Abstract

Based on the importance of the stress phenomenon, this research sought to evaluate the relationship between stress, coping strategies, negative life events and biological markers, based on the Transactional Stress Model. A general hypothesis of mediation was formulated: coping strategies would mediate the relationship between negative life events and biological markers. The sample consisted of 96 users of a biomedical school laboratory, in which 77.78% were female. Participants answered the Brief COPE questionnaire, as well as a questionnaire on negative life events. Laboratory tests were collected shortly after the application of the questionnaires. Mediations were found between Venting, Red Blood Cells and Hemoglobin. The research aimed to contribute to the knowledge in the field of stress and coping, as well as to serve as a possible empirical study of the Transactional Stress model.

Keywords:
Coping; negative life events; Stress Transactional Model; Stress

Resumo

Dada a importância do fenômeno do estresse, esta pesquisa procurou avaliar a relação entre estresse, estratégias de enfrentamento, eventos negativos na vida e marcadores biológicos baseados no modelo transacional de estresse. A hipótese geral de mediação é que as estratégias de enfrentamento seriam mediadoras à relação entre eventos negativos na vida e os marcadores biológicos. A amostra consistiu de 96 usuários de um laboratório escola em que 77,78% eram mulheres. Participantes responderam ao questionário Brief-COPE, assim como o questionário de eventos negativos na vida. Os testes laboratoriais foram coletados logo após a aplicação dos questionários. As mediações foram encontradas entre auto-distração células vermelhas e hemoglobina. A pesquisa buscou contribuir com o conhecimento na área de estresse e estratégias de enfrentamento, assim como servir como estudo empírico do Modelo Transacional de Estresse.

Palavras-chave:
Estratégias de enfrentamento; eventos negativos; Modelo Transacional do Estresse; Estresse

Considered by the World Health Organization as the epidemic of the 21st century, reaching 90% of the population, stress is one of the most interesting constructs nowadays (Fink, 2016Fink G. (2016). Stress, Definitions, Mechanisms, and Effects Outlined: Lessons from Anxiety. Em Fink G. (ed.), Stress: Concepts, Cognition, Emotion, and Behavior, Volume 1 of the Handbook of Stress Series. (3-11). Elsevier Inc.). Its importance is so great that it is characterized as an object of study from biological sciences to social sciences. The present research is part of a series of investigations on the subject of stress, and aims to evaluate the relationship between stress, negative life events, coping strategies and biological markers in an exploratory way.

Stress

Although it is a phenomenon already experienced by everyone at least once, stress is difficult to be defined. Hans Selye, known as the Father of Stress, states that "Everyone knows what stress is, but no one really knows" (Selye, 1976Selye, H. (1976). The Stress of Life. McGraw Hill.). This initial definition describes stress as a non-specific body response to any demand, but the concept was modified over the years of research, and a variety of new interpretations emerged (Fink, 2016Fink G. (2016). Stress, Definitions, Mechanisms, and Effects Outlined: Lessons from Anxiety. Em Fink G. (ed.), Stress: Concepts, Cognition, Emotion, and Behavior, Volume 1 of the Handbook of Stress Series. (3-11). Elsevier Inc., McCarty, 2016McCarty, R. (2016). The Alarm Phase and the General Adaptation Syndrome: Two Aspects of Selye’s Inconsistent Legacy. Em Fink G. (ed.), Stress: Concepts, Cognition, Emotion, and Behavior, Volume 1 of the Handbook of Stress Series. (13-20). Elsevier Inc.). Nevertheless, it is important to note that the understanding of stress varies according to the perspective under which it is analyzed.

There are distinct approaches to the field of stress research: the Stimulus concept, the Response concept, the Transactional and the Discrepancy approach (Sonnentag & Frese, 2003Sonnentag, S., & Frese, M. (2013). Stress in Organizations. In B. Weiner , N. W. Schmitt , & S. Highhouse (Eds.), Handbook of psychology: Industrial and Organizational Psychology (Vol. 12, 2, pp. 560-592). John Wiley & Sons.). The first focuses on situational conditions or events. In other words, the stimuli are stressful. Although this approach was criticized, many researchers agree that there are some stimuli that evoke strain in most individuals (Sonnentag & Frese, 2003Sonnentag, S., & Frese, M. (2013). Stress in Organizations. In B. Weiner , N. W. Schmitt , & S. Highhouse (Eds.), Handbook of psychology: Industrial and Organizational Psychology (Vol. 12, 2, pp. 560-592). John Wiley & Sons.). The second, defended by Selye, states that stress exists if an individual shows a specific reaction pattern. This approach also received critics because it does not take into account that different people present different types of coping strategies that can alter the stress response. The other two approaches, Transactional and Discrepancy, take into account that the interaction between individual and stress event is what defines stress. The Transactional approach, from Lazarus and Folkman, suggests that the interaction between the individual’s perceptions, interpretation and coping strategies plays a role (Krohne, 2001Krohne, H. W. (2001). Stress and Coping Theories. International Encyclopedia of the Social & Behavioral Sciences, 15163-15170. https://doi.org/10.1016/B0-08-043076-7/03817-1
https://doi.org/10.1016/B0-08-043076-7/0... ; Lazarus, 1993aLazarus, R. S. (1993a). Coping theory and research: past, present, and future. Psychosomatic medicine,55(3), 234-247. https://doi.org/10.1097/00006842-199305000-00002
https://doi.org/10.1097/00006842-1993050... ,bLazarus, R. S. (1993b). From psychological stress to the emotions: A history of changing outlooks.Annual review of psychology,44(1), 1-22. https://doi.org/10.1146/annurev.ps.44.020193.000245
https://doi.org/10.1146/annurev.ps.44.02... ), and the Discrepancy concept describes stress as a distance between desires and what is provided by the environment (Sonnentag & Frese, 2003Sonnentag, S., & Frese, M. (2013). Stress in Organizations. In B. Weiner , N. W. Schmitt , & S. Highhouse (Eds.), Handbook of psychology: Industrial and Organizational Psychology (Vol. 12, 2, pp. 560-592). John Wiley & Sons.).

