Ziad Kronfol

Bio: Ziad Kronfol is an academic researcher from Cornell University. The author has contributed to research in topics: Lymphocyte & Depression (differential diagnoses). The author has an hindex of 32, co-authored 85 publications receiving 5788 citations. Previous affiliations of Ziad Kronfol include University of Iowa & University of Michigan.

A specific laboratory test for the diagnosis of melancholia. Standardization, validation, and clinical utility.

Abstract: • Four hundred thirty-eight subjects underwent an overnight dexamethasone suppression test (DST) to standardize the test for the diagnosis of melancholia (endogenous depression). Abnormal plasma cortisol concentrations within 24 hours after dexamethasone administration occurred almost exclusively in melancholic patients. The best plasma cortisol criterion concentration, above which a DST result may be considered abnormal, was 5 ug/dL. The optimal dose of dexamethasone was 1 rather than 2 mg. Two blood samples obtained at 4 and 11 PM after dexamethasone administration detected 98% of the abnormal test results. This version of the DST identified melancholic patients with a sensitivity of 67% and a specificity of 96%. Baseline nocturnal plasma cortisol concentrations were not useful. Abnormal DST results were found with similar frequency among outpatients and inpatients with melancholia; but they were not related to age, sex, recent use of psychotropic drugs, or severity of depressive symptoms. Extensive evidence validates this practical test for the diagnosis of melancholia.

Cytokines and the brain: implications for clinical psychiatry.

Abstract: OBJECTIVE: This article reviews recent developments in cytokine biology that are relevant to clinical psychiatry.METHOD: The authors reviewed English-language literature of the last 15 years that pertains to the biology of cytokines with emphasis on central nervous system effects in general and psychiatric disorders in particular.RESULTS: Growing evidence suggests that, in addition to providing communication between immune cells, specific cytokines play a role in signaling the brain to produce neurochemical, neuroendocrine, neuroimmune, and behavioral changes. This signaling may be part of a generalized, comprehensive mechanism to mobilize resources in the face of physical and/or psychological stress and to maintain homeostasis. The clinical implications of these findings are far-reaching and include a possible role for cytokines in the pathophysiology of specific psychiatric disorders such as major depression, schizophrenia, and Alzheimer’s disease. The effects of cytokines in the central nervous system ...

Dexamethasone suppression tests in antidepressant treatment of melancholia. The process of normalization and test-retest reproducibility.

Abstract: • Pilot studies suggest that changes in response to the dexamethasone suppression test (DST) in melancholic patients receiving antidepressants might represent a laboratory marker of clinical progress. We performed weekly DSTs in 31 hospitalized patients with major depressive disorder, primary and endogenous subtypes, during drug-free and subsequent treatment periods. Most nonsuppressors had progressive normalization of DST responses in conjunction with clinical improvement, DST normalization usually preceded or coincided with good clinical response, and failure to normalize was often associated with poorer clinical outcome. Occasional patients with baseline dexamethasone suppression become nonsuppressive after withdrawal from medication, but the DST has no apparent value as a serial marker in patients with welldocumented normal DST findings. Our results extend the construct validity of the DST as a state-related marker in nonsuppressors and suggest future clinical applications.

Subtypes of Drug Abuse With Psychosis: Demographic Characteristics, Clinical Features, and Family History

Abstract: • Hospital records of 72 drug abusers with psychoses (DAP) were analyzed to clarify the relationship between drug abuse and psychosis. Comparison groups included schizophrenics and atypical schizophrenics without drug abuse and drug abusers without psychoses (DA). Compared with DAP in whom psychoses lasted less than six months before admission (DAP-short), drug abusers with psychoses of a longer duration (DAP-long) had more symptoms, more premorbid personality disorders, and greater familial risks of schizophrenia and affective disorder. The DAP-long group resembled atypical schizophrenia for clinical features and family history, whereas the DAP-short group resembled DA for some clinical features and family history. The results indicate that there are several subgroups of DAP. The importance of clinical features and family history in identifying subgroups of DAP was stressed.

The Benefits of Being Present: Mindfulness and Its Role in Psychological Well-Being

