Understanding cytokines. Part II: Implications for nursing research and practice

The Metabolomic Underpinnings of Symptom Burden in Patients With Multiple Chronic Conditions

Over 25% of the adult population in the United States suffers from multiple chronic conditions, with numbers continuing to rise. Those with multiple chronic conditions often experience symptoms or symptom clusters that undermine their quality of life and ability to self-manage. Importantly, symptom severity in those with even the same multiple chronic conditions varies, suggesting that the mechanisms driving symptoms in patients with multiple chronic conditions are not fixed but may differ in ways that could make them amenable to targeted interventions. In this manuscript we describe at a metabolic level, the symptom experience of persons with multiple chronic conditions, including how symptoms may synergize or cluster across multiple chronic conditions to augment one's symptom burden. To guide this discussion, we consider the metabolites and metabolic pathways known to span multiple adverse health conditions and associate with severe symptoms of fatigue, depression, and anxiety and their cluster. We also describe how severe versus mild symptoms, and their associated metabolites and metabolic pathways, may vary, depending on the presence of covariates; two of which, sex as a biological variable and the contribution of gut microbiota dysbiosis, are discussed in additional detail. Intertwining metabolomics and symptom science into nursing research, offers the unique opportunity to better understand how the metabolites and metabolic pathways affected in those with multiple chronic conditions may initiate or exacerbate symptom presence within a given individual, ultimately allowing clinicians to develop targeted interventions to improve the health quality of patients their families.

Shape shifters: biobehavioral determinants and phenomena in symptom research

Symptom assessment and management are critical to patient-centered care. Traditionally, the determinants of a symptom are viewed as separate from the phenomena associated with that symptom. By separating determinants and phenomena, however, the complexity and dynamism of the patient experience are ignored. Likewise, categorizing symptom determinants and phenomena as solely biological or behavioral minimizes their dimensionality and may hinder interdisciplinary dialogue. Here we propose that determinants and phenomena are not fixed but shift between each other depending on perspective. To illustrate this way of thinking the metaphor of the "shape shifter" from folklore is used. A shape shifter moves between states and may be seen differently by the same person at different times or by multiple individuals at one time. To guide discussion, we present 5 exemplars of increasing complexity, wherein a determinant becomes a phenomenon or vice versa, depending upon context. Suggestions for statistical testing of the model are included with each. We conclude by exploring how shifting between determinants and phenomena may affect symptom cluster assessment and management.

Psychosocial and biological indicators of depression in the caregiving population

Estimates suggest that 25-50% of family caregivers experience depression. Recent research has linked psychological stress and depression symptoms to increased cytokine activity. This study was designed to investigate the predictors of high cytokine levels and their influence with personality factors on depression in a caregiving population. The authors examined the relationship between caregiving burden and depression through the influence of sociotropy, autonomy, and cytokine levels in a sample of 106 caregivers who were actively caring for an elderly dependent in the community. Though the authors did not establish a mediation model, they found that the personality sub-factors of sociotropy, predicted tumor necrosis factor receptor (TNFR1) levels, while burden significantly predicted interleukin-6 and C-reactive protein (CRP) levels. Additionally, burden and TNFR1 levels predicted depression, with greater burden and TNFR1 levels predicting increased depression severity. Study findings point to a need for early interventions for caregivers to prevent increases in stress and cytokine levels and the development of depression.

Biological mechanisms related to the effectiveness of guided imagery for chronic pain

