Oct 3, 2016
Welcome to Circulation on the Run, your weekly podcast summary and backstage pass to the journal and its editors. I'm Dr. Carolyn Lam, Associate Editor from the National Heart Center and Duke National University of Singapore.
Today, we will be discussing an interesting Danish nationwide cohort study on the return to the workforce following first hospitalization for heart failure, but first here's your summary of this week's journal.
The first paper addresses a common question asked by patients who have survived an aortic dissection. Will this happen to me again? First author, Dr. Isselbacher, and corresponding author, Dr. Lindsay, and investigators of the International Registry of Aortic Dissection investigated this in the largest systematic analysis to date of patients presenting to hospital with a recurrent aortic dissection.
In this large registry, the authors identified 204 patients with recurrent aortic dissection and compared these to 3624 patients in the registry with an initial aortic dissection. They found that patients with recurrent dissection were more likely to have Marfan syndrome, but not bicuspid aortic valve. Descending aortic dimensions were greater in those with recurrent dissections than those with only an initial dissection, and this was independent of the sentinel dissection type. In multivariable analysis, the diagnosis of Marfan syndrome was independently predictive of a recurrent aortic dissection with a hazards ratio of 8.6.
Furthermore, they found that the patient's age at the time of first dissection correlated with the anatomic pattern of aortic involvement. In younger patients, dissection of the proximal aorta tended to be followed by dissection of the distal aorta, whereas the reverse was true among older patients suggesting divergent mechanisms of disease.
In summary, therefore, this study shows that recurrent aortic dissection while in common does occur and in fact affected 5% of those in this registry. The data really illustrate the importance of syndromic forms of aortic dissection and suggest that occurrence of a recurrent dissection should raise suspicion of a genetic etiology of aortic disease.
The next study provides pre-clinical data suggesting that counteracting increased hepcidin may be a therapeutic target for treatment of intracerebral hemorrhage. In this study from first author, Dr. Xiong, corresponding author, Dr. Yang, and colleagues from Xinqiao Hospital, the Third Military Medical University in China, parabiosis and intracerebral hemorrhage mouse models were combined with in vitro and in vivo experiments to investigate the roles of hepcidin in brain iron metabolism after intracerebral hemorrhage. Hepcidin in an important iron regulatory peptide hormone that controls cellular iron efflux.
The authors found that increased hepcidin-25 was found in the serum and astrocytes after intracerebral hemorrhage. In hepcidin-deficient mice with intracerebral hemorrhage, there was improvement in brain iron efflux and protection from oxydative brain injury and cognitive impairment, whereas, the administration of human hepcidin-25 peptide in these mice aggravated the brain injury and cognitive impairment.
In vitro studies showed that increased hepcidin inhibited intracellular iron efflux in brain microvascular endothelial cells, but this phenomenon was rescued by a hepcidin antagonist. Additionally, toll-like receptor 4 signally pathway increased hepcidin expression, whereas, a toll-like receptor 4 antagonist decrease brain iron levels and improve cognition following intracerebral hemorrhage.
In summary, the study showed that increased hepcidin expression caused by inflammation prevented brain iron efflux and aggravated oxidative brain injury and cognitive impairment, thus, counteracting increased hepcidin maybe a mechanistic target to promote brain iron efflux and attenuate oxidative brain injury following intracerebral hemorrhage.
The next basic science paper provides fascinating insights into the similarities between advanced atherosclerotic lesions and tuberculous granulomas, both of which are characterized by a necrotic lipid core and a fibrous cap. First author Dr. Clement, corresponding author Dr. Mallat, and colleagues from the University of Cambridge Addenbrooke's Hospital in United Kingdom looked at the C-type lectin receptor 4E which has been implicated in the events leading to granuloma formation in tuberculosis.
The authors hypothesized that the same C-type lectin receptor 4E may be involved in the formation of atherosclerotic lesions as well. They addressed this hypothesis by examining the impact of receptor activation on macrophage functions in vitro and on the development of atherosclerosis in mice. They showed that C-type lectin receptor 4E was expressed within human and mouse atherosclerotic lesions and was activated by necrotic lesion extracts. The receptor signaling in macrophages inhibited cholesterol efflux and induced endoplasmic reticulum stress responses leading to the induction of proinflammatory mediators and growth factors.
Furthermore, repopulation of LDL receptor-deficient mice with C-type lectin 4E receptor-deficient bone marrow reduced lipid accumulation, endoplasmic reticulum stress, macrophage inflammation, and proliferation within developing arterial lesions that's significantly limiting atherosclerosis.
