“The use of antipsychotics (…) in adults with dementia is associated with increased risks of stroke, venous thromboembolism, myocardial infarction, heart failure, fracture, pneumonia and acute renal failure,” lists this study published in the British Medical Journal (BMJ).
These treatments – risperidone, haloperidol, quetiapine and olanzapine – are normally used for psychotic disorders such as schizophrenia. They are also sometimes used against depression that is particularly resistant to other medications.
But it also happens that they are prescribed to patients suffering from dementia, such as Alzheimer’s. It is not a question of curing these illnesses, most of the time incurable, but of calming certain symptoms such as aggressive behavior.
Alzheimer’s disease: the promise of immunotherapy
When Alzheimer’s disease occurs, the brain undergoes different types of damage. Among them, the abnormal accumulation outside nerve cells of a protein called ß-amyloid peptide leading to the formation of plaques. The latter “are deposited between the nerve cells located in the gray matter of the cerebral cortex, causing a dysfunction of the connections between the neurons”, specifies the Alzheimer Research Foundation.
Controversial use
This use is, however, very controversial, due to the serious side effects that these treatments pose a risk of, and their limited effectiveness in this indication.
In France, as in the United Kingdom, where the BMJ study was carried out, only risperidone and haloperidol are authorized for dementia.
The BMJ study shows even broader risks of antipsychotics used in dementia than previously considered, including for example pneumonia.
Resumption of prescriptions since the Covid-19 pandemic
This work, carried out by examining data from the British healthcare system a posteriori, cannot however establish a direct cause and effect relationship. It is, for example, possible that, in certain cases, pneumonia favored the onset of dementia – and therefore the prescription of an associated treatment – and not the other way around.
But several neurologists and geriatricians have praised the seriousness of the methodology and the important nature of such a study, at a time when antipsychotics have seen a resurgence in prescriptions since the Covid crisis.