Specific aims of this pilot study were to (a) determine the effect of a guided imagery (GI) intervention over an 8-week period on pain and pain disability in a sample of persons with chronic noncancer pain (CNCP) and (b) analyze the mediating effects of neuroendocrine and neuroimmune functioning on the effectiveness of GI on outcome variables. A simple interrupted time-series design (12-week period) was used. GI was introduced at Week 4 and used daily by 25 participants for the remaining 8 weeks. Measures of pain and pain disability were obtained at the beginning of the study period and at six repeated 2-week intervals. Measures of hypothalamic-pituitary-adrenal (HPA) axis activation (plasma cortisol), immune-mediated analgesia (lymphocyte subset counts and proliferation), and immune-mediated hyperalgesia (interleukin-1β) were obtained at the beginning of the study and at Week 11. Usual pain levels were lower after the introduction of GI at Week 4 (Wilks' λ = 52.31; df = 2, 22; p = .000). Pain disability levels were lower after the introduction of GI at Week 4 (Wilks' λ = 5.98; df = 6, 18; p = .001). Correlation coefficients between change scores of dependent variables and mediating variables were not significant. GI was effective in reducing pain intensity and pain disability over an 8-week period; however, the results did not support the expected effects of decreased HPA axis activation, improved immune-mediated analgesia, and reduced immune-mediated hyperalgesia in mediating these outcomes. These findings may be related to procedural and theoretical issues and limitations related to the study design.

Targeting inflammation to slow or delay functional decline: where are we?

The role of inflammation in the pathophysiology of chronic age-related diseases is increasingly recognized, and inflammation could represent the common pathway linking diseases and disability. Thus, targeting inflammation could represent a useful strategy at preventing or delaying functional decline. In this paper we review recent evidence suggesting that selected drugs, such as statins, fibrates, angiotensin converting enzyme-inhibitors and angiotensin receptor blockers, and physical exercise may be able to contrast functional decline by blunting inflammation. Results from randomized trials investigating the effects of physical activity programs on inflammation and functional decline is still limited, and further investigations are warranted.

Integrated review of cytokines in maternal, cord, and newborn blood: part II-- associations with early infection and increased risk of neurologic damage in preterm infants

A growing body of literature supports the relationship of maternal inflammation with preterm birth and adverse neonatal outcomes, including infection and central nervous system (CNS) dysfunction. Mediators of inflammation, most notably proinflammatory cytokines, have been implicated as having an association with and perhaps playing a causal role in the pathogenesis, leading to adverse neonatal outcomes. Even though the association of cytokines with early adverse neonatal outcomes has been actively pursued as a line of research, there has been little integration of diverse findings across studies. Therefore, the purpose of this systematic review was to appraise and classify empirical evidence from human studies for the association of cytokine levels in blood (serum, plasma, or cells; maternal, cord, or neonatal) with two adverse early outcomes in preterm infants: early infection and increased risk of neurologic damage. The review revealed that the proinflammatory cytokines most frequently linked with sepsis are in the interleukin (IL) 1 family as well as tumor necrosis factor alpha (TNF-alpha) and IL-6. The proinflammatory cytokines most frequently linked to neurologic insult in the reviewed studies were IL-1beta, IL-6, and IL-8. In all cases where IL-1beta was studied, the levels were increased when there was neurologic insult. A better understanding of the relationship of these inflammatory substances with these adverse conditions is needed for the future development of maternal and neonatal biobehavioral nursing research.

Inflammation in Aging Part 2: Implications for the Health of Older People and Recommendations for Nursing Practice

Aging is accompanied by declining function and remodeling of body systems. In particular, changes to the immune and endocrine systems have far-reaching effects that cause an increase in cytokine release and decrease in anti-inflammatory feedback systems. The chronic inflammation that ensues has been named ‘‘inflammaging.’’ Inflammaging is associated with many detrimental effects that combine to increase morbidity and mortality. The sickness behavior that arises from inflammatory processes and the side effects of chronic diseases lead to a constellation of symptoms that decrease quality of life and affect the well-being of the individual. Part 2 of this two-part article provides an overview of the health effects of inflammaging, addressing the extent to which it contributes to the syndromes of frailty and disability with aging.

Inflammation and genomics in the critical care unit

Inflammation is a physiologic response to irritants, injury, and infection. Inflammatory dysregulation is believed to contribute to mortality and morbidity in illnesses common to critical care units, such as burns, trauma, sepsis, and cardiovascular disease. This article reviews the approaches used to investigate the molecular basis of inflammatory function. Genomic findings are providing insight into clinical diagnosis and treatment of inflammatory derangements in critically ill patients.

