Resiliencia: ¿Es posible medirla e influir en ella? / Resilience: is it possible to measure and influence it?

ABSTRACT

The objective of this work is to present a review about the concept of resilience, its biological aspects, the way we can try to measure it and some possible interventions. In Spanish, the term resiliencia is taken from the English word resilience or resiliency, term originally used in thermodynamics. In biological sciences, resilience is defined as <ecosystem or organism to recover its steadiness after it has suffered an alteration>>. In psychosocial research, Rutter defines resilience as <risk>>. For the resilience process to take place, it is necessary that individuals become exposed to an important stress and adversity load, and their efforts to contend them result in a positive adaptation in spite of suffering aggressions throughout the developmental process. When facing significant stress, three potential responses can be anticipated 1. That individuals at risk show a better evolution than expected; 2. That a positive adaptation remains in spite of stressing experiences; or 3. That individuals reach an acceptable recovery after a trauma. The physiological response to the acute stress involves several neurotransmitters, neuropeptides and hormones, which have functional interactions that may produce a psychobiological response in the face of the acute stress and long term psychiatric consequences because they mediate mechanisms and neuronal paths that regulate reward, fear conditioning and social behavior. Cortisol, corticotropin-releasing hormone, norepinephrine, galanin, neuropeptide Y, dopamine and serotonin are some of the substances (physiological [or stress] mediators) implicated. After important stress exposure, we can say that a person has a resilient profile if his/her dehydroepiandrosterone (DHEA), neuropeptide Y, galanin, testosterone, 1A serotonin receptor (5HT1A) and benzodiazepine receptor levels are increased at the time that the hypothalamic-pituitary-adrenal axis (HPAA) and the locus coeruleus system functions are diminished. The biological factors associated with the acute and chronic stress can be considered a measure of resilience. For this purpose, the term allostasis, defined as the adaptive physiological response against the acute stress, has been proposed. Ideally, once the acute stress is suppressed, the individual is capable of recovering the state of homeostasis. However, if this does not occur and adaptive response against the acute stress persists or decreases only partially, it results in a harmful cumulative effect on the physiological and psychological functions of the individual. This phenomenon is denominated <<allostatic load>>. To evaluate the allostatic load it is necessary to incorporate information on the <allostasis, and to evaluate the dynamics of the systems and the parameters of the main regulation systems. The parameters to evaluate the allostatic load are a) Arterial systolic pressure >148 mmHg and arterial diastolic pressure >83 mmHg, which are the cardiovascular activity index; b) Waist-hip index > 0.94, that reflects the chronic metabolism function and the disposition of body fat; c) The total cholesterol/high density lipids (HDL)relation in serum >5.9, related with the development of atherosclerosis; d) Glycosylated hemoglobin levels >7.1%, to identify the average of plasma glucose concentration over prolonged periods of time; e) Dehydroepiandrosterone sulfate (DHEA-S) <350 ng/ml, a functional antagonist of the HPAA; f) Nocturnal urinary cortisol excretion ratio >25.7 ug/g creatinine, which measures the 12 hours HPAA activity; g) Nocturnal urinary adrenaline >48 ug/g creatinine, and noradrenaline excretion >5 ug/g creatinine; this test integrates the 12-hours indexes of the sympathetic nervous system activity. The appropriate study of resilience requires consideration to other aspects influencing its nature besides the biological ones. Some of them are a) The risk factors, defined as events or conditions of adversity associated with the presence of psychopathology or dysfunctional development; b) The vulnerability factors, that is, the features, genetic biases and environmental or biological deficiencies which increase the stress and risk factors response; and c) The protective factors, described as features, contextual characteristics and interventions that promote the resistance, or moderate the effects, to the risk factors. The protective factors are associated with health and functional development; therefore, they promote resilience and offer new options to cope with the event. These factors are studied in three areas those characteristic of children, in the family atmosphere and in the community. The characteristic factors of children are intelligence, temperament, flexibility, sense of humor and self-esteem. Related to these a number of annotations have been made. For instance, in certain individual intelligence is modified due to a sequence of stress exposure, like family violence. Individuals with a <personality experience more trust and are better prepared to apply their abilities and take advantage of their social support; likewise, cooperativeness, kindliness and tolerance are characteristics that could help the child to deal with the presence of harsh conditions; and finally, people with a high opinion of themselves seem to be more resistant to stressing events. The factors of the family atmosphere are maltreatment, parental loss, attachment and support, discipline and surveillance, carefulness and parents' mental illness. Regarding these factors it is possible to say that abuse can result in a disturbance of the normal development. Whereas a good care quality educational opportunities, appropriate nutrition and support from the community to the families, during the early childhood, propitiate a positive development at a cognitive, social and self-regulation level in both children and adolescents. It is known that resilient boys come from homes with structure and rules. For these children, the role of a healthy and reliable paternal figure serves as a model for identity and for the appropriate emotional expression. Instead, the resilient girls develop in homes that combine the emphasis in the taking of risks as well as the independence, besides they are supported by a caregiver. Finally, the factors in the community are violence, social networks and neighborhood. It has been recognized that children who live in violent neighborhoods have a high risk of developing internalized and externalized disorders. Nevertheless, the acceptance of their peers and their friendships can attenuate their family adversity, what surely helps them to acquire social abilities; in that same direction, an appropriate social organization can reduce the impact of poverty and violence in the community. It is important to mention that these factors continually interact with each other (and should not be seen in an isolated way) in what we call adaptive systems, those which directly contribute to the satisfactory adjustment or recovery of balance after the exposure to one or more adverse events. When these adaptive systems are available and work properly, the individuals are said to be resilient. We know that in these adaptive systems, mainly in the first stages of life, a disturbance can exist as a consequence of chronic or acute exposure of the individual to adversity. The adaptive systems are as follows learning, attachment, motivation, response to stress, selfmodulation, family, school, pairs, cultural and social systems.

