1 00:00:00,180 --> 00:00:07,509 I told her. But today I thank you and thank you, Emily and Margaret, for the invitation. 2 00:00:07,510 --> 00:00:12,730 Can everybody hear me? Great. So, yeah, really glad to be here. 3 00:00:13,450 --> 00:00:20,500 Really interesting how big data has taken off since I started do my stay over ten years ago now. 4 00:00:20,530 --> 00:00:29,920 So I'd like to spend the next 45 minutes just talking to you about what I've learned over that time about heart failure in primary care, 5 00:00:30,070 --> 00:00:34,570 in the context of those big data studies that we've done as part of our group. 6 00:00:34,600 --> 00:00:40,389 So as Emily said, I'm a GP, so I'm a GP in the Midlands. 7 00:00:40,390 --> 00:00:45,310 In a suburban practice we look after about 10,000 patients in our parts. 8 00:00:46,330 --> 00:00:49,569 But I'm also a researcher as well at the University of Oxford. 9 00:00:49,570 --> 00:00:53,320 So just around the corner in the Nuffield Department of Primary Care Health Sciences, 10 00:00:53,920 --> 00:01:01,840 I'm also a member of the nice Chronic Heart Failure Guideline Committee and the Quality Standards Committee. 11 00:01:01,840 --> 00:01:07,719 So that guideline was updated in 2018 and the quality standard is being updated at the moment. 12 00:01:07,720 --> 00:01:13,330 So that gives me a slight angle on policy as well as my research and clinical work. 13 00:01:13,540 --> 00:01:21,160 And hopefully I'll bring that all together in the talk to show how big data can be very powerful for us to improve patient care. 14 00:01:25,040 --> 00:01:30,440 So my research focuses on big data as well as other methodologies. 15 00:01:30,890 --> 00:01:34,610 As Emily mentioned, I think it's important to put that into context. 16 00:01:35,450 --> 00:01:45,920 So big data, what do we mean by that? Well, when I'm in surgery as a GP, I'll be inputting clinical codes about my patient, about diagnosis. 17 00:01:46,490 --> 00:01:51,140 I'll put treatments are prescribed treatments through the electronic medical record. 18 00:01:51,470 --> 00:01:55,220 If a patient has a test that will appear in their electronic medical record. 19 00:01:55,460 --> 00:01:59,120 So there's lots of data that we input as part of routine clinical care. 20 00:01:59,660 --> 00:02:06,800 And as researchers, we're very fortunate to be able to access this data in large primary care datasets. 21 00:02:07,160 --> 00:02:14,149 So things like the clinical practice research, datalink key research or Kids, the Health Improvement Network, 22 00:02:14,150 --> 00:02:19,850 these are all examples of large primary care datasets that we can use for research purposes. 23 00:02:20,330 --> 00:02:27,210 Our research group has predominantly over the years, and the three examples I give today are all from CPR. 24 00:02:30,810 --> 00:02:33,980 But as a GP I see patients, I see real people. 25 00:02:33,990 --> 00:02:38,280 So the research databases are anonymized. We don't know who these people are. 26 00:02:38,280 --> 00:02:41,100 It's at a population level. We see the numbers. 27 00:02:41,430 --> 00:02:50,280 But when I'm in practice, in a clinic in in the town where I live, I see patients, all types of patients. 28 00:02:50,280 --> 00:02:57,479 So we serve people from young babies through to very elderly and people reaching the end of their lives. 29 00:02:57,480 --> 00:03:01,320 So we provide holistic care to the community which we serve. 30 00:03:01,830 --> 00:03:05,219 And as part of that, we see patients with heart failure, 31 00:03:05,220 --> 00:03:09,540 people with newly diagnosed heart failure, people that don't know they've got heart failure yet, 32 00:03:09,780 --> 00:03:14,730 people that have been living with heart failure for years and people that are dying of heart failure. 33 00:03:15,240 --> 00:03:25,620 So that gives me a real insight into what it's like being diagnosed and living with the condition, and that really helps to inform my research. 34 00:03:28,630 --> 00:03:33,340 So let's talk a bit about heart failure. So just the basics. 35 00:03:33,340 --> 00:03:40,750 Heart failure occurs when the heart is struggling to pump enough blood around the body to meet the metabolic needs of the organs. 36 00:03:41,290 --> 00:03:49,119 And that manifests for the patients in fluid building up in the lungs, causing them to feel really breathless and often increasingly breathless. 37 00:03:49,120 --> 00:03:58,480 Over time, they can also get really swollen legs and they can get fatigue, almost exhaustion, because their organs aren't being perfused properly. 38 00:03:58,960 --> 00:04:05,170 And there the symptoms that patients get, they can have one of those symptoms, they can have all of those symptoms. 39 00:04:05,380 --> 00:04:12,010 But there's around a million people in the UK living with heart failure at the moment and there'll be around 200,000 40 00:04:12,010 --> 00:04:21,190 people diagnosed each year with a new diagnosis of the condition it accounts for a large proportion of NHS expenditure. 41 00:04:21,190 --> 00:04:27,639 So 3 to 4% of the total budget goes on heart failure and that's largely due to hospital costs. 42 00:04:27,640 --> 00:04:33,760 So A&E attendances heart failure cuts around 5% of emergency hospital admissions. 43 00:04:34,120 --> 00:04:41,920 Patients tend to have a longer stay if they've got heart failure compared to other conditions, and they're frequently readmitted to hospital. 44 00:04:43,180 --> 00:04:49,329 And we find that many patients get their first diagnosis of heart failure on an emergency admission. 45 00:04:49,330 --> 00:04:53,050 So they may have had a gradual onset of symptoms up to that point. 46 00:04:53,410 --> 00:04:59,110 But many patients actually get admitted through a prior to their first diagnosis. 47 00:04:59,110 --> 00:05:03,790 And that's something I'm particularly interested in and I'll talk more about in the in the lecture. 48 00:05:04,540 --> 00:05:06,960 And these patients do have a poor prognosis. 49 00:05:06,970 --> 00:05:14,410 So the outlook for people with heart failure is similar to the outlook for people with with common types of cancer. 50 00:05:14,920 --> 00:05:20,340 But it's not all doom and gloom. It's a very treatable and increasingly treatable condition. 51 00:05:20,740 --> 00:05:25,959 We have a large number of drugs which we know can improve quality of life for patients, 52 00:05:25,960 --> 00:05:31,780 control their symptoms, prevent them from going into hospital and improve their survival. 