Impact of psychological factors on the pathogenesis of cardiovascular disease and implications for therapy. (9/807)

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.  (+info)

The association of body mass index with social and economic disadvantage in women and men. (10/807)

BACKGROUND: Although an inverse relationship between socioeconomic status and body mass index (BMI) is well documented, broad population studies focusing on the association between BMI and various forms of disadvantage such as unemployment, low income or social isolation are rare. METHODS: A nationwide, representative sample of 25-64-year-old Finnish subjects (n = 6016) was classified according to their BMI into four groups: 'thin' (BMI < 20), 'normal' (BMI 20-24.9), 'overweight' (BMI 25-29.9) and 'obese' (BMI > or = 30). Multivariable analyses using logistic regression were conducted with this BMI-grouping as an independent variable to predict social and economic disadvantage, controlling simultaneously for age, educational attainment, region of residence, and limiting long-standing illness. RESULTS: In women, overweight was associated with current unemployment and obesity with long-term unemployment as well as absence of close friends outside the family circle. Both overweight and obesity were associated with low individual earnings. Obese women were also most likely to have low household disposable and individual incomes; a similar pattern was seen among thin women. A small subgroup of thin men were socially and economically disadvantaged with all our indicators whereas excess body weight was not problematic for men. CONCLUSIONS: Deviant body weight is associated with social and economic disadvantage in a gender-specific and partly curvilinear way. In particular, obese women face multiple social and economic disadvantage.  (+info)

Risk of admission within 4 weeks of discharge of elderly patients from the emergency department--the DEED study. Discharge of elderly from emergency department. (11/807)

OBJECTIVE: to identify risk factors for admission for patients aged 75 years and older after discharge from the emergency department (DEED: discharge of elderly from emergency department). DESIGN: Prospective evaluation of discharged elderly patients from the emergency department who were followed up after 4 weeks. SETTING: emergency department of a teaching hospital for 1 year. SUBJECTS: patients aged 75 and over discharged to their home or hostel. MAIN OUTCOME MEASURES: demographic data, indices of function and cognitive status and admission to hospital within 4 weeks. RESULTS: 468 patients aged 75 and over (mean age 81.7 years; range 75-98) were enrolled; 80 patients (17.1%) were admitted to hospital during the subsequent 4 weeks. Risk factors for admission included dependence in the following activities of daily living (relative risk; 95% confidence interval): bathing (2.41; 1.32-4.41); dressing (2.38; 1.22-4.63); stairs (1.60; 1.09-2.33); finance (1.66; 1.23-2.25); shopping (1.39; 1.12-1.73) and transport (1.61; 1.25-2.06), as well as use of a community nurse (1.88; 1.12-3.17). Logistic regression analysis found two variables to be significant in predicting admission or not: dependence in transport and use of a community nurse. CONCLUSIONS: older patients are at increased risk of readmission within 4 weeks of being sent home from the emergency department. It is possible to identify high-risk patients by a questionnaire. This allows targeting of these patients for more intensive follow-up in an attempt to ameliorate further deteriorations in their health.  (+info)

Effects of LU-111995 in three models of disrupted prepulse inhibition in rats. (12/807)

LU-111995 is a novel antipsychotic drug in clinical development. It has a clozapine-like receptor profile and affinities for dopamine D(4) and 5-hydroxytryptamine(2A) receptors. The effects of LU-111995 were examined in three models of disrupted prepulse inhibition (PPI) in rats. The first model tested the hypothesis that LU-111995 would normalize the deficit in PPI exhibited by rats treated with the dopamine agonist apomorphine. LU-111995 significantly reduced the effect of apomorphine on PPI but also slightly increased PPI by itself. Thus, the increases in PPI were not specific to the animals treated with apomorphine but reflected an effect of LU-111995 on PPI. LU-111995 also attenuated the apomorphine-induced increase in startle reactivity. The second model tested the hypothesis that LU-111995 would normalize the deficit in PPI exhibited by rats treated with the psychotomimetic phencyclidine (PCP). LU-111995 significantly blocked the PCP-induced increase in startle reactivity but did not alter the PPI-disruptive effects of PCP. The third model tested the hypothesis that LU-111995 would normalize the deficit in PPI exhibited by isolation-reared rats tested as adults. Isolation rearing of rats produced deficits in PPI. LU-111995 reversed the isolation rearing-induced deficit in PPI without having any significant effect on PPI in socially reared rats. In summary, LU-111995 exhibits potential antipsychotic-like activity in two models of disrupted PPI. It remains to be elucidated whether its effects on PPI can be attributed to a blockade of single dopamine and 5-hydroxytryptamine receptor subtypes, especially D(4) and 5-hydroxytryptamine(2A), or a combination of both.  (+info)

