2.3.1 Stress and Trauma-Related Disorders

In terms of mental health the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) has specifically recognised trauma- and stressor-related disorders in their own specific category. The DSM-5 offers three main stress response diagnoses in adults (PTSD, acute stress disorder and adjustment disorder) and two in children (reactive attachment and disinhibited social engagement disorders) that are a reaction to specific triggering events (Wakefield, Reference Wakefield2013). PTSD is without doubt the most widely known health condition arising from trauma. It is a diagnosable mental disorder, popularised in literature and film (e.g., to critical acclaim in Born on the Fourth of July). Indeed, the criteria for diagnosis are only met if the symptoms experienced as a result of trauma are severe and prolonged enough to interfere with a person’s social and occupational functioning.

The 1980 edition of the DSM (3) categorised PTSD as a mental PTSD (Spitzer et al., Reference Spitzer, First and Wakefield2007). Though first classified as an anxiety disorder, it has subsequently been reclassified as a ‘trauma and stressor-related disorder’ in DSM-5 (APA, 2013). It is clear that the emotions involved in PTSD are not by any means restricted to fear, helplessness and horror, or to what was actually experienced at the time of the trauma. Although anxiety- or fear-based symptoms are experienced in individuals with trauma- or stressor-related disorders, they are not the primary symptoms. Indeed, people affected by trauma- or stressor-related disorders typically report a state of unease (dysphoria), numbness or inability to feel pleasure (anhedonia) and disconnection from their own thoughts, feelings and experiences (dissociation). Externalising symptoms such as aggression and anger are also reported. The poet Emily Dickinson articulates this constellation of feelings in her poem that appears as the epigraph to this chapter. Her unease is represented by the ‘treading – treading’ and the ‘beating – beating’ – until she thought her ‘mind was going numb’. There is dissociation evident in the poem’s conceit of a funeral occurring in her brain, but equally dissociation is very clearly referred to where the poet’s voice is separated even from humanity ‘Being, but an Ear / And I, and Silence, some strange Race’. In many regards this poem, though usually interpreted as one describing a descent into insanity, speaks to the toll that trauma can take. It removes much of the joy from life.

The symptoms of PTSD that people experience are demonstrably linked to culture (Smelser, Reference Smelser2004). The DSM outlines symptoms of PTSD in pre-defined clusters or factors. The exact number of symptom clusters is debated, and the pattern of symptoms across anger, dissociation, anhedonia and dysphoria varies (for a review, see Armour et al., Reference Armour, Contractor, Shea, Elhai and Pietrzak2016). Emily Dickinson wrote her poem in the nineteenth century; it was first published in 1896 but was, as most scholars agree, likely to have been written in 1861 (Perriman, Reference Perriman2009). Dickinson was born into a prominent family in Amherst, Massachusetts. She lived a very isolated and solitary life. She never married, which, given the norms of the time, restricted her socially. Historical commentators on Dickinson have suggested that her early life was beset by traumatic abuse including incest and later bereavement (Perriman, Reference Perriman2009). Expression of anger or aggression, particularly by women of her class, would have been a culturally inappropriate response, and thus abuse of the type she suffered was rarely acknowledged or discussed. This may explain why anger symptoms don’t make an explicit appearance in her poem. However, even artists, and most especially women from previous eras, worked their realities and rebelliousness into their works to avoid cultural costs of speaking out (Jaspar, Reference Jasper2008). And so in this way we can see the poem itself allows her to speak out. It alludes to – ‘and then a plank in reason, broke’ – and is symptomatic of anger, a key externalising symptom of post-traumatic stress.

In total, the DSM-5 argues that there are eight necessary criteria for a PTSD diagnosis. The first is the experience of a traumatic event (criterion A). The second set of criteria relate to the symptom expression across four clusters (Bisson et al., Reference Bisson, Cosgrove, Lewis and Roberts2015). These include, as already mentioned, persistent negative alterations in cognitions and mood associated with the traumatic event (e.g., anger, guilt, difficulty concentrating), intrusion symptoms (e.g., flashbacks, nightmares), avoidance of trauma reminders (e.g., avoiding ‘trigger’ situations) and alterations in arousal (e.g., difficulty sleeping). In DSM-5 (APA, 2013) a diagnosis of PTSD is seen to be warranted where there are multiple symptoms across these clusters and they are understood as persistent by a clinician (criterion F) and causing significant functional impairment (criterion G) and which are not attributable to other causes (e.g., the physiological effects of substance use or medication: criterion H).