53 00:05:32,260 --> 00:05:37,239 And this new drugs just come on the market, which are really improving outlook for these patients. 54 00:05:37,240 --> 00:05:44,709 So getting a diagnosis of heart failure is absolutely key to accessing these evidence based treatments, 55 00:05:44,710 --> 00:05:48,160 which we know can improve both quantity and quality of life. 56 00:05:51,450 --> 00:05:55,120 So that's the burden of heart failure for the population in the health care system. 57 00:05:55,140 --> 00:05:57,330 What about the patient and their family? Well, 58 00:05:57,360 --> 00:06:06,750 I did some qualitative work a couple of years ago interviewing people with a new diagnosis and ask them just to describe their diagnostic journey. 59 00:06:07,320 --> 00:06:11,520 And they found the term heart failure incredibly frightening. It sounds frightening, doesn't it? 60 00:06:11,550 --> 00:06:18,450 Heart failure. A lot of people felt it was a sort of imminent demise and this one patient just really hadn't 61 00:06:18,450 --> 00:06:23,410 realised what his symptoms meant or recognised that there was something seriously wrong. 62 00:06:23,430 --> 00:06:26,490 He said, I just thought it was probably my age. 63 00:06:26,820 --> 00:06:33,270 I don't think I thought it was the heart to start with. No, I just thought it was because I was walking a long distance and needed to stop. 64 00:06:33,690 --> 00:06:37,239 So we often find this in the qualitative research we've done. 65 00:06:37,240 --> 00:06:41,370 These patients normalise their symptoms and don't necessarily recognise heart 66 00:06:41,370 --> 00:06:45,720 failure in a way they might recognise other conditions where awareness is better. 67 00:06:47,780 --> 00:06:51,679 So during the talk I'd like to give three examples from our work. 68 00:06:51,680 --> 00:06:55,510 So I should say I work with a fantastic group in the department. 69 00:06:55,520 --> 00:06:59,540 So I co-lead the heart failure research team with Professor Richard Hobbs, 70 00:06:59,870 --> 00:07:05,240 and we've worked together for 15 years looking at the primary care aspects of heart failure in different ways. 71 00:07:05,660 --> 00:07:13,520 And I'd just like to give three examples where we use big data to answer important clinical questions and show how it can translate 72 00:07:13,520 --> 00:07:19,310 from these millions of numbers that you're seeing your spreadsheet to actually answering important questions for patients. 73 00:07:20,480 --> 00:07:27,050 And the first one I'd like to start with this survival. So survival is tricky. 74 00:07:27,320 --> 00:07:34,760 When somebody is diagnosed with a condition, it can be challenging to know what they want to know, what they don't want to know. 75 00:07:35,270 --> 00:07:39,170 But it's important that we have answers to questions patients might ask us. 76 00:07:39,980 --> 00:07:45,350 And as a heart failure group, we have a fantastic peer group, so patient and public involvement. 77 00:07:47,300 --> 00:07:51,290 They're a group of people that have got experience of heart failure and they give us 78 00:07:51,290 --> 00:07:55,340 honest answers when we ask them about the types of research we're thinking about doing. 79 00:07:55,460 --> 00:08:01,640 And then we're involved in throughout the research process through to dissemination of our findings at the end. 80 00:08:01,820 --> 00:08:08,420 And it's really fascinating, actually, our patients felt that they did want to have discussions around survival. 81 00:08:08,600 --> 00:08:13,180 They felt the discussions they had had in their own experience were often inadequate. 82 00:08:14,150 --> 00:08:18,800 One said, I like doctors to have the facts, and I felt that they just hadn't. 83 00:08:19,250 --> 00:08:27,290 And also this idea of this frightening term and imminent demise needed to be addressed by the clinician rather than ignored. 84 00:08:27,950 --> 00:08:31,790 So we decided to do a study called Survive H.S. 85 00:08:34,170 --> 00:08:36,879 To answer these specific type of questions. 86 00:08:36,880 --> 00:08:43,350 So a patient might ask me as a GP if I tell them they've got heart failure or the specialist has told them and they come back to me, 87 00:08:43,350 --> 00:08:47,910 So what is that and what does that mean? So how long will I survive? 88 00:08:48,570 --> 00:08:53,160 What will I die from? Or is outlook for people like me improving? 89 00:08:53,190 --> 00:08:57,840 Now, not every patient will want to know the answers to these questions, but some people might. 90 00:08:58,110 --> 00:09:03,120 And as a GP sitting in front of that patient, I want to know the answers. 91 00:09:03,120 --> 00:09:05,609 And you might think, Well, don't we know this already? 92 00:09:05,610 --> 00:09:12,839 There's a lot of work in cancer epidemiology where these these answers are very well known, but not in heart failure so much. 93 00:09:12,840 --> 00:09:23,639 So a lot of the data on survival comes from large screening studies, often from the US, which is a different population to the UK or from hospitals, 94 00:09:23,640 --> 00:09:29,190 patients and people in hospital with heart failure are quite different to people living in the community with heart failure. 95 00:09:30,120 --> 00:09:37,470 So we felt we were in a good place to answer this question using big data and this was the end result. 96 00:09:37,740 --> 00:09:45,720 So this was a paper published in the BMJ on Valentine's Day in 2019, which seemed very appropriate and timely. 97 00:09:45,750 --> 00:09:47,190 I think it was just coincidence, 98 00:09:47,190 --> 00:09:55,560 but we looked at trends in survival after a diagnosis of heart failure in the United Kingdom and over a long time period. 99 00:09:55,920 --> 00:10:02,550 So from the millennium, up until the most recent data when we started the study in 2017. 100 00:10:06,060 --> 00:10:15,000 So this was a population based cohort study using the clinical practice research datalink which you'll, you'll have heard of already on the module. 101 00:10:15,450 --> 00:10:20,489 So a large anonymized primary care dataset and we used a long time period. 102 00:10:20,490 --> 00:10:28,820 So we went from the 1st of January 2000 up until the end of December 2017, and we were doing the data in 2018. 103 00:10:28,830 --> 00:10:31,830 So we went all the way to the end of the previous year. 104 00:10:32,100 --> 00:10:40,260 The data completeness. One of the values of big data is that we can link to other datasets. 105 00:10:40,710 --> 00:10:43,470 So we linked to hospital episode statistics. 