Rates of Depression in Cancer Patients
Being diagnosed with cancer has a huge impact on people's lives, so it's no surprise that sufferers are more likely than the general population to develop major clinical depression. Until now, however, we haven't known just how likely it is, and whether the type of cancer has an effect. In a series of 3 papers published this week in the Lancet, Michael Sharpe from Oxford University investigated spoke to Ginny Smith about this issue, to see whether interventions could improve depressive symptoms.
Michael - Well first of all, we have to be clear what we mean by depression and that word is used very imprecisely. If we're talking about sadness or general distress, this causes a very high rate. But here, we're focusing on - as you say - clinical depression. Depression that is debilitating, that a psychiatrist would say needs treatment. If we focus on that, we find that it varies with the type of cancer. So, some cancers like lung cancer, it's about 13% of patients and it goes down slightly in rate through breast, colorectal, and in the genitourinary cancers like prostate cancer, it's about 5%. But if we are talking about a population point prevalence of about 2%, as you can see, all those cancer types have elevated rates of major depression.
Ginny - And do we all know what's different about the different kinds of cancer that might mean you're more likely to get depression if you've got one type?
Michael - That's a very good question. I mean, the obvious one is that lung cancer, as people may know is, one of the cancers that we haven't made much progress in cancer treatments. So, the life expectancy for lung cancer is poor. Only about 13% of patients live more than 5 years. So clearly, if in so far as the depression is determined by the awfulness of your cancer, it's perhaps not surprising that lung cancer has a higher rate. Of course, there may be other biological mechanisms as well that we don't well understand.
Ginny - And yet, not everyone with lung cancer will develop depression. So, do we know what other factors make it more likely that you will go on to have depression?
Michael - Yes. In our analysis here, we found that depression was more likely in younger patients, in female patients, and in people living in areas which regardless having higher social deprivation, we didn't measure it in this study, but other studies have found - perhaps not surprisingly - a previous history of depression, a marker of vulnerability if you like, also makes you more likely to become depressed.
Ginny - Now, some of those things are markers to depression on their own, living in poorer areas and that sort of thing, we know makes you more likely to get depression. Is there a kind of interaction going on there?
Michael - Yes, I think that's right. It would be surprising if the risk factors for depression with cancer were completely different from those for the risk factors for depression in general. And of course, as you say, many of those are similar. But clearly, with cancer, we've moved the prevalence rates up 2 or 3 times from the general population. So, the whole thing about having cancer is adding something to those risk factors.
Ginny - Now, you were also looking at treatments and how you might be able to help these people. What kind of treatments are currently on offer alongside the kind of traditional cancer treatments to help people mentally?
Michael - Well, the standard treatments that of course any of us would get for depression would include seeing your GP who might prescribe an anti-depressant drug, seeing a counsellor or a psychologist who might give you some psychological treatment and people with cancer have those kind of treatments available to them. But what we found is that despite that availability, 75% of patients with major depression in our study were not receiving what we deemed an adequate treatment.
Ginny - That's shocking. What can we do to lower that percentage?
Michael - I think it's a complex situation and there are many reasons why effective treatment doesn't happen. So, what we've done is built an intervention, a package if you like, which tries to address the main problems that prevent people getting treatment. So, there's first of all, identifying who's depressed, there's educating the patient what depression is, there's making sure they get treatment and we've offered patients both anti-depressants and psychological treatment. I think most importantly, we've integrated the treatment of depression with our cancer care, so they don't have to become a mental health patient. They don't have to go to a different service or a different trust. It's part of their cancer treatment.
Ginny - So, I imagine that makes it logistically easier for the patient, but also somehow, alleviates some of the perhaps stigma around getting treated for depression.
Michael - I think that both those things are absolutely right. I think it's very important to be aware we have to - this treatment, the most face to face contact was given by cancer nurses and they had to spend quite a lot of time with the patients, helping them understand what depression was and that depression could be treated and how it could be treated. And so that, if you just tell people they are depressed and ask them to go often do things, most of them don't.
Ginny - And how effective was your new integrated method of treatment?
Michael - So, just following on this conversation then, so we've said that all these things were available to people and what we found - perhaps the most surprising finding - is if you tell the patient they've got depression, and you tell their doctors they've got depression and you encourage everybody to do something about it, the outcome is really very poor. So, 6 months after that, only 17% of patients having usual care have a major improvement in their depression. With our integrated package, which there's no wonder treatments in here, it's taking all the treatments we know about, but packaging them effectively, that goes right up to 62%.
Ginny - That's a big jump, but does it work just as well for all the types of cancer you looked at?
Michael - Yes. If you look at a subgroup analysis, none of the factors such as gender, age, or cancer type have any major effect on the treatment size, that's right.
Ginny - How long do you think this will be before it's rolled out to all cancer patients?
Michael - Well, implementation is always a challenge in medical research. We have the phenomena, it's referred to in the states of bench to bookshelf, and a lot of findings just stay in a journal. I am hopeful that the findings here, the treatment size is so large, the cost of the treatment is relatively modest in a cancer context, about 600 pounds, that we will start to see implementation, and we are in discussion with some cancer centres, both in the UK and in United States.