Loyalty card data on over-the-counter medicine purchases could help spot ovarian cancer cases earlier, finds a new study involving UCL researchers.
The first-of-its kind study, published in JMIR Public Health and Surveillance, found that pain and indigestion medication purchases were higher in women who were subsequently diagnosed with ovarian cancer, compared to women who did not have ovarian cancer. This change in purchases could be seen eight months before diagnosis.
The study of almost 300 women also considered whether there is a link between diagnosis of ovarian cancer and a history of buying over-the-counter pain and indigestion medications, such as pain killers and digestive aids like antacids.
Symptoms of ovarian cancer can be unclear in the early stages of the disease, which leads to some people buying medication from a local pharmacy to alleviate their symptoms, instead of visiting a GP - as they do not think their condition is serious. These early symptoms can include loss of appetite, stomach pain and bloating.
Consequently, many people with ovarian cancer are diagnosed late, often when the cancer has already spread, and when their likelihood of survival has greatly reduced.
Dr Yasemin Hirst (UCL Behavioural Science & Health) led the preliminary study which paved the way for the latest research, where she is the lead behavioural scientist.
The work based at UCL investigated public acceptability, feasibility and building a better understanding of self-care behaviours before ovarian cancer diagnosis.
Dr Hirst said: "Self-care is about individuals' capability to manage illnesses, keeping healthy without the support from healthcare providers as well as the appropriate use of healthcare when it is required.
"Self-care is an important part of recognising and managing the early signs and symptoms of cancer which could resemble common illnesses and can be cared for without the guidance from healthcare providers. It is therefore crucial to understand to what extent this process may influence timely presentation in healthcare.
"The Cancer Loyalty Card Study (CLOCS) is one of the leading projects showing that our health behaviours can be measured beyond healthcare records using transactional data. This data is very exciting for behavioural scientists to further explore life-style changes, dietary behaviours and perhaps exploring other datasets (e.g. biosensors) that can provide more information about self-care and health outcomes."
Ovarian cancer is the sixth most common cancer in the UK, with around 7,400 people diagnosed each year and more than 4,000 deaths each year from the disease. One in 5 women with ovarian cancer are diagnosed in A&E and many do not receive any treatment for their disease, often because they are too unwell by the time they are diagnosed.
The study findings could help to identify people who may have ovarian cancer at an earlier stage, which is one of the most effective ways to improve survival. 93% of people diagnosed with ovarian cancer survive their disease for 5 years or more if diagnosed at the earliest stage (stage 1) compared to just 13% when diagnosed at the latest stage (stage 4).
Lead author, Dr James Flanagan (Imperial College London), said: "The cancer symptoms we are looking for are very common, but for some women, they could be the first signs of something more serious.
"Using shopping data, our study found a noticeable increase in purchases of pain and indigestion medications among women with ovarian cancer up to eight months before diagnosis, compared with women without ovarian cancer. This suggests that long before women have recognised their symptoms as alarming enough to go to the GP, they may be treating them at home.
"As we know earlier diagnosis of ovarian cancer is key to improving chances of survival, we hope this research can lead to ovarian cancer symptoms being picked up earlier and improve patients' options for treatment."
The study was carried out by researchers from UCL, Imperial College London and the University of Birmingham, and was funded by Cancer Research UK.
The research included loyalty card data from two UK-based high street retailers of 273 women. Of these participants, 153 were women who had been diagnosed with ovarian cancer, and 120 were women who had not. The researchers studied six years' worth of purchase histories from the women.
Participants were also asked to complete a short questionnaire about ovarian cancer risk factors, along with the symptoms they experienced (if any) and the number of visits to their GP in the year leading up to cancer referral or diagnosis for cases.
On average, participants with ovarian cancer began to recognise their symptoms about 4 and a half months before diagnosis. Of those who visited a GP to check their symptoms, the first visit occurred, on average, about 3 and a half months before diagnosis.
Women were able to participate in the study if they were over the age of 18, agreed that their loyalty card data could be used by the researchers and agreed to complete the short questionnaire.
The researchers note that more research is needed to confirm their findings and they hope that larger studies with patients diagnosed at different stages will be able to support and strengthen these results.
It is also hoped that this research could lead to the future development of an alert system for individuals to help the to seek medical attention for symptoms of cancer, or other diseases, sooner than they might otherwise do.
The research team has been funded by Cancer Research UK to continue this work by investigating whether purchases of over-the-counter products could be used in a similar way for other cancers, such as stomach, liver, and bladder cancers - all of which also commonly have non-specific symptoms.
Patient story
Fiona Murphy is an ovarian cancer patient representative who helped develop the study. She was diagnosed with mucinous ovarian cancer in 2008 after being symptomatic for nearly two years.
Fiona said: "I lived on Gaviscon for 18 months prior to my ovarian cancer diagnosis, it went everywhere with me due to severe acid reflux. Had this been associated with ovarian cancer, I would have had a faster diagnosis, far less surgeries and better fertility options.
"I wanted to help with developing this study because I had the wrong diagnosis for nearly two years. If there is a way to get an earlier diagnosis, I want to help people who are in the same position I was in."
Fiona was not one of the 273 participants whose loyalty card data was used for the study.
