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Qualitative research
Research
Long-term psychological consequences of symptomatic pulmonary embolism: a qualitative study
  1. Simon Noble1,
  2. Rhian Lewis2,
  3. Jodie Whithers2,
  4. Sarah Lewis3,
  5. Paul Bennett2
  1. 1Marie Curie Palliative Care Research Group, Cardiff University, Cardiff, Wales, UK
  2. 2Department of Clinical Psychology, Swansea University, Swansea, Wales, UK
  3. 3Department of Haematology, Nevill Hall Hospital, Abergavenny, Wales, UK
  1. Correspondence to Dr Simon Noble; simon.noble{at}wales.nhs.uk

Abstract

Objective To explore the psychological consequences of experiencing symptomatic pulmonary embolism (PE).

Design Qualitative interview-based study using interpretative phenomenological analysis.

Setting Outpatients who attended an anticoagulation clinic in a district general hospital.

Participants Patients attending an anticoagulation clinic following hospital admission for symptomatic PE were approached to participate. A total of 9 (4 women, 5 men) of 11 patients approached agreed to be interviewed. Participants were aged between 26 and 72 years and had previously experienced a PE between 9 and 60 months (median=26 months, mean=24 months).

Intervention Audiotaped semistructured qualitative interviews were undertaken to explore participants experiences of having a PE and how it had affected their lives since. Data were transcribed and analysed using interpretative phenomenological analysis to identify emergent themes.

Results Three major themes with associated subthemes were identified. Participants described having a PE as a life-changing experience comprising initial shock, followed by feeling of loss of self, life-changing decisions and behaviour modification. Features of post-traumatic stress disorder (PTSD) were described with flashbacks, hypervigilance and intrusive thoughts being most prevalent. Participants identified several areas of support needed for such patients including easier access to support through information giving and emotional support.

Conclusions Long-term consequences of venous thromboembolism go beyond the physical alone. Patients describe experiencing symptomatic PE to be a life-changing distressing event leading to behaviour modification and in some PTSD. It is likely that earlier psychological intervention may reduce such long-term sequelae.

  • QUALITATIVE RESEARCH
  • VASCULAR MEDICINE

This is an Open Access article distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 3.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/3.0/

https://doi.org/10.1136/bmjopen-2013-004561

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    Strengths and limitations of this study

    • This is the first time the psychological consequences of symptomatic pulmonary embolism (PE) have been explored.

    • This paper highlights an unmet clinical need.

    • This paper is of relevance to a breadth of health professionals.

    • This paper gives patients a voice.

    • The patients were recruited from a single site.

    • While appropriate in number for interpretative phenomenological analysis, the numbers of participants are small.

    • The data cannot be generalised among all patients with PE but highlights the need to explore the area further.

    Venous thromboembolism (VTE), clinically presenting as deep venous thrombosis (DVT) or pulmonary embolism (PE), remains a major cause of morbidity and mortality worldwide, affecting 1 in 1000 patients annually.1 The long-term physical consequences of VTE are well documented; post-thrombotic syndrome (PTS) complicates between 25% and 50% DVT cases2–5 and 0.4% and 4% of patients who experience PE will develop chronic thromboembolic pulmonary hypertension (CTPH).6–8 Both these complications represent a considerable healthcare burden. Patients with PTS may not only require long-term compression stockings but also endovascular surgery if symptoms prove refractory.9 For patients who develop CTPH, medical therapy is yet to demonstrate any survival advantage leaving pulmonary thromboendarterectomy as the treatment of choice.10 ,11 However, only half of the patients will qualify for surgery and, of the remainder, 50% are likely to die within a year if their mean pulmonary arterial pressure exceeds 50 mm Hg.11 ,12

    The long-term sequelae following acute VTE go beyond the physical alone. The development of PTS appears to have a negative impact on quality of life (QoL) in patients experiencing VTE.13 ,14 Using the Venous Insufficiency Epidemiologic and Economic Study quality-of-life questionnaire (VEINES-QOL) and its validated subscale of 10 items on venous symptoms (VEINES-Sym), patients with PTS were shown to have significantly worse disease-specific QoL scores than those without PTS (p=0.003), which worsened significantly with increasing severity of PTS.13 ,14 Furthermore, the development of PTS is considered major determinant of a patients’ health-related QoL 2 years after VTE.14

    While the physical consequences of VTE have been extensively reported, the possible impact of VTE on patients’ psychological and emotional well-being has received less attention. Such work has involved the use of validated QoL tools and has focused on the chronic consequences of deep vein thrombosis and less so on pulmonary emboli.15–17 Other common and potentially life-threatening conditions such as cancer and myocardial infarction have been researched extensively with clear evidence that such illnesses can result in significant psychological morbidity. To date, no qualitative studies have investigated the impact of VTE on everyday life.

