CRIS blog: Do long-term prescriptions of multiple antipsychotics contribute to the reduced life expectancy of patients with serious mental illness?

Dr Giouliana Kadra is a postdoctoral research associate at the Institute of Psychiatry, Psychology & Neuroscience at King’s College London.

It has been estimated that the life expectancy of patients with serious mental illnesses is 15 to 20 years shorter than that of the general population. The widespread use of treatment regimens not recommended by existing guidelines, such as antipsychotic polypharmacy (the simultaneous prescription of two or more antipsychotics drugs), has been suggested as a possible reason for this. Furthermore, this risk has been reported to increase with high dose prescriptions, especially when exceeding national recommendations.

Our study addresses a call for further research to examine the risk of death for patients who are prescribed a regular long-term use of two or more antipsychotic drugs simultaneously and to determine whether this polypharmacy-associated risk has any relationship with the cause of death and the antipsychotic dosage.

Using CRIS data (from a large anonymised mental healthcare database), we identified all adult patients with serious mental illness (SMI) who had been prescribed a single antipsychotic or polypharmacy, for six or more months between 2007 and 2014. 

Our key findings were that we found a weak relationship between long-term antipsychotic polypharmacy (multiple drug use) and natural causes of death. However, we found no relationship between polypharmacy and unnatural causes of death. We also found no evidence that the level of antipsychotic dosage increased or decreased the risk of death in patients with serious mental illnesses.

Our findings suggest that the effect of long-term antipsychotic polypharmacy on death is not clear-cut. Future research should focus on examining specific antipsychotic combinations that are commonly prescribed and their effect on particular natural causes of death, such as cardiovascular death.

Furthermore, it is important to note that our research was focussed on the risk of death and the types of causes of death. Despite the lack of a strong relationship between antipsychotic polypharmacy and death, research continues to demonstrate a relationship between antipsychotic polypharmacy and more severe side-effects. So antipsychotic polypharmacy does come with risks, which do need to be taken into account and balanced against patient outcomes.

The full paper, ‘Long-term antipsychotic polypharmacy prescribing in secondary mental health care and the risk of mortality’, was published in Acta Psychiatrica Scandinavica. Read it online:

Tags: CRIS - Publications - Clinical disorders and health behaviours -

By NIHR Maudsley BRC at 20 Nov 2018, 14:34 PM

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