As alluded to already, there is another school of thought, however, that sees the labelling and classification of PTSD as a disorder as problematic. Some commentators advise that it is better to think of all responses to trauma along a continuum of post-traumatic stress (PTS). Proponents of this view would argue that stress responses can be considered reasonable, normal or, indeed, expected reactions to extreme or distressing events (Summerfield, Reference Summerfield2001). Thinking in this way encourages us to think about symptom severity. And it avoids the labelling of symptomatic individuals as ‘disordered’. This gets around some of the negative feelings associated with a mental health diagnosis. Certainly, when I was diagnosed as depressed it felt like an additional burden. And, sadly, this is the way many people, myself included, continue to experience mental health diagnoses. It is also a reason that people struggle with admitting they need help (Kearns et al., Reference Kearns, Muldoon, Msetfi and Surgenor2015), in the way I did. So, thinking about responses to traumatic experiences as PTS rather than PTSD is thought to minimise barriers to seeking help as well as preventing the pathologising of traumatised people. We move away from a dichotomy between those who do or do not warrant a clinical diagnosis. This approach, rather than labelling people who are distressed by extreme events, turns attention to the social conditions that gave rise to traumatic experiences.

The value of avoiding labelling people is amplified by the fact that trauma exposure is so common throughout the world. More than two-thirds of all respondents in the WMH surveys report experiencing a trauma at some point in their lifetime. Without question, my life experience is the rule rather than the exception. The most common response to extreme and distressing events, including war, political violence, rape and sexual assault, accidents and natural disasters, is resilience to their impact (Agaibi & Wilson, Reference Agaibi and Wilson2005). Many people show some PTS in response to extreme or distressing events, but these responses often are short-lived and/or not so severe that they interfere with social or occupational functioning. So, though there have been very many incidents in my life that could be considered traumatic, for the most part, after a period of distress I managed to move on. This is borne out in the research that we have available. For example, using representative samples it has been shown that whilst 50 per cent of people in Northern Ireland have been exposed to more than one traumatic incident as a consequence of political violence (Schmid & Muldoon, Reference Schmid and Muldoon2015), only one in ten shows symptoms severe enough to warrant a diagnosis of PTSD (Muldoon & Downes, Reference Muldoon and Downes2007). Similarly, cross-national longitudinal representative surveys of Israelis, Palestinians and residents of Northern Ireland indicated that while PTS responses severe enough to warrant a diagnosis of PTSD were more prevalent in these samples than in populations unaffected by political violence, they were still only evident in a minority of the population. So, even amongst those who reported direct and repeated exposure to trauma, 75–80 per cent did not warrant a diagnosis of PTSD (Hirsch-Hoefler et al., Reference Hirsch-Hoefler, Vashdi, Lowe, Muldoon, Hobfoll and Canetti2021). Accordingly, understanding the basis of psychological resilience to trauma is just as important as understanding vulnerability.

That said, we also know that the number of years lost to trauma-related disability is considerable. And though trauma is common, the experience of trauma is not evenly or equally distributed (Muldoon, Reference Muldoon2013; World Health Organization, 2011). Take gender, for example. Tjaden and Thoennes (Reference Tjaden and Thoennes1998) estimate that each year 4.8 million acts of violence are committed against women and 2.9 million acts of violence are committed against men in the United States alone. Not only do these experiences have a profound effect on these individuals; they also affect others, including children exposed to this violence. Estimates are that each year in the United States 17.8 million children are exposed to domestic violence, either as witnesses or as targets (Evans et al., Reference Evans, Davies and DiLillo2008). And we know trauma type matters – both to the risk and to the persistence of mental health symptoms. Exposure to intimate partner sexual violence accounts for nearly 42.7 per cent of PTSD evidenced across the twenty-seven countries that participate in the WMH surveys (Kessler et al., Reference Kessler, Aguilar-Gaxiola, Alonso, Benjet, Bromet, Cardoso and Koenen2017). Being both an intentional act of harm and one that undermines our sense of trust even of those with whom we are closest (see Section 1.4), this type of trauma is particularly pathological.