    The experience of any health-related crisis is likely to result in some form of emotional distress presenting in a variety of forms including worry, anxiety, intrusive ideation and dysphoric mood, among other negative emotional reactions.18 ,19 This appears most pronounced in medical events that pose a significant threat to life and can manifest as anxiety, anger, depression and even symptoms of post-traumatic stress disorder (PTSD).1 ,20–22 Historically, PTSD has been associated with experiences of war, rape or attempted murder, where the individual is exposed to an external threat to the physical integrity of themselves or others. However, research now suggests that PTSD may also arise from internal physical experiences, particularly those associated with a direct or imminent threat to life.23 ,24

    Life-threatening and traumatic medical events are those most likely to cause psychological distress and behavioural changes associated with symptoms of PTSD.25 Risk for PTSD is heightened by the perception of uncertainty and/or unpredictability associated with the traumatic medical experience and worsened where the patient believes adverse outcomes to be inevitable or largely uncontrollable.26 ,27 Since VTE is a potentially life-threatening condition that often occurs in previously well patients, coupled with the uncertainty of recurrence it is possible that such patients are at increased risk of emotional distress, especially those who have experienced major PE.28 We therefore conducted a study to explore the psychological impact of VTE in patients who had experienced a major symptomatic PE.

    Methods

    This study was undertaken using qualitative methodologies, which have previously been used to evaluate patient experience and clinician attitudes regarding VTE management.29–31

    Patients attending a dedicated haematology/thrombosis clinic, within a district general hospital, were sequentially screened for inclusion into the study and invited by letter to participate. All eligible patients were invited to participate.

    Inclusion criteria:

    • Aged between 18 and 70 years of age;

    • Patients who had experienced a symptomatic PE which resulted in admission to hospital;

    • Able to consent and participate in a 30 mininterview.

    Exclusion criteria:

    • Presence of cancer;

    • Known history of mental illness or psychological distress prior to PE.

    Semistructured interviews were carried out over a 12-month period by two female researchers (RL and JW) as part of an MSc research project under the supervision of PB and SN. Both researchers were experienced in the field of clinical psychology and trained in conducting qualitative research. Following initial pilot testing, the interviews were conducted within patients’ homes and guided by a prompt list to ensure that the same issues were discussed at each interview. Researchers had no prior relationship with participants or declared clinical interest in VTE management. Data were elicited on the following:

    • There experience of suffering a major PE;

    • How they felt this had affected or influenced their day-to-day lives in terms of:

      • Routines and activities;

      • Feelings, attitudes and beliefs about themselves.

    To facilitate this, questions were open-ended with the use of prompts to probe further into issues, which arose as significant or meaningful to the participant. Interviews were digitally recorded and transcribed verbatim. Field notes were also taken. Interviews took approximately 30 min each.

    Analysis

    The analytic framework for this qualitative study was based on interpretative phenomenological analysis (IPA).32 IPA aims to explore how participants make sense of their experience but is also interpretative, recognising the researcher's conceptions, and experience, as brought to the analysis.

    The data were analysed in the following stages:

    • The first transcript was read line by line and annotated with initial comments.

    • Initial comments were grouped into themes.

    • Connections between themes were developed until an organised master list and thematic rationale was achieved.

    • New themes were tested against the previous transcripts as non-recurring themes were tested against following transcripts. Connections across cases were noted to identify a set of superordinate themes for the group.

    A coding framework for emergent themes was then developed and applied across the data corpus. Initial coding was undertaken independently by RL and JW and then validated by SN and PB.