These interpretations open possibilities for the understanding of stress as a phenomenon, not only negative, but also of positive valence. Positive stress would be the type that prepares the individual to face potential challenges, while negative stress is divided into two categories (McEwen, 2016McEwen, B.S. (2016). Central Role of the Brain in Stress and Adaptation: Allostasis, Biological Embedding, and Cumulative Change. Em Fink G. (ed.), Stress: Concepts, Cognition, Emotion, and Behavior, Volume 1 of the Handbook of Stress Series. (40-56). Elsevier Inc.). The first represents tolerable stress, which refers to a daily situation to which the individual can adapt and/or face due to enough internal and/or external support. The second category is toxic stress, in which the individual experiences situations for which he or she does not have the necessary support, resulting in adverse physical and mental consequences (McEwen, 2016McEwen, B.S. (2016). Central Role of the Brain in Stress and Adaptation: Allostasis, Biological Embedding, and Cumulative Change. Em Fink G. (ed.), Stress: Concepts, Cognition, Emotion, and Behavior, Volume 1 of the Handbook of Stress Series. (40-56). Elsevier Inc.).

These consequences can be seen in the well documented effects stress has on the cardiac system (Rogers, 2016Rogers, H. L. (2016). Heart disease and the stress hypothesis in the mid-twentieth century: a historical review. Psicologia-Reflexao E Critica, 29(47), 1-8. https://doi.org/10.1186/s41155-016-0053-5
https://doi.org/10.1186/s41155-016-0053-... ), immune functioning, the excretion of hormones (Costa et al., 2016Costa, M. A., Gadea, M., Hidalgo, V., Pérez, V., & Sanjuán, J. (2016). An effective Neurofeedback training, with cortisol correlates, in a clinical case of anxiety. Universitas Psychologica, 15(5). https://doi.org/10.11144/Javeriana.upsy15-5.entc
https://doi.org/10.11144/Javeriana.upsy1... ; Martin & Dobbin, 1998Martin, R. A., & Dobbin, J. P. (1988). Sense of Humor, Hassles, and Immunoglobulin A: Evidence for a Stress-Moderating Effect of Humor. The International Journal of Psychiatry in Medicine, 18(2), 93-105. https://doi.org/10.2190/724B-3V06-QC5N-6587
https://doi.org/10.2190/724B-3V06-QC5N-6... ), and its association with affective and behavioral reactions (Sonnentag & Frese, 2003Sonnentag, S., & Frese, M. (2013). Stress in Organizations. In B. Weiner , N. W. Schmitt , & S. Highhouse (Eds.), Handbook of psychology: Industrial and Organizational Psychology (Vol. 12, 2, pp. 560-592). John Wiley & Sons.). However, stress has shown mixed results in relation to some of those variables, depending on the reaction the individual has to it (Pulopulos & Kozusznik, 2018Pulopulos, M. M., & Kozusznik, M. W. (2018). The moderating role of meaning in life in the relationship between perceived stress and diurnal cortisol. Stress, 0(0), 1-8. https://doi.org/10.1080/10253890.2018.1429397
https://doi.org/10.1080/10253890.2018.14... ). As an example, a study by Keller et al. (2012Keller, A., Litzelman, K., Wisk, L. E., Maddox, T., Cheng, E. R., Creswell, P. D., & Witt, W. P. (2012). Does the perception that stress affects health matter? The association with health and mortality.Health Psychology,31(5), 677. https://doi.org/10.1037/a0026743.
https://doi.org/10.1037/a0026743... ) sought to assess the relationship between the amount of stress experienced, the perception that stress affects health and the impact on health and mortality rates. The study had a sample of 30,000 Americans and, by using public records to monitor mortality, concluded that individuals who reported high levels of stress and the perception that stress was detrimental to health had a 43% increase in the risk of death, while those who reported high levels of stress but did not present the belief that stress was harmful had the lowest mortality rate. Another study by Jamieson, Mendes and Nock (2013Jamieson, J. P., Mendes, W. B., & Nock, M. K. (2013). Improving acute stress responses: The power of reappraisal.Current Directions in Psychological Science,22(1), 51-56. https://doi.org/10.1177/0963721412461500
https://doi.org/10.1177/0963721412461500... ) reported that it is possible to rethink the physiological responses from stress as positive, thus avoiding the negative health effects commonly associated with the phenomenon.

These studies go in accordance with what is proposed by the researchers’ choice of approach, the Transactional Model. It was developed by Lazarus and Folkman (1984Lazarus, R. S., & Folkman, S. (1984).Stress, appraisal, and coping. Springer publishing company.) and describes stress as a subjective process involving cognitive evaluation and coping strategies, with empirical support (Pulopulos & Kozusznik, 2018Pulopulos, M. M., & Kozusznik, M. W. (2018). The moderating role of meaning in life in the relationship between perceived stress and diurnal cortisol. Stress, 0(0), 1-8. https://doi.org/10.1080/10253890.2018.1429397
https://doi.org/10.1080/10253890.2018.14... ). In this model, we do not study stress by separating the stimulus from the individual, but from the point of view that there is a transaction in which the individual must constantly adapt to the stressor. These stressors are challenging environmental circumstances to which individuals respond (Hulbert-Williams, Morrison, Wilkinson, & Neal, 2013Hulbert-Williams, N. J., Morrison, V., Wilkinson, C., & Neal, R. D. (2013). Investigating the cognitive precursors of emotional response to cancer stress: Re-testing Lazarus's transactional model.British Journal Of Health Psychology, 18(1), 97-121. https://doi.org/10.1111/j.2044-8287.2012.02082.x
https://doi.org/10.1111/j.2044-8287.2012... , Biggs, Brough, & Drummond, 2016Biggs, A., Brough, P., & Drummond, S. (2016). Lazarus and Folkman's psychological stress and coping theory. In C. L. Cooper & J.C. Quick (eds.), The Wiley handbook of stress and health: A guide to research and practice (pp. 351-364). Nova Jersey: Wiley Blackwell. https://doi.org/10.1002/9781118993811.ch21
https://doi.org/10.1002/9781118993811.ch... , Monroe & Slavish, 2016Monroe, S.M. & Slavich, G.M. (2016). Psychological Stressors: Overview. Em Fink G. (ed.), Stress: Concepts, Cognition, Emotion, and Behavior, Volume 1 of the Handbook of Stress Series. (109-116). Elsevier Inc.).