Though statistics reported from various countries are not directly comparable, the WHO (World Health Organization) offers important insights into PTSD prevalence and patterning. The estimates for lifetime PTSD prevalence range considerably between countries, from a low of 0.3 per cent in China to 6.1 per cent in New Zealand (Kessler et al., Reference Kessler, Aguilar-Gaxiola, Alonso, Chatterji, Lee, Ormel and Wang2009). There appears to be very different consequences of trauma, likely related to people’s capacity and capital to manage traumatic stress across countries. For example, most war survivors live in low- to middle-income countries, and estimates of the impact of war suggest that, globally, the number of adult war survivors living with PTSD is huge (Hoppen & Morina, Reference Hoppen and Morina2019). There were an estimated 1 billion adult survivors of wars fought between 1989 and 2015 alive in 2015, and based on geo-referenced data on armed conflicts a further 450 million children (data from the Uppsala Conflict Data Program, Petterson & Eck, Reference Pettersson and Eck2018; Pettersson & Wallensteen, Reference Pettersson and Wallensteen2015). Using a meta-analytic approach to synthesise available data, Hoppen and Morina (Reference Hoppen and Morina2019) estimated that in 2015 there were approximately 242 million adult war survivors living with PTSD. Of these, about 117 million live with comorbid PTSD and major depression. While approximately one-third of cases recover from PTSD within a year, rapid recovery appears to be least likely amongst people with war-related symptoms (Kessler et al., Reference Kessler, Aguilar-Gaxiola, Alonso, Benjet, Bromet, Cardoso and Koenen2017). Indeed, PTSD symptoms following war-related traumas have the longest median duration, at five years, followed by traumas involving physical or intimate partner sexual violence (with a median of three years).

In summary, psychological responses to trauma vary in degree and can change over time. Even in response to the same event, some people will show resilience and others severe symptoms of PTS. And though there will be other times when people struggle, our responses to traumatic events are often marked by resilience. In some cases, symptoms experienced as a result of trauma are severe enough to interfere with a person’s social and occupational functioning and well-being. A diagnosis of PTSD can then ensue. Consequently, recent research efforts have largely focused on identifying those who are at increased risk of poor mental health outcomes if they are exposed to traumatic experiences (Bomyea et al., Reference Bomyea, Risbrough and Lang2012). As we will see in the next chapters, a significant proportion of this variability is linked to social connections, social status, power and politics. This does not diminish the contribution of work that has explored other dimensions of traumatic responses, but rather highlights how group and social identity processes are integral to both experiences and responses to trauma – and hence that those same processes need to inform the way trauma is understood and managed.

2.3.2 Dual and Diverse Consequences of Trauma Exposure

Though trauma and PTSD have their own category of disorder in the DSM-5, in the real world, the psychological problems that people experience because of traumatic experiences are rarely clear-cut. It is apparent that many people living with PTSD have comorbid problems or dual diagnoses. For example, approximately half of the 250 million people living with war-related PTSD live with comorbid major depression (Kessler et al., Reference Kessler, Aguilar-Gaxiola, Alonso, Benjet, Bromet, Cardoso and Koenen2017). Stewart’s (Reference Stewart1996) important early review of the literature concluded that trauma-exposed individuals with PTSD have a higher risk of alcohol abuse than those without PTSD. Later epidemiological studies showed the same pattern with regard to drug abuse (Reed et al., Reference Reed, Anthony and Breslau2007) and tobacco use (Breslau et al., Reference Breslau, Davis and Schultz2003). It is now estimated that individuals with PTSD are four to five times more likely to have a substance misuse disorder, at some point in their lives, compared with individuals who do not have PTSD (Brady et al., Reference Brady, McCauley and Back2021).