106 00:10:43,470 --> 00:10:51,270 So that gives us an idea of what happens to these patients in hospital when they go in, what they go in for, how long they're there. 107 00:10:52,230 --> 00:10:59,340 And we also had linkages to the Office for National Statistics Mortality Registry. 108 00:10:59,340 --> 00:11:04,590 So that tells us when patients have died and also what they've died of. 109 00:11:04,590 --> 00:11:10,380 And that information comes from the death certificate completed by the doctor who is last involved with their care. 110 00:11:10,920 --> 00:11:17,850 So these are quite powerful combinations because we can really get an insight into what's happening with these patients. 111 00:11:21,900 --> 00:11:30,840 So in survive. Tess We had 395 practices records for over 2 million people, 112 00:11:31,080 --> 00:11:39,690 so no cohort study or screening study where you actively recruit patients who would achieve anywhere like this number of people. 113 00:11:39,870 --> 00:11:48,599 You just wouldn't have the funding to do it. We chose people over the age of 45 because they're people that are likely to 114 00:11:48,600 --> 00:11:51,629 develop heart failure and those who get heart failure when they're younger, 115 00:11:51,630 --> 00:11:59,160 it tends to be a congenital cause. And that's a different condition with with different treatment options. 116 00:12:00,240 --> 00:12:08,840 So within this 2.4 million people, we found maybe 56,000 people with a new diagnosis of heart failure. 117 00:12:08,850 --> 00:12:13,710 So that's the new diagnostic code within their primary care records. 118 00:12:14,670 --> 00:12:23,630 Average age of diagnosis was 77, which is similar to what you find in other epidemiologic studies in heart failure. 119 00:12:24,510 --> 00:12:28,709 And we looked with the linkage with hospital less episodes statistics what 120 00:12:28,710 --> 00:12:34,500 proportion of people had been admitted to hospital around the time of diagnosis? 121 00:12:34,500 --> 00:12:41,190 And we found it was around 43% in our cohort, although some studies have reported that to be even higher. 122 00:12:43,950 --> 00:12:49,709 So we did survival analysis looking at age, sex and practice, match controls. 123 00:12:49,710 --> 00:12:53,790 So we had the people with heart failure diagnostic code and then we matched them by age, 124 00:12:53,790 --> 00:13:01,140 sex and practice to people that just didn't have a code that just to see the difference in survival and they saw a kaplan-meier curve. 125 00:13:02,100 --> 00:13:09,720 So the blue line is those without heart failure in their records and the dotted yellow line is those with heart failure. 126 00:13:09,960 --> 00:13:16,650 And as you can see, there's a dramatic difference. So X-axis, this time y axis is survival probability, 127 00:13:16,920 --> 00:13:23,430 and there's a real reduction in survival in those with heart failure compared to their peers who don't have heart failure. 128 00:13:24,570 --> 00:13:31,110 And just looking at that risk table, I think that's also the power of big data is just the sheer numbers. 129 00:13:31,120 --> 00:13:40,890 So each time point to five years, at ten years, even at 15 years, we've got lots of people in the cohort to look at and compare. 130 00:13:40,900 --> 00:13:47,550 So we can really see what's happening within that population and what the the trend looks like. 131 00:13:49,530 --> 00:13:58,679 And we also dig a little bit deeper. So if we want to answer the question, what is is the survival rate for people at one year, five, ten years? 132 00:13:58,680 --> 00:14:05,370 We can calculate that from the survival analysis, but we can also look at it by gender, but also by age. 133 00:14:06,480 --> 00:14:14,820 And as you can see at a younger age, your chance of surviving a year at a 90% if you're between 45 and 54. 134 00:14:15,750 --> 00:14:23,220 But as you go down in the older age groups, when you get to 75 to 84, it's it's 76.5%. 135 00:14:24,090 --> 00:14:32,760 So if you're talking to the patient in front of you, it's helpful not only to have an overall idea of survival rates in the general population, 136 00:14:33,120 --> 00:14:36,749 but it's also important to put it into context of the patient. 137 00:14:36,750 --> 00:14:45,600 Demographics and particularly age is very influential on survival, as you would expect, and I think that's important for us to report in our papers. 138 00:14:45,600 --> 00:14:52,800 When the BMJ paper came out, there was a lot of fear, I think, because overall the survival did look pretty bad. 139 00:14:53,070 --> 00:14:55,170 But actually if you look at younger patients, 140 00:14:55,170 --> 00:15:03,000 the survival wasn't as bad as the overall cohort because there are plenty of treatments available to improve prognosis. 141 00:15:05,520 --> 00:15:12,780 So we also looked at cause of death and we had over 30,000 deaths within the cohort. 142 00:15:12,780 --> 00:15:15,990 So a large proportion of the cohort died during the follow up. 143 00:15:16,980 --> 00:15:20,010 And this allowed us to look at what the causes were. 144 00:15:20,010 --> 00:15:23,999 So patients with a diagnosis of heart failure, what do they actually die from? 145 00:15:24,000 --> 00:15:27,570 Do they die from heart failure or do they die of something else? 146 00:15:28,050 --> 00:15:32,070 And as you can see on the so on a death certificate, you will put the primary cause of death. 147 00:15:32,080 --> 00:15:37,709 So the main thing that has led to death in that person and then you would put secondary 148 00:15:37,710 --> 00:15:42,240 causes which are sort of contributing factors but not the main thing they died from. 149 00:15:42,240 --> 00:15:51,690 So heart failure was the main cause in 7.2%, but it was actually influential in around half of patients. 150 00:15:52,410 --> 00:15:58,830 So that's important to know. But also that means 50% of people with heart failure actually died of something else. 151 00:15:59,430 --> 00:16:06,749 And that's important as a GP to bear in mind because these patients are usually living with 152 00:16:06,750 --> 00:16:11,010 several other long term conditions and we don't want to just focus on the heart failure, 153 00:16:11,010 --> 00:16:16,890 we want to focus on managing all of those conditions to give them the best quality of life and the best survival chances. 154 00:16:17,640 --> 00:16:20,049 So we also looked at the top three causes. 155 00:16:20,050 --> 00:16:27,390 So severe cardiovascular disease as high as you would expect, but then the next one down, respiratory and also cancer. 