Elevated platelet factor 4 and beta-thromboglobulin plasma levels in depressed patients with ischemic heart disease

Platelet hyperactivity in clinical depression and the beneficial effect of antidepressant drug treatment: how strong is the evidence?

OBJECTIVE

Platelet hyperactivity is thought to contribute to the increased coronary artery disease (CAD) risk in depression. This study reviewed the evidence for hyperactive platelets and for effects of antidepressant drug treatment on platelet 'stickiness' in clinical depression.

METHOD

By means of PubMed electronic library search, 34 studies in English were identified (1983-2003) and critically reviewed.

RESULTS

In depression, flow cytometry studies allowing detection of subtle platelet activation states consistently found at least one platelet activation marker to be increased, while the bulk of platelet aggregation studies did not suggest increased platelet aggregability. Platelets seem to be more activated in depressed patients with CAD than in depressed individuals without CAD. The selective serotonin reuptake inhibitors normalized platelet hyperactivity in four studies.

CONCLUSION

Data on platelet activity in depression are inconclusive. To resolve this issue and its clinical implications, studies in larger sample sizes controlling for confounders of platelet functioning and prospectively designed are needed.

Decreased platelet nitric oxide synthase activity and plasma nitric oxide metabolites in major depressive disorder

BACKGROUND

Major depression (MD) has been associated with increased cardiovascular mortality in patients with coronary heart disease (CHD) and has been described as an independent risk factor for the development of CHD in healthy subjects; however, the mechanism of the association between MD and CHD remains to be determined. Nitric oxide (NO) plays a major role in cardiovascular regulation, and decreased NO production has been associated with several cardiovascular risk factors. We hypothesized that in patients with MD, NO production by both platelets and the endothelium would be reduced when compared with healthy control subjects (HCs).

METHODS

Blood samples were obtained from 15 subjects with MD and 16 HCs with no known history of cardiovascular illness. Plasma NO metabolite (NOx) levels were analyzed by chemiluminescence. Platelet endothelial NO synthase (eNOS) activity was examined through the conversion of l-[(14)C]arginine to l-[(14)C]citrulline.

RESULTS

The levels of both plasma NOx and platelet eNOS activity were significantly lower in subjects with MD compared with HCs.

CONCLUSIONS

These data suggest that decreased NO production by the vascular wall and platelets might contribute to the increased CHD risk observed in patients with MD.

Geriatric depression and vascular diseases: what are the links?

BACKGROUND

The term "vascular depression" has been proposed to describe a subset of depressive disorders that occurs in old age as a consequence of cerebrovascular disease. However, depression has been shown to result from other cardiovascular diseases such as coronary heart diseases, as well as to precipitate, worsen or precede vascular diseases. Depression also increases the likelihood of the incidence of vascular risk factors such as diabetes.

AIMS

To review clinical and epidemiological evidence linking geriatric depression and vascular diseases, and to discuss the potential mechanisms that could underlie this association.

METHOD

Systematic review of the literature of the last 5 years through Medline database search.

RESULTS

Papers report the following potential ways of association: (1) there is a direct influence of vascular disease, in particular, arteriosclerosis, on the incidence of depression; (2) depressive disorders have a direct impact on the cardiovascular system; (3) depression and vascular disease share either a common pathophysiological process or genetic determinants.

DISCUSSION

Depression can be understood as the direct consequence of brain damage in neurodegenerative disorders such as Parkinson's or Huntington's diseases. Similarly, vascular depression is mostly considered to be the consequence of microvascular lesions on prefrontal and subcortical regions. However, this functional neuroanatomical model offers no explanation for cases where depression has been shown to precede vascular diseases. Since cardiovascular diseases develop in a context of acquired environmental factors together with genetically determined disease, it may be postulated that geriatric depression could both result from brain lesions of vascular origin and also share some pathogenic or genetic determinants.

Should selective serotonin reuptake inhibitors be prescribed to all patients with ischemic heart disease?

Recent studies have uncovered more and more evidence demonstrating the adverse relationship between depression and ischemic heart disease. One of the most significant mechanisms that may explain the adverse relationship is the increased platelet activity, otherwise known as aggregation, observed to occur in patients with depression or ischemic heart disease. Platelet activity is further elevated in patients with depression and ischemic heart disease. Selective serotonin reuptake inhibitors are antidepressants and also act like platelet inhibitors. The results of large-scale clinical trials suggest that the use of selective serotonin reuptake inhibitors may reduce cardiac events in post-myocardial infarction patients or in those with unstable angina that may be related to the effects of selective serotonin reuptake inhibitors on platelet aggregation.

Depression in the elderly: new concepts and therapeutic approaches

Depression is one of the leading causes of suffering in the elderly, but it is often under-diagnosed and under-treated, partly due to the false belief that depression is a common aspect of aging. Depression in the elderly is frequently comorbid with medical illnesses, may often be expressed by somatic complaints, and may be a risk factor for other diseases such as dementia and coronary artery disease. Depression decreases the quality of life and increases disability and the risk of mortality, also due to suicide. Although several effective antidepressant drugs are available, with a favorable therapeutic index, non-pharmacological treatments, such as psychotherapy and exercise, should receive greater attention, since combination therapy is probably more effective.

Effects of depressive symptoms and anxiety on hemostatic responses to acute mental stress and recovery in the elderly

Depression and anxiety are prospectively associated with cardiac morbidity and mortality. Increased clotting diathesis may mediate this link. We hypothesized that there would be an association between mood and hemostatic changes that occur during and following recovery from acute mental stress. Forty-eight community-dwelling elderly subjects underwent a laboratory speech stressor task. Plasma von Willebrand factor (vWF), thrombin/antithrombin III (TAT) complexes, D-dimer, tissue-type plasminogen activator (t-PA), and type I plasminogen activator inhibitor (PAI-1) were measured at rest, after conclusion of the speech, and 14 min afterwards (recovery). Mood was assessed with the Hamilton Rating Scales for Depression (Ham-D) and Anxiety (Ham-A). Mental stress elicited a hypercoagulable state as evidenced by increases in TAT and D-dimer, and by a decrease in t-PA. Overall, hypercoagulability had increased after recovery. Ham-D scores and Ham-A scores correlated with increases in D-dimer over the testing interval (i.e. area under the curve). Ham-A (but not Ham-D) uniquely explained 8% and 17% of the variance in resting D-dimer and D-dimer area under the curve, respectively. The independent association of anxiety symptoms with resting and stress-induced fibrin formation (D-dimer) may be a mechanism linking mood with cardiovascular disease risk in the elderly.

