Roland Dardennes

Role of the ghrelin/obestatin balance in the regulation of neuroendocrine circuits controlling body composition and energy homeostasis.

Ghrelin and obestatin are two peptides isolated from the gastrointestinal tract and encoded by the same preproghrelin gene. They convey to the central nervous system informations concerning the nutritional status and/or the energy stores. Ghrelin, mostly acting through the GH secretagogue receptor GHS-R, is a potent GH secretagogue, an orexigenic peptide and a long-term regulator of energy homeostasis. Obestatin was initially described for its anorexigenic effects and its binding to the G protein-coupled receptor 39 (GPR39). However, the role of obestatin is still controversial and the nature of the obestatin receptor remains an open question. This review is focussed on the possible implication of the ghrelin/obestatin system in psychiatric diseases with particular emphasis on eating disorders.

Why do people with eating disorders drop out from inpatient treatment?: the role of personality factors.

Abstract Dropout rates from inpatient treatment for eating disorders are very high and have a negative impact on outcome. The purpose of this study was to identify personality factors predictive of dropout from hospitalization. A total of 64 adult patients with anorexia nervosa consecutively hospitalized in a specialized unit were included; 19 patients dropped out. The dropout group and the completer group were compared for demographic variables, clinical features, personality dimensions, and personality disorders. There was no link between clinical features and dropout, and among demographic variables, only age was associated with dropout. Personality factors, comorbidity with a personality disorder and Self-transcendence dimension, were statistically predictive of premature termination of hospitalization. In a multivariate model, these two factors remain significant. Personality traits (Temperament and Character Inventory personality dimension and comorbid personality disorder) are significantly associated with dropout from inpatient treatment for anorexia nervosa. Implications for clinical practice, to diminish the dropout rate, will be discussed.

Successful augmentation of clozapine-resistant treatment of schizophrenia with clonidine

Clozapine is considered the reference for antipsychotic agent because of its superior clinical efficacy in treatment-resistant schizophrenia. Nevertheless, 40% to 70% of neuroleptic-resistant schizophrenic patients are nonresponders to clozapine (Kane et al., 1988; Tollefson et al., 2001). Several clozapine augmentation strategies have come into clinical practice although often without evidence-based support (Mouaffak et al., 2006). It has been proposed that a relatively potent blockade of 5-HT(2A) receptors coupled with the weaker antagonism of the dopamine D(2) receptors may play a critical role in the mechanism of action of atypical antipsychotic drugs such as clozapine (Meltzer and Huang, 2008). Litman et al. (1996) also suggested that the antagonism of α2adrenergic receptors by clozapine may contribute to its superior effects. Meanwhile, Lechin et al. (1980) successfully used clonidine, an α2-adrenergic receptor agonist which decreases noradrenergic neuron firing and release through presynaptic action (Arnsten, 2004), to treat a subset of patients with residual schizophrenia who relapsed after withdrawal of their usual treatment; Lerner et al. (1998) also used clonidine to treat the hallucinatory «flashbacks» experienced by former users of LSD. Thus, we successfully added clonidine in a case of resistance to clozapine.