156 00:16:28,230 --> 00:16:31,470 So useful information for us to to have. 157 00:16:35,810 --> 00:16:39,930 And we also looked at trends over time. So what we want to see is improvement. 158 00:16:39,960 --> 00:16:44,060 So medical science improving survival rates for people with conditions. 159 00:16:44,210 --> 00:16:51,740 And we've seen this in cancer say cancer research. UK say that survival rates have doubled in cancer overall over the past 40 years. 160 00:16:52,070 --> 00:16:57,080 Now, unfortunately, we just don't see the same improvement in heart failure. 161 00:16:57,470 --> 00:17:04,940 So as you can see on the x axis, this the the year of diagnosis and then the Y axis is survival percentage. 162 00:17:05,270 --> 00:17:13,070 And there's a very slight increase in one year, five year and ten year survival rates over that time period. 163 00:17:13,910 --> 00:17:20,430 But if we look at the the differences from the start of the study to the end, it's really quite small numbers. 164 00:17:20,450 --> 00:17:26,210 So between six and 7% improvements in the one, five and ten year survival rates. 165 00:17:27,470 --> 00:17:33,560 Whereas as I said, with cancer, there's been a doubling. So 200% improvement in a 40 year period. 166 00:17:33,590 --> 00:17:39,920 So we still have a lot of work to do to improve patient's chances once they're diagnosed. 167 00:17:42,180 --> 00:17:46,229 And with the linkage we were also able to look at hospitalisations. 168 00:17:46,230 --> 00:17:54,510 So patients hospitalised around the time of diagnosis compared to those who didn't end up going into hospital around the time of diagnosis. 169 00:17:54,930 --> 00:18:01,710 And you can see the yellow line are those that weren't admitted and the pink cast on those were admitted. 170 00:18:01,980 --> 00:18:08,280 So patients admitted to hospital around the time of diagnosis had a worse survival than those who weren't. 171 00:18:08,610 --> 00:18:14,309 Now that that seems to make sense, but that might be important for us in primary care, 172 00:18:14,310 --> 00:18:20,340 because if we can actually keep people out of hospital by diagnosing and treating them a bit earlier, 173 00:18:20,640 --> 00:18:24,480 that we might actually improve the survival chances potentially. 174 00:18:24,540 --> 00:18:27,540 So there's a definite different scene with the data. 175 00:18:30,380 --> 00:18:37,430 And we also looked at both hospitalised and non-hospitalized patients in terms of the improvements on the left. 176 00:18:37,430 --> 00:18:42,799 It's those that were in the community, not in hospital and their survival rates. 177 00:18:42,800 --> 00:18:47,390 There has been an improvement compared to those who were hospitalised. 178 00:18:47,390 --> 00:18:53,240 So we really haven't seen much improvement at all in people that get hospitalised around that time of diagnosis, 179 00:18:53,240 --> 00:19:00,170 whereas people in the community there has been more improvement than looking at the the cohort as a whole. 180 00:19:04,210 --> 00:19:08,350 So there's strengths and limitations with big datasets. 181 00:19:08,680 --> 00:19:14,680 You get a large number of people and that is a very powerful thing for research. 182 00:19:14,680 --> 00:19:21,730 So we can look at trends over time. We can compare survival in those that do or don't have the condition. 183 00:19:21,940 --> 00:19:27,130 We can calculate survival rates based on age, based on gender. 184 00:19:28,990 --> 00:19:34,660 The downside of datasets, as I'm sure you've covered already, is that, as I said at the beginning, 185 00:19:34,660 --> 00:19:39,820 we use the primary care record predominantly to record our clinical care. 186 00:19:40,120 --> 00:19:45,729 So when I'm sitting in my surgery, seeing patients every 10 minutes at the forefront of my mind, 187 00:19:45,730 --> 00:19:50,530 isn't that this clinical code might be used by a researcher in Oxford at some point in the future. 188 00:19:50,530 --> 00:19:57,340 So I need to get it right. I mean, it does it does make me very aware of the need to code properly. 189 00:19:57,880 --> 00:20:02,200 But this is a snapshot of what's happening in real life clinical practice. 190 00:20:02,500 --> 00:20:07,120 Now, CPR data very good at looking at the quality of coding within their practices. 191 00:20:07,330 --> 00:20:11,040 So they do make sure that the practices are up to standard. 192 00:20:11,050 --> 00:20:21,580 So what we're seeing is reflective of real life primary care, but it is predominantly for routine clinical care. 193 00:20:21,580 --> 00:20:28,299 I think that is a strength as well because it does show real life recruiting patients into research studies. 194 00:20:28,300 --> 00:20:33,400 Does involved involve a certain type of bias, you know, who is willing to participate, 195 00:20:33,400 --> 00:20:37,930 etc., whereas this is showing what is happening every day in the community. 196 00:20:37,930 --> 00:20:40,210 A million patients a day see their GP. 197 00:20:42,220 --> 00:20:51,310 Clinical coding is something that we acknowledge is a limitation in the discussion of all our papers, particularly in heart failure. 198 00:20:51,310 --> 00:20:53,980 It's relevant for the type of heart failure. 199 00:20:53,980 --> 00:21:01,540 So two types of heart failure, heart failure with reduced ejection fraction and heart failure with preserved ejection fraction, 200 00:21:01,660 --> 00:21:08,080 and the treatments for those are quite different. So it's important at diagnosis to differentiate between the two, 201 00:21:08,410 --> 00:21:16,180 but that may not necessarily be recorded in the primary care record and we see in these codes increasingly use more recently. 202 00:21:16,420 --> 00:21:19,299 But if we go back a few years, they weren't really being used before. 203 00:21:19,300 --> 00:21:24,070 So we can't see what type of heart failure it is that we're looking at, unfortunately. 204 00:21:24,070 --> 00:21:26,980 But in the future we are likely to be able to see that. 205 00:21:28,210 --> 00:21:35,950 The other thing which review is sometimes say to us is around the reliability of death reporting in the UK because we don't do many post-mortems, 206 00:21:35,950 --> 00:21:42,040 it relies on the doctor looking after the patient during their last illness and what they put on the death certificate. 207 00:21:43,690 --> 00:21:48,340 But as a reporting system, it is one of the most robust in the world. 208 00:21:49,000 --> 00:21:54,399 And we have to go on what is written on the death certificate because there is no other way and 209 00:21:54,400 --> 00:22:00,040 the fact that it's actively recorded by S and then we can link it with the primary care record. 