In summary, this paper shows that C-type lectin receptor 4E orchestrates major pathophysiologic events during pluck development and progression, and thus, provides a mechanistic explanation for the close association between necrotic lipid core formation and the development of inflammatory advanced atherosclerotic lesions.
The last paper examined the impact of optimal medical therapy in the dual antiplatelet therapy or DAPT study. In this paper from first author, Dr. Resor, corresponding author, Dr. Mauri, from the Brigham and Women's Hospital in Boston and colleagues, authors sought to assess the impact of optimal medical therapy use on long term patient outcomes and on the treatment benefit and risk of continued dual antiplatelet therapy, and they did this using data from the DAPT study which was a randomized placebo control trial comparing 30 versus 12 months of final prudent therapy on the background of aspirin after coronary stenting.
Optimal medical therapy was defined as a combination of statin, beta blocker, and angiotensin-converting enzyme inhibitor or angiotensin receptor blocker used in patients with an ACC/AHA class 1 indication for each medication. Endpoints included myocardial infarction, major adverse cardiovascular and cerebral vascular events or MACE, and GUSTO moderate or severe bleeding events.
Of 11,643 randomized patients with complete medication data, 63% were on optimal medical therapy. Between 12 and 30 months, continued final prudent therapy reduced myocardial infarction compared to placebo in both groups and had consistent effects on the reduction in MACE, and an increased bleeding regardless of the optimal medical therapy status. In other words, the P for interaction was nonsignificant for these comparisons.
Importantly, patients on optimal medical therapy had lower rates of myocardial infarction, MACE, and bleeding compared to patients not on optimal medical therapy. Rates of stent thrombosis in death did not differ. The take home message is therefore, that more emphasis on the use of optimal medical therapy after coronary stenting is needed, but the decision to continue dual antiplatelet therapy beyond 12 months should be made irrespective of the optical medical therapy status.
Those were your summaries. Now, for our feature paper.
Our feature paper today discusses a really important, but frankly, often neglected outcome in heart failure, and that is return to the workforce following first hospitalization for heart failure, and I'm really pleased to have the first and last author of this really special Danish paper, Dr. Rasmus Rorth and Dr. Soren Kristensen, both from the University of Copenhagen, here to join me today. Hello, gentlemen.
Hello and thank you for having us, Carolyn.
As a very special third guest, we actually have editorialist, Dr. Martin Cowie from Imperial College London as well. Hi, Martin.
Hi, Carolyn. Nice to be part of the conversation.
This is going to be so fun. Let's get straight into this. Rasmus, maybe you could start by telling us. This return to work concept is hardly addressed in guidelines, it's so important, and yet, you are one of the first if not the first to take a look at it. What inspired you to do this?
First of all, we are very inspired to work with heart failure because heart failure is a common costly, disabling, and deadly disease, and furthermore, information on young patients with heart failure is vast. We know that they have a high hospitalization rate and a low mortality rate compared to all the patients. We also know from some of the big trials that young heart failure patients report low quality of life. Therefore, we wanted in this study to examine return to work for a number of reasons.
First of all, it gives off some information of the patient's performance basis and we get some information of their quality of life and mental status, and one more reason that is not that common for us as clinicians to think about is also for society, the economic burden these patients play in the society, and all of these reasons inspired us to get into this exciting field.
I really appreciated that you did this because the patients that I see here in Asia are on average 10 years younger than the heart failure patients that have been seen in other European registries and so on, so it is a very, very important aspect because my heart failure patients are often the sole breadwinners of families here. Could you, maybe, Soren, share with us what are those unique resources that you manage to look at this in such detail in the Danish registries?
The unique quality in Denmark is that you have the unique identifying numbers for all the citizens of Denmark and these numbers are not only used in the health systems. They're also used for administrative registries for tax paying and for state funds and pensions. We were able to link information from the hospital discharge registries with information on tax paying and whether or not people are getting pensions. In that way, we could follow all patients who stayed in Denmark at least to see whether or not they were receiving any funds, any pension, or sick leave money, or things like this from the state, or whether they upheld a position. That's what makes the Danish system a bit unique, that we have this ability to track the patients across all the fields of society and also that we have a public health system which all patients are included in, and the private sector is negligible in Denmark.
Wow. Listening to that is making all epidemiologist everywhere really drool. That is such a precious system to look at this. What were your main findings, Rasmus?
Maybe I should explain a bit about the setting. This is a nationwide-based study starting where we identify the patient with the first heart failure hospitalization, 18 to 60 years in the period from 1997 to 2012, and we followed them onwards. In our primary analysis, we only included patients in the workforce, that means either employed or available for the labor market at time hospitalization. That is the setting of the study.