In this way we can see that traumatic experience is linked to both PTS and other related psychological problems. Importantly, people who have comorbid diagnoses tend to have higher health costs. The Australian National Survey of Mental Health included 10,641 people and showed that individuals with substance use disorder and comorbid PTSD have significantly poorer physical and mental health and greater disability than those with substance use disorder alone (Mills et al., Reference Mills, Teesson, Ross and Peters2006). Using data from the US National Health and Resilience in Veterans Study (N = 2,732), Nichter et al. (Reference Nichter, Norman, Haller and Pietrzak2019a) similarly showed that the health burden of PTSD and comorbid depression was far greater than one of these diagnoses alone. Further, comorbid depression and PTSD were associated with a three times greater likelihood of disability than depression alone and was also associated with a diagnosis of heart disease and cardiovascular risk. Indeed, the evidence is that dual diagnoses are linked to disability (Campbell et al., Reference Campbell, Felker, Liu, Yano, Kirchner, Chan and Chaney2007), health care utilisation (Chan et al., Reference Chan, Cheadle, Reiber, Unützer and Chaney2009), suicidality (Cougle et al., Reference Cougle, Resnick and Kilpatrick2009) and poorer quality of life (Nichter et al., Reference Nichter, Norman, Haller and Pietrzak2019b). The coincidence of PTSD and depression, and PTSD and substance misuse in this way imposes a greater cost on people’s mental health and well-being than either condition alone (Flory & Yehuda, Reference Flory and Yehuda2022).

There is a second way in which the divergent consequences of traumatic experience need to be considered. PTSD is unique in terms of mental health diagnoses as it stipulates its own causation. However, there are other disorders where traumatic experiences and adversity are seen and theorised to be relevant (Broeman, Reference Broerman2020). Childhood trauma, for example, is an important risk factor for the development of borderline personality disorder (BPD; Ball & Links, Reference Ball and Links2009). BPD was postulated originally to be a disorder inherent in people’s character; now it is increasingly seen to arise from the problematic impact of childhood trauma on interpersonal relations. Typically, someone with BPD has problems in interpersonal relations. This has all sorts of costs for those affected in terms of their ability to engage and integrate in social, health, educational and occupational settings. And it can give rise to further health and well-being costs. BPD, then, though not often thought of as a trauma- or stressor-related disorder, arises from traumatic experiences and can have very high personal and socioeconomic costs (Luyten et al., Reference Luyten, Campbell and Fonagy2020).

Taken together, this work tells us that the mental health implications of traumatic experiences are not clear-cut. People can have more than one set of symptoms and even more than one diagnosis. These can include depression and substance misuse (e.g., alcohol and drugs). People who experience trauma early in life may develop a pattern of behaving that means that they are characterised as having a personality disorder. Reliance on substances such as drugs, alcohol and cigarettes can become problematic and affect physical health outcomes. Reliance on these substances is sometimes a habit that traumatised people have developed to manage their own distress – often referred to as self-medication. Looking back, I can see these patterns in my own mis(use) of alcohol and cigarettes over the years. Relapse is common during times of distress or when further trauma is encountered. And it can be very difficult for people to kick these habits whilst they remain distressed. Understanding the varied and sometimes self-defeating ways in which people respond to trauma has given rise to calls for trauma-informed care (Racine et al., Reference Racine, Killam and Madigan2020). This approach shifts the focus in health, education and social care settings. Rather than seeing traumatised people as problematic, it acknowledges the wide-ranging impact of trauma in the hope of identifying potentially adaptative practices and pathways (Muskett, Reference Muskett2014).

2.4.1 Physiological Pathway

We turn first to the physiological responses to stress and trauma. Physiological arousal in response to short-term (acute) stress is generally indicated by increased blood pressure, cardiac output and alterations in cortisol levels (Heinrichs et al., Reference Heinrichs, Baumgartner, Kirschbaum and Ehlert2003). In laboratory settings, it is reasonably easy to stress people with simple cognitive or social stressors and observe their blood pressure and heart rate increase in response to these stressors. These can be considered short-term responses to stress and are most often driven by adrenaline. Adrenaline also gives rise to increased cortisol production. Cortisol functions to convert energy stored in the body into glucose so that it is ready for use by the body. This facilitates access to energy resources to sustain the increased requirements of our increased heart rate and blood pressure during times of stress. Indeed, these physiological responses to stress are necessary for our bodies to cope with stress. This pattern of arousal can be considered preparation for ‘fight or flight’ as it were. When these responses to stress are large or long-lasting, we see negative effects on our health (Lovallo, Reference Lovallo2015).