RESUMEN

El objetivo de este trabajo es hacer una revisión acerca del concepto de resiliencia, sus aspectos biológicos, las formas en las que se puede intentar medirla y algunas posibles intervenciones. El término resiliencia es una castellanización de la palabra inglesa resilience o resiliency, que originalmente se usaba en la termodinámica. En las ciencias biológicas se define como <ecosistema o de un organismo para regresar a la estabilidad al sufrir una alteración>>. En la investigación psicosocial, Rutter define a la resiliencia como <riesgo>>. Para que el proceso de resiliencia se pueda presentar, es necesario que el individuo se encuentre expuesto a una importante carga de estrés y adversidad, donde sus esfuerzos por contenderla terminan orientándose hacia una adaptación positiva a pesar de sufrir agresiones a lo largo del proceso de desarrollo. Se pueden anticipar tres escenarios de respuesta que los individuos en riesgo muestren una mejor evolución a la esperada, que una adaptación positiva se mantenga a pesar de experiencias estresantes, o que se llegue a una buena recuperación después de un trauma. En la respuesta fisiológica ante el estrés agudo participan diversos neurotransmisores, neuropéptidos y hormonas, los cuales tienen interacciones funcionales que pueden producir una respuesta psicobiológica al estrés agudo y consecuencias psiquiátricas a largo plazo debido a que median mecanismos y circuitos neuronales que regulan la recompensa, el condicionamiento al miedo y la conducta social. Entre ellas están el cortisol, la hormona liberadora de corticotropina, la norepinefrina, la galanina, el neuropéptido Y, la dopamina y la serotonina. Para medir la resiliencia se deben tomar en cuenta los factores biológicos asociados al estrés agudo y crónico. Para este fin se ha acuñado el término alostasis, el cual se define como una respuesta fisiológica adaptativa ante el estrés agudo. Lo ideal es que una vez suprimido el estrés agudo se llegue a un estado de homeostasis. Sin embargo, si esto no se lleva a cabo y la respuesta adaptativa ante el estrés persiste o disminuye sólo de forma parcial, se presentan efectos dañinos sobre la función fisiológica y psicológica que se van acumulando; este fenómeno se denominó <<carga alostática>>. Para evaluar la carga alostática se debe incorporar información sobre los niveles <alostasis de cada individuo; también evaluar la dinámica de los sistemas y los parámetros de los sistemas reguladores mayores. Además de los aspectos biológicos, para el estudio de la resiliencia se deben tener en cuenta otros factores que podrían contribuir a que el proceso resiliente se inicie o no; es decir, los factores de riesgo y vulnerabilidad y los factores protectores. Estos factores se estudian en tres áreas los propios de los niños, en el ambiente familiar y en la comunidad. Los factores propios del niño son inteligencia, temperamento, flexibilidad, sentido del humor y autoestima. Los factores del ambiente familiar son maltrato, pérdida parental, apego y apoyo, disciplina y monitorización, calidez y enfermedad mental de los padres. Los factores en la comunidad son violencia, redes sociales, vecindario. Partiendo de estos factores se pueden organizar sistemas adaptativos, que pueden ser individuales aprendizaje, apego, motivación, respuesta al estrás y auto regulación; y socioculturales familiar, escolar, pares, cultural y social. Estudios en niños maltratados han permitido identificar genes implicados en la protección o disminución del riesgo para desarrollar psicopatología. Ciertos genotipos confieren protección para depresión, esquizofrenia, abuso de sustancias o maltrato. Conociendo algunos de los factores que contribuyen a la resiliencia y que se han estudiado en poblaciones en que se corrobora dichas contribuciones, se puede formular la siguiente pregunta ?Será posible intervenir en poblaciones de riesgo? Partiendo del punto de que los niños sufren daño debido a que sus sistemas adaptativos están siendo atacados y que no se han desarrollado completamente, es posible prevenir el daño, reparar o hacer mejor estos sistemas adaptativos.