Psychological theories of depression: potential application for the prevention of acute coronary syndrome recurrence

The natural course of elevated depressive symptoms or subthreshold depression in patients with an acute coronary syndrome (ACS) is presented, as is the prognostic impact. Safe and effective psychological treatment options are desirable for subthreshold depression in patients with ACS, should they prove tolerable, efficacious, and cost-effective to cardiologists and their patients. To achieve this long-term goal, we propose focusing on 3 intermediate goals. First, we need to understand which symptoms or patterns of symptoms (eg, fatigue, anhedonia, guilt feelings) are specifically predictive of ACS recurrence. Second, the prevalence of known psychosocial vulnerabilities (proximal causes) of depressive disorders should be assessed in patients with ACS, to understand better the etiology of these symptoms in these patients. Third, randomized controlled trials of vulnerability-related, evidence-based psychological depression interventions in cardiac patients are needed. The ways in which psychological proximal cause theories are relevant--or irrelevant--for both the treatment of depressive symptoms in post-ACS patients and the prevention of ACS recurrence are discussed.

Synthesis of dinucleoside tetraphosphates in transfected cells by a firefly luciferase reporter gene

The firefly luciferase gene is widely used as a reporter gene and its expression is generally considered to be non-toxic. In addition to its light-producing reaction, luciferase can synthesise dinucleoside polyphosphates, intracellular signalling molecules, in vitro. Here we show that COS-7 cells transfected with a luciferase expression vector accumulate up to 0.5 mM adenine-containing dinucleoside tetraphosphates (Ap4N) during the 24 h following luciferin addition. The optimal external concentration of luciferin was 0.4-0.6 mM. In agreement with its poor ability to synthesise adenine-containing dinucleoside triphosphates in vitro, the level of these compounds did not increase after transfection. Consequently, the results of experiments involving luciferase-mediated light production by live cells should now be viewed in the light of the possible effects of an increased intracellular Ap4N concentration on the properties of the system under investigation. This observation also points to a useful non-invasive procedure for the specific enhancement of intracellular Ap4N for studies directed at understanding the functions of these compounds.

Health-related quality of life in elderly chinese patients with heart failure

Heart failure (HF) has a profound impact on patients' health-related quality of life (HRQL). Little is known about factors relating to HRQL in elderly Chinese HF patients. The objective of this cross-sectional correlational study was to identify the demographic, psychosocial, and clinical factors associated with HRQL in this group of patients. Cross-sectional data were obtained from a consecutive sample of hospitalized HF patients (n = 227) with measures of HRQL, psychological distress, perceived social support, and health perception. Functional status was measured with the New York Heart Association Classification (NYHA). In stepwise regression analysis, four variables, including psychological distress, health perception, NYHA classification, and educational level explained 51.8% (p =.01) of the variance in HRQL. These findings suggest that improving HRQL of HF patients entails improving their psychological status, functional status, and health perception.

Cardiovascular health and depression

Research has shown that depression increases the likelihood that otherwise healthy people will develop ischemic heart disease (IHD) and worsens the prognosis of patients who already have IHD. Moreover, concerns about safety (e.g., cardiac side effects, drug-drug interactions) have caused physicians to be hesitant about using antidepressant agents in patients with IHD. This article is based on a recent roundtable of experts who met to discuss risk, diagnosis, and treatment options for depression in patients with IHD. This article reviews clinical and epidemiological studies that have described a link between depression and the subsequent development of IHD and have examined the role of depression as a predictor of cardiac events in patients with existing IHD. The article addresses the issue of whether depression can be safely and efficaciously treated both in patients with stable IHD and in those with acute coronary syndromes. The authors discuss safety issues related to the potential for interactions between antidepressants and cardiovascular medications, the use of nonpharmacologic treatment options such as psychosocial interventions, and the effect of antidepressant therapy on quality of life in patients with IHD. The article concludes with practical clinical guidance concerning the management of depression in patients who have recently experienced myocardial infarction.

Zur Bedeutung depressiver Störungen für die somatische Medizin/ The importance of depressive disorders in somatic medicine

Depressive disorders--including mild and subthreshold forms--are frequent in medical patients, although often not recognized. Over the past decades accumulating scientific evidence has demonstrated their clinical relevance. Depressive disorders and also elevated scores on self-rating scales for depressive symptoms are clearly related to disease behavior and quality of life. In many physical conditions they also predict adverse outcome, including premature death. This paper gives an overview of the literature on the relevance and treatment of comorbid depression in patients with HIV infection, cancer and coronary heart disease. It shows that the subjective effects of depression are rather similar in different somatic conditions. In addition, depression also interacts with the physical course of different diseases. However, the specific physiological mediators involved vary among different somatic diseases and have not yet been completely understood. Despite this uncertainty an improved recognition and treatment of comorbid depression can be recommended. Supportive interventions focussing on coping demands as well as regular psychotherapy and in some cases antidepressant medication may be indicated. While it still appears premature to establish generally applicable treatment guidelines, an individualized approach with regard to the different treatment alternatives for individual patients should be advocated.