Indeed, physiological responses to stress have been an area of serious research effort over the last forty years. It has given rise to a very influential idea in health psychology: the cardiovascular reactivity hypothesis (Obrist, Reference Obrist2012). Cardiovascular reactivity (CVR) measures the physiological changes, from baseline, in response to a stressor. Research shows that exaggerated or prolonged cardiovascular (i.e., blood pressure and heart rate) responses to stress are associated with increased risk of cardiovascular disease (CVD) development (Chida & Steptoe, Reference Chida and Steptoe2009). Generally, the more prominent and intense a stimulus or stressor is, the greater the disease risk. Cardiovascular reactivity offers a way of understanding how acute stress might affect our physical health.

The cumulative burden of repeated or chronic stress and the associated cost of cardiovascular reactivity in response to chronic stress is an important consideration. People and groups exposed to repeated trauma experience longer-term or sustained physiological responses (Gallagher et al., Reference Gallagher, Muldoon and Bennett2021). Allostatic load is a useful concept representing the cumulative burden of chronic stress on the body’s multiple physiological systems (e.g., metabolic, immune and endocrine) as people attempt to adapt to life’s many demands (McEwen and Stellar, Reference McEwen and Stellar1993). Allostatic load has been shown to be associated with CVD morbidity and mortality (Rumsfeld et al., Reference Rumsfeld, MaWhinney, McCarthy, Shroyer, VillaNueva, O’Brien, Moritz, Henderson, Grover, Sethi and Hammermeister1999; Zhang et al., Reference Zhang, Pozuelo, Brennan, Hoar and Hoogwerf2010). This cumulative burden of stress and trauma is profoundly linked to later health outcomes.

Whilst much research has found that individuals who display exaggerated responses to acute psychological stress are at a greater risk of future hypertension, atherosclerosis and cardiovascular mortality (Carroll et al., Reference Carroll, Ginty, Der, Hunt, Benzeval and Phillips2012; Gerin et al., Reference Gerin, Pickering, Glynn, Christenfeld, Schwartz, Carroll and Davidson2000), a failure to mount a sufficient response is also related to poorer health (Keogh et al., Reference Keogh, Howard and Gallagher2022; Phillips et al., Reference Phillips, Ginty and Hughes2013). These types of responses are sometimes called ‘blunted’. The idea of a blunted response is in line with allostatic load theory, which highlights that ongoing stress and trauma leads to ‘wear and tear’ on the body (Glei et al., Reference Glei, Goldman, Chuang and Weinstein2007; Guidi et al., Reference Guidi, Lucente, Sonino and Fava2021). Effectively, chronic stress and trauma reduce our ability to mount an adequate response in the face of ongoing stress. In our own research we have found that childhood trauma is linked to blunted reactivity, and this was most apparent in people with less social integration (McMahon et al., Reference McMahon, Griffin, Borinca, Bradshaw, Ryan and Muldoon2022). Blunted cardiac reactivity is also related to increased depressive symptoms, addiction, obesity and poorer self-reported health and well-being (Keogh et al., Reference Keogh, Howard, Gallagher and Ginty2023; Phillips, Reference Phillips2011).

The physiological responses to stress and trauma do not just alter cardiac responses, however. Neuroendocrine reactivity, and in particular cortisol in response to stress, is a second key mechanism. Exaggerated neuroendocrine responses occur in situations of chronic or extreme stress, which can increase disease risk and also impact cognitive functioning. Cortisol acts as a biological intermediary between trauma and health (Cohen et al., Reference Cohen, Kessler and Gordon1997). Increased cortisol activity is displayed in response to laboratory stress and daily life stress (Gallagher et al., Reference Gallagher, Sumner, Muldoon, Creaven and Hannigan2016; Keitel et al., Reference Keitel, Ringleb, Schwartges, Weik, Picker, Stockhorst and Deinzer2011) and in response to trauma such as child abuse (Chavustra & Cloitre, Reference Charuvastra and Cloitre2008). Cortisol, as well as making energy available during times of stress, has an immune-suppressing effect. So, though cortisol can be important in facilitating increased energy demands, over time increased cortisol interferes with the body’s immune function and our ability to fight disease (Irwin, Reference Irwin2008; Segerstrom and Miller, Reference Segerstrom and Miller2004).