210 00:22:00,370 --> 00:22:05,800 That's that's quite a powerful linkage that isn't available in many other countries. 211 00:22:06,160 --> 00:22:12,280 So we always push back on that one because I think this is particularly looking at the cause of deaths. 212 00:22:12,550 --> 00:22:16,720 I think is is really important just to give us an idea of what people are dying from and when. 213 00:22:22,540 --> 00:22:33,370 So that was our paper. In 2019, we decided to publish the gender statistics in slightly more detail in the European Journal of Heart Failure. 214 00:22:33,700 --> 00:22:37,990 So we reported national trends in heart failure, survival for men and women. 215 00:22:39,190 --> 00:22:42,250 And and that was published the following year. 216 00:22:43,150 --> 00:22:50,799 And I think, again, because the dataset so big, you get very robust estimates for survival rates, splitting it by by gender. 217 00:22:50,800 --> 00:22:59,140 And what we found was that actually patients so female patients compared to male patients are diagnosed on average five years later. 218 00:23:00,820 --> 00:23:07,720 But then if we adjust, right, their survival is their mortality is actually lower. 219 00:23:07,900 --> 00:23:10,060 So their survival is better than men. 220 00:23:10,900 --> 00:23:18,880 These are infographics which we've started to produce for all of our papers because most people don't read a whole paper, 221 00:23:18,910 --> 00:23:24,760 unfortunately, cover to cover. But what we do is a visual representation of the study. 222 00:23:24,760 --> 00:23:31,480 So aim at the top, the key characteristics, the numbers that we're looking at, and then the key results in bright colours. 223 00:23:31,780 --> 00:23:36,910 And that just helps to get the message out from our research to a wider audience. 224 00:23:37,270 --> 00:23:47,139 So we put these on our website, we tweet them, we put them on Facebook, and we do blogs and things on on the mic part of the website, 225 00:23:47,140 --> 00:23:52,900 which is around diagnostics, just to try and increase the dissemination of our work. 226 00:23:52,900 --> 00:23:55,540 Because if we're going to spend years doing all this research, 227 00:23:55,540 --> 00:24:04,030 we want people to actually engage with it and see what we're doing because hopefully it's relevant to the community population. 228 00:24:06,200 --> 00:24:15,500 So what does this mean for my practice? So as I said, I work in a sort of suburban primary care. 229 00:24:15,560 --> 00:24:20,270 General practice is ATP, so we cover about 10,000 patients. 230 00:24:20,750 --> 00:24:26,450 So that means statistically we'll have about 20 patients newly diagnosed with heart 231 00:24:26,450 --> 00:24:30,890 failure each year and about 100 people on our list living with heart failure. 232 00:24:31,460 --> 00:24:34,880 So in that 20, that will be newly diagnosed. 233 00:24:34,910 --> 00:24:42,890 What our research shows is that around four of them, so 20% will die within the first year. 234 00:24:43,130 --> 00:24:50,720 And their patients that we need to identify early, we need to have them on our palliative care registers and gold standards framework, 235 00:24:50,720 --> 00:25:02,270 which is how we assess end of life care and identify people that are more likely to need end of life care because often these patients do get missed. 236 00:25:03,020 --> 00:25:09,020 Most of our registries focus on cancer diagnoses and cancer deaths, 237 00:25:09,200 --> 00:25:15,260 but actually people with heart failure also need high quality palliative care and end of life care. 238 00:25:16,670 --> 00:25:26,329 So at that 24, we're losing a year, but ten will survive the next five years and actually six will still be alive ten years later. 239 00:25:26,330 --> 00:25:38,360 So those six are people whose heart failure is potentially treatable, manageable, and it may be something else that causes them a problem in the end. 240 00:25:38,360 --> 00:25:41,599 So that's the difficulty in general practice. 241 00:25:41,600 --> 00:25:47,300 But also the joy of it is that you look at the patient overall, you don't just look at the one diagnosis, 242 00:25:47,660 --> 00:25:55,550 you look at what is wrong with them and how we can manage that individual optimally to optimise their pace, 243 00:25:55,760 --> 00:25:58,940 their quality of life as as well as their survival. 244 00:26:01,380 --> 00:26:06,570 So that's looking at our survival analysis and how we use big data for that. 245 00:26:06,870 --> 00:26:15,120 And I'd just like to spend the second half of the talk looking at diagnosis, which is what we're focusing our research on at the moment. 246 00:26:15,150 --> 00:26:19,370 So what does Big Data tell us about diagnosis? 247 00:26:21,830 --> 00:26:24,700 So just a little bit about the heart failure pathway. 248 00:26:24,710 --> 00:26:35,930 So as I said, patients with heart failure develop shortness of breath, ankles swelling, leg swelling, and they get incredibly fatigued and exhausted. 249 00:26:37,250 --> 00:26:45,649 And the diagnostic pathway relies on patients recognising the symptoms and seeking help for them. 250 00:26:45,650 --> 00:26:53,959 And as I said from my qualitative research, patients are often quite stoical at the beginning and didn't necessarily always 251 00:26:53,960 --> 00:26:58,870 appreciate that their symptoms could be linked to something like heart failure. 252 00:26:58,880 --> 00:27:04,910 So patients would say to me that they had put their breathlessness perhaps down to another condition. 253 00:27:04,910 --> 00:27:10,309 If they got lung disease, they put it down to that or almost normalise the symptom saying, 254 00:27:10,310 --> 00:27:14,810 Oh, it's just getting older, or put it down to all the medication that they were on. 255 00:27:15,080 --> 00:27:22,549 So there is in most of my interviews, there was a gap between patients getting symptomatic and actually seeing their GP. 256 00:27:22,550 --> 00:27:30,380 And I think there's an issue there about awareness and we need to raise awareness of heart failure more generally amongst the public. 257 00:27:31,040 --> 00:27:36,590 So when a patient comes to see the GP, it's then our responsibility to think of heart failure. 258 00:27:36,770 --> 00:27:41,930 So as you said, these patients often have several long term conditions or on lots of medications. 259 00:27:42,320 --> 00:27:50,120 So heart failure may be one of many things going through our minds when we're looking at why is this patient breathless? 