I have never really understood why some people are desperate for immortality. Like those crazy millionaires who have their heads frozen in liquid nitrogen. I am not afraid of dying, but I would like to die painlessly and without much fuss, and preferably with all my faculties intact*. But what am I likely to die of? We looked at figures recorded by the Ministry of Health of the primary causes of death for the 29,204 people who died in New Zealand in 2009. For simplicity, we have only looked at the causes that were responsible for more than 1% of those deaths and have summarised them in the infographic** below. It is important to bear in mind though, that the figures cover what was recorded on the death certificate which may not always be the immediate cause of death. For example, many of those who are recorded as having died of Alzheimer’s disease are more likely to have died of pneumonia or a urinary tract infection.

To see if people’s perceptions tallied up with reality, we took to social media and asked people what they thought were the biggest killers and what they were likely to die of***. So what did the Kiwis we surveyed think? Firstly, and unsurprisingly, that many would like to thought they would die of ‘old age’. Sadly this is not recognised as a cause of death by the Ministry of Health! It was also interesting how discomforting many people found the survey, with a number of people telling us that they did not want to think about how they might die, or skipping that question entirely. But many people did take the time to think about it, so how did their perceptions match the Ministry’s statistics?

31% of those surveyed thought they would die of conditions like angina, heart attacks, strokes and high blood pressure, which are classed as ‘circulatory diseases’. And they are probably right, because in 2009 circulatory diseases were New Zealand’s biggest killer, responsible for 35.5% of deaths (10,372 people).

71.8% of our survey participants underestimated the number of cancer deaths in New Zealand, although 22% of them thought that cancer would be the cause of their demise. In fact, cancer is the second largest killer, responsible for 29.1% of deaths (8,500 people) in 2009. Interestingly, 66% of those surveyed did not know that cancers of the digestive system are the most frequent cause of cancer deaths in New Zealand, though they recognised lung cancer is one of the biggest killers.

In 2009, traffic accidents and suicides were both responsible for more deaths in New Zealand than skin cancer (melanoma). Yet 48% of our survey participants perceived melanoma as the greater risk. Perhaps this shows how successful the ‘slip, slap, slop’ message has been.

Despite respiratory diseases being the third biggest killer of Kiwis, they were largely unrecognised by our survey participants with only 2.1% listing it as what they may die of.

It was very sad to see that 10 of the people we surveyed listed suicide as their cause of death, giving suicide a higher representation in our survey population than in real life. Could social media be a good forum for offering support to those struggling with thoughts of harming themselves.

Over the next few months we will be delving into the stats more closely, so if there is something you would like us to examine then please get in touch.

[Edited 18/01/2013 to correct a sentence]

*Then I would like to be buried in a shroud or biodegradable casket and return my vast store of nutrients back to the land. If space is an issue, then I quite like the idea of being cremated and popped into one of Spanish designer Martin Azua’s Bios Urns which are made from coconut shell, compacted peat and cellulose and contain the seed of a tree.

**Head on over to Mike’s Pictures of Numbers blog to see how the infographic came about and for a downloadable version.

*** We used Twitter, Facebook, SciBlogs and email to entice over 360 people to fill out our survey using the SurveyMonkey website. The full results are available on Shareshare. Like all online surveys, ours should not be considered representative of the population of New Zealand, but rather of people on social media who were happy to fill out our survey.

This post was inspired by the Guardian newspaper’s infographic ‘What we die of’ and is a collaboration between myself, chief number cruncher Dr Paul Gardner and data visualisation extraordinaire Dr Mike Dickison. Dr Paul Gardner (@ppgardne) is a Royal Society of NZ Rutherford Discovery Fellow and Senior Lecturer in Bioinformatics at the University of Canterbury’s School of Biological Sciences. He gets very excited about RNA. Dr Mike Dickison (@adzebill) is a freelance information designer with a PhD on the evolution of giant flightless birds. He quite likes ukuleles too. Dr Siouxsie Wiles (@SiouxsieW) is a Health Research Council of NZ Hercus Fellow at the University of Auckland’s Faculty of Medical & Health Sciences. She is rather keen on nasty bacteria and anything that glows in the dark.