Enhanced platelet/endothelial activation in depressed patients with acute coronary syndromes: evidence from recent clinical trials

Platelets play a key role in the progression of acute coronary syndromes (ACS). Clinical depression alone is also associated with enhanced platelet activation. The purpose of this study was to compare concentrations of established biomarkers of enhanced platelet/endothelial activation in clinically depressed versus non-depressed patients enrolled in recent clinical trials for ACS. Two hundred and eighty-one baseline plasma samples from patients with acute myocardial infarction (ASSENT-2; n = 41), with ACS (PRONTO; n = 126) and with clinical depression plus previous acute coronary syndrome within 6 months (SADHART; n = 64), and from normal healthy controls (n = 50) were analyzed. Blood was drawn before applying any therapeutic strategies including interventions, thrombolytics, infusions, and selective serotonin re-uptake inhibitors. Platelet factor 4, beta-thromboglobulin, platelet/endothelial cell adhesion molecule-1, P-selectin, thromboxane, prostacyclin, vascular cell adhesion molecule-1, and E-selectin were measured by enzyme-linked immunosorbent assay by a single core laboratory. Patients with ACS exhibited a higher degree of platelet activation than controls independently of the presence of depression. Plasma levels of P-selectin, thromboxane, prostacyclin, and vascular cell adhesion molecule-1 were the highest in the acute myocardial infarction group when compared with ACS despite the presence or absence of clinical depression. Surprisingly, patients with ACS and depression exhibited the highest levels of platelet factor 4, beta-thromboglobulin, and platelet/endothelial cell adhesion molecule-1 when compared with myocardial infarction or angina patients without clinical depression. E-selectin plasma level was constantly elevated compared with controls but did not differ among the groups dependent on the incidence of depression. The depressed plus ACS group had higher plasma levels of all biomarkers compared with the non-depressed patients. Retrospective analysis of the data from several clinical trials reveals that clinical depression is associated with enhanced activation of platelet/endothelial biomarkers even above the level expected in ACS. These findings may contribute to the unfavorable outcome associated with clinical depression in patients with ACS.

Increased coronary events in depressed cardiovascular patients: 5-HT2A receptor as missing link?

OBJECTIVE

Major depressive disorder and depressive symptoms have been identified as independent risk factors for cardiac morbidity and mortality in patients with ischemic heart disease. Increased susceptibility to platelet activation has been proposed as one of the mechanisms by which depression acts as a significant risk factor for thrombotic events. In this review, data on platelet activation and platelet aggregation measures in depressed patients with or without concomitant cardiovascular disease are given. Data on the influence of antidepressants on parameters of platelet activation are summarized.

METHODS

A literature search was done by checking MEDLINE Advanced and PsycInfo from 1990 to 2003 and through checking the bibliographies of these sources. The following key words were used for this search: platelet activation, platelet aggregation, depression, depressive disorder, ischemic heart disease, calcium, and serotonin.

RESULTS

There is an indication of enhanced platelet activation and aggregation in depressed patients. Next, patients with a depressive disorder show signs of a hyperactive platelet 5-HT2A receptor signal transduction system as measured by increased platelet calcium mobilization after stimulation of platelets with serotonin.

CONCLUSIONS

Depression appears to be associated with an increased susceptibility for serotonin-mediated platelet activation. Upregulation and/or increased sensitivity of 5-HT2A/1B receptors and downregulated 5-HT transporter receptors in the periphery may contribute to increased risk of thromboembolic events in patients with depression and cardiovascular disease. Increased platelet reactivity based on a hyperreactive 5-HT2A receptor signaling system might be influenced by antidepressive medication that antagonizes platelet 5-HT2A receptors.

Platelet/endothelial biomarkers in depressed patients treated with the selective serotonin reuptake inhibitor sertraline after acute coronary events: the Sertraline AntiDepressant Heart Attack Randomized Trial (SADHART) Platelet Substudy

BACKGROUND

Depression after acute coronary syndromes (ACSs) has been identified as an independent risk factor for subsequent cardiac death. Enhanced platelet activation has been hypothesized to represent 1 of the mechanisms underlying this association. Selective serotonin reuptake inhibitors (SSRIs) are known to inhibit platelet activity. Whether treatment of depressed post-ACS patients with SSRIs alters platelet function was not known. Accordingly, we serially assessed the release of established platelet/endothelial biomarkers in patients treated with sertraline vs placebo in the Sertraline AntiDepressant Heart Attack Randomized Trial (SADHART).

METHODS AND RESULTS

Plasma samples (baseline, week 6, and week 16) were collected from patients randomized to sertraline (n=28) or placebo (n=36). Anticoagulants, aspirin, and ADP-receptor inhibitors were permitted in this study. Platelet factor 4, beta-thromboglobulin (betaTG), platelet/endothelial cell adhesion molecule-1, P-selectin, thromboxane B2, 6-ketoprostaglandin F1a, vascular cell adhesion molecule-1, and E-selectin were measured by ELISA. Treatment with sertraline was associated with substantially less release of platelet/endothelial biomarkers than was treatment with placebo. These differences attained statistical significance for betaTG (P=0.03) at weeks 6 and 16 and for P-selectin (P=0.04) at week 16. Repeated-measures ANOVA revealed a significant advantage for sertraline vs placebo for diminishing E-selectin and betaTG concentrations across the entire treatment period.

CONCLUSIONS

Treatment with sertraline in depressed post-ACS patients is associated with reductions in platelet/endothelial activation despite coadministration of widespread antiplatelet regimens including aspirin and clopidogrel. The antiplatelet and endothelium-protective properties of SSRIs might represent an attractive additional advantage in patients with depression and comorbid coronary artery and/or cerebrovascular disease.

Paroxetine-induced increase in metabolic end products of nitric oxide

Decreased production of endothelium-derived nitric oxide has been implicated in the pathogenesis of cardiovascular diseases. Metabolic end products of nitric oxide (NO(x)) are often used as markers for endothelial nitric oxide production in humans. Decreased endothelium-derived nitric oxide has been suggested to mediate some of the deleterious effects of conventional cardiovascular risk factors such as hypercholesterolemia, smoking, and physical inactivity. A substantial number of patients with cardiovascular diseases suffer from comorbid major depressive disorder, which is a predictor of a poorer cardiovascular outcome. Paroxetine is a first-line antidepressant and has been reported to decrease plasma NO(x), theoretically suggesting a potential deleterious effect on the cardiovascular system. We assessed the hypothesis that paroxetine would induce a decrease in plasma NO(x) in healthy volunteers. Plasma NO(x) levels were measured by chemiluminescence at baseline, after 8 weeks of paroxetine administration, and at postdiscontinuation. Contrary to our hypothesis, we found that paroxetine administration induced a significant increase in NO(x) that normalized after paroxetine discontinuation. It remains to be demonstrated that the paroxetine-induced increase in NO(x) is associated with a modification of the cardiovascular risk in patients with major depressive disorder.