Abstract: Mindfulness is an attribute of consciousness long believed to promote well-being. This research provides a theoretical and empirical examination of the role of mindfulness in psychological well-being. The development and psychometric properties of the dispositional Mindful Attention Awareness Scale (MAAS) are described. Correlational, quasi-experimental, and laboratory studies then show that the MAAS measures a unique quality of consciousness that is related to a variety of well-being constructs, that differentiates mindfulness practitioners from others, and that is associated with enhanced selfawareness. An experience-sampling study shows that both dispositional and state mindfulness predict self-regulated behavior and positive emotional states. Finally, a clinical intervention study with cancer patients demonstrates that increases in mindfulness over time relate to declines in mood disturbance and stress. Many philosophical, spiritual, and psychological traditions emphasize the importance of the quality of consciousness for the maintenance and enhancement of well-being (Wilber, 2000). Despite this, it is easy to overlook the importance of consciousness in human well-being because almost everyone exercises its primary capacities, that is, attention and awareness. Indeed, the relation between qualities of consciousness and well-being has received little empirical attention. One attribute of consciousness that has been much-discussed in relation to well-being is mindfulness. The concept of mindfulness has roots in Buddhist and other contemplative traditions where conscious attention and awareness are actively cultivated. It is most commonly defined as the state of being attentive to and aware of what is taking place in the present. For example, Nyanaponika Thera (1972) called mindfulness “the clear and single-minded awareness of what actually happens to us and in us at the successive moments of perception” (p. 5). Hanh (1976) similarly defined mindfulness as “keeping one’s consciousness alive to the present reality” (p. 11). Recent research has shown that the enhancement of mindfulness through training facilitates a variety of well-being outcomes (e.g., Kabat-Zinn, 1990). To date, however, there has been little work examining this attribute as a naturally occurring characteristic. Recognizing that most everyone has the capacity to attend and to be aware, we nonetheless assume (a) that individuals differ in their propensity or willingness to be aware and to sustain attention to what is occurring in the present and (b) that this mindful capacity varies within persons, because it can be sharpened or dulled by a variety of factors. The intent of the present research is to reliably identify these inter- and intrapersonal variations in mindfulness, establish their relations to other relevant psychological constructs, and demonstrate their importance to a variety of forms of psychological well-being.

Impact of psychological factors on the pathogenesis of cardiovascular disease and implications for therapy.

Abstract: Recent studies provide clear and convincing evidence that psychosocial factors contribute significantly to the pathogenesis and expression of coronary artery disease (CAD). This evidence is composed largely of data relating CAD risk to 5 specific psychosocial domains: (1) depression, (2) anxiety, (3) personality factors and character traits, (4) social isolation, and (5) chronic life stress. Pathophysiological mechanisms underlying the relationship between these entities and CAD can be divided into behavioral mechanisms, whereby psychosocial conditions contribute to a higher frequency of adverse health behaviors, such as poor diet and smoking, and direct pathophysiological mechanisms, such as neuroendocrine and platelet activation. An extensive body of evidence from animal models (especially the cynomolgus monkey, Macaca fascicularis) reveals that chronic psychosocial stress can lead, probably via a mechanism involving excessive sympathetic nervous system activation, to exacerbation of coronary artery atherosclerosis as well as to transient endothelial dysfunction and even necrosis. Evidence from monkeys also indicates that psychosocial stress reliably induces ovarian dysfunction, hypercortisolemia, and excessive adrenergic activation in premenopausal females, leading to accelerated atherosclerosis. Also reviewed are data relating CAD to acute stress and individual differences in sympathetic nervous system responsivity. New technologies and research from animal models demonstrate that acute stress triggers myocardial ischemia, promotes arrhythmogenesis, stimulates platelet function, and increases blood viscosity through hemoconcentration. In the presence of underlying atherosclerosis (eg, in CAD patients), acute stress also causes coronary vasoconstriction. Recent data indicate that the foregoing effects result, at least in part, from the endothelial dysfunction and injury induced by acute stress. Hyperresponsivity of the sympathetic nervous system, manifested by exaggerated heart rate and blood pressure responses to psychological stimuli, is an intrinsic characteristic among some individuals. Current data link sympathetic nervous system hyperresponsivity to accelerated development of carotid atherosclerosis in human subjects and to exacerbated coronary and carotid atherosclerosis in monkeys. Thus far, intervention trials designed to reduce psychosocial stress have been limited in size and number. Specific suggestions to improve the assessment of behavioral interventions include more complete delineation of the physiological mechanisms by which such interventions might work; increased use of new, more convenient "alternative" end points for behavioral intervention trials; development of specifically targeted behavioral interventions (based on profiling of patient factors); and evaluation of previously developed models of predicting behavioral change. The importance of maximizing the efficacy of behavioral interventions is underscored by the recognition that psychosocial stresses tend to cluster together. When they do so, the resultant risk for cardiac events is often substantially elevated, equaling that associated with previously established risk factors for CAD, such as hypertension and hypercholesterolemia.

Associations of Depression With C-Reactive Protein, IL-1, and IL-6 : A Meta-Analysis

Abstract: Objective:To assess the magnitude and direction of associations of depression with C-reactive protein (CRP), interleukin (IL)-1, and IL-6 in community and clinical samples.Methods:Systematic review of articles published between January 1967 and January 2008 in the PubMed and PsycINFO electronic data

The Neuroendocrinology of Stress and Aging: The Glucocorticoid Cascade Hypothesis

Abstract: Over the past 5 yr, we have examined some of the sharpest edges of the pathology of aging. We have studied the capacity of aged organisms to respond appropriately to stress and the capacity of stre...