Observational studies using health administrative data have the potential to drive evidence-based palliative care practice and policy. Further development of quality care markers will enhance benchmarking activities across health care jurisdictions, providers, and patient populations.

Reward detection, surprise detection and prediction-error signaling have all been proposed as roles for the ventral striatum (vStr). Previous neuroimaging studies of striatal function in schizophrenia have found attenuated neural responses to reward-related prediction errors; however, as prediction errors represent a discrepancy in mesolimbic neural activity between expected and actual events, it is critical to examine responses to both expected and unexpected rewards (URs) in conjunction with expected and UR omissions in order to clarify the nature of ventral striatal dysfunction in schizophrenia. In the present study, healthy adults and people with schizophrenia were tested with a reward-related prediction-error task during functional magnetic resonance imaging to determine whether schizophrenia is associated with altered neural responses in the vStr to rewards, surprise prediction errors or all three factors. In healthy adults, we found neural responses in the vStr were correlated more specifically with prediction errors than to surprising events or reward stimuli alone. People with schizophrenia did not display the normal differential activation between expected and URs, which was partially due to exaggerated ventral striatal responses to expected rewards (right vStr) but also included blunted responses to unexpected outcomes (left vStr). This finding shows that neural responses, which typically are elicited by surprise, can also occur to well-predicted events in schizophrenia and identifies aberrant activity in the vStr as a key node of dysfunction in the neural circuitry used to differentiate expected and unexpected feedback in schizophrenia.

Recent findings reveal qualitative developmental differences in extinction of learned fear. The present study explored potential developmental differences in the role of NMDA in acquisition and extinction. Rats were injected with MK-801 prior to fear conditioning or extinction training. Acquisition was found to be NMDA dependent in both age groups, whereas extinction was found to be NMDA dependent in 23-day-old rats, but NMDA independent in 16-day-old rats. These results illustrate another fundamental developmental difference in extinction as well as a dissociation in the role of NMDA in the acquisition and extinction of fear early in development.The acquisition of fear is commonly studied with Pavlovian conditioning procedures in which a neutral conditioned stimulus (CS; e.g., tone) is paired with an aversive unconditioned stimulus (US; e.g., footshock). Subsequent presentations of the CS elicit a number of fear responses (e.g., freezing), but these reactions can be extinguished by repeatedly presenting the CS in the absence of the US. Previous research shows that both the acquisition and extinction of learned fear involves N-methyl-D-aspartate (NMDA) receptors. Specifically, infusing APV (a selective NMDA antagonist) into the amygdala impairs acquisition of fear conditioning (Miserendino et al. 1990) and extinction (Falls et al. 1992). Baker and Azorlosa (1996) also found that NMDA antagonists impair long-term extinction by giving systemic injections of MK-801.While NMDA is involved in both the acquisition and extinction of learned fear in adult rats, the role of NMDA in these processes has not been systematically examined during development. Further, recent studies suggest that the mechanisms underlying extinction are qualitatively different during development. More specifically, renewal and reinstatement are observed in adult rats (see Bouton 2002) and postnatal day (PND) 23 rats; however, neither occur in PND 16 rats (Kim and Richardson 2007a,b;Yap and Richardson 2007). Likewise, pre-test administration of the GABA inverse agonist FG-7142 results in a return of conditioned responding after extinction training in PND 23 (Kim and Richardson 2007a) and adult rats (Harris and Westbrook 1998), but not in PND 16 rats. Taken together, these findings provide support for the idea that the processes mediating extinction are not uniform across development.This study explored developmental differences in the role of NMDA in the acquisition and extinction of learned fear. Specifically, the effect of the NMDA receptor antagonist MK-801 on fear conditioning and extinction was examined in PND 16 and PND 23 rats. In each experiment, the group label refers to the age at which fear conditioning occurred.The fear conditioning and extinction procedures used in the current study were the same as previous studies from our laboratory (see Kim and Richardson 2007a for details). MK-801 (Sigma-Aldrich) or saline was administered subcutaneously at a volume of 2 mL/kg. First, we examined whether there are age-related differences in th...

BackgroundThere is limited population-level research on end-of-life care in Australia that considers health care use and costs across hospital and community sectors. The aim of this study was to quantify health care use and costs in the last 6 months of life in a cohort of elderly Australian decedents and to examine the factors associated with end-of-life resource use and costs.MethodsA retrospective cohort study using routinely collected health data from Australian Government Department of Veterans’ Affairs clients. The study included two cohorts of elderly Australians who died between 2005 and 2009; one cohort with a recorded cancer diagnosis and a comparison cohort with no evidence of a cancer history. We examined hospitalisations, emergency department (ED) visits, prescription drugs, clinician visits, pathology, and procedures and associated costs in the last 6 months of life. We used negative binominal regression to explore factors associated with health service use and costs.ResultsThe cancer cohort had significantly higher rates of health service use and 27% higher total health care costs than the comparison cohort; in both cohorts, costs were driven primarily by hospitalisations. Older age was associated with lower costs and those who died in residential aged care incurred half the costs of those who died in hospital.ConclusionsThe results suggest differences in end-of-life care pathways dependent on patient factors, with younger, community-dwelling patients and those with a history of cancer incurring significantly greater costs. There is a need to examine whether the investment in end-of-life care meets patient and societal needs.Electronic supplementary materialThe online version of this article (doi:10.1186/s12904-017-0213-0) contains supplementary material, which is available to authorized users.