Depression and cardiovascular disease: mechanisms of interaction

This article explores the relationship between depression and cardiovascular disease from a mechanistic standpoint. Depression and cardiovascular disease are two of the most prevalent health problems in the United States and are the two leading causes of disability both in the United States and worldwide. Although depression is a known risk factor for the development of cardiovascular disease, as well as an independent predictor of poor prognosis following a cardiac event, the mechanistic relationship between the two remains unclear. Depression is associated with changes in an individual's health status that may influence the development and course of cardiovascular disease, including noncompliance with medical recommendations, as well as the presence of cardiovascular risk factors such as smoking and hypertension. In addition, depression is associated with physiologic changes, including nervous system activation, cardiac rhythm disturbances, systemic and localized inflammation, and hypercoagulability, that negatively influence the cardiovascular system. Further, stress may be an underlying trigger that leads to the development of both depression and cardiovascular disease. This article reviews seven potential mechanisms for the relationship between depression and cardiovascular disease and presents the available evidence surrounding each mechanism. Finally, future directions for research are discussed.

Clinical and health services relationships between major depression, depressive symptoms, and general medical illness

Patients with chronic medical illness have a high prevalence of major depressive illness. Major depression may decrease the ability to habituate to the aversive symptoms of chronic medical illness, such as pain. The progressive decrements in function associated with many chronic medical illnesses may cause depression, and depression is associated with additive functional impairment. Depression is also associated with an approximately 50% increase in medical costs of chronic medical illness, even after controlling for severity of physical illness. Increasing evidence suggests that both depressive symptoms and major depression may be associated with increased morbidity and mortality from such illnesses as diabetes and heart disease. The adverse effect of major depression on health habits, such as smoking, diet, over-eating, and sedentary lifestyle, its maladaptive effect on adherence to medical regimens, as well as direct adverse physiologic effects (i.e., decreased heart rate variability, increased adhesiveness of platelets) may explain this association with increased morbidity and mortality.

Cognitive and somatic symptoms of depression are associated with medical comorbidity in patients after acute myocardial infarction

BACKGROUND

Depression is common in patients with acute myocardial infarction (AMI) and is associated with adverse health outcomes. However, the extent to which clinical depression is related to comorbid medical conditions is unknown. This study examined the degree of association between clinical depression and medical comorbidity in patients hospitalized with AMI.

METHODS

Two thousand four hundred and eighty-one depressed or socially isolated patients with AMI were enrolled, as part of the National Heart, Lung, and Blood Institute-sponsored Enhancing Recovery in Coronary Heart Disease clinical trial. A structured interview was used to diagnose major and minor depression and dysthymia; severity of depression was measured by the Hamilton Rating Scale for Depression and the Beck Depression Inventory. Level of social support was measured by the ENRICHD Social Support Instrument. A modified version of the Charlson Comorbidity Index was used to measure the cumulative burden of medical comorbidity.

RESULTS

The adjusted odds ratios (ORs) for having major depression increased linearly with medical comorbidity (ORs 1.6, 2.2, 2.7 for each increasing medical comorbidity category). This relationship remained after adjusting for coronary heart disease severity (ORs 1.4, 1.7, 1.9, P <.001). The relationship between severity of depression and medical comorbidity was also maintained after excluding somatic symptoms of depression (F = 21.5, P <.0001).

CONCLUSIONS

Patients with AMI and clinical depression have significantly greater levels of medical comorbidity than nondepressed, socially isolated patients. Further research is needed to determine whether comorbid medical illness contributes to the more frequent rehospitalizations and increased risk of mortality associated with depression.

A twin study of depression symptoms, hypertension, and heart disease in middle-aged men

OBJECTIVE

Epidemiological and clinical studies have established an association between major depression and cardiovascular disease. We utilized a twin design to test whether there are common genetic and environmental risk factors underlying depression symptoms, hypertension and heart disease.

METHODS

Association studies were conducted with 6,903 male-male twins from the Vietnam Era Twin Registry who responded to both a 1990 health questionnaire and a 1992 telephone administration of a structured psychiatric interview. Data from 2,731 complete twin pairs were used to fit genetic models which determined the extent to which lifetime depression symptoms, heart disease and hypertension shared genetic and/or environmental factors.

RESULTS

Heart disease was significantly associated with 1-4 symptoms and 5 or more symptoms of depression (odds ratio [OR] = 2.62; 95% confidence interval [CI]: 1.54-4.46 and OR = 4.02; 95% CI: 2.16-7.46). Hypertension was significantly associated with 1 to 4 symptoms and 5 or more symptoms of depression (OR = 1.29; 95% CI: 1.11-1.50 and OR = 1.49; 95% CI: 1.21-1.83). The genetic correlations were significant between depression symptoms and hypertension (r =.19), and between depression symptoms and heart disease (r =.42). Of the total variance in depression, 8% was common to hypertension and heart disease, 7% of the variance in hypertension was common with depression symptoms and heart disease, and 64% of the variance in heart disease was common with depression symptoms and hypertension.

CONCLUSIONS

Men who reported cardiovascular disease were significantly more likely to have depression symptoms. The lifetime co-occurrence of these phenotypes is partly explained by common genetic risk factors.

Broken heart: depression in cardiovascular disease

Heart disease and depression are among the most common diseases seen in developed countries. The relation-ship between heart disease and depression has been the subject of both popular interest and scientific research. Sadness is often portrayed as a feeling of heaviness in the chest or as a "broken heart." Interestingly as we learn more about the expression of emotions, it appears that these perceptions may simply be the language representation of somatic feelings. Large, prospective, longitudinal studies that have examined the relationship between depression and development of coronary artery disease (CAD) have shown that depression is a risk factor for the development of CAD. Depression also increases mortality in patients with stable CAD or myocardial infarction compared with patients without depression. The recent Sertraline AntiDepressant HeARt attack Trial (SADHART) has shown that selective serotonin reuptake inhibitors like sertraline can be safely used in patients with depression following myocardial infarction. There is also intriguing evidence that treating depression with antidepressants may improve outcomes, including mortality.

Are psychosocial factors associated with the pathogenesis and consequences of cardiovascular disease in the elderly?