Inactivity and Inflammation in the Critically Ill Patient

Bed rest is a commonly prescribed activity restriction among patients in the ICU. Although bed rest may promote rest, recovery and safety, inactivity related to bed rest also may lead to complications and adverse outcomes. The biological mechanisms that lead to immediate and long-term sequelae from bed rest have not been elucidated. It may be the inflammatory factors common to critical illness combined with bed rest lead to a positive feedback loop, contributing to inflammatory disequilibrium. This disequilibrium has a profound affect on muscles. Muscle decay has serious and long-term adverse outcomes on survivors of critical illness. Mobility therapy may improve inflammatory disequilibrium and preserve muscles, leading to improved functional outcome. Investigations in the laboratory, in healthy people and among patients with systemic inflammatory disease, suggest that activity does not exacerbate inflammation. Clinically, exercise is beneficial to patients with various chronic inflammatory diseases. Further study is needed to best understand the role, duration, and frequency of activity in promoting recovery for critically ill patients.

A review of the role of proinflammatory cytokines in labor and noninfectious preterm labor

The prevention of preterm labor has the potential to reduce newborn morbidity and mortality by decreasing the incidence of preterm birth. Half of all preterm births occur in women with no known clinical risk factors. Labor onset and progress is multifactorial, and we are just beginning to understand the role of cytokines in uterine activity. The purpose of this article is to review the role of cytokines in labor and preterm labor not associated with infection and to provide implications for research and practice.

Inactivity and Inflammation

Muscle dysfunction leads to activity intolerance, prolonged hospitalization, and additional days of mechanical ventilation. The etiology of muscle dysfunction in the critically ill patient is multifactoral. Inactivity and inflammation, common phenomena to patients in the intensive care unit, are associated with myopathy and muscle dysfunction. Cytokines are small biological active molecules that regulate inflammation and have a direct effect on muscle wasting. The purpose of this article is to describe selected cytokines (ie, interleukin-1, interleukin-6, interleukin-10, and tumor necrosis factor), explain their role in muscle dysfunction, and explore the role of therapeutic activity as a moderator of muscle dysfunction and cytokine-mediated muscle damage.

The cellular basis of septic shock

Severe sepsis and septic shock are among the most complex and challenging conditions treated by critical care practitioners. Although the pathophysiology of severe sepsis and septic shock is not fully understood, bacteria and immune responses are known to trigger the release of cytokines. These cytokines initiate a cascade of events that lead to illness behaviors such as fever, anorexia, and sleepiness, as well as a host of physiologic events such as activation of the coagulation cascade, vasodilation, hypotension, and increased vessel permeability. As research advances the understanding of severe sepsis and septic shock, practitioners must become aware of the cellular basis of events so that treatments can be implemented knowledgeably and evaluated.

Understanding cytokines. Part I: Physiology and mechanism of action

This is the first of a 2-part article on understanding cytokines. Cytokines are intercellular signaling proteins released from virtually all nucleated cells that influence growth and cellular proliferation in a wide range of tissues. Cytokines have immune modulating effects and are understood to control most of the physical and psychological symptoms associated with infection and inflammation. Cytokines also influence reproduction and bone remodeling. Dysregulation of the cytokine cellular system has significant implications in the development of a variety of illnesses, including most autoimmune disorders, many diseases of the cardiovascular system, osteoporosis, asthma, and depression. For nurses to be adequately informed when caring for clients with chronic illnesses and to be sufficiently knowledgeable when evaluating client outcomes, an understanding of the physiology of cytokines, the occurrences of dysregulation, and the role of cytokines in health and illness is essential. In Part I of this review, cytokine physiology is presented, with an emphasis on characteristics, categories, and mechanism of action. Specific instances of cytokine function in health and disease and implications for nursing research and practice are presented in Part II.