This alteration of immune function has serious implications for people’s health over the short and long term. Originally, Janice Kiecolt-Glaser and Ronald Glaser (Reference Kiecolt-Glaser and Glaser1992) set out to consider the impact of spousal bereavement on immune function. They had noted the tendency, as was the case for my own parents, for cohabiting spouses to die within a year of each other. Their work led to the development of a field known as psychoneuroimmunology. Amongst other developments, this field has now identified links between the psychological and physiological features of cancer risk. The persistent activation of the hypothalamic-pituitary-adrenal axis during chronic stress is believed to impair immune response and contribute to the development and progression of cancer. Molecular immunological factors during the consecutive stages of the multistep immune reactions have been shown to depend on the type, chronicity and intensity of the stressor (Reiche et al., Reference Reiche, Nunes and Morimoto2004). Altered immune function is similarly linked to the maintenance and progression of other diseases. For example, in the short term, antibody responses to vaccination are poorer in those with greater experience of stress and trauma (Burns et al., Reference Burns, Carroll, Ring and Drayson2003; Burns and Gallagher, Reference Burns and Gallagher2010; Pedersen et al., Reference Pedersen, Zachariae and Bovbjerg2009; Phillips, Reference Phillips2011; Whittaker, Reference Whittaker2018). Again, this evidence is consistent with the idea that stress and trauma are a type of wear and tear on the body, and over time this (allostatic) load alters people’s functional adaption to stress.

2.4.2 The Behavioural Pathway

Any physiological effects of traumatic experience on health are likely amplified by the behavioural pathway that links stress, trauma and health. Behaviours that are linked to health are known as health behaviours. For the most part, this crucial role of behaviour in shaping morbidity and mortality has become widely accepted across medicine and epidemiology over the last three decades. Behavioural immunogens are behaviours that support health such as having a balanced diet, exercising regularly and practicing safe sex. Behavioural pathogens are behaviours that damage health such as smoking, substance misuse or poor sleep patterns. Stress and trauma appear to alter both habitual (i.e., regular, day-to-day) and non-habitual health behaviours (Sergestron & O’Connor, Reference Segerstrom and O’Connor2012).

The idea that stress is linked to health behaviours is a popular one. A quick click on the internet displays plenty of information on the adverse effects of stress for overeating, smoking, and alcohol consumption. And science generally backs up the popular notion that stress can change health behaviours. Stress is associated with higher fat diets (Laitinen et al., Reference Laitinen, Ek and Sovio2002; Ng & Jeffery, Reference Ng and Jeffery2003) and greater fast food consumption (Steptoe et al., Reference Steptoe, Lipsey and Wardle1998), higher levels of smoking and reduced probability of smoking cessation (Steptoe et al., Reference Steptoe, Wardle, Pollard, Canaan and Davies1996), increased alcohol consumption (Steptoe et al., Reference Steptoe, Lipsey and Wardle1998) and lower levels of physical activity (Kivelä et al., Reference Kivelä, Pahkala and Laippala1991; Ng & Jeffery, Reference Ng and Jeffery2003; Steptoe et al., Reference Steptoe, Lipsey and Wardle1998).

Health behaviours are also strongly intertwined with mental health (Parletta et al., Reference Parletta, Aljeesh and Baune2016). Existing research testifies to the reciprocal nature of interactions between physical well-being, chronic disease and mortality. However, it is also becoming clear that health behaviours have an impact on mental health. For example, in one important study, the people adopting no healthy behaviours had 2.7 times more depressive symptoms compared with those adopting four healthy behaviours (Harrington et al., Reference Harrington, Perry, Lutomski, Fitzgerald, Shiely, McGee and Shelley2010). In another large-scale study, physical activity, alcohol consumption, smoking, body mass index and regularity of social interaction were all associated with specific mental health outcomes (i.e., depression, anxiety and stress) (Velten et al., Reference Velten, Lavallee, Scholten, Meyer, Zhang, Schneider and Margraf2014). Physical activity has been identified as an important protective factor in reducing the risk of developing depression (Mammen & Faulkner, Reference Mammen and Faulkner2013). So, my engagement with running as an important way to manage my mental health is nicely backed up by science.