260 00:27:50,780 --> 00:27:59,389 And we know from some research there is a delay between patients coming to see their GP and actually getting a diagnosis of heart failure because 261 00:27:59,390 --> 00:28:08,570 we can go down other diagnostic routes before we think about heart failure and then when we've considered heart failure is a possibility, 262 00:28:08,570 --> 00:28:12,350 we do a blood test which shows if the heart is under strain or not. 263 00:28:12,350 --> 00:28:21,139 And I'll talk about that in a second. And if that blood test is raised, then we need to refer the patient to get a definitive diagnosis. 264 00:28:21,140 --> 00:28:28,700 So heart failure is the diagnosis we make in primary care. If we think somebody's got heart failure, we need to refer for further imaging. 265 00:28:28,700 --> 00:28:38,210 So a heart scan called an echocardiogram and also a specialist assessment, and it's usually a cardiologist that would make the final diagnosis. 266 00:28:41,700 --> 00:28:46,190 So this is the nice guidance on testing for heart failure. 267 00:28:46,200 --> 00:28:52,110 So there's a blood test which goes up when the heart is under strain called not genetic peptide. 268 00:28:53,130 --> 00:28:56,630 There's two types this NT, Probnp and BNP. 269 00:28:56,640 --> 00:29:01,650 There are two parts of the same molecule and they're both not terrific peptides. 270 00:29:02,040 --> 00:29:05,680 The one that tends to be used more commonly now is anti probnp. 271 00:29:05,910 --> 00:29:12,250 And in the nice guideline, there's clear guidance for what we should do depending on the results of this blood test. 272 00:29:12,250 --> 00:29:17,610 So it's a simple blood test that we take along with blood tests we would do for kidney function, 273 00:29:18,570 --> 00:29:23,990 blood count, etc. if the level of treated peptides very high, 274 00:29:24,000 --> 00:29:34,049 so above 2025 with where to refer urgently for a patient to have a heart scan and a specialist assessment within two weeks. 275 00:29:34,050 --> 00:29:37,320 So similar to the two week wait cancer pathways. 276 00:29:37,950 --> 00:29:44,759 If it's between 402,000, we need especially assessment and echo within six weeks. 277 00:29:44,760 --> 00:29:52,620 But if it's below 400, then that means heart failure is unlikely and we should think about alternative conditions. 278 00:29:52,620 --> 00:30:00,150 So it can be a very helpful test to rule out heart failure if if you just want to make sure it's not that and it's probably something else. 279 00:30:01,780 --> 00:30:07,900 So not sure. I think peptides are released by the ventricles in response to pressure or fluid overload. 280 00:30:08,350 --> 00:30:12,460 They relax vascular smooth muscle and also induce a decrease. 281 00:30:12,610 --> 00:30:16,360 So they act like a lot of the drugs we use to treat heart failure. 282 00:30:19,570 --> 00:30:27,969 And the two types of not drastic peptide, a equally reliable intake gnosis and T Pro is slightly more stable. 283 00:30:27,970 --> 00:30:34,930 So if the blood test is sitting in a general practice for hours before they go off to the lab, that won't affect the anti pro results. 284 00:30:35,860 --> 00:30:40,149 And the thresholds are different though, so you need to know which one you're doing. 285 00:30:40,150 --> 00:30:50,410 So BNP less than 200 or anti pro less than 400 makes heart failure unlikely, but it doesn't differentiate between the two types of heart failure. 286 00:30:50,410 --> 00:30:52,060 So you need an echo for that. 287 00:30:54,660 --> 00:31:04,860 So this is a study where we looked at the association between the naturalistic peptide level at diagnosis and subsequently what happens to patients. 288 00:31:04,860 --> 00:31:09,290 So how likely they are to be hospitalised and how likely they are to die. 289 00:31:09,300 --> 00:31:13,360 And this was published in the journal Heart last year. 290 00:31:13,380 --> 00:31:18,990 So that's a journal that's read predominantly by cardiologists in the UK. 291 00:31:21,280 --> 00:31:27,999 So as we've said, heart failure is a malignant condition requiring urgent treatment, and the guidelines recommend that we do not treat it. 292 00:31:28,000 --> 00:31:32,320 Peptide Testing to prioritise referral for diagnosis. 293 00:31:35,490 --> 00:31:39,870 And we use CPR again between 2004 and 2018. 294 00:31:40,080 --> 00:31:45,900 And we had over 40,000 people with a new diagnosis of heart failure, 295 00:31:46,470 --> 00:31:52,050 half of whom were men and slightly older, 78 and a half was the main age at diagnosis. 296 00:31:52,410 --> 00:32:03,450 Again, we linked to the hospital episode statistics dataset and also to the OS civil mortality data to get a holistic view of what was happening, 297 00:32:03,450 --> 00:32:08,940 and particularly to answer this research question about who's going into hospital and who's dying of heart failure. 298 00:32:09,690 --> 00:32:17,490 And we looked at one year hospitalisation. So from a diagnostic code, how likely are people to go into hospital during that time? 299 00:32:17,760 --> 00:32:26,310 And also the one, five and ten year survival rates as we had with survival, but specifically in relation to the AMP level at diagnosis. 300 00:32:29,260 --> 00:32:37,560 So. As you can see from the survival curves, we've got time on the x axis, survival probability on the Y axis. 301 00:32:38,010 --> 00:32:43,560 And we looked at the different categories. So as we said, less than 400, it's unlikely to be heart failure. 302 00:32:43,680 --> 00:32:48,809 I think something else, 400, 2000 is what we call moderately raised. 303 00:32:48,810 --> 00:32:57,720 And then above 2000 is is a high level and they're the people that need referral and see within two weeks. 304 00:32:58,380 --> 00:33:03,840 And this survival curve just sort of confirms that the guidance is correct in 305 00:33:03,840 --> 00:33:09,389 that the sort of dotted blue line is those people that have an anti pro level 306 00:33:09,390 --> 00:33:14,790 above 2000 at diagnosis and they're the people that are much more likely to die 307 00:33:14,790 --> 00:33:20,610 of the condition than those who have a moderate or a normal anti probnp level. 308 00:33:25,190 --> 00:33:34,020 So overall in the cohort of 40,000 we found over half were hospitalised in the year following diagnosis, a huge burden for the health service. 