Women who have a cardiac arrest outside a hospital setting are less likely to be resuscitated by bystanders and more likely to die than men, suggests new research* published today in the European Heart Journal.
The researchers, led by cardiologist Dr Hanno Tan from the University of Amsterdam, The Netherlands, found that men and women did not receive equal treatment when experiencing a cardiac arrest in the community.
There are an estimated 30,000 out-of-hospital cardiac arrests in the UK each year and the survival rate is less than one in 10.
Dr Tan and his team analysed data from all resuscitation attempts made by emergency services between 2006 and 2012 in one province in The Netherlands.
They identified 5,717 out-of-hospital cardiac arrests treated during this period, 28% of which occurred in women.
Results showed that women were less likely than men to receive a resuscitation attempt by a bystander (68% versus 73%), even when there was someone there to witness the collapse (69% versus 74%).
Survival from the time of the cardiac arrest to admission to hospital was lower in women (34% versus 37%), and women were less likely to survive from admission to discharge (37% versus 55%).
Overall, the chances of women surviving to be discharged from hospital was about half that of men (12.5% versus 20%).
The researchers believe this is largely explained by the lower rate of shockable initial rhythm in women – 33% versus 52%.
They argued that a possible reason why fewer women have shockable initial rhythm by the time the emergency services reached them may be because fewer women than men tended to have a cardiac arrest when there were other people around to see it happen (there are more elderly women living on their own than men), and because the symptoms of a heart attack may not be recognised so quickly in women.
An important factor in the findings was that people did not recognise that women who collapsed were having a cardiac arrest, leading to delays in calling the emergency services and delays in providing resuscitation treatment.
The researchers also found differences in the way women were treated in hospital. They were less likely to be diagnosed with an acute myocardial infarction, and less likely to undergo coronary angiography or percutaneous coronary intervention.
Dr Tan said: “People may be less aware that cardiac arrest can occur as often in women as in men, and the women themselves may not recognise the urgency of their symptoms. Women may have symptoms of an impending heart attack that are less easy to interpret, such as fatigue, fainting, vomiting and neck or jaw pain, whereas men are more likely to report typical complaints such as chest pain.”
The researchers called for a range of measures to tackle the problem of survival differences between the sexes, ranging from public awareness campaigns about heart attack and cardiac arrest in women to reorganisation of health care systems in order to provide faster resuscitation to women, particularly those living on their own.
Sara Askew, head of survival at the British Heart Foundation, said: “This new insight is particularly worrying, given that we already know that women who have suffered a heart attack are less likely to receive the appropriate treatment. Now, it appears the case is the same for women who have cardiac arrests.”
*Blom M T, Oving I, Berdowski J, van Valkengoed I G M, Bardai A, and Tan H L. Women have lower chances than men to be resuscitated and survive out-of-hospital cardiac arrest. European Heart Journal. DOI: 10.1093/eurheartj/ehz297.