Could you share your main findings and your take home messages?
Our primary outcome of this study is that after one year, 25% of the patients did not return to the workforce and we had a low mortality, only 7% died.
Twenty-five percent didn't return to the workforce?
Yeah, and keeping in mind, Carolyn, these are patients in the workforce at their first hospitalization and also young patients. Our take home patient from this paper is that patient in the workforce at heart failure hospitalization had a low mortality for the high risk of [inaudible 00:13:41] from the workforce at one year of followup. Furthermore, we look at some association effect associated with returning to work, and we found that young age, male sex, and high level of education were associated with high likelihood of returning to work.
Martin, you wrote just a beautiful editorial. I have to say I was chuckling and enjoying it as I read it. I could hear your voice in it. What do you make of these results in the interpretation?
I was really pleased to see something published by this really important topic that is largely ignored, and as you said in your introduction, the guidelines, if you read them you'll think that nobody of working age ever develops heart failure. There's no mention at all about return to work. There's no mention of the kind of urgent need to be able to provide people with the counseling about the heart failure and how it might impact their work, and also, no interaction, no mention of interaction with employers to tell them, "Yes, this person have this condition, but actually, could do their job or stay in the same job," or "How we can help support them?"
I think this article which is so good to see graded publish in Circulation and I think we have to see it in the context of other occupational rehabilitation work which shows that if you don't get people back to work quite quickly after a major event in their lives, then you'll never get them back, and that's got huge consequences for them in their mental health, their economic, social, family, and never mind the healthcare system. It's really nice to see this work and I hope many people read it and quote it.
Martin, you've been to Asia. You know that our patients are strikingly young, but I wonder, do you think these results are extrapolatable outside of Denmark?
I think this comment and not an editorial, Denmark, of course, is a relatively small country. It's wealthy. It's different from the states, but it's very different from Asia as you say, so lots of heart failure patients in Asia are young, of working age, and quite often, their families depend on them.
I think the tactics may have to be different to different countries, but the general principles are the same that we, as a heart failure team, as heart failure doctors, have to think about the person not just in terms of the left atrium and left ventricle, or even of the whole body function, but actually, what is their role in their family, what are they trying to achieve in life, how can we support them about way, because otherwise, we're really failing our patient.
I think, in Asia even more than in some wealthy, rich countries where there's a lot of safety nets, it's really important. I'd be interested in your comment, Carolyn, on what you think we can do to improve right across the world in terms of occupational rehab.
First, I think it begins with awareness and that's why I just wanted to tell Soren and Rasmus how much I enjoyed this paper and I will be citing it because I think it's so important especially in the younger heart for the community, but can I ask you, Soren or Rasmus, have these findings changed your practice in any way or to be even more provocative, do you think that maybe return to work should be a benchmark to evaluate heart failure programs?
Martin also points out that, first of all, we need to shed light on this hidden fact of heart failure, and afterwards, I think it's also a very good policy metrics to use in the future to see how our patients do.
Are there efforts in Denmark to improve this as a yardstick?
I'm quite sure that, by large, it's not really registered who is working, who is not working there. There's not much attention to it. We're all focusing very much on the performance of the patient of the NYHA class and so on, so I think we should put more emphasis on this issue and we should, as Martin also added, that we should discuss with the patients if they could change their job or their positions in some ways to better cope if they lost some of their performance, because we're both think and we both agree with Martin that it's a huge quality of life to be able to maintain your job in one way or the other, and we should definitely put more focus on that, but I'm afraid to say that I don't think we put much focus on it in Denmark at this time, but hopefully, we will.
I think you're right, the attitude have to change across the world, don't they, and they start with the heart failure team and the patients because I think most doctors and nurses and patients assume diagnosis of heart failure, that means really nothing can be the same again, but we really should be trying to return people to their optimal function, and I'm sure we can do a lot more, but perhaps, we need to upscale the workforce and knowing about the key things about occupational counseling, and maybe also [inaudible 00:18:30] interact with employers a little bit more without patient's permission to give them the confidence to have this person re-enter the workforce in a supported way because I'm sure the employers value many of these people and would be pleased to see them still in the workforce.
Exactly. I even think that could be like a fair way of trying to help the patient by relieving them from their job, which is actually will be a big mistake for some patients [inaudible 00:18:54] as a physician to help them with making sure they don't have to return to their job and fill out the statements and everything, but this may not be the best for the patient.
Gentlemen, I have enjoyed this conversation so much. Thank you for taking the time to discuss this very important paper.
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