In the presence of stressors, the individual evaluates their significance and potential threat in order to judge it as stressful, positive, controllable, challenging or irrelevant. This process is known as primary appraisal. The next step is the assessment of the individual's resources to deal with the stressor, called the secondary appraisal. The wide variety of assessments made by individuals in the same environment can be explained by the use of two variables during the transaction: individual aspects such as values, goals and beliefs; as well as external aspects, like demand and resources. After the two appraisals, the individual employs the coping strategy chosen (Erbas, Ceulemans, Kalokerinos, & Houben, 2018Erbas, Y., Ceulemans, E., Kalokerinos, E., & Houben, M. (2018). Why I don’t always know what I’m feeling: The role of stress in within- person fluctuations in emotion differentiation. Journal of Personality and Social Psychology,115(2), 179-191. https://www.researchgate.net/publication/324889378
https://www.researchgate.net/publication... ; Evans & Cohen, 1987Evans, G W, & Cohen, S. (1987). Enviromental Stress. In Stokols, D & Altman, I (Eds.), Handbook of Enironmental Psychology (pp. 571-610). John Wiley & Sons.; Biggs, Brough, & Drummond, 2016Biggs, A., Brough, P., & Drummond, S. (2016). Lazarus and Folkman's psychological stress and coping theory. In C. L. Cooper & J.C. Quick (eds.), The Wiley handbook of stress and health: A guide to research and practice (pp. 351-364). Nova Jersey: Wiley Blackwell. https://doi.org/10.1002/9781118993811.ch21
https://doi.org/10.1002/9781118993811.ch... ).

The main premise of the model is that coping assessments and coping strategies mediate the relationship between stressor and the consequences of stress. Considering it is the perception of the event and how we deal with it that is stressful, not the event itself (Goh & Oei, 2010Goh, Y. W., Sawang, S., & Oei, T. P. (2010). The revised transactional model (RTM) of occupational stress and coping: an improved process approach.The Australasian Journal of Organisational Psychology, 3, 13-20. https://doi.org/10.1375/ajop.3.1.13
https://doi.org/10.1375/ajop.3.1.13... ).Cobb (1976Cobb, S. (1976). Social support as a moderator of life stress. Psychosomatic Medicine, 38(5), 300-314. https://doi.org/10.1097/00006842-197609000-00003
https://doi.org/10.1097/00006842-1976090... ), suggested a moderator effect, but also described the mediator effects of social support in life stress (Pulopulos & Kozusznik, 2018Pulopulos, M. M., & Kozusznik, M. W. (2018). The moderating role of meaning in life in the relationship between perceived stress and diurnal cortisol. Stress, 0(0), 1-8. https://doi.org/10.1080/10253890.2018.1429397
https://doi.org/10.1080/10253890.2018.14... ).

Coping

The resources of the individual to deal with stress involve coping strategies, defined by Lazarus and Folkman (1984Lazarus, R. S., & Folkman, S. (1984).Stress, appraisal, and coping. Springer publishing company.) as constantly changing cognitive and behavioral attempts to deal with a specific internal or external demand to avoid suffering. These strategies can be classified according to the focus. Those who deal directly with the stressor are focused on the problem, while those dealing with the emotions arising from the stressor attempting to alleviate suffering are focused on emotion (Dantzer, 2016Dantzer, R.(2016). Behavior: Overview. Em Fink G. (ed.), Stress: Concepts, Cognition, Emotion, and Behavior, Volume 1 of the Handbook of Stress Series. (57-65). Elsevier Inc.).

One of the factors that influences the strategy used is the personality trait. Lazarus (1993bLazarus, R. S. (1993b). From psychological stress to the emotions: A history of changing outlooks.Annual review of psychology,44(1), 1-22. https://doi.org/10.1146/annurev.ps.44.020193.000245
https://doi.org/10.1146/annurev.ps.44.02... ) states that the traits influence the evaluation process of the stressor and individual resources, thus influencing the strategies used. A study by Ball, Smolin and Shekhar (2002Ball, S., Smolin, J., & Shekhar, A. (2002). A psychobiological approach to personality: examination within anxious outpatients. Journal of Psychiatric Research, 36(2), 97-103. https://doi.org/10.1016/S0022-3956(01)00054-1
https://doi.org/10.1016/S0022-3956(01)00... ) found that optimistic individuals tend to assess the situation more positively and to choose more proactive strategies, whereas more pessimistic individuals tend to underestimate their abilities, assessing the situation negatively, and choosing passive strategies. However, no relation was found between optimistic and pessimistic people in the cortisol levels (Puig-Pérez et al., 2018Puig-Pérez, S., Pulopulos, M. M., Hidalgo, V., & Salvador, A. (2018). Being an optimist or a pessimist and its relationship with morning cortisol release and past life review in healthy older people. Psychology and Health, 33(6), 783-799. https://doi.org/10.1080/08870446.2017.1408807
https://doi.org/10.1080/08870446.2017.14... ), but Martin and Dobbin found a moderated effect by the styles of Humor (1988Martin, R. A., & Dobbin, J. P. (1988). Sense of Humor, Hassles, and Immunoglobulin A: Evidence for a Stress-Moderating Effect of Humor. The International Journal of Psychiatry in Medicine, 18(2), 93-105. https://doi.org/10.2190/724B-3V06-QC5N-6587
https://doi.org/10.2190/724B-3V06-QC5N-6... ).

