The subject of my talk at this year’s conference was the impact of radiation toxicity on quality of life in older patients, which is a difficult subject to discuss because there are a lot of methodological considerations when you’re talking about quality of life generally and they tend to become a little bit worse when you talk about older patients where traditionally we don’t have a lot of trial data anyway. The types of information that we have is generally about fitter older patients rather than the broad spectrum of patients that you’re going to meet.
The types of things you need to take into account are things like missing data - there can be a higher percentage of missing data in older patients in relation to quality of life. Also, there is this phenomenon called the disability paradox, or a response shift over time, where older patients in general rate their quality of life quite high compared to younger patients even though they might have a high level of disability or they have maybe physical impairment or cognitive impairment. That’s something that skews the results as well. Traditionally the way that we have measured quality of life in older patients, we haven’t had elderly specific tools to measure that either, so that’s improving. The EORTC have developed an elderly specific module that would go along with their core quality of life instrument but fewer studies have used that to date. The studies that have used it have highlighted specific quality of life issues that we wouldn’t have known about otherwise.
I think that we need more research, we need more quality research and we just need to think about what’s important to older people. Certainly in oncology and in radiotherapy quality of life is even more important, especially for patients who might have limited life expectancy or they might have competing comorbidities that we need to take into account, so it’s important to do more research in the field.
How do you think radiotherapy can impact quality of life in older patients?
Two-thirds of our patients are older patients and about 50% of all cancer patients require radiotherapy at some stage of their treatment. Now, in some countries there is evidence of under-treatment, there is also evidence of over-treatment, so that’s where I think quality of life comes into play where you would use data from quality of life to have a discussion with patients about the impact of treatment on them and see what’s important to them. I think it’s part of a shared decision making approach; radiotherapy is a very important treatment, it’s not generally as toxic as chemotherapy but it has very specific toxicity depending on the site that you’re treating so quality of life is very important.
Do you think that this will also have a broader impact?
Twenty years ago, quality of life was only really spoken about in the context of research whereas now it’s increasingly being incorporated into clinical practice, again to inform shared decision-making and there is definitely more of a role for that in a clinical setting. I think that people like the EORTC have established a consortium earlier this year on setting international standards for reporting quality of life in trials and I think that those standards will be very welcome and they will need to be taken into account to provide more quality research in quality of life.
Could you discuss the poster you were presenting?
Last year one of our students at Trinity College conducted one of the first analyses of The Irish Longitudinal Study of Aging looking at survivorship issues in older cancer patients. She looked at wave 1 of the TILDA data and she looked specifically at health behaviours in terms of alcohol consumption, smoking and exercise. Her findings are interesting in that she didn’t see any improvement in health behaviours which is something that we obviously should be worried about. We obviously need to do more detailed research because of the small cohort of the entire TILDA dataset. Some of the things that we are looking at now in terms of survivorship care across the spectrum of cancer patients, not only older patients, is looking at the importance of health behaviours for long-term quality of life and also for disease prevention and I suppose that is important for older patients as well. That was a very interesting finding. The student’s name was Adele, Adele Ryan, and she did really good detailed analysis of the TILDA dataset, and was one of the first to look at cancer survivorship issues.
It’s something I suppose we need more research into why that is, maybe we’re not supporting patients through survivorship and I suspect that’s an issue also. We are not providing education on smoking cessation or providing support or providing education on the importance of physical exercise. There are other factors that come into play as well that perhaps there are psychosocial issues that are preventing patients from engaging more in physical exercise and doing those sorts of things. I think we need definitely to follow that up and to look at it in a more detailed way but it is certainly something that is worthy of further investigation.