    Results

    Participant characteristics

    Of 11 eligible participants invited, 9 (5 men and 4 women) agreed to participate in the study. Previous IPA-based studies within the field of health psychology have recommended a minimum of three to six participants to achieve saturation of themes.32 Patient characteristics are summarised in table 1. Patients were aged between 26 and 72 years (median=44, mean=45). All patients had been previously hospitalised following a symptomatic PE between 9 and 60 months (median=26 months, mean=24 months). The majority of patients presented with progressive dyspnoea. Two described sudden onset symptoms and two patients had cardiovascular compromise from the PE. Two major themes were identified with associated subthemes (figure 1). Major themes with associated subthemes identified are summarised in figure 1 and were: PE as a life-changing event, development of PTSD and identification of support needs.

    View this table:
    Table 1

    Characteristics of participants

    Figure 1
    Figure 1

    Major themes and associated subthemes.

    Major theme 1: life-changing event

    Patients viewed their experience of a PE as a life-changing event, which had significant impact on their emotions, behaviours and how they viewed themselves and the future. Having gone from being healthy individuals with no major comorbidities patients reported ongoing and significant emotional distress following their diagnosis. The major components of this distress came from the initial shock of the diagnosis and ongoing uncertainty of the future.

    Shock/distress at uncertainty

    Patients described uncertainty as a prominent source of emotional distress and discontent, as well as having impacted on how they behave in their day-to-day lives. Uncertainty was most commonly associated with feelings of worry and anxiety in relation to ‘not knowing’ and concerns about treatment, their future health and life expectancy and the physical effects of their condition on their day-to-day life. For example, patients often referred to feelings of worry and anxiety in relation to not knowing whether or when they would experience another major PE. So I think having to live with that, the uncertainty, has caused me to worry a lot because no one can say for definite that A, it will never happen and B if it did it would never get to the level where next time I wouldn't be so lucky. I think that's the hardest part, just not knowing if or when it's ever going to happen again. 2F But, it was just a bit, a bit of a shock because obviously, I am young, and it doesn't really happen to people, my age, without you know, actual problems with the blood… 8F It got me down first of all, it, bit of a shock, ‘cause I wouldn't expect it to be a clot, I thought it was just a nasty bruise… 9M

    Patients also expressed emotional distress in relation to not knowing the cause of their major PE or why they have experienced a decrease in physical fitness. I just couldn't understand why it had happened to me. Why me? It was awful not knowing what had caused it. 2F

    In a number of cases, patients described feelings of worry and anxiety and consequent restriction or withdrawal from physical activities due to having become ‘hypervigilant’ to bodily sensations due to uncertainties about not knowing or understanding the meaning or implications behind experiencing such bodily sensations. Patients referred to discerning bodily sensations such as breathlessness or increased heart rate, often experienced with attempts at physical activity as being similar to their original symptoms and thus interpreted to indicate a negative, catastrophic outcome (eg, recurrence or death from major PE). Frightened if I'm honest, because…um…I wasn't sure what it was, I thought it was pleurisy so, initially I just thought well, it's pleurisy, it's painful, and it's fine, but once I knew it was blood clots, and the Consultant said, sometimes these damage the outside of the heart, I was scared, in fact, when the Consultant left, um, and I was on my own, I got a bit tearful, it was, I thought, well, this is life threatening. 7M I slightly panicked a bit later on when I sort of recovered, because I had felt very dizzy at that point, the nurse explained to me that my heart rate dropped to thirty and that's when I first probably realized you know, the potential outcome could be, very bad. 6M

    Loss of self

    Participants reported feelings of losing who they were, in particular with respect to no longer undertaking activities or behaviours that they previously identified as part of their core characteristics. The loss of self was considered more profound owing to the suddenness of the PE event from which they attributed the loss of self to originate. For some, the loss of self appeared to originate from the physical restrictions they found imposed on them from the PE itself. For others the changes in activities resulted from being anticoagulated, thus needing to avoid activities that had a high risk of trauma and bleeding. I just find it difficult to comprehend that overnight I went from being fit, doing most things that people are able to do at my age without any problems at all, and in the twinkling of an eye reduced to not even being able to walk even ten yards across a ward to the toilet. I just don't see myself as fit anymore. 4M Since I've had this he hasn't mentioned taking over the business because he's seen such a change in me that he knows that I'm not capable of doing it. And deep down, that hurts me more than anything. 3F It hurts me to think that they don't see me as the fun, active mum I used to be, and I think they do resent me for it. 3F It's had a bit of a deeper effect on me really, because, I've had to stop all the things I used to do, I was really into rugby, which is obviously quite a contact sport, um…surfing, um, and karate which is full contact as well, and my whole lifestyle was, sort of a, so I've had to stop everything… 6M I was told I can't really drink much and that's all I used to do on a Saturday after rugby and, so socially I'm not as active as I was… 6M I hate it really…, really upsetting really ‘cause I can't do anything I used to do, like doing. 9M