Lazarus (1993aLazarus, R. S. (1993a). Coping theory and research: past, present, and future. Psychosomatic medicine,55(3), 234-247. https://doi.org/10.1097/00006842-199305000-00002
https://doi.org/10.1097/00006842-1993050... ) also brings the procedural perspective of coping, in which it is understood that strategies can change over the years and are subject to adaptation according to context. Literature suggests that the higher the level of flexibility in the use of coping strategies, the better the level of adaptation of the individual to stressful situations (Cheng, Lau, & Chan, 2014Cheng, C., Lau, H. P. B., & Chan, M. P. S. (2014). Coping flexibility and psychological adjustment to stressful life changes: A meta-analytic review.Psychological bulletin,140(6), 1582. https://doi.org/10.1037/a0037913.
https://doi.org/10.1037/a0037913... ). This suggests we, humans, are dynamic and that individual-environment interactions are of the utmost importance.

Different authors propose different coping strategies because of the multifaceted nature of the phenomenon. This study adopted the strategies proposed by Charles Carver (1997Carver, C. S. (1997). You want to measure coping but your protocol’s too long: Consider the brief cope.International journal of behavioral medicine ,4(1), 92-100. https://doi.org/10.1207/s15327558ijbm0401_6
https://doi.org/10.1207/s15327558ijbm040... ), based on the work of Lazarus and Folkman. The strategies are described in Table 1.

In order to define whether a coping strategy is adaptative or maladaptive, one must analyze the context and function that the strategy has at that particular moment. This definition varies between individuals and depends on short-term and long-term appraisal, but it is important to keep in mind that no strategy is appropriate for all situations. The primary appraisal will determine the nature of the situation, and during the secondary appraisal the best coping strategy will be selected. In the end, based on the result of the use of strategies and new environmental information, a reassessment is made in order to ascertain the success of the process (Biggs, Brough, & Drummond, 2016Biggs, A., Brough, P., & Drummond, S. (2016). Lazarus and Folkman's psychological stress and coping theory. In C. L. Cooper & J.C. Quick (eds.), The Wiley handbook of stress and health: A guide to research and practice (pp. 351-364). Nova Jersey: Wiley Blackwell. https://doi.org/10.1002/9781118993811.ch21
https://doi.org/10.1002/9781118993811.ch... ; Sonnentag & Frese, 2003Sonnentag, S., & Frese, M. (2013). Stress in Organizations. In B. Weiner , N. W. Schmitt , & S. Highhouse (Eds.), Handbook of psychology: Industrial and Organizational Psychology (Vol. 12, 2, pp. 560-592). John Wiley & Sons.).

Most people vary the strategies used to fit the stressor and resources available, which means there is no accurate way to predict what strategies a particular individual will use in the face of a specific problem. The best adapted individuals tend to use different forms of coping for the same stressor, varying according to the stage of the stressor (Erbas et al., 2018Erbas, Y., Ceulemans, E., Kalokerinos, E., & Houben, M. (2018). Why I don’t always know what I’m feeling: The role of stress in within- person fluctuations in emotion differentiation. Journal of Personality and Social Psychology,115(2), 179-191. https://www.researchgate.net/publication/324889378
https://www.researchgate.net/publication... ; Maia, Sendas, Lopes, & Mendes, 2016Maia, Â., Sendas, S., Lopes, R., & Mendes, J. M. (2016). A eficácia das estratégias de coping após um evento traumático: uma revisão sistemática [The Efficiency of Coping Stategies after a Traumatic Event: A Systematic Review Analysis].e-cadernos ces, (25). https://doi.org/10.4000/eces.2058
https://doi.org/10.4000/eces.2058... ; Stephenson, King, & DeLongis, 2016Stephenson, E., King, D.B., & DeLongis, A. (2016). Coping Process. Em Fink, G. (ed.), Stress: Concepts, Cognition, Emotion, and Behavior, Volume 1 of the Handbook of Stress Series. (359-364). Elsevier Inc.). Also, researchers found that, despite sharing similar circumstances (oncologic illness - Al Jadili & Thabet, 2017Al Jadili, M. J., & Thabet, A. A. (2017). The relationship between post-traumatic stress disorder and coping strategies among patients with cancer in Gaza Strip.J Nurs Health Stud, 2, 1. https://doi.org/10.21767/2574-2825.100011
https://doi.org/10.21767/2574-2825.10001... ; Iamin & Zagonel, 2011Iamin, S. R. S., & Zagonel, I. P. S. (2011). Estratégias de enfrentamento (coping) do adolescente com câncer [The coping strategies and the adolescent with cancer].Psicol. argum,29(67), 427-435. https://doi.org/10.7213/rpa.v29i67.20155
https://doi.org/10.7213/rpa.v29i67.20155... ; emergency unit professionals - Ribeiro, Pompeo, Pinto and Ribeiro, 2015Ribeiro, R. M., Pompeo, D. A., Pinto, M. H., & Ribeiro, R. D. C. H. M. (2015). Estratégias de enfrentamento dos enfermeiros em serviço hospitalar de emergência [Coping strategies of nurses in hospital emergency care services].Acta Paulista de Enfermagem,28(3), 216-223. http://dx.doi.org/10.1590/1982-0194201500037
http://dx.doi.org/10.1590/1982-019420150... ), the strategies used by the participants varied according to different contexts and situations. These results show that coping strategies vary between people and they are useful to mitigate health pain and challenges.

