Resilience – a key to tackling chronic stress

‍Highlights:

• Chronic stress is ubiquitous in life and requires effective approaches to deal with negative health effects
• Resilience resources are psychological, social, and economic characteristics that help increase our resistance to stressors exposure
• On a personality level, such traits as optimism, cognitive flexibility, and active coping are key features that help to increase resilience
• Social network and social-seeking behavior are also of extreme importance
• A healthy diet, proper amount of sleep, and regular exercise are essential supportive strategies in stressful conditions 

Introduction

Chronic stress detrimentally impacts both physical and mental health, serving as a trigger to multiple diseases and accelerating aging. The question is whether or how it is possible to minimize and eliminate the harmful effects of long-term exposure to the stressors. Many studies show that the damaging impact of stress depends on the perception of stress, which is dependent on many factors – social, personal, and genetic. A deeper understanding of these factors and their influence is the key to successfully cope with chronic stress and recover after it. At the moment, no single “magic pill” strategy exists to eliminate chronic stress, but multiple approaches have demonstrated their efficiency.

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What is allostatic load?

The term allostasis (1) is used to describe a process of biological adaptation. In other words, allostasis can be described as preserving stability through change. It is crucial to maintain homeostasis to meet the requirements of the environment, and like positive stress, allostasis is a necessary process. However, when we speak about toxic stress, a multi-systemic strain of constant readaptation is referred to as allostatic load (AL) (2). Except for physiological effects, AL and chronic stress become synchronized with unhealthy behavior over time, such as poor sleep, unhealthy diet, smoking, and excessive alcohol consumption.

AL can be quantified (3) and originally was evaluated using data from the MacArthur Studies of Successful Aging cohort. A count-based AL index included the following ten biomarkers:

• 12-hour urinary cortisol
• adrenaline
• noradrenaline
• serum dehydroepiandrosterone-sulfate (DHEA-S)
• high-density lipoprotein (HDL) and HDL to total cholesterol ratio
• plasma glycosylated hemoglobin
• aggregate systolic and diastolic blood pressures
• waist-to-hip-ratio. 

The higher the AL score is, the more intense is a chronic stress state. Increased AL (4) is associated with numerous causes – socioeconomic disadvantage, poor social networks, workplace stress, maladaptive personality traits, lifestyle behaviors, genetic polymorphisms, and can have many consequences – mortality, cardiovascular disease, psychiatric symptoms, cognitive decline, physical/mobility limitations, and neurological atrophy.

Vulnerability and resilience

The initial theories behind the effects of toxic stress were based on the ‘bottom-up’ approach, attributing all the changes in the brain and behavior to the neurotoxic effect of glucocorticoids. In the early 2000s, these approaches were complimented by the new studies, showing that some consequences of chronic stress may be contributed to a vulnerability effect. The ‘vulnerability hypothesis’ led to multiple studies assessing the “top-down” effect of personal, familial, and social factors on the dysregulation of stress hormones production (5). 

A majority of people get exposed to traumatic and damaging events in their life. However, it was suggested that only a quarter to a third of them (6) would further meet diagnostic criteria for post-traumatic stress disorder (PTSD). This leads to the conclusion that some factors may render an individual more resistant to stress. A twin study by Gilbertson et al. (7) demonstrated that smaller hippocampal volume can serve as a pre-requisite for developing PTSD. Other studies similarly reported smaller hippocampal volumes prior to depressive episodes in patients (8) and first schizophrenic episodes (9). This suggests that vulnerability to stress lies in the predetermined individual differences.

But are these differences set in stone from birth? Research suggests otherwise, as, contrary to rodents, the human brain is not fully developed at birth. The hippocampus is fully developed by the age of two years, the prefrontal cortex development happens between eight and twenty-five years, and the amygdala continues its development until the late twenties (10). Thus, the factor that coins our initial vulnerability to stress is early life adversity, which encompasses multiple life events ranging from poor parental care to physical abuse. Such events drastically affect brain development (11) and an individual’s stress reactivity later in life.

Research also demonstrates a significant difference between female and male resilience towards chronic stress. Males, on average, present a stronger cortisol reactivity to stress compared to females (12). Interestingly, though multiple biological and evolutionary factors have explained the differences observed in males and females, recent studies suggest that some of the differences may refer rather to gender (as a social construct) and sexual orientation than biological sex (13). For example, research by Juster et al. showed that gay/bisexual men showed lower AL than heterosexual men (14).