    Change in focus or direction

    All participants reported their experience of PE to have affected how they viewed and approached the future. Some adopted a fatalistic or nihilistic approach, suggesting they no longer felt in control of their destiny, which was at the mercy of future thrombotic events. It doesn't give you a very good outlook does it? I try not to think ten years time, twenty years time you know what I mean? 3F Ninety eight percent of the time I'm very fatalistic about it all now…I've kind of accepted my lot.5M

    Many considered their experience as an opportunity to re-evaluate their lives and take positive steps to optimise their future. Some described a new-found appreciation of what was important to them, while others had made changes to their careers or their lifestyles. But then I guess I'm lucky to still be alive. You know I'm still here…I've just got to accept that as much as it hurts, I want to see my girls grow up…So I've just got to be positive and grateful for what I have got. And thinking like that has helped me to go on with my life. 3F I've gone into care work now which is great because I've got the strength to help people and its nice that I can relate to people who've had strokes and such because I think ‘I ain't half lucky’, you I feel so blessed and lucky that I'm still here to help people you know. So for me its made me have a sort of different outlook on life but sort of more positive.” 3F But, um, I do consider things to be a bit more, *pause* cherishing, have some cherished moments *laughs* especially straight after…now, I just feel like I'm back to normal…but I'm trying to make the most of, what I've got…which isn't a lot… 8F I've um, looked at what do I need to do to improve my chances of, um, living a healthy lifestyle…so I've been now to see a nutritionist for healthy eating…I don't drink um, more than 2–3 units a day, and I'll have a couple of days off which I wouldn't have done before, and I'm trying to look at my food intake and what I'm eating, to try to lose weight…so I'm just trying to be more sensible about my eating and drinking habits and being more focused on my exercise. 7M

    Avoidance behaviours

    Participants frequently described a modification in their day-to-day behaviours. They avoided any activity they perceived could precipitate a further PE and those receiving anticoagulation avoided anything that might increase their risk of bleeding complications. Modification of physical activity and exertion was the commonest behaviour change in order to minimise exposure to potential physical trauma. I was quite outgoing and robust…feel like I've gone more timid…I don't get involved in anything…I'm afraid I'll bang my head…I just really, really refrain from doing much. 6M I'm certainly very careful, I don't get any cuts that you know, are unnecessarily from silly little things, so you'd be careful around being um, uh…when I was out on the road bike cycling or you know, sometimes I wouldn't put my helmet on, now I always put my helmet on, so it's just made me be a bit more careful around what I'm doing incase I you know, bleed or um, or something happens from that. M7

    Major theme 2: PTSD

    PTSD is characterised by a group of symptoms including flashbacks, avoidance behaviours, numbing of memories and hyperarousal, which continue beyond a month after the traumatic event.33 ,34 Almost all participants volunteered symptoms suggestive of PTSD, some describing symptom clusters which suggested a significant degree of functional disability due to the condition.

    Flashbacks

    Flashbacks to, and memories of, the initial PE experience were common. Ongoing anticoagulation, be it self-injecting low molecular weight heparin, taking oral anticoagulants or having blood tests acted as profound triggers to flashbacks and reminders of their perceived “near-death experience”. All these sorts of things; its brought back to you all the time even when your not consciously thinking about it, its brought back to you all the time. 5M And then I reverted to injecting myself and then that then carried on but it was just a constant reminder of what had happened, even now, although its become routine, it just makes me think how close I came to almost dying, to how ill I was. 4M For instance it might be time to my injection and it'll just all come back to me. The worries, will it happen again, will I be so lucky next time? 2F