Physiological Aspects

In addition to being a cognitive process, stress is physiological. When the brain perceives a stressor, it activates the Autonomic Nervous System (ANS) and the Neuroendocrine System, which elevates the catecholamine levels (adrenaline, noradrenaline and cortisol (Pulopulos et al., 2018Pulopulos, M. M., Hidalgo, V., Puig-Pérez, S., & Salvador, A. (2018). Psychophysiological response to social stressors: Relevance of sex and age. Psicothema, 30(2), 171-176. https://doi.org/10.7334/psicothema2017.200
https://doi.org/10.7334/psicothema2017.2... ) in order to prepare the body to cope with danger. The hormones cause physiological changes, such as increased heart rate, dilated pupils, reduced digestion, elevated blood sugar levels and contraction of the spleen, which upsurges the amount of red blood cells, increasing the supply of oxygen to the tissues. This initial response acts as an alarm (Bauer, 2002Bauer, M. E. (2002). Estresse [Stress].Ciência hoje,30(179), 20-25.). The second system, the hypothalamus-pituitary-adrenal axis (HPA-axis), is regulated by a negative feedback system which is mainly performed by the frontal cortex, amygdala and hippocampus which regulate the return to basal levels (Pulopulos et al., 2018Pulopulos, M. M., Hidalgo, V., Puig-Pérez, S., & Salvador, A. (2018). Psychophysiological response to social stressors: Relevance of sex and age. Psicothema, 30(2), 171-176. https://doi.org/10.7334/psicothema2017.200
https://doi.org/10.7334/psicothema2017.2... ). Those areas of the brain tend to be activated when processing negative rather than positive information and are associated with automatic evaluative processing. There are some evidences that stress hormones have negative effects in the HPA-axis (Ahs et al., 2006Åhs, F., Furmark, T., Michelgård, Å., Långström, B., Appel, L., Wolf, O. T., Kirschbaum, C., & Fredrikson, M. (2006). Hypothalamic Blood Flow Correlates Positively With Stress-Induced Cortisol Levels in Subjects With Social Anxiety Disorder. Psychosomatic Medicine, 68(6), 859-862. https://doi.org/10.1097/01.psy.0000242120.91030.d8
https://doi.org/10.1097/01.psy.000024212... ; Miller, 2013Miller, R., Wankerl, M., Stalder, T., Kirschbaum, C., & Alexander, N. (2013). The serotonin transporter gene-linked polymorphic region (5-HTTLPR) and cortisol stress reactivity: A meta-analysis. Molecular Psychiatry, 18(9), 1018-1024. https://doi.org/10.1038/mp.2012.124
https://doi.org/10.1038/mp.2012.124... ).

The inevitability of facing stress leaves individuals vulnerable to disease, since the reaction to stressors causes immunosuppression, that is, reduction of the defenses of the organism, during the preparation to face the danger. Cardiovascular pathologies, such as arteriosclerosis and strokes; metabolic pathologies, such as insulin-resistant or type 2 diabetes; gastrointestinal pathologies, such as ulcers; reproductive pathologies, such as impotence and miscarriage; among others, are associated with chronic stress (Bauer, 2002Bauer, M. E. (2002). Estresse [Stress].Ciência hoje,30(179), 20-25.; de Kloet, 2016de Kloet, E.R. (2016). Corticosteroid Receptor Balance Hypothesis: Implications for Stress-Adaptation. Em Fink G. (ed.), Stress: Concepts, Cognition, Emotion, and Behavior, Volume 1 of the Handbook of Stress Series. (21-32). Elsevier Inc.).

Because it is the hormone most commonly associated with stress, cortisol, the main glucocorticoid produced and secreted by the adrenal cortex, is the champion in scientific research. The study conducted by Pulopulos and Kozuzsnik (2018Pulopulos, M. M., & Kozusznik, M. W. (2018). The moderating role of meaning in life in the relationship between perceived stress and diurnal cortisol. Stress, 0(0), 1-8. https://doi.org/10.1080/10253890.2018.1429397
https://doi.org/10.1080/10253890.2018.14... ) described a moderated relation between stress and cortisol for individuals with low levels of meaning of life, operationalized as the degree of activities that one is engaged in and was personally valued and important, in other words, that resembled coping strategies in some sense. This is an example of the type of study held comparing biological markers with psychological constructs. Another common laboratory test in the physiological research of psychological aspects is Vitamin D, often associated with depression. An example is the literature review made by Parker, Brotchie and Graham (2017Parker, G. B., Brotchie, H., & Graham, R. K. (2017). Vitamin D and depression.Journal of affective disorders,208, 56-61. https://doi.org/10.1016/j.jad.2016.08.082
https://doi.org/10.1016/j.jad.2016.08.08... ). This review sought to examine whether vitamin D deficiency or insufficiency may be associated with depression and whether supplementation may be an effective treatment. The research concluded that there is growing evidence of the link between the two factors, but there is still a need for more elaborate empirical studies.

However, there are other tests that can be analyzed to assess the biological impact of stress. A systematic literature review by Allen et al. (2017Allen, A. P., Curran, E. A., Duggan, Á., Cryan, J. F., Chorcoráin, A. N., Dinan, T. G.,... & Clarke, G . (2017). A systematic review of the psychobiological burden of informal caregiving for patients with dementia: Focus on cognitive and biological markers of chronic stress. Neuroscience & Biobehavioral Reviews, 73, 123-164. https://doi.org/10.1016/j.neubiorev.2016.12.006
https://doi.org/10.1016/j.neubiorev.2016... ) on the effects of chronic stress in informal caregivers of patients with dementia examined 151 articles that sought to measure the impact of stress through cognitive and/or biological markers. In addition to cortisol, the authors list studies that used glycemia and immune system markers, such as lymphocytes and C-reactive protein, used to detect infections.

C Reactive Protein also appears in other studies, as in the case of Shimano e et al. (2018Shimanoe, C., Hara, M., Nishida, Y., Nanri, H., Otsuka, Y., Horita, M.,...& Tanaka, K. (2018). Coping strategy and social support modify the association between perceived stress and C-reactive protein: a longitudinal study of healthy men and women.Stress, 1-10. http://dx.doi.org/10.1080/10253890.2018.1435638
http://dx.doi.org/10.1080/10253890.2018.... ), who evaluated the impact of social support and coping strategies on the relationship between perceived stress and CRP; or by Rosen et al. (2017Rosen, R. L., Levy-Carrick, N., Reibman, J., Xu, N., Shao, Y., Liu, M.,... & Marmor, M. (2017). Elevated C-reactive protein and posttraumatic stress pathology among survivors of the 9/11 World Trade Center attacks.Journal of psychiatric research,89, 14-21. https://doi.org/10.1016/j.jpsychires.2017.01.007
https://doi.org/10.1016/j.jpsychires.201... ), who evaluated the relationship between CRP and post-traumatic stress in survivors of the Sept. 11 attacks; and O'Donovan et al. (2017O’Donovan, A., Ahmadian, A. J., Neylan, T. C., Pacult, M. A., Edmondson, D., & Cohen, B. E. (2017). Current posttraumatic stress disorder and exaggerated threat sensitivity associated with elevated inflammation in the Mind Your Heart Study.Brain, behavior, and immunity, 6, 198-205. https://doi.org/10.1016/j.bbi.2016.10.014
https://doi.org/10.1016/j.bbi.2016.10.01... ), who evaluated the symptoms of post-traumatic stress in American veterans and reported a positive relationship with CRP.