While numerous studies consider the relationship between stress and specific health behaviours, much of this research is based on clinical samples or conducted in laboratory settings that rely on simulated stressors (Umberson et al., Reference Umberson, Liu and Reczek2008). Community samples can link naturally occurring stressors and health behaviours in the general population. For the most part, these are cross-sectional studies rather than longitudinal ones. They offer a snapshot of the relationship between stress and health at one point in time. Studies of this nature present the perennial ‘chicken and egg’ question: Which came first? Does stress cause poor health behaviour, or poor health behaviour cause stress? Longitudinal research is needed to establish the direction of the relationship between severe trauma and stress and health behaviour over a person’s lifetime. For now, available evidence seems to suggest that chronic stress and the disadvantages that co-exist with traumatic experiences tend to make the establishment of predictable and healthy lifestyle practices difficult. Indeed, disadvantaged circumstances would appear to be a type of stress in and of itself (Ryan et al., Reference Ryan, Muldoon, Gallagher and Jetten2021; Ryan et al., Reference Ryan, Gallagher, Jetten and Muldoon2022).

2.4.3 Personal Pathways to Health?

So, if I return to the idea that my own life has been charmed, certainly it would seem that although I have a relatively sedentary job, the predictability of the hours that I work has allowed me to develop healthy habits. Cortisol tends to peak in the morning, so running before a day’s work puts this waking cortisol to good use. It also leaves me with a small sense of accomplishment as I face the day. Of course, running five kilometres before a day’s work might be a very different proposition were I about to face a day’s work on my feet, a prospect often associated with low-paid work. Nor would it be possible to leave my children home alone early in the morning to run were I a single mother. Engagement in regular exercise also requires time, something that is often in short supply for those caring for children, elders or disabled relatives. Unsurprisingly, there have been times in my life when I have struggled to find that time – when my parents were ill, when my husband was ill, when my children were ill. So, though exercise is often presented as an activity we ‘choose’, in reality, regular running or a pastime of any sort is much more of a luxury than a ‘choice’. And it is when we need to be maintaining our destressing habits most that we tend to have the least capacity to engage. In this way we can see that whilst individual action is relevant to health behaviour, it is simplistic to think that people’s health behaviour is all about healthy choices. Social, cultural and political factors shape both stress and health behaviours.

Strong assumptions about the role of individual factors in shaping health behaviour are evident across the literature in health psychology and epidemiology (Muldoon, Liu & McHugh, Reference Muldoon, Liu and McHugh2021). This can lead to scenarios where those affected by both health issues are seen as ‘deserving’ of their ill-health, or culpable as it were. By doing this, we erase the barriers that prevent people from engaging in healthy behaviours. To enact any health behaviour you must be both willing and able. You have to want to run and be able to run. You have to want to get vaccinated and also have access to a vaccine. But I might not feel safe enough to run if I am routinely harassed on the street. I might not be willing to get vaccinated if I have reason to mistrust the government or big pharma. Capacity to act is profoundly related to opportunity, (dis)ability and available resources. Maybe I have no time to run, or have a disability, or simply no shoes to run in. Maybe I can’t get vaccinated due to work rules that do not permit time off for health care, or I have an underlying health condition, or there are no vaccines available where I live. Because we assume people’s health is driven by choice, we are willing to judge and even vilify those who don’t exercise, drink too much or don’t get vaccinated. Sometimes we even damn ourselves for not doing these things. In so doing we obscure the role of social and political forces that drive trauma, health behaviour and disease risk.

This has two important implications for longer-term health. First, traumatic experience and chronic adversity affect people’s lives in ways that affect their ability to access health and social care as well as changing their social and health care usage. Trauma-informed care aims to support engagement with public health and treatment to maximise health outcomes for vulnerable populations and, in particular, those who have lived with chronic stress. This includes offering advice about adherence or health practices that is viable for people. Advice needs to be tailored for each person’s situation. Post-traumatic stress in marginalised and stigmatised groups can be misinterpreted as aggression and hostility, limiting access to services further. So, the potential for misunderstanding is high. However, there remains a duty of care to those with ostensibly self-destructive behaviours in universal health and social care systems. And it is always worth remembering that people sometimes have a good reason for limited trust in statutory services.

The second implication of this approach is the realisation that destructive lifestyles, rather than being a product of poor choices, can be habitual practices borne of chronic stress and trauma. In many regards, debates about the root cause of ill-health, and whether it is as a result of poor lifestyle choices or adverse life circumstances, go to the heart of an important methodological issue. This methodological concern – whether trauma and adversity cause poor mental health and lifestyle practices or whether poor mental health and lifestyle practices cause adversity – is often seen as a highly politicised question. In reality, this is fundamentally a political psychological question: at its heart it asks who is, and isn’t, deserving of care and concern.