    While some reported the content of the flashback episode to be short-lived, others experienced a more protracted experience reliving the entire distressing episode. I'll go through the whole thing. Like it will run from start to finish like a movie. Its very hard to switch off once I've started thinking about it, it has to play out if you like 2F

    Numbing of memories

    Several participants recalled a blunting of their emotion during the experience with some disassociation with reality. …some sense which it doesn't seem real… 5M …seems like, as if it kind of wasn't real… 8F

    Others described the use of denial, be it conscious or subconscious in dealing with the trauma of the experience. …for a long time I was just, well, in denial I think, “oh no, I'll be alright, I'll be alright… 6M But when they (thoughts/feelings associated with major PE) come to the surface, well I have puzzles and things which I do to block it out…I don't want to think about it so my puzzles are one way of avoiding thinking about it for me. 1F

    Hypervigilance

    Patients reported increased vigilance and awareness of anxiety of any symptoms they felt could be associated with a recurrent PE. Such awareness was associated with increased anxiety and catastrophising thought processes. In the beginning I was very very very weary, very scared. I would only have to get a sort of sign or niggle in my chest and I would start to panic thinking that it was going to happen again or I'd end up in a heap on the floor 2F It was always on my mind. It made me more conscious of making sure that if I was on my own somewhere people knew…I taught my daughter nannies house number…just in case something did happen. It just makes me angry to think that no-one can tell me I won't have another one and now I have to live my life by this 2F

    Major theme 3: support needs

    All participants described needing a significant degree of support and it was evident that the support needed was ongoing but differed over time. The nature of support required often required clinical and or specialist knowledge, and appeared to be an unmet need, which could only be met by appropriate healthcare professionals.

    Information

    During the initial stages of diagnosis and treatment, participants required considerable information regarding their condition, their prognosis and long-term treatment. Many described their care as focusing on the biomedical with little attention given to support through information giving or psychological care. None of them actually said anything to make me understand, it was just a case of ‘you've had these clots, they've gone to your lungs’, none of the rest of what else could have happened before they got to the lungs registered or how serious it was when it got to there. 5F

    Where information was not freely available, participants would seek answers on the Internet. This could result in accessing upsetting information, which without access to additional support or proved more distressing than helpful. Yeah after looking on the internet I did the whole sitting, crying, rocking thing thinking ‘oh me god’ and then told myself off for looking to be honest because finding out that way with no-one there to kind of go through it with me knocked me for six. M5

    Participants were clear on the degree of information they required: frequently describing the need to understand why this had happened to them and what they should/ should not do from then on to rehabilitate effectively. It causes me quite a lot of concern doing things…and I'm scared of doing them in case it happens again…I just get so annoyed that's that the thing that will stop me, because I worry that if I get a bit out of breath or feel my heart going that I'll end up in a heap on the floor basically…but I wouldn't worry as much if I just knew what was causing it, or someone could tell me how much I can push myself It just annoys me because I just can't achieve what I used to achieve and I just haven't got the answers as to why. Why can't I? What's stopping me? What's making that happen to me? If I had the answers I'd be alright with it. I'd get on with it. 3F When basic information was provided, including realistic outcomes, participants were able to make more sense of their lives and symptoms, describing a more positive rehabilitation. So I asked if he could provide me with some information about what was the likely cause and some information about what I could expect or hope for really in recovering for me which was quite a fortuitous bit of information that I got which encouraged me a bit but it sort of did seem possible that by just keeping on with the blood thinning that these could eventually get re-absorbed and I could get back to sort of normal activity. 4M

    Empathy

    Participants considered themselves to have experienced a narrow escape from death and as described before expressed considerable psychological distress after the event. They did not feel that healthcare professionals fully appreciated the seriousness of their experience and thus did not understand the distress associated with symptoms suggestive of VTE recurrence. But I cant remember thinking that you know, I might have died, that my daughter might not have had her mum, and no one helping to make sure that I understood what was going on, or what was wrong with me, or how this would effect my life. I just remember feeling quite resentful of the medical staff. 2F And I did start to panic then and think well you know if I had a pain in the chest again I could be telling someone what I think it is but would they actually take my word for it kind of thing. And I did actually feel that it wasn't really taken too seriously. I mean the fact that it could of killed me and they had a very blasé approach toward it. 2F