Genetic elimination of known pheromones reveals the fundamental chemical bases of mating and isolation in Drosophila. (13/807)

Overexpression of the UAS-tra transgene in Drosophila melanogaster females led to the complete elimination of their cuticular pheromones. According to current models of Drosophila behavior, these flies should induce no courtship. In fact, they are still attractive to conspecific males. Three classes of stimuli are shown to induce courtship, with different effects on male behavior: (i) known pheromones produced by control females, (ii) stimuli produced by living control and transgenic flies, and (iii) as-yet-undetermined pheromones present on both control and transgenic flies. Only the latter class of pheromones are required for mating. They appear to represent a layer of ancestral attractive substances present in D. melanogaster and its sibling species; known cuticular pheromones modulate this attractivity positively or negatively. The absence of inhibitory pheromones leads to high levels of interspecific mating, suggesting an important role for these cuticular hydrocarbons in isolation between species.  (+info)

Experience-expectant plasticity in the mushroom bodies of the honeybee. (14/807)

Worker honeybees (Apis mellifera) were reared in social isolation in complete darkness to assess the effects of experience on growth of the neuropil of the mushroom bodies (MBs) during adult life. Comparison of the volume of the MBs of 1-day-old and 7-day-old bees showed that a significant increase in volume in the MB neuropil occurred during the first week of life in bees reared under these highly deprived conditions. All regions of the MB neuropil experienced a significant increase in volume with the exception of the basal ring. Measurement of titers of juvenile hormone JH) in a subset of bees indicated that, as in previous studies, these rearing conditions induced in some bees the endocrine state of high JH associated with foraging, but there was no correlation between JH titer and volume of MB neuropil. Treatment of another subset of dark-reared bees with the JH analog, methoprene, also had no effect of the growth of the MB neuropil. These results demonstrate that there is a phase of MB neuropil growth early in the adult life of bees that occurs independent of light or any form of social interaction. Together with previous findings showing that an increase in MB neuropil volume begins around the time that orientation flights occur and then continues throughout the phase of life devoted to foraging, these results suggest that growth of the MB neuropil in adult bees may have both experience-expectant and experience-dependent components.  (+info)

Exploring the effect of depression on physical disability: longitudinal evidence from the established populations for epidemiologic studies of the elderly. (15/807)

OBJECTIVES: This study examined the effect of depression on the incidence of physical disability and the role of confounding and explanatory variables in this relationship. METHODS: A cohort of 6247 subjects 65 years and older who were initially free of disability was followed up for 6 years. Baseline depression was assessed by the Center for Epidemiological Studies Depression Scale. Disability in mobility and disability in activities of daily living were measured annually. RESULTS: Compared with the 5751 nondepressed subjects, the 496 depressed subjects had a relative risk (95% confidence interval) of 1.67 (1.44, 1.95) and 1.73 (1.54, 1.94) for incident disability in activities of daily living and mobility, respectively. Adjustment for sociodemographic characteristics and baseline chronic conditions reduced the risks to 1.39 (1.18, 1.63) and 1.45 (1.29, 1.93), respectively. Less physical activity and fewer social contacts among depressed persons further explained part of their increased disability risk. CONCLUSIONS: Depression in older persons may increase the risk for incident disability. This excess risk is partly explained by depressed persons' decreased physical activity and social interaction. The role of other factors (e.g., biological mechanisms) should be examined.  (+info)

Online social support for individuals concerned with heart disease: observing gender differences. (16/807)

Using a theoretical framework of social support, and content analysis, the content and pattern of support in messages posted in a 4-week period on a commercial health network for individuals concerned with heart disease were observed and described. Special consideration was given to identifying gender differences.  (+info)