309 00:33:34,170 --> 00:33:43,579 If you've got 50% chance of going into hospital a year after diagnosis and it was those people who had a very high anti pro BNP, 310 00:33:43,580 --> 00:33:52,250 so above 2000 that were more likely to have a heart failure related hospitalisation compared to those with a moderate natural tick peptide. 311 00:33:52,260 --> 00:33:55,760 So these are very high risk people and we need to get them seen, 312 00:33:55,760 --> 00:34:01,580 diagnosed and treated very quickly in order to prevent them going into hospital or having worse outcome. 313 00:34:03,560 --> 00:34:09,290 So we also looked at overall mortality rates between those with high or moderate MP. 314 00:34:09,290 --> 00:34:13,550 And as you can see, again, the mortality rates at one, one year, 315 00:34:13,580 --> 00:34:22,310 five years and ten years are all higher in that high anti probnp group compared to the moderate and TPO BNP group. 316 00:34:23,210 --> 00:34:27,850 We did a competing risk model to look at the risk of heart failure related deaths. 317 00:34:27,850 --> 00:34:31,790 So are people dying from heart failure or something else? 318 00:34:31,790 --> 00:34:42,620 And those with a high anti pro BNP had a 50% higher rate of heart failure related deaths compared to those with moderate. 319 00:34:42,630 --> 00:34:47,420 So these are people going into hospital with heart failure, dying of that heart failure. 320 00:34:48,740 --> 00:34:58,910 And interestingly, the median time between anti so natural peptide test and heart failure diagnosis was over 100 days. 321 00:34:59,210 --> 00:35:04,190 So nice recommend that patients following their test should be seen and diagnosed 322 00:35:04,190 --> 00:35:09,410 within two weeks if it's both 2000 but within six weeks for everyone else. 323 00:35:09,740 --> 00:35:17,750 And this is way outside of that. So patients are waiting a long time and I think that's an area where we need to shine 324 00:35:17,750 --> 00:35:24,680 a light and that's an area that requires improvement because if in primary care, 325 00:35:24,710 --> 00:35:29,720 I see a patient that might have heart failure. I do. And that genetic peptide test and it's high. 326 00:35:30,050 --> 00:35:40,700 If it's at both 2000, I need that patient to have the echo and see a specialist quickly because otherwise and what I have seen in clinical 327 00:35:40,700 --> 00:35:46,939 practice is patients have had their MP test and while they're waiting to get their scan and their right patient appointment, 328 00:35:46,940 --> 00:35:51,889 they're admitted to hospital because they're too unwell to to be in the community. 329 00:35:51,890 --> 00:35:57,110 So they go into hospital, have intravenous diuretics, and that's when they get their diagnosis. 330 00:35:57,350 --> 00:36:05,089 If we could make that diagnosis sooner and initiate treatment more quickly, we can maybe have prevented that hospital admission. 331 00:36:05,090 --> 00:36:11,960 And I think that's what they see this data show, is that this is what's going on and this is where we need some improvements. 332 00:36:13,130 --> 00:36:19,850 It's particularly important when hospitals are under such strain from COVID and trying to catch up after COVID. 333 00:36:20,600 --> 00:36:23,870 We need to keep people out of hospital unless they need to be there. 334 00:36:24,350 --> 00:36:28,970 And I think what we need is more capacity in cardiac imaging. 335 00:36:29,270 --> 00:36:32,510 Get in an echo, takes weeks and weeks where I work. 336 00:36:33,590 --> 00:36:38,990 So there is a real shortage of echo technicians to be able to do these specialist scans. 337 00:36:39,350 --> 00:36:48,889 So there's several points in the pathway where we need increased capacity in the system in order for the diagnostic process to work properly. 338 00:36:48,890 --> 00:36:55,310 And I think that's what these big data can show us and that's what we can take to policymakers to try and effect change. 339 00:36:59,380 --> 00:37:06,970 And my final example is our most recent paper looking at long term trends in nutritive peptide testing. 340 00:37:08,770 --> 00:37:19,990 So we've seen survival for heart failure is pretty poor 50%, five year survival rates that haven't really improved over time. 341 00:37:20,440 --> 00:37:28,599 And we've seen from the nice guidance that transit peptide testing is absolutely key to getting a diagnosis 342 00:37:28,600 --> 00:37:33,730 and getting on these effective treatments that we know can improve quality and quantity of life. 343 00:37:35,020 --> 00:37:43,930 So in this study, we wanted to look at what's happening with naturalistic peptide testing and what's what's the sort of trend with it over time. 344 00:37:44,320 --> 00:37:51,090 Because certainly when I qualified, we weren't using not tested peptide testing in the community. 345 00:37:51,100 --> 00:37:54,280 I didn't have access to it. And now we are. 346 00:37:56,190 --> 00:38:04,620 So the overall aim was to report the trends in testing and look at subsequent heart failure diagnosis over time. 347 00:38:04,890 --> 00:38:08,660 Again, we chose the same data as the previous study. 348 00:38:08,670 --> 00:38:13,950 It was all part of a CPD data code to answer three different questions. 349 00:38:13,950 --> 00:38:19,469 And the third question I won't talk about today, but will be at BGP in January. 350 00:38:19,470 --> 00:38:23,940 So that's our last bit to this, this big piece of work. 351 00:38:24,960 --> 00:38:33,420 But again, 14 year period, long period of time linked to the hospital episode statistics and OS mortality data. 352 00:38:33,720 --> 00:38:43,980 We had a bigger dataset this time, so 7.2 million patients we looked for not just peptide testing codes within their primary care records, 353 00:38:43,980 --> 00:38:53,850 and we had over a thousand practices in this. So a significant proportion of the UK population, probably 10 to 15% covered within this study. 354 00:38:54,570 --> 00:38:57,840 And what what has been happening with that peptide testing? 355 00:38:57,840 --> 00:39:04,590 So as you can see from 2004, we weren't really doing much testing because most of us didn't have access to it. 356 00:39:06,540 --> 00:39:16,229 I qualified in 2009. We got access in my practice in about 2011, and that really represents the national picture. 357 00:39:16,230 --> 00:39:26,460 So there's this sudden uplift in 2010, real increase in testing, both BNP, which is the blue line and anti pro BNP, which is the red line. 358 00:39:27,330 --> 00:39:30,510 But as you can see, and Tipos become much more the dominant test. 359 00:39:30,510 --> 00:39:38,159 So it depends what your lab offer as to what you can order, but anti pro is more stable over time. 360 00:39:38,160 --> 00:39:41,670 It's not metabolised by the newer drugs as well. 361 00:39:42,480 --> 00:39:52,620 So nice now recommending anti pro BNP testing if available, but obviously if your hospital lab is set up for BNP then that's fine too. 362 00:39:53,670 --> 00:39:58,559 And 2010 is the important year because that's when nice updated guidance previously. 