It is well known that older individuals are at higher risk of developing cardiovascular disease (CVD). In addition, evidence exists for the relationship between psychosocial factors and the pathogenesis and cognitive consequences of CVD. However, less is known about the effect of psychosocial factors on the development and consequences of CVD in older individuals. Using a biopsychosocial framework, this article examines the influence of psychosocial factors, specifically depression, anxiety, and social isolation on older persons with CVD as well as the influence of CVD on psychosocial factors. The effectiveness of interventions for modifying adverse psychosocial factors is also discussed.

Safety of antidepressant drugs in the patient with cardiac disease: a review of the literature

Patients with cardiac disease, specifically ischemic heart disease and heart failure, have a higher frequency of major depressive disorder than patients without cardiac disease. The pathophysiologic reason for this is not completely understood. Previous depression, other debilitating illnesses, and type A personality are risk factors for the development of depression in cardiac patients. Depression has been shown to lower the threshold for ventricular arrhythmias. Therefore, treatment of depression potentially may prolong life in these patients. Antidepressant options that have been evaluated include several of the tricyclic antidepressants, trazodone, bupropion, and several of the selective serotonin reuptake inhibitors. Individual antidepressant drugs vary in their pharmacologic activity and side-effect profiles. Although clinical data are limited, it is important to individualize therapy in order to minimize cardiac adverse effects. Clinicians are encouraged to evaluate patients with cardiac disease for major depressive disorder and to consider antidepressant drug therapy for these patients when appropriate.

Platelet surface glycoprotein expression in post-stroke depression: a preliminary study

Depression is a significant risk factor for and consequence of both cardiovascular disease and stroke. The pathophysiological processes underlying this association are poorly understood. This study utilised a technique for measurement of whole blood platelet surface glycoproteins involved in early adhesion and aggregation in sample populations of patients with depression and stroke, and healthy controls. We analysed the platelet surface glycoproteins GPIb and GPIIbIIIa using flow cytometry in eight depressed subjects (Hamilton depression score >17), 14 post-stroke subjects (seven depressed and seven non-depressed), and in eight healthy control subjects. The number of GPIb receptors was significantly increased in subjects with depression and in post-stroke subjects compared to control subjects. The number of GPIb receptors from post-stroke subjects was not significantly different from that of depressed subjects. There were no differences between any groups in measures of GPIIbIIIa receptor numbers. No additive effect of co-morbid depression on the surface expression level of either marker could be detected in the post-stroke subjects. Platelet dysfunction may be involved in the pathophysiological process underlying the association between depression and cerebrovascular disease.

Depression and ischemic heart disease: overview of the evidence and treatment implications

In this article, the authors review the evidence that depression is a risk factor for ischemic heart disease and examine the efficacy and safety of depression treatments in patients with ischemic heart disease.

Does increased platelet release of Abeta peptide contribute to brain abnormalities in individuals with depression?

Increased platelet activation with release of procoagulant factors from their alpha granules has been demonstrated in individuals with major depression. Platelet activation has also been shown to be associated with release of beta-amyloid peptides, which have been implicated in Alzheimer's disease. Thus, we are hypothesizing that sustained elevations of Abeta peptides might occur in individuals with recurrent depression. We further hypothesize that such elevations contribute to brain abnormalities in depressed individuals through the formation of neurotoxic oligomeric forms of Abeta peptides and amyloid deposition. We also propose that increased amyloid Abeta peptides from platelet activation may be a mechanism underlying the increased risk for cognitive impairment in nondepressed patients who have other reasons for such activation. If true, our hypothesis would imply that platelet inhibitors may have a role in preventing or delaying the neuronal consequences of disorders characterized by activated platelets.

Depression and coronary heart disease in women with diabetes

OBJECTIVE

The protective effects of female gender on the appearance and course of coronary heart disease (CHD) in nondiabetic subjects are diminished in the presence of diabetes. Depression predicts onset of and poor outcome from CHD in nondiabetic populations. We hypothesized that the doubled rates of depression in female diabetic patients could help explain the high prevalence of CHD in women with diabetes.

METHOD

Seventy-six female type 1 and type 2 diabetic patients with (N=16) or without (N=60) active major depression (DSM-III) at index evaluation underwent systematic annual investigation of diabetes and its complications for up to 10 years. Occurrences of CHD and other macrovascular complications were examined in relation to depression status using survival analysis statistics. A multivariate model incorporating other CHD risk factors (age, duration of diabetes, body mass index, glycosylated hemoglobin, and presence of hypertension, hyperlipidemia, or tobacco use) was used to determine independent effects of depression on outcome.

RESULTS

Development of CHD was significantly more rapid in the depressed subset (p<0.01 between 10-year curves), an effect that persisted after controlling for base-line differences in body mass index. Depression also was retained as an independent predictor of CHD in the multivariate model with an age-adjusted hazard ratio of 5.2 (95% CI: 1.4-18.9; p=.01). In contrast, depression did not predict the development of clinically apparent peripheral or cerebrovascular disease.

CONCLUSIONS

In this sample of diabetic women, major depression was an independent risk factor that accelerated the development of CHD. Depression recognition and management may improve outcomes from diabetes in this gender subgroup.

Depression in patients with heart failure: physiologic effects, incidence, and relation to mortality

Heart failure affects 4.8 million people in the United States. Patients depressed after myocardial infarction have increased morbidity and mortality. Only a few studies have investigated the effects of depression in patients with heart failure. The incidence of depression in heart failure ranges from 13% to 77.5%. Men with heart failure are more likely to become depressed than the general population. Depression incidence is higher in hospitalized patients with heart failure than in stabilized outpatients. In patients with heart failure, depression is associated with mortality. Physiologic changes, which occur in depressed patients, have been implicated as possibly contributing to the increased mortality. Nurses have a major role in the management of patients with heart failure and can be pivotal in the detection and treatment of depression in these patients. Reduction in depression is likely to decrease morality in patients with heart failure.

