Campaigners are calling for more research and greater recognition of a heart problem that kills apparently healthy young adults.

Its been dubbed the adult version of “cot death” and it is so alarmingly prevalent that researchers recently claimed it to be the most common cause of unexpected death in adults under the age of 35.  Perhaps most worryingly of all, the first symptom is often death – in the form of a fatal heart attack.

Research published in the Lancet last year suggested that as many as eight lives were being lost each week in the UK to “Sudden Death Syndrome” (SDS), an umbrella term used for the many different causes of cardiac arrest in young people.  The conditions that lead to it include a thickening of the heart muscle and irregularities in the electrical impulses responsible for the natural rhythm of the heart.  Symptoms can include shortness of breath, light-headedness and chest pains – usually brought on by physical exertion – but equally, sufferers may be completely oblivious to their potentially impending doom.  The charity Cardiac Risk in the Young (CRY) recommends that anyone who has any of the symptoms mentioned or has had any young, sudden deaths in the family (researchers have discovered a positive genetic link), should be screened.

In fact, it feels so strongly about the benefits of screening that it carried out ECG testing in clinics across the country for people who are post-puberty but under 35.

Often, doctors just don’t make the link between heart problems and the younger members of the population, says CRY’s founder and chief executive, Alison Cox.

At the moment many cases of sudden death, where no cause has been identified are put down to “natural causes” in coroners’ reports.  Because of this new research funded by the British Heart Foundation suggests that the number of people over 16 who collapse and die suddenly without explanation could be much greater than is being recorded in official statistics.

The findings, published in the Quarterly Journal of Medicine last month, show that in just over four percent of sudden deaths among apparently “previously healthy” adults under the age of 65, no cause of death can be found, even following a full post-mortem examination.  Many of these deaths maybe due to electrical abnormalities in the heart, they believe but this is difficult to prove, as it’s a problem that’s only detectable when a person is alive.

The researchers say that because there’s no nationally recognised name or category for these unexplained deaths when they’re being officially certified the exact number of victims is unclear.

Says lead researcher, Dr Tim Bowker, associate medical director at the British Heart Foundation: “Our findings suggest that these deaths should be classed as the adult equivalent of sudden in fact death syndrome (SIDS).  If the condition is more frequent that we suspect – particularly if across the country pathologists and coroners are using different words to describe the cause of death – we need to give the condition a ‘name’ to help us gain a greater understanding of the scale of the problem.”

He points out that once cot death gained its official tag of SIDS it became possible to collate relevant dates and identify possible triggers.  As a result, the number of deaths fell by 70% in 10 years.

“Not until it is accepted practice to identify all these unexplained deaths and to label them, will it become possible to study them systematically, identify their causes and find ways of preventing them from occurring”, says Dr Bowker.  The name the researchers propose to is ‘sudden adult death syndrome’ or SADS.  “We want a term that is a SIDS adult equivalent.”

If coroners were to start using the term SADS, where in the past they might have recorded an open verdict or one of natural causes, “this will mean we can begin to collate accurate statistics and start to understand the true incidence of these conditions,” says Alison Cox.

As more is discovered about the problem, it could be that a formal screening system is introduced.  However, more research is needed first.  “It’s certainly not the case that everyone should be screened,” says Dr Bowker.  “But we need to look in more detail to find out what measures we can take to detect it and to lower people’s risk of dying.”

Alison Cox says it’s her ultimate wish to see all children receiving an ECG when they have their BCG vaccine, but she recognises that at the moment it’s just not viable for the NHS to get involved in this kind of mass testing.

Once a person is identified as being at-risk treatment is aimed at preventing complications and allowing the individual to get on with living a normal life.  There are a variety of drugs on offer, and one option is having an implantable cardioverter defibrillator (ICD) fitted, which delivers electrical impulses in the absence of normal impulses.

All in all, for most people, being told they have a heart problem shouldn’t significantly affect their lifestyle, although sufferers are often advised by their specialists to avoid strenuous activities such as competitive sports.