363 00:39:58,560 --> 00:40:05,129 So I was on the 2018 update committee, but the previous update had been in 2010. 364 00:40:05,130 --> 00:40:11,490 And in that document they really strengthen the role of not treating peptide testing in the diagnostic pathway. 365 00:40:11,490 --> 00:40:15,000 And it's interesting to see this uplift in testing since then. 366 00:40:17,700 --> 00:40:22,799 We also looked at men and women again and in different age groups. 367 00:40:22,800 --> 00:40:26,580 So Blue is the oldest age group and this is appropriate. 368 00:40:26,580 --> 00:40:35,400 So it's by age. So there's more testing in older people and that's what you'd expect because the mean age at diagnosis is 76, 77. 369 00:40:35,640 --> 00:40:40,080 We should be testing more in older people because they're more likely to have the condition. 370 00:40:42,950 --> 00:40:51,490 And similarly, we looked at ethnicity. So not much difference between ethnic groups and deprivation. 371 00:40:51,500 --> 00:40:58,280 So it's good to say that in the most deprived group, that's where the most testing is. 372 00:40:58,700 --> 00:41:03,559 And heart failure prevalence is higher in deprived populations. 373 00:41:03,560 --> 00:41:09,680 But sometimes you see health inequalities where actually the least deprived, they're getting the most testing. 374 00:41:09,830 --> 00:41:18,530 But actually, from this big data, that wasn't the case. And we are testing the people that need to be tested, which is good. 375 00:41:20,980 --> 00:41:29,980 And we we get a number. So the natural peptide level within the big data so we can calculate the median level at 376 00:41:29,980 --> 00:41:35,080 time of heart failure diagnosis and we can look at that for each year of the 14 years, 377 00:41:35,080 --> 00:41:40,110 15 years in the study. And as you can see, it's pretty consistent. 378 00:41:40,120 --> 00:41:46,659 So the top graph, so those with BNP tests with and with that heart failure and the bottom is 379 00:41:46,660 --> 00:41:52,809 anti pro with heart failure without and there hasn't really been much change. 380 00:41:52,810 --> 00:42:04,120 So the median level of anti pro BNP at diagnosis is around 1200, which is actually quite high because the threshold for referral is only 400. 381 00:42:04,510 --> 00:42:13,360 So that means that we are still getting people that have more advanced heart failure then being close to that threshold. 382 00:42:13,420 --> 00:42:20,799 So that was an interesting finding because perhaps we need to be testing people a bit earlier and we need 383 00:42:20,800 --> 00:42:27,879 to think about how we might be able to do that in order to catch people sooner in the disease process, 384 00:42:27,880 --> 00:42:37,420 to be able to treat them before they land open. And because they're too breathless and they need intravenous diuretics to to make them feel better. 385 00:42:39,390 --> 00:42:44,910 So these were the main findings that we concluded. So there has been this real increase in testing. 386 00:42:44,910 --> 00:42:48,060 So we are using more natural peptide tests in primary care. 387 00:42:48,390 --> 00:42:53,400 We using them in appropriate populations. So older people, more deprived people are getting tested. 388 00:42:54,330 --> 00:42:59,129 We found the heart fake fairly detection rate was around constant, so around 10%. 389 00:42:59,130 --> 00:43:04,590 So one in ten people who have enough to take a test will get a diagnosis of heart failure. 390 00:43:05,010 --> 00:43:09,540 And that hadn't really changed. Whereas in cancer we're testing a lot more people. 391 00:43:10,020 --> 00:43:16,919 So the detection rates are much, much lower because most people tested on having a diagnosis of cancer, 392 00:43:16,920 --> 00:43:22,320 whereas in Hertfordshire that has stayed constant. So perhaps we need to be thinking about testing more people. 393 00:43:22,890 --> 00:43:30,090 And surprisingly, in the last period of the study, still up to 2017, so pre-pandemic, 394 00:43:30,090 --> 00:43:38,070 but recently only one in four people had a natural peptide test prior to that heart failure diagnosis. 395 00:43:38,610 --> 00:43:44,220 So three quarters of people who were diagnosed with heart failure hadn't had a electrolytic peptide test beforehand. 396 00:43:45,540 --> 00:43:48,870 So even though there has been this really big increase in testing, 397 00:43:49,470 --> 00:43:54,810 we probably need to look at more testing in primary care to try and facilitate a 398 00:43:54,810 --> 00:44:00,480 diagnosis at an earlier and more treatable stage before people end up in hospital. 399 00:44:03,620 --> 00:44:13,069 So overall, my lessons from Big Data, I think as I've said, it's a really powerful research tool to be used. 400 00:44:13,070 --> 00:44:16,549 I reflects better than any other methodology, 401 00:44:16,550 --> 00:44:23,900 really real life practice and what is happening in real life in the million consultations in general practice each day in the UK, 402 00:44:24,710 --> 00:44:30,110 I think the downsides are, as I've said, we use it for routine clinical care. 403 00:44:30,110 --> 00:44:35,719 It's not collected in the same way as we would for robust or qualitative work. 404 00:44:35,720 --> 00:44:41,760 It's just not using the same research methods, but coding standards are looked at and. 405 00:44:41,960 --> 00:44:49,400 ROPER So I think it's still a reliable data source, but we need to acknowledge the limitations whenever we report this work. 406 00:44:50,180 --> 00:44:57,919 I think the really key thing for me is always bringing the question back to the patient, because these data sets are so big, 407 00:44:57,920 --> 00:45:05,590 you can look at so many things and get so many numbers, but actually what what's important and what matters. 408 00:45:05,930 --> 00:45:15,890 So all three examples I gave the research question idea came from patients that I had talked to, either in our peer group or in my clinical practice. 409 00:45:16,250 --> 00:45:22,370 And that's what then drove the big data analysis and the write up and the reporting of the results. 410 00:45:22,370 --> 00:45:26,690 And I think without that focus we can get a bit lost in the big data.