Depression and anxiety and outcomes of coronary artery bypass surgery

Psychological and psychiatric disorders independently increase the risk of cardiovascular disease and worsen the prognosis in patients with established cardiovascular lesions. The objective of this literature review is to discuss recent data concerning the relationships between depression and anxiety and the outcomes of coronary artery bypass grafting. Pathophysiological hypotheses are put forward to explain observed links. We suggest recommendations aimed at improving the psychological evaluation and management of heart surgery candidates, as well as postbypass patients, in the hope of improving quality of life and cardiovascular outcomes in these patients.

Treatment of depression in diabetes: impact on mood and medical outcome

Depression is prevalent as a co-morbid condition in diabetes. The efficacy of depression treatment with either pharmacological agents or psychotherapy has been demonstrated in the few available controlled trials. Depression has been associated with poor glycemic control and with accelerated rates of coronary heart disease in diabetic patients. Reported depression treatment trials demonstrate benefits of depression remission on glycemic control as well as mood and the potential for improvement in the course and outcome of diabetes. Because adverse effects of pharmacological agents on glycemic control have been observed, optimal therapies that improve both depression and measures of diabetes are still being sought. This review critically examines the efficacy of depression treatment in diabetes patients, the effects of depression treatment on the medical condition, and methodological issues important in the performance of treatment trials in the patient population.

Depression as a risk factor for cardiac mortality and morbidity: a review of potential mechanisms

Depression increases the risk of cardiac mortality and morbidity in patients with coronary heart disease (CHD), but the mechanisms that underlie this association remain unclear. This review considers the evidence for several behavioral and physiological mechanisms that might explain how depression increases the risk for incident coronary disease and for subsequent cardiac morbidity and mortality. The candidate mechanisms include: (1). antidepressant cardiotoxicity; (2). association of depression with cardiac risk factors such as cigarette smoking, hypertension, diabetes, and reduced functional capacity; (3). association of depression with greater coronary disease severity; (4). nonadherence to cardiac prevention and treatment regimens; (5). lower heart rate variability (HRV) reflecting altered cardiac autonomic tone; (6). increased platelet aggregation; and (7). inflammatory processes. Despite recent advances in our understanding of these potential mechanisms, further research is needed to determine how depression increases risk for cardiac morbidity and mortality.

Platelet activation and secretion in patients with major depression, thoracic aortic atherosclerosis, or renal dialysis treatment

Relatively little is known concerning the magnitude of alterations of platelet activation and secretion markers of patients with major depression when compared to patients at increased risk for, or with current, clinically significant atherosclerosis. Markers of in vivo platelet stimulation and secretion were measured under basal conditions in normal comparison subjects (n = 12) and three patient groups: patients diagnosed with DSM-IV major depression (n = 15), dialysis-dependent patients (n = 12), and patients with severe thoracic aortic atherosclerosis (n = 10). In comparison to normal comparison subjects, depressed patients and patients with thoracic aortic atherosclerosis exhibited the greatest platelet stimulation as detected by increased anti-LIBS platelet binding. Dialysis-dependent patients exhibited the highest plasma concentrations of the renally-excreted platelet-specific secretion protein, beta-thromboglobulin. This study extends previous observations of increased platelet activation in patients with major depression and documents similar alterations in patients with transesophageal echocardiography (TEE)-documented thoracic aortic atherosclerosis. Future studies will determine whether the magnitude of platelet stimulation and secretion in patients with comorbid depression and atherosclerotic aortic disease is greater than that observed in nondepressed patients with atherosclerotic aortic disease or major depression alone. These findings provide further evidence for either increased platelet activation and/or intrinsic heightened platelet reactivity as one of the biological substrates underlying the increased risk of depressed patients for cardiovascular disease.

Depression is associated with an increase in the expression of the platelet adhesion receptor glycoprotein Ib

There is a significant association between cardiovascular disease and depression. Previous studies have documented changes in platelets in depression. It is unknown if depression causes functional changes in platelet surface receptors. Therefore, we analyzed (1) the surface expression of glycoprotein (GP)Ib and the integrin receptor alpha(IIb)beta(IIIa), receptors involved in platelet adhesion and aggregation, (2) CD62 (P-selectin) and CD63, integral granule proteins translocated during platelet activation, (3) platelet aggregation in response to ADP and (4) plasma levels of glycocalicin and von Willebrand factor (vWF), in depressed patients compared to healthy volunteers. Fifteen depressed patients with a Hamilton depression score of at least 22 and fifteen control subjects were studied. Platelets were assessed for surface expression levels of GPIb, alpha(IIb)beta(IIIa), CD62 and CD63 by flow cytometry. Genomic DNA was isolated to investigate a recently described polymorphism in the 5' untranslated region of the GPIbalpha gene. The number of GPIb receptors was significantly increased on the surface of platelets from patients with depression compared to control subjects. Surface expression of CD62 was also significantly increased in the depressed patients versus control subjects. There was no significant difference between depressed patients and healthy volunteers in the surface expression of alpha(IIb)beta(IIIa) or CD63, or in glycocalicin or vWF plasma concentration, or ADP-induced aggregation. There was no difference in allele frequency of the Kozak region polymorphism of the GPIbalpha gene, which can affect GPIb expression. The results of this study demonstrate that the number of GPIb receptors on platelets are increased in depression and suggest a novel risk factor for thrombosis in patients with depression.

Depression and heart disease: evidence of a link, and its therapeutic implications

Over several decades, a large body of evidence has emerged to suggest that depressive disorder is a risk factor for heart diseases, both aetiologically and prognostically. Several large, prospective, longitudinal studies have examined the relationship between depression and the development of coronary artery disease (CAD); they reveal that the relationship is significant and independent of conventional risk factors. Prognostic studies have shown that depression is associated with two to three times higher mortality after myocardial infarction, unstable angina or coronary artery bypass grafting, and in patients with stable CAD compared with such patients without depression. Depression also has been found to increase mortality and morbidity in patients with heart failure, regardless of its aetiology. Such adverse associations persist after adjustment for conventional prognostic risk factors. Despite all of these findings, depressed patients with heart disease are less likely to be recognised clinically as being depressed than those patients who have depression but no heart disease. The very limited evidence available from pharmacological clinical trials raises concern about the safety of antidepressants in CAD and heart failure. In addition, no research has addressed whether the treatment of depression in patients with heart disease will improve their prognosis.