The present study, unlike previous studies, seeks to outline a more comprehensive picture, not focused on a specific health condition and patient samples. In addition, it will not only focus on cortisol and vitamin D, the two most common tests, making an exploratory collection in order to check other possible relevant relationships. In order to reach that goal, a variety of biological markers, defined as cellular, structural and biochemical components that can delineate cellular and molecular changes in cells, was used, all in the form of blood tests (Capelozzi, 2001Capelozzi, V. L. (2001). Entendendo o papel de marcadores biológicos no câncer de pulmão [Understanding the role of biological markers in lung cancer]. J Pneumol,27(6), 321-28.).

The tests, described in Table 2, were selected because they show a connection with the immune, endocrine, or stress system (Williamson & Snyder, 2015Wallach, J., Williamson, M. A. & Snyder, L.M. (2015). Wallach: interpretação de exames laboratoriais [Interpretation of Laboratory Exams], 10ª ed. Guanabara Koogan). Serotonin, which is also frequent in this line of research, has been eliminated from the list, since its collection requires an prior preparation that does not match the type of collection performed in this study.

Method

Participants

The present study analyzed the responses of 96 participants, of both genders, aged 18 years and over (M = 43.85, SD = 16.20). The inclusion criteria were being over 18 years old, understanding Portuguese, having fasted for 8 hours, and agreeing to participate in the study. The exclusion criteria were having previous diseases (diabetes, cancer or other that could bias the blood markers), and not meeting the inclusion criteria.

All participants were Brazilian, residents of the Federal District and clients of a university laboratory, located in Brasília-DF. This laboratory usually serves the needs of low-income groups but is open to the general population. The total number of respondents was 105, but only 96 answered all the instruments and had all the necessary blood work. Respondents were invited to participate in the survey on a first come, first served basis. The first six patients in line at the laboratory were invited to participate in the study, and in case of no interest or impossibility to meet the criteria, the spot was offered to the following patient. The restriction of six participants was due to the limited number of comfortable seats for the waiting time required for cortisol analysis. The necessary tests for the study were added to the ones already requested by the participant’s doctors at no cost. The purpose of their visit to the laboratory included routine analyses and job admission exams, amongst others. In general, women were more willing to participate, making up 77.78% of the participants (84 females).

With regard to schooling, 17 participants (15.74%) had only elementary education, 57 (52.78%), high school and 19 (17.59%), higher education. The others, corresponding to 13.89% of the participants, were illiterate. In these cases, the researcher read the questionnaire aloud individually so that they could participate.

Instruments

The first instrument used was the Brief Cope Questionnaire (Carver, 1997Carver, C. S. (1997). You want to measure coping but your protocol’s too long: Consider the brief cope.International journal of behavioral medicine ,4(1), 92-100. https://doi.org/10.1207/s15327558ijbm0401_6
https://doi.org/10.1207/s15327558ijbm040... ), adapted to the Portuguese version by Pais-Ribeiro and Rodrigues (2004Pais-Ribeiro, J. L., & Rodrigues, A. P. (2004). Questões acerca do coping: A propósito do estudo de adaptação do Brief Cope [Some questions about coping: the study of the Portuguese adaptation of the Bief Cope].Psicologia, Saúde & Doenças, 5(1), 3-15.) and Marôco et al. (2014Marôco, J. P., Campos, J. A. D. B., Vinagre, M. da G., & Pais-Ribeiro, J. L. (2014). Adaptação Transcultural Brasil-Portugal da Escala de Satisfação com o Suporte Social para Estudantes do Ensino Superior. [Brazil-Portugal Transcultural Adaptation of the Social Support Satisfaction Scale for College Students]. Psicologia: Reflexão e Crítica, 27(2), 247-256. https://doi.org/10.1590/1678-7153.201427205
https://doi.org/10.1590/1678-7153.201427... ). This instrument is composed by 28 items that seek to evaluate the coping strategies most used by the participant, who are instructed to specify how often each strategy is used. The frequency is indicated by a 1 to 4 scale, in which number 1 means never and 4 represents high frequency.

The 28 items denote two statements of each of the following strategies: Active Coping (α .56), Planning (α .40), Positive Reframing (α .60), Acceptance (α .57), Humor (α .79), Religion (α .79), Instrumental Support (α .50), Self-Distraction (α .24), Denial (α .44), Venting (α .84), Behavioral Disengagement (α .75), Self-blame (α .71) and Emotional Support (α .60).

The second instrument used was an adaptation of the Life Events Questionnaire developed by Saranson et al. (1978Sarason, I.G., Johnson, J.H., & Siegel, J.M. (1978). Assessing the impact of life changes: Development of the life experiences survey. Journal of Consulting and Clinical Psychology, 46, 932-946. http://dx.doi.org/10.1037/0022-006X.46.5.932
http://dx.doi.org/10.1037/0022-006X.46.5... ), modified by Norbeck (1984Norbeck, J. S. (1984). Modification of life event questionnaires for use with female respondents.Research in nursing & health, 7(1), 61-71. http://dx.doi.org/10.1002/nur.4770070110
http://dx.doi.org/10.1002/nur.4770070110... ), and adapted for the present research. The original questionnaire consists of 82 items that seek to identify which life events occurred in the previous year, whether positive or negative. Due to the focus of the study, during the translation, the researchers selected only the negative events. In a pre-test with the same group in the university laboratory, the respondents showed difficulties to understand the full scale. It was decided to dichotomize the scale in order to be more understandable for the target demographic. They were asked to indicate any event that had occurred in their life in the previous twelve months. The final result used was the total sum of the negative events reported.