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Resilience resources 

But even adverse events in childhood may increase vulnerability in one individual and develop resilience in others. In individuals susceptible to stress, protective mechanisms are overwhelmed by AL and become pathological, while in resilient individuals, the adaptive response is successfully used to maintain homeostasis (15). Though the exact biological mechanism behind resilience is still the subject of intense research, a range of strategies helps to develop and sustain resilience (16). Dunkel Shetter suggested the term resilience resources (17) – one or more predispositions or characteristics at the individual or social level that foster the individual’s ability to maintain functioning despite exposure to stressors. Researchers suggest six categories that can influence one’s resilience (18):

• Personality (empathy, commitment, optimism),
• Ego-related traits (self-esteem, self-confidence, self-control),
• Social Connectivity (social network, available support),
• Cultural Views (religious beliefs, moral beliefs),
• Behavioral Skills (social Skills, response to emotions management),
• Other (socioeconomic status, general health).

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Resilience and individual psychology

Though some events may be imprinted due to stress exposure in childhood, we must remember that our brains are dynamic structures due to neuroplasticity. The field, which is simultaneously the easiest and the hardest to work with, is our personality. High level of intellectual functioning, efficient self-regulation, active coping – all these features are observed in people who are resistant to the impact of extreme stress (19). Interestingly, characteristics such as low self-esteem not only correlate with increased reactivity to stress but also are associated with reduced hippocampal volume (20).

Optimism – expectation for good outcomes has been found to be protective against stress by numerous studies. Optimism not only decreases stress-related arousal (21) but also is associated with quicker recovery times, particularly in older adults (22). Some studies suggest that optimism is a starting point for further successful strategies such as active coping (23). 

Emotional regulation is another drastically important feature. To increase resilience, one can develop an ability to monitor and assess negative thoughts and avoid generalizations and catastrophizing (24). This strategy is known as cognitive reappraisal, cognitive flexibility, or cognitive reframing. Victor Frankl, a famous psychiatrist and a concentration camp survivor, attributed his psychological endurance mainly to this strategy, which he called “meaning finding”.  

Emotional regulation is strongly connected with mindfulness – a moment-to-moment awareness of body activities, feeling, emotions, and sensations. Mindfulness includes multiple techniques derived from a Buddhist meditation practice, and the studies (25,26) show that the awareness approach may counteract the development of depressive or PTSD symptoms.

The most debilitating effect of chronic stress is feeling of helplessness and being out of control. Active coping using behavioral or psychological techniques is the main strategy to overcome helplessness and has been linked to resilience in individuals (27). The main goal during active coping is to change the qualities of a stressor, the stressor itself, or how it is perceived (28). Interestingly, humor has been identified as an important form of active coping. Two main reasons behind that are humor’s ability to alleviate tension and also to attract social support (29).

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Social factors

Personal traits and the ability to self-regulate are of extreme importance, but humans are social animals that require others for a fulfilled life. Existence burdened by chronic stress is no exclusion. Both the presence of social support and the behavior of seeking social support help to resist major adverse life events and toxic stress (30). The inverse is also true – poor social support has been linked to higher vulnerability and incidence of psychiatric disorders. Social-seeking behavior such as altruism has long been associated with resilience (31).

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Lifestyle and diet

Last but not least, one should account for the influence of protective health behavior such as diet, proper amount of sleep, and exercise. Studies have found that such behavior may additionally modify the harmful effects of stress, including telomere attrition (32). Physical exercise has been shown to increase resilience and positively affect psychological well-being, mood, and self-esteem. 

As AL exhibits significant association with multiple diet-related factors (i.e., visceral obesity), maintaining a healthy diet might be an effective strategy to decrease damaging consequences of stressor exposure (33). 

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Recommendations for professionals

If your patient or client experiences chronic stress, any of the abovementioned techniques can be employed to help them accumulate a resilience resource. Depending on the personal history and the circumstances, some techniques might be more beneficial than others. Any possible intervention will not “reverse” the impact of stressful events but rather produce compensatory mechanisms (34). The interventions able to produce such mechanism may be “bottom-up” (influencing CNS activity) through pharmaceutical influence or “top-down”, including programs that promote social support and physical activity and psychotherapeutic interventions (i.e., cognitive-behavioral therapy). Intense techniques are not recommended to people whose resilience resources are already depleted. Depending on the state of your client, they might need additional help from a psychotherapist, nutritionist, or health coach.

Conclusions 

Personal traits, social integration, support, maintaining healthy activity levels and diet are all techniques that may help to tackle chronic stress. In cases when a person is not able to control these changes themselves, there is a range of effective psychotherapeutic and pharmaceutical interventions. And though chronic stress is, in many cases, inevitable, developing resilience is drastically important to maintain and improve both quality of life and health. Developing resilience is the main skill that allows to successfully manage stress, thus positively influencing health and promoting longevity.

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This article is the second part of the 2-part article. If you would like to know more about mechanisms behind chronic stress, please, read the article “Slow killer: how chronic stress impairs our ability to strive and live longer”.

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