Beta-thromboglobulin and platelet factor 4 levels in post-myocardial infarction patients with major depression

Platelet factor 4 (PF 4) and beta-thromboglobulin (beta-TG) were studied in 12 depressed post-myocardial infarction (MI) patients and 12 matched non-depressed post-MI patients. PF4 was significantly higher in the depressed group than in the non-depressed group. beta-TG was increased in the depressed subgroup, but the difference was not statistically significant.

Vascular basis of late-onset depressive disorder

BACKGROUND

Growing evidence suggests that there may be a subtype of depression arising in later life that is characterised by a distinct clinical presentation and an association with cerebrovascular disease. This has been termed 'vascular depression'.

AIMS

To review the evidence for associations between cardiovascular disease and depression and between cerebrovascular disease and depression, and to examine implications for clinical practice and research.

METHOD

The authors reviewed the medical literature covering the past 5 years.

RESULTS

There is strong evidence for an association between cardiovascular disease and depression, but this is not confined to older people. The causal pathway may be bi-directional. There is also a convergence of evidence suggesting a causal link between cerebrovascular disease and depression, especially that occurring later in life. The major focus has been on neuroradiological findings thought to be due to vascular disease, although the pathology may be heterogeneous.

CONCLUSIONS

Although there are gaps in the evidence there is strong support for the concept of vascular depression, characterised by reduced depression ideation, subcortical neurological dysfunction, apathy and psychomotor change. This has implications for both treatment and prevention.

Management of Depression in Patients with Comorbid Cardiovascular Disease

Evidence suggests that depression commonly occurs in patients with cardiovascular disease and is associated with a poor prognosis including increased risk of cardiac mortality. Proposed pathophysiologic mechanisms include decreased heart rate variability, altered sympathetic and parasympathetic activity, increased ventricular instability, and abnormal platelet reactivity. Other proposed mechanisms involve the interference of depression with medication adherence and cardiac risk factor reduction. Despite this evidence, depression during cardiovascular disease is commonly unrecognized and inadequately treated. Tricyclic antidepressants (TCA) are efficacious for treating depression in this population but cause serious cardiac side effects and should be avoided in patients with significant cardiovascular disease. More recent studies with bupropion and the selective serotonin reuptake inhibitors (fluoxetine, paroxetine, sertraline) indicate that they are acceptable alternatives to TCAs with regard to cardiac risk in depressed patients with heart disease, although larger studies are needed to validate their safety and efficacy in this special population. There are 3 studies currently being conducted to investigate the effect of antidepressant therapy and/or psychotherapy on cardiac morbidity and mortality in post–myocardial infarction patients with depression and/or low social support. These studies will hopefully answer the long-posed question of whether appropriate treatment of depression can improve cardiac prognosis.

Selective serotonin reuptake inhibitors and myocardial infarction

BACKGROUND

Depression is an independent risk factor for myocardial infarction (MI). Selective serotonin reuptake inhibitors (SSRIs) may reduce this risk through attenuation of serotonin-mediated platelet activation in addition to treatment of depression itself.

METHODS AND RESULTS

case-control study of first MI in smokers 30 to 65 years of age was conducted among all 68 hospitals in an 8-county area during a 28-month period. Cases were patients hospitalized with a first MI. Approximately 4 community control subjects per case were randomly selected from the same geographic area using random digit dialing. Detailed information regarding use of antidepressant medication as well as other clinical and demographic data were obtained by telephone interview. A total of 653 cases of first MI and 2990 control subjects participated. After adjustment, using multivariable logistic regression, for age, sex, race, education, exercise, quantity smoked per day, body mass index, aspirin use, family history of MI, number of physician encounters, and history of coronary disease, diabetes, hypertension, or hypercholesterolemia, the odds ratio for MI among current SSRI users compared with nonusers was 0.35 (95% CI 0.18, 0.68; P<0.01). Non-SSRI antidepressant users had a nonsignificant reduction in MI risk with wide confidence intervals (adjusted odds ratio 0.48, CI 0.17, 1.32; P=0.15). However, analysis of this group was limited by the small number of exposed subjects.

CONCLUSIONS

The use of SSRIs may confer a protective effect against MI. This could be attributable to the inhibitory effect SSRIs have on serotonin-mediated platelet activation or possibly amelioration of other factors associated with increased risk for MI in depression.

A controlled study of MRI signal hyperintensities in older depressed patients with and without hypertension

OBJECTIVES

To compare the frequency/severity of signal hyperintensities--likely markers of cerebrovascular disease--in the subcortical gray and deep white matter on magnetic resonance imaging (MRI) scans of brains of hypertensive and normotensive older depressed and nondepressed comparison subjects.

DESIGN

Between-groups comparison of cross-sectional MRI data employing analyses of covariance controlling for the effects of age, gender, and height.

SETTING

A comprehensive inpatient-outpatient geriatric psychiatry service in a university hospital.

PARTICIPANTS

Nondemented older depressed (n = 81) and nondepressed comparison (n = 70) subjects divided into four groups (hypertensive depressed (n = 40), hypertensive normals (n = 21), normotensive depressed (n = 41), normotensive normals (n = 49)).

MEASUREMENTS

Signal hyperintensities were rated on T-2 weighted MRI scans blind to patient diagnoses employing two standardized hyperintensity rating systems (Fazekas, Boyko).

RESULTS

Hypertensive depressives had significantly more- severe hyperintensity ratings in both subcortical gray and deep white matter than did normotensive depressives and controls (P < .05) and significantly more-severe hyperintensity ratings only in subcortical gray matter (P < .05) than did hypertensive controls. Hypertensive controls had significantly more-severe ratings in deep white matter than either normotensive group (P < .05).

CONCLUSIONS

Findings suggest a relationship between deep white matter hyperintensities and hypertension (regardless of depressive state), and a particular role of subcortical gray matter hyperintensities (possibly interacting with more-severe deep white matter lesions) in older depressed hypertensives, as compared with older depressed normotensives of similar ages and severity of depression. These data support possible heterogeneous pathogenic contributions in late-life depression subgroups, one of which appears to be influenced by cerebrovascular disease.