    Access to support

    While there was a significant requirement for information and support from healthcare professionals, some participants also identified the potential benefits of self-help/support groups. The opportunity to meet other people who understood their experiences and associated feelings was considered a positive thing and there was a belief that several unmet needs could be provided by fellow patients with PE. I would have loved, and still would like some sort of group thing or support to be available to help me come to terms with what's happened to me…somewhere where somebody could have explained ‘yeah its normal to feel like that’ etcetera, you know like maybe other people who had been through the same thing. I don't think I would of felt so on my own then…Just to have this level of conversation with somebody back then would have helped massively. To help me process it all through, because it was very ‘off you go’ and that was that. 5M

    Discussion

    VTE is a common medical condition, which may cause a spectrum of physical symptoms. In its most severe form, major symptomatic pulmonary emboli may lead to cardiovascular compromise and even death. While the long-term complications such as PTS and pulmonary hypertension are well recognised, little has been known about the psychological impact of symptomatic VTE. In our study of previously healthy adults who experienced a symptomatic pulmonary embolus we have identified that the psychological consequences of experiencing symptomatic VTE are considerable. The development of VTE is considered a life-changing event with some patients feeling a loss of identity and role in life. A profound and ongoing collection of symptoms suggestive of the development of PTSD appears to be more of a concern. This is the first time that PTSD has been identified as a consequence of VTE. To some extent these findings should not come as a surprise since features that contribute to the development of PTSD are common in patients with VTE; patients of previous good health experience a traumatic life-threatening event and face a future of uncertainty regarding recurrence. However, these findings raise the possibility that as healthcare professionals we are failing to recognise the psychological needs of our patients.

    There are several limitations to this study: the number of participants is small and although the numbers are appropriate for such qualitative methodology, a larger study is clearly needed to identify the true prevalence of PTSD using a validated screening tool. In particular it is not possible to identify whether PTSD may be more prevalent in certain subgroups of patients with PE. Within the group sampled the majority were younger than 45 years and it is possible that the greater degree of psychological distress is seen in younger patients with less illness experience. Likewise PTSD may be more prevalent in those without obvious precipitating cause of VTE since they will live with ongoing uncertainty regarding recurrence. The long-term treatment plan may also play a role and it would be interesting to see whether PTSD is more likely to develop in those with ongoing reminders of their illness such as long-term anticoagulation.

    There is a possibility of selection bias since all participants interviewed had required admission to hospital for their symptomatic PE and as such were likely to be those with more severe symptoms and thus a more traumatic experience. While the likelihood of bias is acknowledged, it should not invalidate the findings in the context of those with the most significant VTE episodes. It would be presumptive to assume that all patients with VTE experienced PTSD in the same way that one acknowledges that PTSD occurs in some but not all myocardial infarction patients. It does, however, highlight that of those developing VTE, a subgroup may experience significant psychological sequelae and it would make clinical sense to identify those at greatest risk and arrange appropriate support. At present, it is not possible to identify whether the development of PTSD is directly related to the VTE experience or whether there are particular premorbid characteristics that predispose people. It is of interest to note that participants felt they received limited information and would have liked more opportunities to understand their condition from an appropriately trained professional rather than seek information themselves on the Internet.

    Finally, this study highlights several areas of opportunity for healthcare professionals to deliver support to patients post VTE be it through information giving, empathy or identifying psychological distress early on. It is possible that early intervention may reduce the development of long-term psychological distress and the ongoing challenges it brings.

    SN affirms that the manuscript is an honest, accurate and transparent account of the study being reported; that no important aspects of the study have been omitted and that any discrepancies from the study as planned (and, if relevant, registered) have been explained.

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    Footnotes

    • Contributors SN, PB and SL conceived the study. RL and JW undertook interviews. JW, RL, PB and SN undertook analysis of data. All authors contributed to the final version of the manuscript.

    • Funding This research received no specific grant from any funding agency in the public, commercial or not-for-profit sectors.

    • Competing interests None.

    • Ethics approval Ethical approval was obtained through the National Health Service (NHS) South Wales Research Ethics Committee.

    • Provenance and peer review Not commissioned; externally peer reviewed.

    • Data sharing statement No additional data are available.