Hepatitis B vaccination in haemodialysis patients: an underestimated problem. Factors influencing immune responses in ten years of observation in an Italian haemodialysis centre and literature review.

OBJECTIVES: Despite universal infection control precautions, the risk of hepatitis B virus (HBV) infection in patients on chronic haemodialysis (HD) remains high. For this reason anti-HBV vaccination is recommended in these subjects. In hemodialyzed patients vaccinal response is often suboptimal and it's not clear what factors may influence it. STUDY DESIGN: The aim of our study is to assess the influence of some clinical and laboratory factors on seroconversion rate after anti HBV vaccination in a cohort of patients on maintenance HD. METHODS: We analysed 60 patients on regular HD, 40 men and 20 women (age 64±12 years, range 40-88 years), immunized with Engerix B ® vaccine, followed for an average time of 62 month (12-120 months). For each patient the following data were collected: age, serum albumin (sAlb), Blood urea nitrogen before HD session (BUN), age at vaccination, dialysis vintage, presence of systemic disease, type of vascular access, dialysis modality. Correlation between these factors and anti Hbs titer was estimated with multiple regression analysis. RESULTS: Anti-Hbs seroconversion rate ( Anti Hbs > 10 IU/l) was 77%. Better rate of seroconversion (86%) was observed in patients with arteriovenous fistula (AVF) and serum albumin > 3,5 g/dL (93%), while higher rate of not responders (50%) in patients with systemic diseases. The only parameter correlated to anti Hbs titer was sAlb (p =0,0012). sAlb was correlated to age in all patients (p=0,01) and age was correlated to higher anti Hbs titer in the responder group (p=0,018). DISCUSSION: In our experience an early vaccination, when patients on chronic HD are younger and in better nutritional conditions, improves anti-HBV response.

Harm aversion explains utilitarian choices in moral decision-making in males but not in females.

In recent years, a great deal of research has relied on hypothetical sacrificial dilemmas to investigate decision-making processes involved in pro-social utilitarian choices. Recent evidence, however, has suggested that moral sacrificial choices may actually reflect reduced harm aversion and antisocial dispositions rather than an utilitarian inclination. Here, we used moral dilemmas to confront healthy volunteers with controversial action choices. We measured impulsiveness and venturesomeness personality traits, which have been shown to influence harm aversion, to test their role in utilitarian action and evaluation of moral acceptability. The results of the present study show that, in males, venturesomeness drives engagement in actions and increases moral acceptability. In contrast, in females no effects of venturesomeness were observed on moral action and evaluation. Rather, in females empathetic concern and personal distress, elicited by the vicarious experience of the other's emotional states, exerted an inhibitory effect on action. Taken together, these findings indicate that the "harm aversion hypothesis" may contribute to explain utilitarian choices in males but not in females. In both genders, no association was observed between impulsiveness and moral action.

Nighttime cardiac sympathetic hyper-activation in young primary insomniacs.

PURPOSE: A growing literature supports the association between insomnia and cardiovascular risk. Since only few studies have provided empirical evidence of hyper-activation of the cardiovascular system in insomniacs, the aim of the present study was to analyze cardiac autonomic responses in primary insomnia. METHODS: Impedance cardiography and heart rate variability (HRV) measures were assessed in 9 insomniacs and 9 good sleepers during a night of polysomnographic recording. RESULTS: Insomniacs were found to be characterized by a constant sympathetic hyper-activation which was maintained all night, as suggested by a faster pre-ejection period (PEP) compared to good sleepers. In addition, only insomniacs showed a strong reduction in heart rate in the transition from wake to sleep. Both groups exhibited a reduction in cardiac output and sympathovagal balance, i.e., reductions in low-frequency/high-frequency ratio and increases in high-frequency normalized units of HRV, across the night. In addition, in our sample, a high physiological sympathetic activation (fast PEP) at night was found to be directly associated with low quality of sleep. CONCLUSIONS: These preliminary findings suggest that a constant cardiac sympathetic hyper-activation throughout the night is a main feature of primary insomnia. Our evidences support the association between insomnia and increased risk for cardiovascular diseases.

Cardiac responses associated with affective processing of unpleasant film stimuli.

The autonomic basis of cardiac reactions to unpleasant film stimuli was investigated. Film clips depicting major surgery, threats of violence, and neutral material were presented to 46 subjects. Self-report measures of emotion were obtained, as well as heart rate, respiration rate, respiratory sinus arrhythmia, T-wave amplitude and skin conductance level. Resting vagal tone was estimated in a paced breathing task prior to film viewing. Spontaneous blink rate was also taken as a measure of visual engagement during film viewing. Coherent increases in sympathetic activation accompanied the film containing violent threats, whereas the surgery film yielded greater electrodermal activation, as well as heart rate deceleration and T-wave increase. These data support the hypothesis of differential autonomic response patterns to specifically unpleasant material. As compared with threat and neutral films, greater blink rate inhibition was observed during the surgery film. Individual differences in parasympathetic cardiac control measured at rest were able to discriminate cardiac response patterns during film viewing.

Respiratory sinus arrhythmia in blood phobic subjects.

12 blood-phobic subjects, selected according to the Fear Survey Schedule and the Mutilation Questionnaire, and 50 control subjects performed a paced respiration task during which heart rate and respiration were recorded. Respiratory Sinus Arrhythmia (RSA) was analyzed as an autonomic index of vagal influence on the heart. Analysis showed a larger RSA in the blood-phobic group than the controls and points to a difference in vagal activity at rest between the groups.

The time course of implicit processing of facial features: an event-related potential study.

In this study, we used ERPs to investigate the time course of implicit face processing. More specifically, we utilized a masked priming paradigm to investigate implicit processing of the eyes and mouth in upright and inverted faces, using a prime duration of 33ms. Two types of prime-target pairs were used: (1) congruent (e.g., open eyes only in both prime and target); (2) incongruent (e.g., open eyes only in prime and open mouth only in target). The identity of the faces changed between prime and target. Participants pressed one button to indicate whether the target face's mouth was open, and another if the eyes were open. The behavioral results indicated a congruent priming effect for upright but not for inverted faces. The ERP results indicated a face orientation effect across all ERP components studied (P1, N1, P2, N170, N2, P3) starting at about 80ms, and a congruency/priming effect on late components (N2, P3), starting at about 200ms. The functional significance of these ERP effects is discussed in relation to unconscious perception and configural face processing.

Auditory event-related potentials and reaction times in migraine children.

Cognitive processing was investigated interictally in 18 children with migraine without aura and 18 age-matched controls by measuring event-related potentials (ERPs) and reaction times (RTs) during an acoustic oddball paradigm. Results showed that N100 amplitude evoked by frequent stimuli was significantly smaller in patients compared with controls. Habituation of target P300 amplitude was observed in patients but not in controls. Mean RTs were equivalent in the two groups, but migraine children made more errors than controls.