and liver disease.
Scientists have not yet established why people with high blood pressure are more vulnerable to the coronavirus.
The Centers for Disease Control and Prevention in the U.S. says it needs ‘more data to become available’ to investigate the link properly.
The illness is common and often life-long – around 16million people in the UK and 78million in the US have the condition and many take medication to control it.
It is not clear whether high blood pressure directly raises the risk of fatal COVID-19, or whether it simply pops up so often because it’s so common among the elderly, who are already the most likely to die on account of their age.
For example, between 72 and 80 per cent of over-75s in the US have the condition.
According to a study in the journal Immunology Research, high blood pressure causes low-level damage to the insides of blood vessels and the damage stimulates a small response from the immune system meaning that, when it has to respond to a real threat like a viral infection, there is a greater risk of it overreacting.
Immune overreaction can lead to sepsis or organ failure, which are often fatal, and are known to be a cause of death among coronavirus patients.
The Italian study also found that the average age of people who died from the virus in Italy was 79.5, although it was slightly higher for women than men.
That is also consistent with previous findings from around the world that older people are more vulnerable to the disease.
Italy’s population is the second-oldest in the world, after Japan’s, and the country has suffered the worst outbreak in Europe by far.
There have been 35,713 confirmed virus cases in Italy, with 2,978 deaths.
The study found that 77 per cent of the patients who eventually died were suffering a fever when they were taken to hospital.