A case report—“When less is more”: controlled inpatient reduction of anticholinergic burden in a patient with clozapine-resistant schizophrenia

Antipsychotics are effective in preventing relapses of schizophrenia, but it is generally believed that their long‐term use is harmful for patients’ physical well‐being. However, there are no long‐term studies which have verified this view. This nationwide, register‐based cohort study aimed to assess the risk of hospitalization due to physical health problems, as a marker for severe physical morbidity, and the risk of all‐cause mortality, as well as of cardiovascular and suicidal death, associated with antipsychotic use in all patients treated for schizophrenia in inpatient care between 1972 and 2014 in Finland (N=62,250), with up to 20 years of follow‐up (median: 14.1 years). The use of antipsychotic drugs (i.e., use of any antipsychotic compared with non‐use) and the use of specific antipsychotics were investigated, and outcomes were somatic and cardiovascular hospitalization, and all‐cause, cardiovascular and suicide death. Hospitalization‐based outcomes were analyzed by a within‐individual design to eliminate selection bias, comparing use and non‐use periods in the same individual by stratified Cox model. Mortality outcomes were assessed by traditional between‐individual Cox multivariate models. The adjusted hazard ratios (aHRs) for any somatic hospitalization and cardiovascular hospitalization were 1.00 (95% CI: 0.98‐1.03) and 1.00 (95% CI: 0.92‐1.07) during use of any antipsychotic compared to non‐exposure periods within the same individual. The aHRs were 0.48 (95% CI: 0.46‐0.51) for all‐cause mortality, 0.62 (95% CI: 0.57‐0.67) for cardiovascular mortality, and 0.52 (95% CI: 0.43‐0.62) for suicide mortality during use vs. non‐use of any antipsychotic. The most beneficial mortality outcome was associated with use of clozapine in terms of all‐cause (aHR=0.39, 95% CI: 0.36‐0.43), cardiovascular (aHR=0.55, 95% CI: 0.47‐0.64) and suicide mortality (aHR=0.21, 95% CI: 0.15‐0.29). The cumulative mortality rates during maximum follow‐up of 20 years were 46.2% for no antipsychotic use, 25.7% for any antipsychotic use, and 15.6% for clozapine use. These data suggest that long‐term antipsychotic use does not increase severe physical morbidity leading to hospitalization, and is associated with substantially decreased mortality, especially among patients treated with clozapine.

Deficits in cholinergic function have been postulated to cause delirium and cognitive decline. This review examines current understanding of the cholinergic deficiency hypothesis in delirium by synthesizing evidence on potential pathophysiological pathways. Acetylcholine synthesis involves various precursors, enzymes, and receptors, and dysfunction in these components can lead to delirium. Insults to the brain, like ischemia and immunological stressors, can precipitously alter acetylcholine levels. Imbalances between cholinergic and other neurotransmitter pathways may result in delirium. Furthermore, genetic, enzymatic, and immunological overlaps exist between delirium and dementia related to the cholinergic pathway. Important areas for future research include identifying biomarkers, determining genetic contributions, and evaluating response to cholinergic drugs in delirium. Understanding how the cholinergic pathway relates to delirium may yield innovative approaches in the diagnosis, prevention, and treatment of this common, costly, and morbid condition.

Clozapine is the most effective antipsychotic for the 25% to 33% of people with schizophrenia who are treatment resistant, but not all people achieve response. Using data from a previously published clozapine systematic review and meta-analysis, we explored the proportion of people who achieved response and examined the absolute and percentage change in Positive and Negative Syndrome Scale (PANSS) scores. Overall, 40.1% (95% confidence interval [CI], 36.8%-43.4%) responded, with a mean reduction in PANSS of 22.0 points (95% CI, 20.9-23.1), a reduction of 25.8% (95% CI, 24.7%-26.9%) from baseline. These reductions are clinically meaningful. A 40% response rate to clozapine suggests that 12% to 20% of people with schizophrenia will be ultra-resistant. La clozapine est l’antipsychotique le plus efficace pour les 25 à 33% des personnes souffrant de schizophrénie qui sont réfractaires au traitement; toutefois, les personnes n’obtiennent pas toutes une réponse. À l’aide des données d’une revue systématique et d’une méta-analyse publiées précédemment, nous avons exploré la proportion de gens qui obtenaient une réponse, et examiné le pourcentage absolu et les changements de pourcentage dans les scores à l’échelle des syndromes positifs et négatifs (PANSS). Globalement, 40,1% (IC à 95% 36,8% à 43,4%) ont répondu, avec une réduction moyenne à la PANSS de 22,0 points (IC à 95% 20,9 à 23,1), une réduction de 25,8% (IC à 95% 24,7% à 26,9%) par rapport au départ. Ces réductions sont cliniquement significatives. Un taux de réponse de 40% à la clozapine suggère que de 12% à 20% des personnes souffrant de schizophrénie seront ultra-réfractaires.