Participants also answered a brief sociodemographic questionnaire with the following demographic data: age, gender, educational level, work, history of disease (thyroid problems, cancer, diabetes and depression), exposure to the sun and physical activity. All the participants signed the terms of informed consent.

The biological markers were evaluated through the analysis of the following laboratory tests: basal plasma cortisol (mandatory rest 20 minutes before the test), thyroid hormone, glycemia, C-reactive protein, complete blood count, serum ferritin, and vitamin D. Samples were withdrawn after the required 8 hour fasting period and stored in vacuum tubes with 4 ml capacity separator gel.

Procedure

Data collection. The project, which is part of a larger study that also analyzes the relationship of psychological constructs with biological markers, was approved by the Ethics Committee, by protocol number 51340715.2.0000.0023, on 05/05/2016.

In order to initiate data collection, the researchers briefly presented the study to the clients present at the lab and all those who agreed to participate in the survey had the laboratory tests offered free of charge, limited to 6 per day due to the comfortable seats available to the respondents.

The collection started daily at 7am. The questionnaires were answered while the clients waited for the blood samples to be taken, after signing the Informed Consent Term. The necessary time to complete the questionnaires varied greatly, taking from 15 minutes to over an hour, depending on the level of instruction of the participant.

The laboratory team, composed of biomedicine students, used ELISA assay methods to analyze the samples and results of the exams, identified only by the protocol number, were made available by the person in charge of the laboratory. They were then inserted into a database, along with the data from the questionnaires.

Data analysis. The bank data were transferred to the SPSS software, where an initial analysis of the correlations was made. From the correlations found, possible triads of mediation were listed, with coping strategies serving as mediators between negative events and biological markers. Alpha’s reliability tests were conducted (and it was between 0.6 and 0.9) to confirm if it was possible to use the instruments. Normality assumptions were tested. Two participants showed non-normal TSH (75.0 and 6.3) and were discarded. Four participants were slightly above 125 in glycemia, and it was decided to keep them because it would not disturb the analysis as they did not have different results in any other dimension. Enter regressions were conducted and Hayes process was used to test the mediation (Model 4). The Sobel test was conducted using software available in Preacher and Leonardelli (2001Preacher, K. J., & Leonardelli, G. J. (2001).Calculation for the Sobel test: An interactive calculation tool for mediation tests[Computer software] http://quantpsy.org/sobel/sobel.htm
http://quantpsy.org/sobel/sobel.htm... ) homepage.

Results

Because of the exploratory nature of the research, the correlations between all the variables were initially analyzed to map the relationships. Only the significant results were described in Table 3. Cortisol, Glycemia and T3 show no significant result with any of the coping strategies.

Keeping the exploratory character, correlations between coping strategies and negative events were also tested. The results are described in Table 4. Self-distraction, Active Coping, Emotional Support, Instrumental Support, Positive Reinterpretation, Planning, Acceptance and Religion show no significant results with negative events.

From the inspection of Tables 3 and 4 and the regressions that confirm the relations, it was decided to test mediation models as a function of the relationship pattern found among the variables, establishing, as a general hypothesis, that coping strategies will serve as mediators in the relationship between negative events and biological markers. The criterion used to select the variables submitted to the mediation test was the existence of a correlation between negative event and coping strategy, and between coping strategy (substance use, venting and self-blame) and biological marker. In order to test the mediations, linear regressions were performed prior to the Sobel test (Preacher & Leonardelli, 2001Preacher, K. J., & Leonardelli, G. J. (2001).Calculation for the Sobel test: An interactive calculation tool for mediation tests[Computer software] http://quantpsy.org/sobel/sobel.htm
http://quantpsy.org/sobel/sobel.htm... ). The results are shown in Figures 1, 2 and 3.

Figure 1 shows a full mediation model test with substance use as a mediator of the negative event and Leukocytes (β _indirect = -.07; Zsobel = .00; p = ns) and CRP (β _indirect = -.08; Zsobel = .43; p = ns) relation. None of the relations were significant.

Figure 2 shows a full mediation model test using venting as a mediator. In the case of Red Blood Cells (RBC) (β _indirect = -.04; Zsobel = -3.63; p <.01) and Hemoglobin (Hb) (β _indirect = -.06; Zsobel = -2.00; p <.05), the effects were significant. However, Hematocrit shows no relation (β _indirect = -.05; Zsobel = .43; p = ns).

Finally, Figure 3, describes the full mediation model test using self-blame as a mediator. In both analyses, the mediations were not significant, neither with Platelets (β _indirect = .05; Zsobel = .03; p < ns) nor with CRP (β _indirect = .09; Zsobel = .66; p = ns).

Figures 1, 2 and 3 illustrate the results found in the mediations tested during data analysis. It is possible to observe the relations between Venting and Hemoglobin and Red Blood Cells, characterized as total mediations.

Discussion

The objective of this study was to evaluate the relationship between coping strategies, negative events and biological markers. No specific hypotheses were formulated due to the exploratory nature of the research. However, a general hypothesis was adopted based on the Transactional Model, the theoretical model of stress that bases the present research, having as main premise the understanding that coping strategies mediate the relationship between the stressor and the physiological reflexes of stress (Goh & Oei, 2010Goh, Y. W., Sawang, S., & Oei, T. P. (2010). The revised transactional model (RTM) of occupational stress and coping: an improved process approach.The Australasian Journal of Organisational Psychology, 3, 13-20. https://doi.org/10.1375/ajop.3.1.13
https://doi.org/10.1375/ajop.3.1.13... ; Pulopulos & Kozusznik, 2018Pulopulos, M. M., & Kozusznik, M. W. (2018). The moderating role of meaning in life in the relationship between perceived stress and diurnal cortisol. Stress, 0(0), 1-8. https://doi.org/10.1080/10253890.2018.1429397
https://doi.org/10.1080/10253890.2018.14... ).

