Tuesday, 9 July 2013

Psychotic Phenotypes and Autonomous Action

Alessandro Blasimme 
& Marco Canevelli

The relationship between mental capacities and autonomy has long been a matter of dispute, but we can surmise that clinical judgments about one’s mental capacities may incorporate or support considerations about patients’ autonomy as well as value judgments bearing on the choice of different therapeutic options, on how and to which degree a patient should be involved in therapeutic decisions and, finally, on the role of caregivers. This has important consequences for patients affected by dementia.

Behavioural and psychological symptoms of dementia (BPSD) are defined as “a heterogeneous set of psychological reactions, psychiatric symptoms and anomalous behaviours that appear in patients with dementia, of any etiology” (Finkel et al. 1996).

BPSD represent common clinical features of the dementia syndrome. Moreover, as they are, associated with several adverse outcomes (e.g. worse quality of life, functional impairment, greater caregiver’s burden, and higher hospitalization rates) they are extremely burdening for the patient, families, caregivers, and public health systems. Despite sharing these common characteristics, the neuropsychiatric manifestations of dementias are characterized by a marked inter-individual variability. 

One of us (Marco) has recently performed a systematic review of studies defining neuropsychiatric phenotypes in patients affected by Alzheimer’s Disease (AD) by adopting factor analysis of the Neuropsychiatric Inventory (NPI), the most widely adopted and recommended clinical tool for the assessment of BPSD (the analysis finally accounted for more than 7.500 AD patients - Canevelli et al. 2012). This analysis isolated a “psychotic” cluster/phenotype, characterized by hallucinations and delusions. Interestingly, these symptoms are reported to occur always in combination: such psychotic cluster may thus be considered as a potential distinct phenotype of AD. Delusions and hallucinations are commonly observed during the course of the disease.  
Delusions are typically paranoid type, non-bizarre, and simple (e.g. persecution, infidelity, abandonment, and the belief that deceased individuals are still alive). Complex or bizarre delusions seen in patients with schizophrenia are conspicuously absent in patients with AD. Misidentification phenomena (e.g. the belief that there are phantom boarders in the house, that ones’ spouse is an imposter, or that ones’ home is not really one’s own), however, are common in AD. Hallucinations are more frequently visual than auditory. Those psychotic symptoms are associated with a relevant distress for patients, familiars, and caregivers. 

University of Toulouse (France)
Faculty of Medicine
When we met in Toulouse we started to think about at the implications of such psychotic phenotype on the ascription of autonomous actions to AD patients. In particular, we want to analyse whether and under which circumstances BPSDs could be valid indicators of a patient’s incapacity to perform autonomous actions that are relevant in the clinical context, such as consenting to and refusing therapy or enrolment in research. Moreover, the autonomy of clinically relevant actions in BPSD-affected AD patients can be influenced by both the psychotic phenotype itself and by the stance of physicians and caregivers. 

This has obvious consequences on the normative obligations of physicians and caregivers towards AD patients because, just as certain specific clinical attitudes incorporate assumptions about their capacity for autonomy, others may turn out to be effective in enabling autonomous choice in individuals belonging to a class of patients generally not considered as substantially autonomous actors.
[by Alessandro Blasimme & Marco Canevelli]

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