Depressive disorder, dysthymia, and risk of stroke: thirteen-year follow-up from the Baltimore epidemiologic catchment area study

BACKGROUND AND PURPOSE

This study examined depressive disorder as a risk factor for incident stroke in a prospective, population-based design.

METHODS

The Baltimore Epidemiologic Catchment Area Study is a prospective 13-year follow-up of a probability sample of household residents from Baltimore, Md. Depressive disorder was measured with the diagnostic interview schedule, and stroke was assessed by questions from the health interview survey or by documentation on a death certificate.

RESULTS

During the 13-year follow-up of 1703 individuals, 66 strokes were reported and 29 strokes were identified by death certificate search. Individuals with a history of depressive disorder were 2.6 times more likely to report stroke than those without this disorder after controlling for heart disease, hypertension, diabetes, and current and previous use of tobacco. Medications used in the treatment of depressive disorder at baseline did not alter this finding. A history of dysthymia demonstrated a similar relationship to stroke, although the estimate was not statistically significant.

CONCLUSIONS

Depressive disorder is a risk factor for stroke that appears to be independent of traditional cardiovascular risk factors. Further research on mechanisms for the association and the impact of treatment for depressive disorder on subsequent stroke is needed.

Increased platelet aggregability in major depression?

There is compelling evidence that depression constitutes an independent risk factor for cardiovascular morbidity and mortality. As exaggerated platelet reactivity is associated with an increased risk of intra-arterial thrombus formation, we studied platelet aggregability in patients with major depression both before and after 5 weeks of anti-depressant therapy as well as in healthy control subjects. Twenty-two depressed patients and 24 healthy control subjects participated in the study. Washed and rediluted platelets were stimulated with the agonists collagen and thrombin in three concentration steps. Depression was associated with a higher aggregability after stimulation with thrombin in the intermediate concentration and with collagen at the low concentration, with ceiling effects for the other concentrations. After 5 weeks of anti-depressant therapy, aggregability was somewhat less exaggerated, although this effect did not reach statistical significance. We thus conclude that major depression is associated with increased platelet aggregability, which seems to persist even under a marked improvement in depressive symptomatology. This effect may contribute to the increased cardiovascular morbidity in depressed patients.

Depressed mood, physician-rated prognosis, and comorbidity as independent predictors of 1-year mortality in consecutive medical inpatients

OBJECTIVE

To determine the independent effects of depressed mood and markers of medical disease severity on mortality in consecutive medical inpatients.

METHODS

Consecutive general medical inpatients were asked to complete the Hospital Anxiety and Depression Scale (HADS) at admission. Prognostic indicators were obtained from patients' records and physicians' ratings. The study endpoint was mortality from all causes at 1 year.

RESULTS

The baseline assessment was completed by 575 patients (87.7%). Survival data were available for 572 of these (86 deaths). HADS depression scores and several physical risk indicators predicted mortality. In multivariate analyses, physicians' rating of prognosis was the best predictor of mortality [adjusted odds ratio (OR) 3.6; 95% confidence interval (CI), 2.5--5.4]. Other independent predictors included a principal diagnosis of hemato-oncological disease, comorbidity scores, and HADS depression (adjusted OR 1.75; 95% CI, 1.10--2.79).

CONCLUSION

Our data demonstrate an independent prognostic effect of depressed mood on mortality in general medical inpatients. Screening for depression may improve risk stratification in these patients over and above that obtained by routinely available physical parameters and physicians' clinical judgement.

Hopelessness predicts mortality in older Mexican and European Americans

OBJECTIVE

The purpose of this study was to evaluate the relationship between hopelessness and mortality in a biethnic cohort of older community-dwelling Mexican Americans, the most rapidly growing segment of the elderly, and European Americans.

METHODS

A total of 795 persons aged 64 to 79 years completed an English or Spanish version of the 30-item Geriatric Depression Scale on entering the San Antonio Longitudinal Study of Aging, an epidemiologic survey, between 1992 and 1996. Women constituted 58% and Mexican Americans 54% of this randomly selected sample. Subjects who answered "no" to the item "Are you hopeful about the future?" were classified as hopeless.

RESULTS

As of August 1999, 29% of the 73 hopeless subjects had died, compared with 11% of the hopeful, a highly significant difference. The mortality rates for cardiovascular disease and cancer were significantly greater among the hopeless subjects (7%) than among the hopeful (3%). Hopelessness predicted all-cause mortality in a Cox proportional hazards model adjusted for age, ethnic background, current smoking status, number of comorbid medical conditions, self-rated health, and frequency of social contacts (risk ratio = 2.23, 95% confidence interval = 1.33 to 3.76, p = .0026). Neither sex nor probable depression was a significant predictor of mortality in this model.

CONCLUSION

These findings, together with those of others, suggest that hopelessness is a significant predictor of mortality in older and middle-aged adults of various ethnic backgrounds. Further research is needed to evaluate the mechanisms that underlie this phenomenon and the effects of treating hopelessness on the quality and duration of subjects' lives.

Depression but not anxiety influences the autonomic control of heart rate after myocardial infarction

AIMS

It has been previously hypothesized that the adverse outcome observed in depressed patients after myocardial infarction might be due to an imbalance in autonomic nervous system activity. The aim of this study was to define the role of depressive and anxious symptoms in influencing autonomic control of heart rate after myocardial infarction.

METHODS AND RESULTS

The SD of RR intervals, baroreflex sensitivity, and depression and anxiety (Zung's scales) were assessed before discharge in 103 patients with acute myocardial infarction; 32 were found to be depressed. Among the patients who were not taking beta-blockers, those with depression had significantly lower SDs of RR intervals and baroreflex sensitivity than did those without depression (96.3 +/- 22.2 ms vs 119.5 +/- 37.7 ms, P =.016; 8.6 +/- 6.2 ms vs 11.8 +/- 6.5 ms/mm Hg, P =.01, respectively). No differences were found when anxiety was considered or when beta-blockers were given. Among the patients not taking beta-blockers, there was a significant correlation between depression levels and both the SD of RR intervals (r = -0.47) and baroreflex sensitivity (r = -0.40).

CONCLUSIONS

In patients with myocardial infarction, depression but not anxiety negatively influences autonomic control of heart rate. Beta-blockers modify these influences.