In order to test this general hypothesis of mediation, first, the direct relations between the variables were evaluated. It was possible to verify that relationships identified in previous studies, such as Sladek, Doane, Luecken and Eisenberg (2016Sladek, M. R., Doane, L. D., Luecken, L. J., & Eisenberg, N. (2016). Perceived stress, coping, and cortisol reactivity in daily life: A study of adolescents during the first year of college.Biological psychology,117, 8-15. http://dx.doi.org/10.1016/j.biopsycho.2016.02.003
http://dx.doi.org/10.1016/j.biopsycho.20... ), among stressors, coping strategies and Cortisol were not significant in the present study. One possible explanation is due to the mean that was used for the cortisol test. We collected cortisol in the blood and the best practice is the salivary cortisol. Another possible explanation is related to the negative events. Though there was relation with coping, a stronger relation might be possible if we could ask how much those negative events affected the individual’s life. The original questionnaire is designed in this format, but the respondents, in general, left them blank, either due to embarrassment or not understanding the question.

Some relationships not commonly discussed in the literature, such as the correlation between Venting and Hemoglobin, Hematocrit and Red Blood Cells are significant. Venting decreased the levels of those variables that are responsible for the transport of oxygen throughout the body. In this case, it could be related to symptoms like fatigue. The specifics of how the mechanism of venting could be related to reduced Hb, Ht or RBC are unknown, but they could be explored in future studies. Venting could be considered a maladaptive coping strategy.

CRP also showed a correlation with Self-Blame and substance use, which is notable because it is a biological marker for inflammatory process (Fischbach, 2005Fischbach, F. (2005). Manual de Enfermagem: Exames laboratoriais e Diagnósticos [Nurse's Manual: Laboratory and Diagnostic Tests]. Editora Guanabara Koogan.; Williamson & Snyder, 2015). High levels of CRP have no clear implications apart from indicating an infection. However, those infections could be related to high probability of a heart attacks or cancer, thus, indicating that the body is suffering and needs to be regulated. In this case, we could say that self-blame and substance use are maladaptive coping strategy for this population, but more studies need to be made to test this thesis. Although these indicators result in bad body condition, it is necessary to highlight that, in this study, the participants did not have any especial bad health condition, and also did not present level out of what is considered acceptable or normal.

Another interesting fact is the role played by Religion as a coping strategy, having presented positive relations with Ferritin, Red Blood Cells, Hemogram, T4, Hematocrit and Vitamin D. The results point out a need to investigate relationships beyond those commonly studied in order to analyze possible explanations and promote a better understanding of the physiological effect of stress and coping strategies. Religion, for example, can be interpreted as meditation, hope or social support, and it is not clear if all these possible interpretations perform at the same time or if there is any predominance, questions which will be kept open for future studies.

Another important finding of the present study is the low number of correlations between negative life events and biological markers. Such a result can be considered an indicator that events are not stressful in and of themselves, but that the perception and evaluation of the individual that experiences them dictate the possible effect of the event (Lazarus, 1984Lazarus, R. S., & Folkman, S. (1984).Stress, appraisal, and coping. Springer publishing company.). In other words, even if the events listed in the instrument are considered a priori aversive, participants may not have evaluated them as such.

After evaluating the direct relationships, we proceed to the mediation test. According to the general hypothesis of the Transactional Stress Model, coping strategies serve as mediators between the stressor and the biological marker. In the present research, only two mediations were significant. The strategy Venting was configured as a mediator between Negative Events and Red Blood Cells, and between negative events and hemoglobin, corroborating the general proposition of the Transactional Stress Model, proposed by Lazarus and Folkman (1984Lazarus, R. S., & Folkman, S. (1984).Stress, appraisal, and coping. Springer publishing company.). These findings demonstrate the impact of coping strategies on understanding aspects related to stress. Faced with negative situations, higher indexes of Venting, that is, a greater tendency of the individual to vent and talk about how they feel due to the negative event, had an impact on biological markers that are related to possible infections. This demonstrates the importance of this strategy, since its use can have a positive impact on health. The other mediations found were not statistically significant.

Throughout the research, some limitations were found. One of the main concerns was the low reliability of some measures. Although it has been seen as a limitation, it is emphasized that many of the alphas found are close to those identified in the Portuguese adaptation such as Religion (.80), Acceptance (.55), Behavioral Disengagement (.78) and Substance Use (.81) (Pais-Ribeiro & Rodrigues, 2004Pais-Ribeiro, J. L., & Rodrigues, A. P. (2004). Questões acerca do coping: A propósito do estudo de adaptação do Brief Cope [Some questions about coping: the study of the Portuguese adaptation of the Bief Cope].Psicologia, Saúde & Doenças, 5(1), 3-15.).

Despite the limitations, the present research has important contributions, mainly due to the inclusion of biological markers not commonly tested in research of this nature. In addition, in the reviewed literature, no research was found that used such a large variety of coping strategies in tandem with this many biological markers. In addition, the research does not focus on a single group or patients with a specific comorbidity, in particular the sample was particularly interesting as it included low-income people, it describes a population where stress has, maybe, different pattern in stress response (Aneshensel, 1992Aneshensel, C. S. (1992). Social Stress. Annual Review Sociol, 18, 15-38. doi:10.1016/j.biopsych.2013.01.026.Cellular
https://doi.org/10.1016/j.biopsych.2013.... ), and there were no specific sample bias (some comorbid). Concerning the possible applications, the research proposed a possible practical model to test the premises of the Transactional Model of Lazarus and Folkman (1984Lazarus, R. S., & Folkman, S. (1984).Stress, appraisal, and coping. Springer publishing company.).

Other studies with this same theme should be carried out, expanding the number of participants and varying the sample to different Brazilian cities. In addition, a longitudinal study would be interesting to follow if there is a variation of the findings at different moments of life.

References

Publication Dates

History